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Sample records for eubacterium rhodothermus marinus

  1. A DnaB intein in Rhodothermus marinus: Indication of recent intein homing across remotely related organisms

    PubMed Central

    Liu, Xiang-Qin; Hu, Zhuma

    1997-01-01

    A dnaB gene encoding a homologue of the Escherichia coli DNA helicase DnaB was cloned and sequenced in the thermophilic eubacterium Rhodothermus marinus, predicting a DnaB protein that harbors an intein. This DnaB intein is 428 amino acid residues long, has several putative intein sequence motifs (including two putative endonuclease motifs), and is capable of protein splicing when produced in E. coli cells. The R. marinus DnaB intein is a close homologue of a DnaB intein in the cyanobacterium Synechocystis sp. strain PCC6803. The two inteins are positioned identically in their respective DnaB proteins. They also share a 54% sequence identity (74% sequence similarity) that is markedly higher than the 37% sequence identity shared by the extein sequences of the two DnaB proteins. Horizontal intein transfer (homing) is therefore invoked to relate these two DnaB inteins. The codon usage of R. marinus DnaB intein coding sequence differs markedly from the codon usages of its flanking extein coding sequences and other genes in the same genome, suggesting more recent acquisition of the DnaB intein in this organism. PMID:9223276

  2. Quinone reduction by Rhodothermus marinus succinate:menaquinone oxidoreductase is not stimulated by the membrane potential

    SciTech Connect

    Fernandes, Andreia S.; Konstantinov, Alexander A.; Teixeira, Miguel; Pereira, Manuela M. . E-mail: mpereira@itqb.unl.pt

    2005-05-06

    Succinate:quinone oxidoreductase (SQR), a di-haem enzyme purified from Rhodothermus marinus, reveals an HQNO-sensitive succinate:quinone oxidoreductase activity with several menaquinone analogues as electron acceptors that decreases with lowering the redox midpoint potential of the quinones. A turnover with the low-potential 2,3-dimethyl-1,4-naphthoquinone that is the closest analogue of menaquinone, although low, can be detected in liposome-reconstituted SQR. Reduction of the quinone is not stimulated by an imposed K{sup +}-diffusion membrane potential of a physiological sign (positive inside the vesicles). Nor does the imposed membrane potential increase the reduction level of the haems in R. marinus SQR poised with the succinate/fumarate redox couple. The data do not support a widely discussed hypothesis on the electrogenic transmembrane electron transfer from succinate to menaquinone catalysed by di-haem SQRs. The role of the membrane potential in regulation of the SQR activity is discussed.

  3. Compatible Solutes in the Thermophilic Bacteria Rhodothermus marinus and "Thermus thermophilus"

    PubMed Central

    Nunes, O. C.; Manaia, C. M.; Da Costa, M. S.; Santos, H.

    1995-01-01

    (sup13)C nuclear magnetic resonance spectroscopy and (sup1)H nuclear magnetic resonance spectroscopy were used to identify and quantify the organic solutes of several strains of halophilic or halotolerant thermophilic bacteria. Two strains of Rhodothermus marinus and four strains of "Thermus thermophilus" grown in complex medium containing NaCl were examined. 2-O-Mannosylglycerate was a major compatible solute in all strains: the Thermus strains accumulated the (beta)-anomer only, whereas both anomers were found in R. marinus. 2-O-(beta)-mannosylglycerate and 2-O-(alpha)-mannosylglycerate were the major compatible solutes in R. marinus. The former was the predominant solute in cells grown in 2.0 and 4.0% NaCl-containing medium, while the latter was the predominant compatible solute at higher salinities. Glutamate, trehalose, and glucose were also present as minor components. The intracellular K(sup+) concentration, as determined by (sup39)K nuclear magnetic resonance spectroscopy, in R. marinus increased with salinity and was sufficient to balance the negative charges of the mannosylglycerate. In addition to 2-O-(beta)-mannosylglycerate, trehalose was a major compatible solute of "T. thermophilus." 2-O-(beta)-Mannosylglycerate was the main solute in medium containing 1.0 or 2.0% NaCl, while trehalose predominated in cells grown in medium supplemented with 3.0 or 4.0% NaCl. Glycine betaine, in lower concentrations, was also detected in two "T. thermophilus" strains. This is the first report of mannosylglycerate as a compatible solute in bacteria. PMID:16535053

  4. Dye-linked D-amino acid dehydrogenase from the thermophilic bacterium Rhodothermus marinus JCM9785: characteristics and role in trans-4-hydroxy-L-proline catabolism.

    PubMed

    Satomura, Takenori; Ishikura, Masaru; Koyanagi, Takashi; Sakuraba, Haruhiko; Ohshima, Toshihisa; Suye, Shin-ichiro

    2015-05-01

    A gene from the thermophilic Gram-negative bacterium Rhodothermus marinus JCM9785, encoding a dye-linked D-amino acid dehydrogenase homologue, was overexpressed in Escherichia coli, and its product was purified and characterized. The expressed enzyme was a highly thermostable dye-linked D-amino acid dehydrogenase that retained more than 80% of its activity after incubation for 10 min at up to 70 °C. When enzyme-catalyzed dehydrogenation of several D-amino acids was carried out using 2,6-dichloroindophenol as the electron acceptor, D-phenylalanine was the most preferable substrate among the D-amino acids tested. Immediately upstream of the dye-linked D-amino acid dehydrogenase gene (dadh) was a gene encoding a 4-hydroxyproline 2-epimerase homologue (hypE). That gene was successfully expressed in E. coli, and the gene product exhibited strong 4-hydroxyproline 2-epimerase activity. Reverse transcription PCR and quantitative real-time PCR showed that the six genes containing the dadh and hypE genes were arranged in an operon and were required for catabolism of trans-4-hydroxy-L-proline in R. marinus. This is the first description of a dye-linked D-amino acid dehydrogenase (Dye-DADH) with broad substrate specificity involved in trans-4-hydroxy-L-proline catabolism. PMID:25472442

  5. Characteristics and sites of infection of Eubacterium nodatum, Eubacterium timidum, Eubacterium brachy, and other asaccharolytic eubacteria.

    PubMed Central

    Hill, G B; Ayers, O M; Kohan, A P

    1987-01-01

    Three new species, Eubacterium nodatum, Eubacterium timidum, and Eubacterium brachy, were described, primarily from subgingival samples taken from patients with moderate and severe adult periodontitis. Except for the isolation of E. brachy from a pleuropulmonary infection, these species have not been reported from other infected body sites. We report on the isolation of these species and an undescribed group (D-6) of asaccharolytic eubacteria also found in periodontal disease from numerous different sites of infection, mostly the head and neck. A similarity in cellular morphological properties of E. nodatum and Actinomyces sp. was noted previously. Additional similarities, particularly to Actinomyces israelii, that we found are the formation of molar tooth colonies and the isolation from cases of lumpy jaw and from the genital tract of women in association with the use of an intrauterine contraceptive device. E. timidum and E. brachy did not occur more often from any particular site outside of the head, neck, and respiratory tract. The group D-6 strains came from a variety of sites in the trunk and pelvis. These species are all obligately anaerobic, asaccharolytic, and generally nonreactive, and they grow poorly and slowly on media commonly used to isolate anaerobic bacteria. L-Lysine (0.5%) markedly stimulated the growth of E. nodatum and, to a lesser extent, another acetate- and butyrate-producing group, Eubacterium sp. group D-6, but we did not find comparable stimulants for the other species. We found the production of phenyl acetate to be a helpful marker in the identification of E. timidum and Eubacterium sp. group D-6. Although the isolation and identification of most of these species remain somewhat difficult, the evidence from dental infections and the present report suggests that these species are potential pathogens that are likely to be overlooked in infected clinical material without special attention to more prolonged incubation and use of enriched

  6. Characterization of the pyrogallol-phloroglucinol isomerase of Eubacterium oxidoreducens.

    PubMed Central

    Krumholz, L R; Bryant, M P

    1988-01-01

    Cell extracts of Eubacterium oxidoreducens, in the presence of dimethyl sulfoxide, catalyzed the conversion of pyrogallol to phloroglucinol with methyl sulfide as a product. The isomerization reaction also proceeded when 1,2,3,5-benzenetetrol was present rather than dimethyl sulfoxide. An assay to quantitate this activity was developed. The assay followed the disappearance of 1,2,4-benzenetriol as determined colorimetrically after incubation with sodium molybdate at neutral pH. The products of this reaction were resorcinol and 2,6-dihydroxyquinone. The enzyme(s) catalyzing this reaction was purified fivefold from cells grown on gallate plus H2. The purification procedure involved treatment with 40% acetone, precipitation with ammonium sulfate, DEAE-cellulose chromatography, concentration by ultrafiltration (molecular weight cutoff, greater than 100,000), and hydroxylapatite chromatography. This preparation had a specific activity of 14.7 mumol/min per mg of protein and a pH optimum of about 7.3. It was strongly inhibited by p-chloromercuribenzoate. The mechanism of the reaction involved oxidation of the pyrogallol followed by introduction of water. The benzenetetrol intermediate was then reduced and dehydrated to phloroglucinol. Images PMID:3372475

  7. TEMPERATURE AND RANGE EXTENSION BY PERKINSUS MARINUS

    EPA Science Inventory

    Between 1990 and 1992, Dermo disease of oysters, caused by Perkinsus marinus, experienced a 500-km northward range extension and is now established as far north as Massachusetts. Climate warming during the 1980s and early 1990s, combined with historical introductions of infected ...

  8. Characterisation of Eubacterium cell wall: peptidoglycan structure determines arthritogenicity

    PubMed Central

    Zhang, X; Rimpilainen, M; Toivanen, P

    2001-01-01

    OBJECTIVE—To elucidate factors involved in the arthritogenicity of bacterial cell walls.
METHODS—For characterisation of an arthritogenic Eubacterium aerofaciens cell wall, peptidoglycan-polysaccharide (PG-PS) polymers were isolated by removing cell wall associated proteins (CWPs), PG and PS moieties were separated, and an attempt was made to de-O-acetylate PG-PS. The cell wall of E limosum was used as a non-arthritogenic control. The chemical composition of these cell wall preparations was analysed by gas chromatography-mass spectrometry. Also, their ability to resist lysozyme degradation and to sustain experimental chronic arthritis was tested.
RESULTS—The observations made with the cell wall of E aerofaciens, an anaerobic habitant of the human intestine, were compared with those reported from a pathogenic Streptococcus, showing that in both strains a complex consisting of PG-PS is required for the induction of chronic arthritis. The PS moiety most probably protects PG from enzyme degradation, allowing prolonged tissue persistence and leading to the chronic synovial inflammation. CWPs attached to PG-PS are not necessary for this function. O-Acetylation of PG, which is required for arthritogenicity of the streptococcal cell wall, seems not to be present in the arthritogenic E aerofaciens PG or only occurs to a small degree; attempts to de-O-acylate the E aerofaciens cell wall did not affect its arthritogenicity or lysozyme resistance.
CONCLUSION—The results obtained indicate that the source of bacterial cell wall plays no part in the chemical or structural requirements for PG to induce chronic cell wall arthritis in the rats; the chemical structure of the PG moiety is decisive.

 PMID:11171690

  9. Complete Genome Sequence of a Carbon Monoxide-Utilizing Acetogen, Eubacterium limosum KIST612 ▿

    PubMed Central

    Roh, Hanseong; Ko, Hyeok-Jin; Kim, Daehee; Choi, Dong Geon; Park, Shinyoung; Kim, Sujin; Chang, In Seop; Choi, In-Geol

    2011-01-01

    Eubacterium limosum KIST612 is an anaerobic acetogenic bacterium that uses CO as the sole carbon/energy source and produces acetate, butyrate, and ethanol. To evaluate its potential as a syngas microbial catalyst, we have sequenced the complete 4.3-Mb genome of E. limosum KIST612. PMID:21036996

  10. Draft Genome Sequence of Chemolithoautotrophic Acetogenic Butanol-Producing Eubacterium limosum ATCC 8486

    PubMed Central

    Song, Yoseb

    2015-01-01

    Eubacterium limosum ATCC 8486 is an anaerobic chemolithoautotrophic acetogenic bacterium that converts and transforms syngas and isoflavonoids to butanol and phytoestrogens, respectively. Here, we report the draft genome sequence of the E. limosum ATCC 8486 (4.37 Mb) strain and its annotation information, including syngas fermentation and denitrification metabolic pathways. PMID:25676768

  11. Complete Genome Sequence of Amino Acid-Utilizing Eubacterium acidaminophilum al-2 (DSM 3953)

    PubMed Central

    Poehlein, Anja; Andreesen, Jan R.

    2014-01-01

    Eubacterium acidaminophilum is a strictly anaerobic, Gram-positive, rod-shaped bacterium which belongs to cluster XI of the Clostridia. It ferments amino acids by a Stickland reaction. The genome harbors a chromosome (2.25 Mb) and a megaplasmid (0.8 Mb). It contains several gene clusters coding for selenocysteine-containing, glycine-derived, and amino acid-degrading reductases. PMID:24926057

  12. Development of sea lamprey (Petromyzon marinus) larvicides

    USGS Publications Warehouse

    Howell, John H.; Lech, John J.; Allen, John L.

    1980-01-01

    Larvicides are used to control sea lamprey (Petromyzon marinus) in the Great Lakes. These larvicides are useful because they are more toxic to sea lamprey than fish species found in the same habitat. The lampricides come from two classes of chemical compounds: (1) halonitrophenols, and (2) halonitrosalicylanilides. Selectivity of the larvicides appears to be based on the differences in the ability of sea lamprey larvae and fishes to detoxify and/or excrete the chemicals. Glucuronide conjugation is an important mechanism for detoxification of these larvicides by fish, and selectivity of larvicides may be due to differences in glucuronyl transferase activity between lamprey and fishes. If more detailed information were available on uptake, metabolism, excretion, and the biochemistry and physiology of lamprey as compared to fishes, it might be possible to design chemicals that would be more selective than those now in use.

  13. Complete genome sequence of Staphylothermus marinus Stetter and Fiala 1986 type strain F1

    SciTech Connect

    Anderson, Iain; Sun, Hui; Lapidus, Alla L.; Copeland, A; Glavina Del Rio, Tijana; Tice, Hope; Dalin, Eileen; Lucas, Susan; Barry, Kerrie; Land, Miriam L; Richardson, P M; Huber, Harald; Kyrpides, Nikos C

    2009-01-01

    Staphylothermus marinus Fiala and Stetter 1986 belongs to the order Desulfurococcales within the archaeal phylum Crenarchaeota. S. marinus is a hyperthermophilic, sulfur-dependent, anaerobic heterotroph. Strain F1 was isolated from geothermally heated sediments at Vulcano, Italy, but S. marinus has also been isolated from a hydrothermal vent on the East Pacific Rise. We report the complete genome of S. marinus strain F1, the type strain of the species. This is the fifth reported complete genome sequence from the order Desulfurococcales.

  14. Anaerobic biodegradation of methyl esters by Acetobacterium woodii and Eubacterium limosum.

    PubMed

    Liu, S; Suflita, J M

    1994-09-01

    The ability of Acetobacterium woodii and Eubacterium limosum to degrade methyl esters of acetate, propionate, butyrate, and isobutyrate was examined under growing and resting-cell conditions. Both bacteria hydrolyzed the esters to the corresponding carboxylates and methanol under either condition. Methanol was further oxidized to formate under growing but not resting conditions. Unlike the metabolism of phenylmethylethers, no H2 requirement was evident for ester biotransformation. The hydrolysis of methyl carboxylates is thermodynamically favorable under standard conditions and the mixotrophic metabolism of ester/CO2 allowed for bacterial growth. These results suggest that the degradation of methyl carboxylates may be a heretofore unrecognized nutritional option for acetogenic bacteria. PMID:7765371

  15. Chemosterilization of the sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Hanson, Lee H.; Manion, Patrick J.

    1978-01-01

    The chemical, P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide (bisazir), was found in laboratory studies to be an effective sterilant for both sexes of adult sea lampreys (Petromyzon marinus) when given intraperitoneally at a dosage of 100 mg per kilogram of body weight. A total of 300 normal spawning-run sea lampreys and 300 injected with bisazir were released into the Big Garlic River, Marquette County, Michigan, (a small stream divided into five sections by natural barriers), to determine the effect of bisazir on the nesting and spawning behavior of the adults and on the production of larvae. The lampreys constructed and spawned in 95 nests. Sterile adults showed no abnormal nest building or spawning behavior. Sterile males competed effectively with normal males for females. Egg samples taken from nests indicated that eggs in nests where sterile males spawned with sterile or normal females did not hatch, although some embryonic development occurred. Extensive surveys with electric shockers produced no larvae in stream sections where sterile males spawned, but yielded numerous larvae in sections where normal males spawned with normal females. These findings suggest that the release of sterile males may be an effective tool in an integrated approach to control of sea lampreys in the Great Lakes.

  16. Phospholipid biosynthesis in the oyster protozoan parasite, Perkinsus marinus.

    PubMed

    Lund, Eric D; Chu, Fu-Lin E

    2002-05-01

    Perkinsus marinus is a protozoan parasite that causes high mortality in its commercially and ecologically important host, the Eastern oyster Crassostrea virginica. In order to understand the host-parasite relationship in lipid metabolism, the ability of P. marinus to synthesize phospholipids from polar headgroup precursors was investigated. Pulse/chase experiments were conducted using radiolabled serine, choline, ethanolamine and inositol. Timecourse incubations revealed that in vitro cultured P. marinus meronts can utilize the cytidine diphosphate-diacylglycerol (CDP-DAG) pathway to synthesize phosphatidylinositol (PI) from inositol and phosphatidylserine (PS) from serine. Serine label was also incorporated into phosphatidylethanolamine (PE), phosphatidylcholine (PC) and lysophosphatidylcholine (LPC). Incubations of P. marinus cells with increasing concentrations of radiolabeled serine resulted in more radioactivity recovered in neutral lipids than in polar lipids at the highest substrate concentration tested (344 microM). This suggests that excess serine label was being utilized for fatty acid synthesis and stored as triacylglycerols. Additional incubations were conducted with radiolabeled choline and ethanolamine at concentrations equimolar to the highest serine concentration tested. Ethanolamine label was also incorporated into PE, PS, PC and LPC. Choline label was incorporated into PC. These results suggest the presence of three pathways for de novo synthesis of phospholipids in P. marinus: CDP-choline, CDP-ethanolamine and CDP-DAG. At equivalent substrate concentrations (344 microM) the highest incorporation of labeled substrate into total phospholipids was with serine followed by ethanolamine and choline, respectively. P. marinus phospholipid biosynthetic capabilities appear to be similar to those of Plasmodium and Trypanosoma species. PMID:12034458

  17. Chronic arthritis induced in rats by cell wall fragments of Eubacterium species from the human intestinal flora.

    PubMed Central

    Severijnen, A J; van Kleef, R; Hazenberg, M P; van de Merwe, J P

    1990-01-01

    To investigate arthritis-inducing properties of Eubacterium species, which are major residents of the human intestinal flora, cell wall fragments (CWF) of several Eubacterium strains were prepared and tested in an animal model. After a single intraperitoneal injection in the rat, CWF of E. aerofaciens, E. contortum, and E. lentum induced a chronic polyarthritis. E. limosum and E. tortuosum CWF induced an acute self-limiting joint inflammation, whereas E. rectale CWF failed to do so. The rhamnose contents of the isolated CWF were not related to their arthritis-inducing properties. Paradoxically, the sensitivity of CWF to lysozyme digestion, which is regarded as a parameter for the clearance of CWF in tissues, appeared to be positively correlated with the ability of Eubacterium CWF to induce chronic joint inflammation. Our findings show the diversity in arthritis-inducing properties among different species of the anaerobic genus Eubacterium and underline the importance of the anaerobic intestinal flora in the induction of joint inflammation. Images PMID:2298490

  18. Increased growth of Bifidobacterium and Eubacterium by germinated barley foodstuff, accompanied by enhanced butyrate production in healthy volunteers.

    PubMed

    Kanauchi, O; Fujiyama, Y; Mitsuyama, K; Araki, Y; Ishii, T; Nakamura, T; Hitomi, Y; Agata, K; Saiki, T; Andoh, A; Toyonaga, A; Bamba, T

    1999-02-01

    Germinated barley foodstuff (GBF) derived from the aleurone and scutellum fractions of germinated barley mainly consists of low-lignified hemicellulose and glutamine-rich protein. GBF improves the proliferation of intestinal epithelial cells and defecation, through the bacterial production of short chain fatty acids (SCFA), especially butyrate. In this study we investigated the mechanism of production of butyrate by microflora in humans and in vitro. Daily administration of 9 g GBF for 14 successive days significantly increased fecal butyrate content. Fecal Bifidobacterium and Eubacterium were also significantly increased by GBF administration in healthy volunteers. Ten anaerobic micro-organisms selected from intestinal microflora were cultured in vitro in the medium containing GBF as a sole carbon source (GBF medium). After a 3-day incubation, 7 strains (Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus, Lactobacillus casei subsp. casei, Bacteroides ovatus, Clostridium butyricum, and Eubacterium limosum) lowered the medium pH producing SCFA. Eubacterium grown together with Bifidobacterium in GBF medium efficiently produced butyrate. On the other hand, GBF changed the intestinal microflora and increased probiotics such as Bifidobacterium in the intestinal tract. As a result, butyrate was produced by the mutual action of Eubacterium and Bifidobacterium. This butyrate is considered to enhance the proliferation of colonic epithelial cells. PMID:9917526

  19. Cutaneous abscess due to Eubacterium lentum in injection drug user: a case report and review of the literature.

    PubMed

    Lattuada, Emanuela; Zorzi, Antonella; Lanzafame, Massimiliano; Antolini, Dario; Fontana, Roberta; Vento, Sandro; Concia, Ercole

    2005-08-01

    We described the first case, to the best of our knowledge, of cutaneous abscess due to Eubacterium lentum in a parenteral drug user, after complete fracture of the right femor. The case underlines the importance of carefully performed microbiological tests, due to the peculiar cultural needs of the micro-organism. PMID:16038756

  20. Suppression of chemiluminescence of eastern oyster (Crassostrea virginica) hemocytes by the protozoan parasite Perkinsus marinus.

    PubMed

    Volety, A K; Chu, F L

    1995-01-01

    Experiments were conducted to determine the ability of the protistan parasite, Perkinsus marinus, to inhibit chemiluminescence of hemocytes from the eastern oyster, Crassostrea virginica. Luminol-enhanced chemiluminescence (CL) was used to measure the production of reactive oxygen intermediates (ROI) generated by oyster hemocytes using zymosan as a stimulant. To determine whether P. marinus suppresses ROI evoked from zymosan-stimulated hemocytes, live or heat killed P. marinus in filtered estuarine water (YRW) (salinity = 20 ppt) were added to (1) zymosan-stimulated hemocytes after CL reached its peak, or (2) hemocytes at the same time as zymosan, and reduction of CL responses were recorded. In both tests, controls received only estuarine water. Live P. marinus meronts significantly suppressed ROI production by zymosan-stimulated hemocytes. The suppression of ROI production was dose dependent. Suppression of ROI production from zymosan-stimulated hemocytes by heat killed P. marinus was significantly less than by live P. marinus. Similarly, CL of hemocytes was reduced, though not significantly when hemocytes were exposed to YRW preincubated with P. marinus. When P. marinus meronts were used as a stimulant, no CL response was elicited. Results of this study suggest that P. marinus cells are able to suppress ROI release from oyster hemocytes, thus evading this component of the host's defense. PMID:7556800

  1. Perkinsus marinus in Crassostrea gigas in the Gulf of California.

    PubMed

    Enríquez-Espinoza, T L; Grijalva-Chon, J M; Castro-Longoria, R; Ramos-Paredes, J

    2010-04-01

    To determine the agent responsible for the massive mortalities of the Pacific oyster Crassostrea gigas in northwest Mexico, 30 oysters were sampled after a severe mortality event in 2006 along the Sonoran coast. Histological analyses revealed the presence of a protozoan and Ray's fluid thioglycollate medium (RFTM) assays showed the presence of Perkinsus sp., identified as P. marinus from the DNA sequence of the internal transcribed spacer (ITS) of the ribosomal RNA (rRNA) gene complex. PCR analyses for Marteilia refringens, M. sydneyi, and Haplosporidium costale were negative. P. marinus presence in the Pacific oyster may be responsible for massive mortalities of the oyster, along with other environmental factors in the Gulf of California. PMID:20481094

  2. Artificial propagation of the sea lamprey Petromyzon marinus

    USGS Publications Warehouse

    Lennon, Robert E.

    1955-01-01

    Observations on the gland products, gonads, and general characteristics of sexually mature sea lampreys, Petromyzon marinus (Linnaeus), from Lake Huron, and a need to obtain some information on very young larval lampreys, prompted an experiment on the stripping and hatching of eggs. Seventeen specimens were selected from a group of spawning migrants which had been trapped in the Ocqueoc River, Michigan, during June and held in live-cars in the lake until early August.

  3. Multiple copies of a bile acid-inducible gene in Eubacterium sp. strain VPI 12708.

    PubMed Central

    Gopal-Srivastava, R; Mallonee, D H; White, W B; Hylemon, P B

    1990-01-01

    Eubacterium sp. strain VPI 12708 is an anaerobic intestinal bacterium which possesses inducible bile acid 7-dehydroxylation activity. Several new polypeptides are produced in this strain following induction with cholic acid. Genes coding for two copies of a bile acid-inducible 27,000-dalton polypeptide (baiA1 and baiA2) have been previously cloned and sequenced. We now report on a gene coding for a third copy of this 27,000-dalton polypeptide (baiA3). The baiA3 gene has been cloned in lambda DASH on an 11.2-kilobase DNA fragment from a partial Sau3A digest of the Eubacterium DNA. DNA sequence analysis of the baiA3 gene revealed 100% homology with the baiA1 gene within the coding region of the 27,000-dalton polypeptides. The baiA2 gene shares 81% sequence identity with the other two genes at the nucleotide level. The flanking nucleotide sequences associated with the baiA1 and baiA3 genes are identical for 930 bases in the 5' direction from the initiation codon and for at least 325 bases in the 3' direction from the stop codon, including the putative promoter regions for the genes. An additional open reading frame (occupying from 621 to 648 bases, depending on the correct start codon) was found in the identical 5' regions associated with the baiA1 and baiA3 clones. The 5' sequence 930 bases upstream from the baiA1 and baiA3 genes was totally divergent. The baiA2 gene, which is part of a large bile acid-inducible operon, showed no homology with the other two genes either in the 5' or 3' direction from the polypeptide coding region, except for a 15-base-pair presumed ribosome-binding site in the 5' region. These studies strongly suggest that a gene duplication (baiA1 and baiA3) has occurred and is stably maintained in this bacterium. Images PMID:2376563

  4. The Alveolate Perkinsus marinus: Biological Insights from EST Gene Discovery

    PubMed Central

    2010-01-01

    Background Perkinsus marinus, a protozoan parasite of the eastern oyster Crassostrea virginica, has devastated natural and farmed oyster populations along the Atlantic and Gulf coasts of the United States. It is classified as a member of the Perkinsozoa, a recently established phylum considered close to the ancestor of ciliates, dinoflagellates, and apicomplexans, and a key taxon for understanding unique adaptations (e.g. parasitism) within the Alveolata. Despite intense parasite pressure, no disease-resistant oysters have been identified and no effective therapies have been developed to date. Results To gain insight into the biological basis of the parasite's virulence and pathogenesis mechanisms, and to identify genes encoding potential targets for intervention, we generated >31,000 5' expressed sequence tags (ESTs) derived from four trophozoite libraries generated from two P. marinus strains. Trimming and clustering of the sequence tags yielded 7,863 unique sequences, some of which carry a spliced leader. Similarity searches revealed that 55% of these had hits in protein sequence databases, of which 1,729 had their best hit with proteins from the chromalveolates (E-value ≤ 1e-5). Some sequences are similar to those proven to be targets for effective intervention in other protozoan parasites, and include not only proteases, antioxidant enzymes, and heat shock proteins, but also those associated with relict plastids, such as acetyl-CoA carboxylase and methyl erythrithol phosphate pathway components, and those involved in glycan assembly, protein folding/secretion, and parasite-host interactions. Conclusions Our transcriptome analysis of P. marinus, the first for any member of the Perkinsozoa, contributes new insight into its biology and taxonomic position. It provides a very informative, albeit preliminary, glimpse into the expression of genes encoding functionally relevant proteins as potential targets for chemotherapy, and evidence for the presence of a relict

  5. Molecular details of a starch utilization pathway in the human gut symbiont Eubacterium rectale

    PubMed Central

    Cockburn, Darrell W.; Orlovsky, Nicole I.; Foley, Matthew H.; Kwiatkowski, Kurt J.; Bahr, Constance M.; Maynard, Mallory; Demeler, Borries; Koropatkin, Nicole M.

    2015-01-01

    Summary Eubacterium rectale is a prominent human gut symbiont yet little is known about the molecular strategies this bacterium has developed to acquire nutrients within the competitive gut ecosystem. Starch is one of the most abundant glycans in the human diet, and E. rectale increases in vivo when the host consumes a diet rich in resistant starch, although it is not a primary degrader of this glycan. Here we present the results of a quantitative proteomics study in which we identify two glycoside hydrolase 13 family enzymes, and three ABC transporter solute-binding proteins that are abundant during growth on starch and, we hypothesize, work together at the cell surface to degrade starch and capture the released maltooligosaccharides. EUR_21100 is a multidomain cell wall anchored amylase that preferentially targets starch polysaccharides, liberating maltotetraose, while the membrane associated maltogenic amylase EUR_01860 breaks down maltooligosaccharides longer than maltotriose. The three solute-binding proteins display a range of glycan-binding specificities that ensure the capture of glucose through maltoheptaose and some α1,6-branched glycans. Taken together, we describe a pathway for starch utilization by E. rectale DSM 17629 that may be conserved among other starch-degrading Clostridium cluster XIVa organisms in the human gut. PMID:25388295

  6. Enzyme degradation and proinflammatory activity in arthritogenic and nonarthritogenic Eubacterium aerofaciens cell walls.

    PubMed

    Zhang, X; Rimpiläinen, M; Simelyte, E; Toivanen, P

    2001-12-01

    Two almost-identical strains of Eubacterium aerofaciens isolated from the normal human gut flora were used. The cell wall (CW) of one strain with a peptidoglycan (PG) type A4alpha induces chronic arthritis in the rat after a single intraperitoneal injection, whereas CW of the other with PG type A4beta induces only a transient acute arthritis. The CW of the arthritogenic E. aerofaciens was a twofold-more-potent stimulator of the proinflammatory cytokines tumor necrosis factor alpha (TNF-alpha) and monocyte chemoattractant protein 1 (MCP-1) than the nonarthritogenic CW. After degradation with mutanolysin, the capacity of the arthritogenic PG to stimulate production of TNF-alpha and MCP-1 was significantly increased, whereas that of the nonarthritogenic PG was significantly decreased. In other words, after enzyme degradation the arthritogenic PG had a four- to fivefold-stronger stimulatory capacity than that of the enzyme-treated nonarthritogenic PG. These findings indicate that the arthritogenicity of CW or a PG is not dependent on the enzyme resistance alone but also on how the PG fragments released by enzyme degradation stimulate the production of proinflammatory cytokines. PMID:11705898

  7. ANTIOXIDANT ENZYMES, POTENTIAL VIRULENT FACTORS, IN DIFFERENT STRAINS OF THE OYSTER PROTOZOAN PARASITE, PERKINSUS MARINUS

    EPA Science Inventory

    The oyster protozoan parasite, Perkinsus marinus, is one of the two important parasites causing severe mortality in the eastern oysters (Crassostrea virginica) on the US east coast. Our recent study suggests that P. marinus cells and its extracellular products (ECP) could scaveng...

  8. COMPARISON OF IN VITRO-CULTURED AND WILD-TYPE PERKINSUS MARINUS I: PATHOGEN VIRULENCE

    EPA Science Inventory

    Perkinsus marinus is a highly contagious pathogen of the eastern oyster Crassostrea virginica. Until recently, transmission studies have employed wild-type parasites isolated directly from infected oysters. Newly developed methods to propagate P. marinus in vitro have led to usin...

  9. Characterization of NADP-dependent 7 beta-hydroxysteroid dehydrogenases from Peptostreptococcus productus and Eubacterium aerofaciens.

    PubMed Central

    Hirano, S; Masuda, N

    1982-01-01

    Peptostreptococcus productus strain b-52 (a human fecal isolate) and Eubacterium aerofaciens ATCC 25986 were found to contain NADP-dependent 7 beta-hydroxysteriod dehydrogenase activity. The enzyme was synthesized constitutively by both organisms, and the enzyme yields were suppressed by the addition of 0.5 mM 7 beta-hydroxy bile acid to the growth medium. Purification of the enzyme by chromatography resulted in preparations with 3.5 (P. productus b-52, on Sephadex G-200) and 1.8 (E. aerofaciens, on Bio-Gel A-1.5 M) times the activity of the crude cell extracts. A pH optimum of 9.8 and a molecular weight of approximately 53,000 were shown for the enzyme of strain b-52, and an optimum pH at 10.5 and a molecular weight of 45,000 was shown for that from strain ATCC 25986. Kinetic studies revealed that both enzyme preparations oxidized the 7 beta-hydroxy group in unconjugated and conjugated bile acids, a lower Km value being demonstrated with free bile acid than with glycine and taurine conjugates. No measureable activity against 3 alpha-, 7 alpha-, or 12 alpha-hydroxy groups was detected in either enzyme preparation. When tested with strain ATCC 25986, little 7 beta-hydroxy-steroid dehydrogenase activity was detected in cells grown in the presence of glucose in excess. The enzyme from strain b-52 was found to be heat labile (90% inactivation at 50 degrees C for 3 min) and highly sensitive to sulfhydryl inhibitors. PMID:6954878

  10. Eubacterium rangiferina, a novel usnic acid-resistant bacterium from the reindeer rumen

    NASA Astrophysics Data System (ADS)

    Sundset, Monica A.; Kohn, Alexandra; Mathiesen, Svein D.; Præsteng, Kirsti E.

    2008-08-01

    Reindeer are able to eat and utilize lichens as an important source of energy and nutrients. In the current study, the activities of antibiotic secondary metabolites including usnic, antranoric, fumarprotocetraric, and lobaric acid commonly found in lichens were tested against a collection of 26 anaerobic rumen bacterial isolates from reindeer ( Rangifer tarandus tarandus) using the agar diffusion method. The isolates were identified based on their 16S ribosomal ribonucleic acid (rRNA) gene sequences. Usnic acid had a potent antimicrobial effect against 25 of the isolates, belonging to Clostridiales, Enterococci, and Streptococci. Isolates of Clostridia and Streptococci were also susceptible to atranoric and lobaric acid. However, one isolate (R3_91_1) was found to be resistant to usnic, antranoric, fumarprotocetraric, and lobaric acid. R3_91_1 was also seen invading and adhering to lichen particles when grown in a liquid anaerobic culture as demonstrated by transmission electron microscopy. This was a Gram-negative, nonmotile rod (0.2-0.7 × 2.0-3.5 μm) with a deoxyribonucleic acid G + C content of 47.0 mol% and main cellular fatty acids including 15:0 anteiso-dimethyl acetal (DMA), 16:0 iso-fatty acid methyl ester (FAME), 13:0 iso-3OH FAME, and 17:0 anteiso-FAME, not matching any of the presently known profiles in the MIDI database. Combined, the phenotypic and genotypic traits including the 16S rRNA gene sequence show that R3_91_1 is a novel species inside the order Clostridiales within the family Lachnospiraceae, for which we propose the name Eubacterium rangiferina. This is the first record of a rumen bacterium able to tolerate and grow in the presence of usnic acid, indicating that the rumen microorganisms in these animals have adapted mechanisms to deal with lichen secondary metabolites, well known for their antimicrobial and toxic effects.

  11. Additional characteristics of one-carbon-compound utilization by Eubacterium limosum and Acetobacterium woodii.

    PubMed

    Sharak Genthner, B R; Bryant, M P

    1987-03-01

    Growth characteristics of Eubacterium limosum and Acetobacterium woodii during one-carbon-compound utilization were investigated. E. limosum RF grew with formate as the sole energy source. Formate also replaced a requirement for CO2 during growth with methanol. Growth with methanol required either rumen fluid, yeast extract, or acetate, but their effects were not additive. Cultures were adapted to grow in concentrations of methanol of up to 494 mM. Growth occurred with methanol in the presence of elevated levels of Na+ (576 mM). The pH optima for growth with methanol, H2-CO2, and carbon monoxide were similar (7.0 to 7.2). Growth occurred with glucose at a pH of 4.7, but not at 4.0. The apparent Km values for methanol and hydrogen were 2.7 and 0.34 mM, respectively. The apparent Vmax values for methanol and hydrogen were 1.7 and 0.11 mumol/mg of protein X min-1, respectively. The Ks value for CO was estimated to be less than 75 microM. Cellular growth yields were 70.5, 7.1, 3.38, and 0.84 g (dry weight) per mol utilized for glucose, methanol, CO, and hydrogen (in H2-CO2), respectively. E. limosum was also able to grow with methoxylated aromatic compounds as energy sources. Glucose apparently repressed the ability of E. limosum to use methanol, hydrogen, or isoleucine but not CO. Growth with mixtures of methanol, H2, CO, or isoleucine was not diauxic. The results, especially the relatively high apparent Km values for H2 and methanol, may indicate why E. limosum does not usually compete with rumen methanogens for these energy sources.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3579266

  12. Amylibacter marinus gen. nov., sp. nov., isolated from surface seawater.

    PubMed

    Teramoto, Maki; Nishijima, Miyuki

    2014-12-01

    A Gram-stain-negative, non-motile, mesophilic, aerobic, rod-shaped bacterium, designated strain 2-3(T), was isolated from surface seawater at Muroto city, Kochi prefecture, Japan. This strain grew well with starch. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain fell within the family Rhodobacteraceae and that the strain was related most closely to the genus Pacificibacter (94.0 % sequence similarity to the type strain). The DNA G+C content was 52.4 mol%. The major fatty acids were C18 : 1ω7c, C14 : 0 and C16 : 0. The major polar lipids were phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, one unidentified lipid, one unidentified aminolipid and one unidentified phospholipid. The major isoprenoid quinone was Q-10. Strain 2-3(T) did not grow at 4 or 35 °C, while the type strain of the type species of the genus Pacificibacter grows at both temperatures. From the taxonomic data obtained in this study, it is proposed that strain 2-3(T) be placed into a novel genus and species named Amylibacter marinus gen. nov., sp. nov. in the family Rhodobacteraceae. The type strain of Amylibacter marinus is 2-3(T) ( = NBRC 110140(T) = LMG 28364(T)). PMID:25225261

  13. Perkinsus marinus in coastal Georgia, USA, following a prolonged drought.

    PubMed

    Power, A; McCrickard, B; Mitchell, M; Covington, E; Sweeney-Reeves, M; Payne, K; Walker, R

    2006-12-14

    Oysters Crassostrea virginica are 'keystone' estuarine species in the southeastern USA, providing essential fish habitat, food for human consumption, filtration of water bodies, and protection against shoreline erosion. Relatively few oyster pathology studies have been conducted in Georgia. The parasitic protozoan Perkinsus marinus was first observed here in the 1960s, but has not been investigated since the late 1990s, when increasing oyster infection levels were apparent. In the late 1990s and early 2000s, the region suffered a prolonged drought, resulting in elevated salinities and the proliferation of various diseases in the marine environment. By 2003, salinities had returned to normal levels, but the effect of the drought on oysters was unknown. In June 2003, oyster reefs throughout Chatham County were sampled to evaluate the prevalence and intensity of P. marinus. The disease appears to have remained prevalent in the coastal waters of Georgia (100% prevalence at some sites), but the intensity was low, ranging from 0 to 1.83 on a scale where heavy infections rated a score of 5. While the disease did not occur at levels high enough to cause oyster mortalities, further monitoring, particularly on a temporal scale, is warranted. PMID:17260834

  14. The Common Gut Microbe Eubacterium hallii also Contributes to Intestinal Propionate Formation

    PubMed Central

    Engels, Christina; Ruscheweyh, Hans-Joachim; Beerenwinkel, Niko; Lacroix, Christophe; Schwab, Clarissa

    2016-01-01

    Eubacterium hallii is considered an important microbe in regard to intestinal metabolic balance due to its ability to utilize glucose and the fermentation intermediates acetate and lactate, to form butyrate and hydrogen. Recently, we observed that E. hallii is capable of metabolizing glycerol to 3-hydroxypropionaldehyde (3-HPA, reuterin) with reported antimicrobial properties. The key enzyme for glycerol to 3-HPA conversion is the cobalamin-dependent glycerol/diol dehydratase PduCDE which also utilizes 1,2-propanediol (1,2-PD) to form propionate. Therefore our primary goal was to investigate glycerol to 3-HPA metabolism and 1,2-PD utilization by E. hallii along with its ability to produce cobalamin. We also investigated the relative abundance of E. hallii in stool of adults using 16S rRNA and pduCDE based gene screening to determine the contribution of E. hallii to intestinal propionate formation. We found that E. hallii utilizes glycerol to produce up to 9 mM 3-HPA but did not further metabolize 3-HPA to 1,3-propanediol. Utilization of 1,2-PD in the presence and absence of glucose led to the formation of propanal, propanol and propionate. E. hallii formed cobalamin and was detected in stool of 74% of adults using 16S rRNA gene as marker gene (n = 325). Relative abundance of the E. hallii 16S rRNA gene ranged from 0 to 0.59% with a mean relative abundance of 0.044%. E. hallii PduCDE was detected in 63 to 81% of the metagenomes depending on which subunit was investigated beside other taxons such as Ruminococcus obeum, R. gnavus, Flavonifractor plautii, Intestinimonas butyriciproducens, and Veillonella spp. In conclusion, we identified E. hallii as a common gut microbe with the ability to convert glycerol to 3-HPA, a step that requires the production of cobalamin, and to utilize 1,2-PD to form propionate. Our results along with its ability to use a broad range of substrates point at E. hallii as a key species within the intestinal trophic chain with the potential to

  15. Evidence for a multigene family involved in bile acid 7-dehydroxylation in Eubacterium sp. strain VPI 12708.

    PubMed Central

    White, W B; Franklund, C V; Coleman, J P; Hylemon, P B

    1988-01-01

    Eubacterium sp. strain VPI 12708 is a human intestinal isolate which has an inducible bile acid 7-dehydroxylation activity. At least two cholic acid-induced polypeptides, with molecular masses of 27,000 and 45,000 daltons, respectively, coelute with bile acid 7-dehydroxylation activity. The 45,000-dalton polypeptide appears to be encoded by a cholic acid-induced mRNA species of greater than 6 kilobases, which suggests that the gene coding for this polypeptide is part of a larger operon. A gene has been cloned which flanks the gene encoding the 45,000-dalton polypeptide, in the upstream (5') direction. This gene appears to encode a second 27,000-dalton polypeptide. The gene bears striking homology at both the nucleotide (80%) and deduced amino acid sequence (89%) levels with the gene which encodes the 27,000-dalton polypeptide that has been shown previously to be involved in the bile acid 7-dehydroxylation reaction sequence. The implications of this homology and the possible function(s) of the two homologous genes in bile acid 7-dehydroxylation are discussed. Evidence is presented which suggests that the two homologous genes involved in bile acid 7-dehydroxylation may be part of a larger multigene family in Eubacterium sp. strain VPI 12708. Images PMID:3170477

  16. IN VITRO KILLING OF PERKINSUS MARINUS BY HEMOCYTES OF OYSTERS CRASSOSTREA VIRGINICA

    EPA Science Inventory

    A colorimetric microbicidal assay was adapted, optimized and applied in experiments to characterize the in vitro capacity of eastern oyster (Crassostrea virginica) hemocytes to kill cultured isolates of Perkinsus marinus, a protozoan parasite causing a highly destructive disease...

  17. Systematic evaluation of factors controlling Perkinsus marinus transmission dynamics in lower Chesapeake Bay.

    PubMed

    Ragone Calvo, Lisa M; Dungan, Christopher F; Roberson, Bob S; Burreson, Eugene M

    2003-08-15

    The transmission of Perkinsus marinus in eastern oysters Crassostrea virginica in relation to water temperature, host oyster mortality, and water-column abundance of anti-P. marinus antibody-labeled cells was systematically examined for 20 mo at a site in the lower York River, Virginia, USA. Uninfected sentinel oysters were naturally exposed to the parasite at 2 wk intervals throughout the course of the study to determine the periodicity and rates of parasite transmission. The timing and magnitude of disease-associated oyster mortalities in a local P. marinus-infected oyster population were estimated by monitoring a captive subset of the local oyster population. Flow cytometric immunodetection methods were employed to estimate the abundance of P. marinus cells in water samples collected 3 times each week. The acquisition of P. marinus infections by naïve sentinel oysters occurred sporadically at all times of the year; however, the highest incidence of infection occurred during the months of August and September. This window of maximum parasite transmission coincided with the death of infected hosts within the captive local oyster population. Counts of antibody-labeled cells ranged from 10 to 11900 cells l(-1), with the highest abundances in July and August coincident with maximum summer temperatures. A statistically significant relationship between water-column parasite abundance and infection-acquisition rate was not observed; however, highest parasite-transmission rates in both years occurred during periods of elevated water-column abundance of parasite cells. These results support the prevailing model of P. marinus transmission dynamics by which maximum transmission rates are observed during periods of maximum P. marinus-associated host mortality. However, our results also indicate that transmission can occur when host mortality is low or absent, so alternative mortality-independent dissemination mechanisms are likely. The results also suggest that atypically

  18. Agreement among observers classifying larval sea lamprey (Petromyzon marinus) habitat

    USGS Publications Warehouse

    Mullett, K.M.; Bergstedt, R.A.

    2003-01-01

    Estimates of larval sea lamprey (Petromyzon marinus) abundance are used to rank Great Lakes tributaries for lampricide treatment. Observers subjectively stratify habitat into three categories: type I = preferred, type II = acceptable, type III = unacceptable. Agreement was evaluated among eight observers classifying habitats in small discrete plots in two Lake Superior tributaries, the Rock and Chocolay rivers, and among four observers classifying and measuring the amount of each habitat type along random transects in the Rock River. Agreement among the eight observers classifying habitat plots was high (Chocolay, ?? = 0.742 and Rock, ?? = 0.785). The amounts of types I, II, and III habitat estimated were statistically different among observers. However, the amount of variability found in the classification and measurement of habitat by observers had little effect on the ranking of 51 streams considered for lampricide treatment.

  19. Agreement among observers classifying larval sea lamprey (Petromyzon marinus) habitat

    USGS Publications Warehouse

    Mullett, Katherine M.; Bergstedt, Roger A.

    2003-01-01

    Estimates of larval sea lamprey (Petromyzon marinus) abundance are used to rank Great Lakes tributaries for lampricide treatment. Observers subjectively stratify habitat into three categories: type I = preferred, type II = acceptable, type III = unacceptable. Agreement was evaluated among eight observers classifying habitats in small discrete plots in two Lake Superior tributaries, the Rock and Chocolay rivers, and among four observers classifying and measuring the amount of each habitat type along random transects in the Rock River. Agreement among the eight observers classifying habitat plots was high (Chocolay, k = 0.742 and Rock, k = 0.785). The amounts of types I, II, and III habitat estimated were statistically different among observers. However, the amount of variability found in the classification and measurement of habitat by observers had little effect on the ranking of 51 streams considered for lampricide treatment.

  20. Identification of two spliced leader RNA transcripts from Perkinsus marinus.

    PubMed

    Hearne, Jennifer L; Pitula, Joseph S

    2011-01-01

    Spliced leader (SL) variants are present in a number of mRNAs from Perkinsus marinus. Three different SLs of 22 nucleotides (nt) in length were previously reported, with a consensus sequence of (DCCGUAGCCAUYUUGGCUCAAG). A truncated 21 nt SL, with an (A) at nt-1 and a (U) deletion at nt-13, has also been reported. Here, we report an additional 21 nt SL variant with (G) at nt-1. Using cDNA analysis, a full-length SL RNA transcript was identified for both 21 nt SLs (SL2[A] and SL2[G]). This transcript is 81 nt in length and contains a conserved transcription termination sequence present in closely related dinoflagellates. PMID:21435079

  1. Tamlicoccus marinus gen. nov., sp. nov., isolated from seawater.

    PubMed

    Lee, Soon Dong

    2013-06-01

    A novel actinobacterial strain was isolated from a seawater sample collected on Mara Island, Jeju, Republic of Korea. Cells of this organism were aerobic, Gram-positive, non-spore-forming, non-motile cocci that occurred singly or in pairs. Colonies were circular, smooth, convex and white-cream in colour. Phylogenetic analyses based on 16S rRNA gene sequences showed that the organism belonged to the family Dermacoccaceae and formed a monophyletic clade between the type strains of Demetria terragena (96.8% similarity) and Branchiibius hedensis (95.2% similarity). The cell-wall peptidoglycan contained L-lysine, alanine, aspartic acid, glutamic acid, glycine and serine, indicating that the isolate possessed peptidoglycan type A4α. The whole-cell sugars were galactose, glucose, mannose, xylose, arabinose, ribose and rhamnose. The major menaquinone was MK-8(H4). The polar lipids contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, an unknown phospholipid and five unknown lipids. The cellular fatty acid profile was represented by large amounts of iso-methyl branched and monounsaturated iso- and anteiso-methyl branched acids, along with the presence of a diagnostic 10-methyl acid. The G+C content of the DNA was 71 mol%. On the basis of data from polyphasic analyses presented here, strain MSW-24(T) is considered to represent a novel species of a new genus in the family Dermacoccaceae, for which the name Tamlicoccus marinus gen. nov., sp. nov. is proposed. The type strain of Tamlicoccus marinus is MSW-24(T) (=KCTC 19485(T)=DSM 21415(T)). PMID:23041643

  2. Reclassification of Bacteriovorax marinus as Halobacteriovorax marinus gen. nov., comb. nov. and Bacteriovorax litoralis as Halobacteriovorax litoralis comb. nov.; description of Halobacteriovoraceae fam. nov. in the class Deltaproteobacteria

    PubMed Central

    Williams, Henry N.; Stine, O. Colin

    2015-01-01

    The taxonomic status of saltwater Bdellovibrio-like prokaryotic predators has been revised to assign species to Halobacteriovorax gen. nov. A reclassification of Bacteriovorax marinus as Halobacteriovorax marinus comb. nov. (type strain ATCC BAA-682T = DSM 15412T) and Bacteriovorax litoralis as Halobacteriovorax litoralis comb. nov. (type strain ATCC BAA-684T = DSM 15409T) is proposed. This revision is necessary because a previous proposal to retain saltwater isolates as species of Bacteriovorax and reclassify Bacteriovorax stolpii as Bacteriolyticum stolpii was not approved. The type species of a genus cannot be reassigned to another genus. Bacteriovorax stolpii is thus retained as the type species of Bacteriovorax and Halobacteriovorax marinus is the type species of Halobacteriovorax and of Halobacteriovoraceae fam. nov. PMID:25406234

  3. Acute toxicity, uptake and accumulation kinetics of nickel in an invasive copepod species: Pseudodiaptomus marinus.

    PubMed

    Tlili, Sofiène; Ovaert, Julien; Souissi, Anissa; Ouddane, Baghdad; Souissi, Sami

    2016-02-01

    Pseudodiaptomus marinus is a marine calanoid copepod originating of the Indo-Pacific region, who has successfully colonized new areas and it was recently observed in the European side of the Mediterranean Sea as well as in the North Sea. Actually, many questions were posed about the invasive capacity of this copepod in several non-native ecosystems. In this context, the main aim of this study was to investigate the tolerance and the bioaccumulation of metallic stress in the invasive copepod P. marinus successfully maintained in mass culture at laboratory conditions since 2 years. In order to study the metallic tolerance levels of P. marinus, an emergent trace metal, the nickel, was chosen. First, lethal concentrations determination experiments were done for 24, 48, 72 and 96 h in order to calculated LC50% but also to select a relevant ecological value for the suite of experiments. Then, three types of experiments, using a single concentration of nickel (correspond the 1/3 of 96 h-LC50%) was carried in order to study the toxico-kinetics of nickel in P. marinus. Concerning lethal concentrations, we observed that P. marinus was in the same range of sensitivity compared to other calanoid copepods exposed to nickel in the same standardized experimental conditions. Results showed that the uptake of nickel in P. marinus depends from the pathways of entrance (water of food), but also that Isochrysis galbana, used as a food source, has an important bioaccumulation capacity and a rapid uptake of nickel. PMID:26519805

  4. Unusual Enterobacteriaceae: H2S+ Shigella sonnei, one authentic and one false positive due to contamination with the obligate anaerobe Eubacterium lentum.

    PubMed Central

    Farmer, J J; Riddle, C F; Stargel, M D; Iida, H; Aikawa, T; Achanzar, D; Taylor, W I

    1976-01-01

    A mixture of Shigella sonnei and Eubacterium lentum produced H2S in triple sugar iron agar; however, neither produced any in pure culture. A second culture of S. sonnei, isolated in Japan, is thought to be the first documented H2S+ Shigella. PMID:767362

  5. Evaluating potential artefacts of photo-reversal on behavioral studies with nocturnal invasive sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Barnett, Matthew; Imre, Istvan; Wagner, Michael C.; Di Rocco, Richard T.; Johnson, Nicholas; Brown, Grant E

    2016-01-01

    Sea lampreys (Petromyzon marinus L., 1758) are nocturnal, so experiments evaluating their behaviour to chemosensory cues have typically been conducted at night. However, given the brief timeframe each year that adult P. marinus are available for experimentation, we investigated whether P. marinus exposed to a 12 h shifted diurnal cycle (reversed photoperiod) could be tested in a darkened arena during the day and show the same response to chemosensory cues as natural photoperiod P. marinus that were tested during the night. Ten replicates of 10 P. marinus, from each photoperiod, were exposed to deionized water (negative control), 2-phenylethylamine hydrochloride (PEA HCl, putative predator cue), or P. marinus whole-body extract (conspecific alarm cue). All P. marinus demonstrated a significant avoidance response to both cues. No significant differences were found in avoidance to PEA HCl between photoperiods. Avoidance of P. marinus whole-body extract was significantly stronger in natural compared with reversed photoperiod P. marinus. The use of reversed photoperiod subjects is suitable for examining the presence or absence of avoidance in response to novel chemosensory alarm cues, or the change in the magnitude of antipredator response. Studies investigating the natural magnitude of antipredator response should use natural photoperiod experimental subjects.

  6. Early host-pathogen interactions in a marine bivalve: Crassostrea virginica pallial mucus modulates Perkinsus marinus growth and virulence.

    PubMed

    Pales Espinosa, Emmanuelle; Winnicki, Sarah; Allam, Bassem

    2013-06-13

    Perkinsus marinus is an important protistan parasite of the eastern oyster Crassostrea virginica. Recent findings showed that oyster pallial organs (mantle, gills) are a major portal of entry for the parasite. Therefore, mucus covering these organs represents the first host effectors encountered by P. marinus. This study consisted of several experiments designed to investigate the effect of oyster pallial mucus on the growth, protease production and infectivity of P. marinus. In each experiment, P. marinus performance in cultures supplemented with pallial mucus (mantle, gill, or both) was compared to that of parasite cells grown in unsupplemented media or in cultures supplemented with oyster plasma or digestive extracts. P. marinus grown in media supplemented with C. virginica mantle mucus showed a significantly higher growth rate than cultures enriched with the other supplemental extracts, while cultures grown in gill mucus promoted higher protease production. Conversely, P. marinus grown in cultures supplemented with pallial mucus of the non-compatible host Crassostrea gigas (Pacific oyster) were dramatically inhibited. Challenge experiments showed a significant increase in P. marinus virulence in cultures supplemented with C. virginica pallial mucus as compared to unsupplemented cultures or to those supplemented with digestive extract or plasma. These results suggest that C. virginica mucus plays a significant role in the pathogenesis of P. marinus by enhancing the proliferation and the infectivity of this devastating parasite. The contrasting results obtained with both oyster species indicate that P. marinus host specificity may begin in the mucus. PMID:23759561

  7. Apoptosis as a host defense mechanism in Crassostrea virginica and its modulation by Perkinsus marinus.

    PubMed

    Hughes, Francis M; Foster, Brent; Grewal, Snimar; Sokolova, Inna M

    2010-08-01

    Dermo disease caused by the obligatory intracellular protozoan Perkinsus marinus causes extensive oyster mortalities leading to tremendous losses in the oyster industry and damage to estuarine ecosystems. To better understand the mechanisms of the parasite's evasion of the host immune defense system, we have investigated the molecular mechanisms of P.marinus-induced inhibition of apoptosis in oyster cells as a potential parasite's survival strategy. We found that P. marinus modulates apoptosis of oyster immune cells (hemocytes) in a way that may help the parasite to establish infection. We found an increase in apoptosis in the initial stages of infection in vitro and in vivo, consistent with a host response to this intracellular parasite. During infection with highly virulent strains of P. marinus, this was followed by suppression and a return of apoptosis to basal levels 8-24 h post-infection, strongly indicating the parasite-induced inhibition of the immune response. In contrast, during infections with intermediate or low virulence strains of P. marinus, a transient suppression of apoptosis 4-8 h post-infection was followed by sustained elevation of hemocyte apoptosis at later stages, indicating that hemocytes were able to overcome the parasite-induced suppression and successfully combat the infection. Studies of the mechanisms of P. marinus-induced apoptosis indicated that the early post-infection stimulation of apoptosis is caspase-independent. However, this process can be driven (although to a lesser degree) by the killed parasite, suggesting that oyster hemocytes respond to cell surface molecules of P. marinus. Overall, this study provides novel insights into pathogen-induced modulation of apoptosis and its role in parasite virulence and establishment of infections. PMID:20371290

  8. Signal recognition particle RNA in dinoflagellates and the Perkinsid Perkinsus marinus.

    PubMed

    Zhang, Huan; Campbell, David A; Sturm, Nancy R; Rosenblad, Magnus A; Dungan, Christopher F; Lin, Senjie

    2013-09-01

    In dinoflagellates and perkinsids, the molecular structure of the protein translocating machinery is unclear. Here, we identified several types of full-length signal recognition particle (SRP) RNA genes from Karenia brevis (dinoflagellate) and Perkinsus marinus (perkinsid). We also identified the four SRP S-domain proteins, but not the two Alu domain proteins, from P. marinus and several dinoflagellates. We mapped both ends of SRP RNA transcripts from K. brevis and P. marinus, and obtained the 3' end from four other dinoflagellates. The lengths of SRP RNA are predicted to be ∼260-300 nt in dinoflagellates and 280-285 nt in P. marinus. Although these SRP RNA sequences are substantially variable, the predicted structures are similar. The genomic organization of the SRP RNA gene differs among species. In K. brevis, this gene is located downstream of the spliced leader (SL) RNA, either as SL RNA-SRP RNA-tRNA gene tandem repeats, or within a SL RNA-SRP RNA-tRNA-U6-5S rRNA gene cluster. In other dinoflagellates, SRP RNA does not cluster with SL RNA or 5S rRNA genes. The majority of P. marinus SRP RNA genes array as tandem repeats without the above-mentioned small RNA genes. Our results capture a snapshot of a potentially complex evolutionary history of SRP RNA in alveolates. PMID:23994724

  9. Perkinsus marinus, a protozoan parasite of the eastern oyster, has a requirement for dietary sterols.

    PubMed

    Lund, Eric D; Chu, Fu-Lin E; Soudant, Philippe; Harvey, Ellen

    2007-01-01

    Perkinsus marinus, a protozoan parasite of the eastern oyster, Crassostrea virginica, causes high mortality in its host along the Atlantic and Gulf coasts of North America. P. marinus meronts cultured in vitro in medium containing complete lipid supplement (cod liver oil, cholesterol and alpha tocopherol acetate in detergent) are able to synthesize a wide variety of lipids, yet cultures cannot be maintained in lipid-free medium. To determine P. marinus lipid requirements meronts were inoculated into media containing different combinations of lipid components in detergent. Treatments included complete lipid supplement (positive control), detergent only (negative control), cholesterol in detergent, alpha tocopherol acetate in detergent and cholesterol+alpha tocopherol acetate in detergent. Meronts proliferated in the positive control medium and media containing cholesterol or cholesterol+alpha tocopherol acetate, but failed to proliferate in the negative control medium and the medium containing just alpha tocopherol acetate. Gas chromatography analysis of P. marinus meronts grown in medium with added (13)C sodium acetate (0.5 mg mL(-1)) revealed the presence of fatty acids containing (13)C, but the only sterol present was cholesterol containing no (13)C. These results suggest that P. marinus cannot synthesize sterols and must sequester them from its host. PMID:17112755

  10. Consumption and feeding preference of Echinogammarus marinus on two different algae: Fucus vesiculosus and Ulva intestinalis

    NASA Astrophysics Data System (ADS)

    Martins, Irene; Leite, Nuno; Constantino, Emanuel

    2014-01-01

    Echinogammarus marinus constitutes the most abundant amphipod species in Fucus spp. assemblages from many North Atlantic estuaries. However, there are some doubts about the real use of fucoids by the amphipod. Whilst some studies report the ingestion of Fucus vesiculosus by E. marinus, others suggest that the amphipod preference for fucoids is mostly related to sheltering rather than feeding, due to the high phlorotannin content of brown algae. The purpose of the present work was to disentangle this issue by checking the consumption rate and feeding preference of E. marinus on F. vesiculosus, its preferential habitat, and on Ulva intestinalis, a green algae abundant in the Mondego estuary (Western Coast of Portugal) and usually considered as highly palatable for herbivores. In a 2-stage laboratorial setup, fresh disks of the two types of algae were offered to E. marinus for three days. Consumption rates were estimated from differences between algal and animal initial and final fresh weights using a control correction factor, while preference was tested by differences in algal consumption rates when no choice was offered (stage 1) and when the two algae were offered simultaneously (stage 2). Results showed that E. marinus effectively consumed fresh F. vesiculosus in much higher amounts than U. intestinalis and significantly preferred to consume F. vesiculosus over U. intestinalis. Therefore, feeding habits must be one of the factors related to the close association of the amphipod with F. vesiculosus, although other factors may also be involved (e.g. sheltering).

  11. Saccharicrinis marinus sp. nov., isolated from marine sediment.

    PubMed

    Liu, Qian-Qian; Li, Juan; Xiao, Di; Lu, Jin-Xing; Chen, Guan-Jun; Du, Zong-Jun

    2015-10-01

    A novel bacterial strain, designated Y11T, was isolated from marine sediment at Weihai in China. Comparative analysis of 16S rRNA gene sequences demonstrated that the novel isolate showed highest similarity to Saccharicrinis fermentans DSM 9555T (94.0 %) and Saccharicrinis carchari SS12T (92.7 %). Strain Y11T was a Gram-stain-negative, rod-shaped, non-endospore-forming, yellow-pigmented bacterium and was able to hydrolyse agar weakly. It was catalase-negative, oxidase-positive, facultatively anaerobic and motile by gliding. Optimal growth occurred at 28-30 °C, at pH 7.0-7.5 and in the presence of 2-3 % (w/v) NaCl. The DNA G+C content was 34.4 mol%. The strain contained MK-7 as the prevalent menaquinone. The major cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0 and C15 : 1ω6c. The predominant polar lipids were phosphatidylethanolamine and two unknown lipids. Data from the present polyphasic taxonomic study clearly place the strain as representing a novel species within the genus Saccharicrinis, for which the name Saccharicrinis marinus sp. nov. is proposed. The type strain is Y11T ( = CICC10837T = KCTC42400T). PMID:26297337

  12. Microsatellite genotypes reveal some long distance gene flow in Perkinsus marinus, a major pathogen of eastern oysters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As the agent of Dermo disease, Perkinsus marinus causes significant mortality and reduced fecundity in host populations. Passive dispersal of P. marinus between hosts subjects parasite movements to control by water currents in estuarine systems, potentially limiting connectivity among parasite popul...

  13. Natural and cultured populations of the mangrove oyster Saccostrea palmula from Sinaloa, Mexico, infected by Perkinsus marinus.

    PubMed

    Cáceres-Martínez, Jorge; Ortega, Mauricio García; Vásquez-Yeomans, Rebeca; García, Teresa de Jesús Pineda; Stokes, Nancy A; Carnegie, Ryan B

    2012-07-01

    The mangrove oyster Saccostrea palmula coexists with the pleasure oyster Crassostrea corteziensis in coastal lagoons of northwest Mexico. Recent discovery of Perkinsus marinus infecting the pleasure oyster in the region prompted evaluation of S. palmula as an alternative P. marinus host. An analysis to determine the possible presence of P. marinus in natural and cultured populations of S. palmula at four coastal lagoons in Sinaloa, Mexico was carried out during October-November 2010. Tissues from apparently healthy S. palmula were evaluated using Ray's fluid thioglycollate method (RFTM), which revealed a Perkinsus sp. to be present in all four locations at 6.7-20.0% prevalence. Histopathological analysis of these specimens showed tissue alterations and parasite forms consistent with moderate P. marinus infection, which was confirmed by ribosomal non-transcribed spacer (NTS)-based PCR assays on DNA samples from oysters positive by RFTM and histology. DNA sequencing of amplified NTS fragments (307 bp) produced a sequence 98-100% similar to GenBank-deposited sequences of the NTS from P. marinus. Fluorescent in situ hybridization for Perkinsus spp. and P. marinus corroborated the PCR results, showing clear hybridization of P. marinus in host tissues. This is the first record of P. marinus infecting a species from genus Saccostrea and the first record of the parasite from coastal lagoons in Sinaloa, Mexico. PMID:22465628

  14. COMPARISON OF IN VITRO-CULTURED AND WILD-TYPE PERKINSUS MARINUS III. FECAL ELIMINATION AND ITS ROLE IN TRANSMISSION

    EPA Science Inventory

    Perkinsus marinus, a pathogen of the eastern oyster Crassostrea virginica, is transmitted directly among oysters. Previous studies found viable P. marinus parasites in the feces and
    pseudofeces of oysters within hours of injection with parasites, suggesting that the parasite ...

  15. Thermally Induced Leakage from Vibrio marinus, an Obligately Psychrophilic Marine Bacterium1

    PubMed Central

    Haight, Roger D.; Morita, Richard Y.

    1966-01-01

    Haight, Rodger D. (Oregon State University, Corvallis), and Richard Y. Morita. Thermally induced leakage from Vibrio marinus, an obligately psychrophilic bacterium. J. Bacteriol. 92:1388–1393. 1966.—Leakage of various cellular components into the surrounding menstruum occurred when Vibrio marinus was subjected to temperatures above 20 C (organism's maximal growth temperature). These materials, listed in decreasing rates of leakage, were identified as protein, deoxyribonucleic acid, ribonucleic acid, and amino acids. The amount of polar amino acids increased as the time and temperature of heat treatment were increased, whereas the nonpolar amino acids decreased. The ribonucleic acid in the supernatant fluid resulting from heat treatment was both polymeric and nonpolymeric. Leakage of cellular components may be one of the reasons that V. marinus MP-1 loses viability when exposed to temperatures above its maximal temperature for growth. PMID:5924270

  16. The complete genome sequence of Staphylothermus marinus reveals differences in sulfur metabolism among heterotrophic Crenarchaeota

    SciTech Connect

    Anderson, iain J.; Dharmarajan, Lakshmi; Rodriguez, Jason; Hooper, Sean; Porat, Iris; Ulrich, Luke E.; Elkins, James G.; Mavromatis, Kostas; Sun, Hui; Land, Miriam; Lapidus, Alla; Lucas, Susan; Barry, Kerrie; Huber, Harald; Zhulin, Igor B.; Whitman, William B.; Mukhopadhyay, Biswarup; Woese, Carl; Bristow, James; Kyrpides, Nikos

    2008-09-05

    Staphylothermus marinus is an anaerobic, sulfur-reducing peptide fermenter of the archaeal phylum Crenarchaeota. It is the third heterotrophic, obligate sulfur reducing crenarchaeote to be sequenced and provides an opportunity for comparative analysis of the three genomes. The 1.57 Mbp genome of the hyperthermophilic crenarchaeote Staphylothermus marinus has been completely sequenced. The main energy generating pathways likely involve 2-oxoacid:ferredoxin oxidoreductases and ADP-forming acetyl-CoA synthases. S. marinus possesses several enzymes not present in other crenarchaeotes including a sodium ion-translocating decarboxylase likely to be involved in amino acid degradation. S. marinus lacks sulfur-reducing enzymes present in the other two sulfur-reducing crenarchaeotes that have been sequenced - Thermofilum pendens and Hyperthermus butylicus. Instead it has three operons similar to the mbh and mbx operons of Pyrococcus furiosus, which may play a role in sulfur reduction and/or hydrogen production. The two marine organisms, S. marinus and H. butylicus, possess more sodium-dependent transporters than T. pendens and use symporters for potassium uptake while T. pendens uses an ATP-dependent potassium transporter. T. pendens has adapted to a nutrient-rich environment while H. butylicus is adapted to a nutrient-poor environment, and S. marinus lies between these two extremes. The three heterotrophic sulfur-reducing crenarchaeotes have adapted to their habitats, terrestrial vs. marine, via their transporter content, and they have also adapted to environments with differing levels of nutrients. Despite the fact that they all use sulfur as an electron acceptor, they are likely to have different pathways for sulfur reduction.

  17. Isolation and characterization of a human intestinal bacterium, Eubacterium sp. ARC-2, capable of demethylating arctigenin, in the essential metabolic process to enterolactone.

    PubMed

    Jin, Jong-Sik; Zhao, Yu-Feng; Nakamura, Norio; Akao, Teruaki; Kakiuchi, Nobuko; Hattori, Masao

    2007-05-01

    Plant lignans, such as pinoresinol diglucoside, secoisolariciresinol diglucoside and arctiin, are metabolized to mammalian lignans, enterolactone or enterodiol, by human intestinal bacteria. Their metabolic processes include deglucosylation, ring cleavage, demethylation, dehydroxylation and oxidation. Here we isolated an intestinal bacterium capable of demethylating arctigenin, an aglycone of arctiin, to 2,3-bis(3,4-dihydroxybenzyl)butyrolactone (1) from human feces, and identified as an Eubacterium species (E. sp. ARC-2), which is similar to Eubacterium limosum on the basis of morphological and biochemical properties and 16S rRNA gene sequencing. By incubating with E. sp. ARC-2, arctigenin was converted to 1 through stepwise demethylation. Demethylation of arctigenin by E. sp. ARC-2 was tetrahydrofolate- and ATP-dependent, indicating that the reaction was catalyzed by methyltransferase. Moreover, E. sp. ARC-2 transformed secoisolariciresinol to 2,3-bis(3,4-dihydroxybenzyl)-1,4-butanediol by demethylation. PMID:17473433

  18. Electrical responses of rods in the retina of Bufo marinus

    PubMed Central

    Cervetto, L.; Pasino, E.; Torre, V.

    1977-01-01

    1. Intracellular responses to flashes and steps of light have been recorded from the outer segment and the cell body of rods in the retina of the Bufo marinus. The identification of the origin of recorded responses has been confirmed by intracellular marking. 2. Responses to flashes delivered in darkness or superimposed on a background were analysed. Responses recorded from outer segments conform to the principle of `spectral univariance'. The shape of the response is not affected by enlarging the spot diameter from 150 to 1000 μm. 3. The membrane potential measured in darkness at the outer segments varied from -15 to -25 mV. Injection of steady hyperpolarizing currents increases the size of the response to light; depolarizing currents reduce the response. The mean value of the input resistance is 97 ± 30 MΩ in darkness and increases by 20-30% during illumination. 4. The responses obtained from the cell body of rods have the same shape, time course and spectral sensitivity of those recorded at the outer segment. Injection of steady current at the cell body produces different effects than at the outer segment: hyperpolarizing currents reduce the amplitude of the response to light; depolarizing currents increase the response. 5. The experimental data are fitted according to a model similar to that used to describe the responses of turtle cones (Baylor & Hodgkin, 1974; Baylor, Hodgkin & Lamb, 1974a, b). 6. The model reproduces the electrical responses of the rod outer segment to a variety of stimuli: (a) brief flashes and steps of light in dark adapted conditions; (b) bright flashes superimposed on background illuminations; (c) pairs of flashes delivered at different time intervals. Responses to hyperpolarizing steps of current are also reproduced by the model. ImagesABCD PMID:406383

  19. Salt sensitivity and hydration behavior of the toad, Bufo marinus.

    PubMed

    Maleek, R; Sullivan, P; Von Seckendorff Hoff, K; Baula, V; Hillyard, S D

    1999-11-01

    Toads, Bufo marinus, were placed on laboratory tissue saturated with water or with hyperosmotic (250 or 500 mM NaCl or KCl) solutions, and their behavior was observed for 5 min. Toads placed on water initially allowed their ventral skin to touch the surface without abducting the hind limbs. During this "seat patch down" (SPD) behavior toads appeared to be evaluating the suitability of a hydration source prior to initiating "water absorption response" (WR) behavior with the hind limbs fully abducted and the ventral skin pressed to the moist surface. Toads dehydrated by more than 10% showed significantly shorter periods of SPD behavior and initiated WR behavior more frequently than did hydrated toads. Dehydrated toads placed on 250 mM NaCl initiated WR behavior in only 18% of the trials, but spent significantly more time showing SPD behavior than they did on water, indicating that this concentration is marginally acceptable to them. Recordings from spinal nerve #6 showed an increase in activity when 250 mM NaCl or KCl solutions were perfused over the outer surface of the ventral skin. The response to KCl was significantly greater than NaCl. The addition of 10 microM amiloride to 250 mM NaCl resulted in a higher frequency of WR behavior and reversibly inhibited the neural response to 250 mM NaCl. These results suggest that epithelial Na+ channels in the skin serve a sensory function in this species. Neither the hydrated nor dehydrated toads initiated WR behavior on 250 or 500 mM KCl solutions, indicating that toads have a lower tolerance of K+ than of Na+ salts. PMID:10604846

  20. In vitro dihydrouridine formation by tRNA dihydrouridine synthase from Thermus thermophilus, an extreme-thermophilic eubacterium.

    PubMed

    Kusuba, Hiroaki; Yoshida, Takeshi; Iwasaki, Eri; Awai, Takako; Kazayama, Ai; Hirata, Akira; Tomikawa, Chie; Yamagami, Ryota; Hori, Hiroyuki

    2015-12-01

    Dihydrouridine (D) is formed by tRNA dihydrouridine synthases (Dus). In mesophiles, multiple Dus enzymes bring about D modifications at several positions in tRNA. The extreme-thermophilic eubacterium Thermus thermophilus, in contrast, has only one dus gene in its genome and only two D modifications (D20 and D20a) in tRNA have been identified. Until now, an in vitro assay system for eubacterial Dus has not been reported. In this study, therefore, we constructed an in vitro assay system using purified Dus. Recombinant T. thermophilus Dus lacking bound tRNA was successfully purified. The in vitro assay revealed that no other factors in living cells were required for D formation. A dus gene disruptant (Δdus) strain of T. thermophilus verified that the two D20 and D20a modifications in tRNA were derived from one Dus protein. The Δdus strain did not show growth retardation at any temperature. The assay system showed that Dus modified tRNA(Phe) transcript at 60°C, demonstrating that other modifications in tRNA are not essential for Dus activity. However, a comparison of the formation of D in native tRNA(Phe) purified from the Δdus strain and tRNA(Phe) transcript revealed that other tRNA modifications are required for D formation at high temperatures. PMID:26112661

  1. Protease activity in the plasma of American oysters, Crassostrea virginica, experimentally infected with the protozoan parasite Perkinsus marinus.

    PubMed

    Muñoz, P; Vance, K; Gómez-Chiarri, M

    2003-10-01

    Perkinsus marinus is responsible for disease and mortality of the American oyster, Crassostrea virginica. To investigate the interactions between P. marinus and oyster hemocytes, protease activity was measured in plasma of oysters collected 4 hr, 24 hr, 4 days, and 2 mo after experimental infection with P. marinus. A significant increase in protease activity was observed in oyster plasma 4 hr after injection with P. marinus, followed by a sharp decrease within 24 hr. Gelatin-impregnated gel electrophoresis showed the presence of 2 major bands (60 and 112 kDa) and 3 less prevalent bands (35, 92, and 200 kDa) with metalloproteinaselike activity in the plasma of noninfected oysters. Additional bands in the 40- to 60-kDa range, corresponding to P. marinus serine proteases, were observed in oyster plasma at early time points after infection. A transient, but significant, decrease in the activity of oyster metalloproteinases was observed at early time points after infection. Coincubation of oyster plasma with P. marinus extracellular products resulted in a decrease in oyster metalloproteinases and several P. marinus proteases. This study provides insights into the role of proteases in the pathogenesis of Dermo disease. PMID:14627141

  2. Minimal sulfur requirement for growth and sulfur-dependent metabolism of the hyperthermophilic archaeon Staphylothermus marinus

    PubMed Central

    Hao, Xiaolei; Ma, Kesen

    2003-01-01

    Staphylothermus marinus is an anaerobic hyperthermophilic archaeon that uses peptides as carbon and energy sources. Elemental sulfur (S°) is obligately required for its growth and is reduced to H2S. The metabolic functions and mechanisms of S° reduction were explored by examining S°-dependent growth and activities of key enzymes present in this organism. All three forms of S° tested—sublimed S°, colloidal S° and polysulfide—were used by S. marinus, and no other sulfur-containing compounds could replace S°. Elemental sulfur did not serve as physical support but appeared to function as an electron acceptor. The minimal S° concentration required for optimal growth was 0.05% (w/v). At this concentration, there appeared to be a metabolic transition from H2 production to S° reduction. Some enzymatic activities related to S°-dependent metabolism, including sulfur reductase, hydrogenase, glutamate dehydrogenase and electron transfer activities, were detected in cell-free extracts of S. marinus. These results indicate that S° plays an essential role in the heterotrophic metabolism of S. marinus. Reducing equivalents generated by the oxidation of amino acids from peptidolysis may be transferred to sulfur reductase and hydrogenase, which then catalyze the production of H2S and H2, respectively. PMID:15803665

  3. Perkinsus marinus superoxide dismutase 2 (PmSOD2) localizes to single-membrane subcellular compartments

    SciTech Connect

    Fernandez-Robledo, Jose A.; Schott, Eric J.; Vasta, Gerardo R.

    2008-10-17

    Perkinsus marinus (Phylum Perkinsozoa), a protozoan parasite of oysters, is considered one of the earliest diverging groups of the lineage leading to dinoflagellates. Perkinsus trophozoites are phagocytosed by oyster hemocytes, where they are likely exposed to reactive oxygen species. As part of its reactive oxygen detoxifying pathway, P. marinus possesses two iron-cofactored SOD (PmSOD1 and PmSOD2). Immunoflourescence analysis of P. marinus trophozoites and gene complementation in yeast revealed that PmSOD1 is targeted to the mitochondria. Surprisingly, although PmSOD2 is characterized by a bipartite N-terminus extension typical of plastid targeting, in preliminary immunofluorescence studies it was visualized as punctuate regions in the cytoplasm that could not be assigned to any organelle. Here, we used immunogold electron microscopy to examine the subcellular localization PmSOD2 in P. marinus trophozoites. Gold grains were mostly associated with single-membrane vesicle-like structures, and eventually, localized to electron-dense, apparently amorphous material present in the lumen of a larger, unique compartment. The images suggested that PmSOD2 is targeted to small vesicles that fuse and/or discharge their content into a larger compartment, possibly the large vacuole typical of the mature trophozoites. In light of the in silico targeting prediction, the association of PmSOD2 with single-membrane compartments raises interesting questions regarding its organellar targeting, and the nature of a putative relic plastid in Perkinsus species.

  4. Clonal population structures are derived from various population processes in the protistan oyster parasite Perkinsus marinus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Population genetic analysis of genotypes comprised of seven microsatellite loci revealed clonal genetic patterns in each of four populations of the protistan estuarine parasite Perkinsus marinus. Each locus was amplified directly from DNA extracted from infected oysters collected from four geographi...

  5. High efficiency of meiotic gynogenesis in sea lamprey Petromyzon marinus

    USGS Publications Warehouse

    Rinchard, J.; Dabrowski, K.; Garcia-Abiado, M. -A.

    2006-01-01

    Induction of androgenesis and gynogenesis by applying a pressure (PS) or heat shock (HS) to double the haploid chromosomal set results in progenies possessing only chromosomes from a single parent. This has never been accomplished in representatives of Agnatha. The objective of this study was to induce gynogenesis and androgenesis in sea lamprey Petromyzon marinus. For gynogenesis experiments, ultraviolet (UV)-irradiated sperm was used to activate sea lamprey eggs and HS or PS were applied to inhibit the second meiotic division and consequently induce diploidy in the embryos. The UV irradiation of immobilized sperm was performed for 1 min at 1,719 J m-2. HS of 35 ?? 1??C for 2 min and PS of 9,000 psi for 4 min were applied at different times after egg activation (8, 12, 20, and 24 min or 8, 16, and 24 min for HS or PS, respectively). Regardless of the induction time of the HS, survivals at pre-hatching stage were similar. In contrast, PS applied 8 min after activation appears to increase survival rate of pre-hatched embryos in comparison to 16 and 24 min after activation. In control groups, without shock treatment (no diploidization), there were no survivors. All deformed, gynogenetic embryos were confirmed to be haploids and died prior to burying themselves in the sand. We confirmed by flow cytometry that progenies produced using both shock methods surviving to the next stage, burying in the substrate, were diploid gynogenetic. For the androgenesis experiments, UV-irradiated eggs (1,719 J m-2 for 1 min) were fertilized with non-treated sperm and HS was applied to restore diploidy of the eggs. Several attempts have been made to optimize the parameters used. HS of 35 ?? 1??C was applied 110, 140, 170, 200, and 230 min after activation for 2 min. Low yields of androgens were obtained and all animals died within a week after hatching. These techniques will allow to establish meiotic gynogenetic lines of sea lamprey for determining sex differentiation in this species

  6. An evolutionary legacy of sex and clonal reproduction in the protistan oyster parasite Perkinsus marinus.

    PubMed

    Thompson, Peter C; Rosenthal, Benjamin M; Hare, Matthew P

    2011-04-01

    Perkinsus marinus, a protozoan parasite of the eastern oyster Crassostrea virginica, causes Dermo disease which limits fecundity and causes high mortality in host populations. The long-term efficacy of management strategies for suppressing this disease in both aquaculture and restoration settings depends on the potential rate of evolutionary response by P. marinus. Sexual reproduction has never been demonstrated in vitro or in previous population genetic studies. We developed high resolution microsatellite markers and amplified alleles directly from infected oyster genomic DNA. Of 336 infected oysters from four populations between Massachusetts and Florida, 129 (48%) appeared to be infected with a single parasite genotype and were subjected to population genetic analyses assuming diploidy. The great diversity of multilocus genotypes observed is incompatible with strictly clonal reproduction. Substantial heterozygote deficits in three populations suggest that sexual reproduction often involves inbreeding. At the same time, significant multilocus linkage disequilibrium occurred in most sampled populations, and several genotypes were sampled repeatedly in each of two populations, indicating that asexual reproduction also occurs in P. marinus populations. Interestingly, where this parasite has recently expanded its range, lower strain diversity, significant heterozygote excess, and highly heterozygous multilocus genotypes suggests clonal propagation of recent recombinants. Taken together, these data suggest that P. marinus employs multiple reproductive modes, and that over the short term, selection acts upon independent parasite lineages rather than upon individual loci in a cohesive, interbreeding population. Nevertheless, high genotypic diversity is the evolutionary legacy of sex in P. marinus. Anthropogenic movement of infected oysters may increase outcrossing opportunities, potentially facilitating rapid evolution of this parasite. PMID:21256249

  7. PROGRESSION OF DISEASES CAUSED BY THE OYSTER PARASITES, PERKINSUS MARINUS AND HAPLOSPORIDIUM NELSONI IN CRASSOSTREA VIRGINICA ON CONSTRUCTED INTERTIDAL REEFS

    EPA Science Inventory

    The progression of diseases caused by the oyster parasites, Perkinsus marinus and Haplosporidium nelsoni, were evaluated by periodic sampling (May 1994 - December 1995) of oysters, Crassostrea virginica, on an artificial reef located in the Piankatank River, Virginia. The infecti...

  8. Numerical Quantification of Perkinsus Marinus in the American Oyster Crassostrea virginicata (Gmelin 1791) (Mollusca: Bivalvia) by Modern Stereology

    EPA Science Inventory

    Species of Perkinsus are responsible for high mortalities of bivalve molluscs world-wide. Techniques to accurately estimate parasites in tissues are required to improve understanding of perkinsosis. This study quantifies the number and tissue distribution of Perkinsus marinus in ...

  9. Structures of PmSOD1 and PmSOD2, two superoxide dismutases from the protozoan parasite Perkinsus marinus.

    PubMed

    Asojo, Oluwatoyin A; Schott, Eric J; Vasta, Gerardo R; Silva, Abelardo M

    2006-11-01

    Perkinsus marinus, a facultative intracellular parasite of the eastern oyster Crassostrea virginica, is responsible for mass mortalities of oyster populations. P. marinus trophozoites survive and proliferate within oyster hemocytes, invading most tissues and fluids, thus causing a systemic infection that eventually kills the host. The phagocytosis of P. marinus trophozoites lacks a respiratory burst, suggesting that the parasite has mechanisms that actively abrogate the host's oxidative defense responses. One mechanism and the first line of defense against oxidative damage is the dismutation of superoxide radical to molecular oxygen and hydrogen peroxide by superoxide dismutases (SODs). P. marinus possesses two iron-cofactored SODs, PmSOD1 and PmSOD2. Here, the crystallization and X-ray structures of both PmSOD1 and PmSOD2 are presented. PMID:17077482

  10. Polymorphism at the ITS and NTS Loci of Perkinsus marinus isolated from cultivated oyster Crassostrea corteziensis in Nayarit, Mexico and phylogentic relationship to P. marinus along the Atlantic Coast.

    PubMed

    Escobedo-Fregoso, C; Arzul, I; Carrasco, N; Gutiérrez-Rivera, J N; Llera-Herrera, R; Vázquez-Juárez, R

    2015-04-01

    Prevalence of the protozoan Perkinsus spp. in the gills of the pleasure oyster Crassostrea corteziensis from two estuaries in Nayarit, Mexico, was measured. The protozoan was identified by PCR amplification of the internal transcribed spacer (ITS) region of the rDNA of Perkinsus spp. The pathogen was found in 92% of oysters from Boca de Camichín and 77% of oysters from Pozo Chino. ITS sequences characterized from C. corteziensis showed 96-100% similarity to Perkinsus marinus. The most frequent ITS sequence (GenBank JQ266236) had 100% identity with the ITS locus of P. marinus from New Jersey, Maryland, South Carolina and Texas, and the second most frequent observed sequence (GenBank JQ266240) was 100% identical to ITS sequences of P. marinus from New Jersey, South Carolina, Louisiana, and Bahía Kino, Sonora, Mexico. The 14 sequences from the non-transcribed spacer (NTS) showed 98% similarity to P. marinus from Texas. The most frequent polymorphism identified was at nucleotide 446 of the ITS region; however, the NTS showed the highest nucleotide diversity, thereby suggesting that this region is suitable for genotype identification. Moreover, the most conserved ITS marker is better for species-specific diagnosis. Both the ITS and NTS sequences of P. marinus obtained from C. corteziensis were grouped in two clades, identifying two allelic variants of P. marinus. PMID:23607743

  11. Exposure to a putative alarm cue reduces downstream drift in larval sea lamprey Petromyzon marinus in the laboratory.

    PubMed

    Wagner, C M; Kierczynski, K E; Hume, J B; Luhring, T M

    2016-09-01

    An experimental mesocosm study suggested larval sea lamprey Petromyzon marinus detect and respond to an alarm cue released by dead adult conspecifics. Larvae exhibited a reduced tendency to move downstream when exposed to the cue and were less likely to move under continuous v. pulsed exposure. These findings support the hypothesis that short-term exposure to the alarm cue would probably result in retraction into the burrow, consistent with the blind, cryptic lifestyle of the larval P. marinus. PMID:27456088

  12. An eDNA assay for Irish Petromyzon marinus and Salmo trutta and field validation in running water.

    PubMed

    Gustavson, M S; Collins, P C; Finarelli, J A; Egan, D; Conchúir, R Ó; Wightman, G D; King, J J; Gauthier, D T; Whelan, K; Carlsson, J E L; Carlsson, J

    2015-11-01

    This pilot study presents an environmental DNA (eDNA) assay for sea lamprey Petromyzon marinus and brown trout Salmo trutta, two species of economic and conservation importance in the Republic of Ireland. The results demonstrate the effectiveness of eDNA for assessing presence of low-abundance taxa (here, P. marinus) for environmental managers, and they highlight the potential for assessing relative abundance of rare or invasive freshwater species. PMID:26377304

  13. Effects of triclosan on growth, viability and fatty acid synthesis of the oyster protozoan parasite Perkinsus marinus.

    PubMed

    Lund, Eric D; Soudant, Philippe; Chu, Fu-Lin E; Harvey, Ellen; Bolton, Stephanie; Flowers, Adolph

    2005-11-28

    Perkinsus marinus, a protozoan parasite of the Eastern oyster Crassostrea virginica, has severely impacted oyster populations from the Mid-Atlantic region to the Gulf of Mexico coast of North America for more than 30 yr. Although a chemotherapeutic treatment to reduce or eliminate P. marinus from infected oysters would be useful for research and hatchery operations, an effective and practical drug treatment does not currently exist. In this study, the antimicrobial drug triclosan 5-chloro-2-(2,4 dichlorophenoxy) phenol, a specific inhibitor of Fab1 (enoyl-acyl-carrier-protein reductase), an enzyme in the Type II class of fatty acid synthetases, was tested for its effects on viability, proliferation and fatty acid synthesis of in vitro-cultured P. marinus meronts. Treatment of P. marinus meront cell cultures with concentrations of > or = 2 microM triclosan at 28 degrees C (a temperature favorable for parasite proliferation) for up to 6 d stopped proliferation of the parasite. Treatment at > or = 5 microM at 28 degrees C greatly reduced the viability and fatty acid synthesis of meront cells. Oyster hemocytes treated with > or = 20 microM triclosan exhibited no significant (p < 0.05) reduction in viability relative to controls for up to 24 h at 13 degrees C. P. marinus meronts exposed to > or = 2 microM triclosan for 24 h at 13 degrees C exhibited significantly (p < 0.05) lower viability relative to controls. Exposure of P. marinus meronts to triclosan concentrations of > or = 20 microM resulted in > 50% mortality of P. marinus cells after 24 h. These results suggest that triclosan may be effective in treating P. marinus-infected oysters. PMID:16408837

  14. Factors associated with the prevalence of Perkinsus marinus in Crassostrea virginica from the southern Gulf of Mexico.

    PubMed

    Gullian-Klanian, M; Herrera-Silveira, J A; Rodríguez-Canul, R; Aguirre-Macedo, L

    2008-05-01

    The protozoan Perkinsus marinus is considered the most important pathogen of the eastern oyster Crassostrea virginica, causing high mortality in natural and farmed oysters on the Atlantic coast of the US. In Mexico, no serious P. marinus epizootic has been reported. This study describes the current state of P. marinus prevalence in Terminos Lagoon (Mexico) associated with environmental factors including salinity, temperature, ammonium, nitrate, nitrite, silica, and phosphorus. In addition, the association of physiological (hemocyte density, protein concentration) and immunological (lysozyme, agglutination) parameters with the infection were studied. The prevalence was significantly different among seasons with mean values of 70, 23, and 7% in the dry (February to May), rainy (June to September) and north-wind (October to January) seasons, respectively. Only light infection intensity (Mackin scale value < 1) was observed. Prevalence of P. marinus was associated with seasonal salinity, phosphorus, and silica variations. Comparisons of oyster health demonstrates that the rainy and north-wind seasons are stressful periods. Redundancy analysis showed that only 34% of the variation in seasonal P. marinus prevalence was explained by protein concentration (21%), lysozyme (12%), and agglutination (1%). Overall, the data suggest that freshwater input associated with high nutrient concentrations during the rainy and north-wind seasons has a strong negative effect on P. marinus prevalence and also influences the oysters' physiology. It is probable that this seasonal stress was responsible for the absence of an epizootic event in Terminos Lagoon. PMID:18590000

  15. Features of rumen and sewage sludge strains of Eubacterium limosum, a methanol- and H2-CO2-utilizing species.

    PubMed Central

    Genthner, B R; Davis, C L; Bryant, M P

    1981-01-01

    Eubacterium limosum was isolated as the most numerous methanol-utilizing bacterium in the rumen fluid of sheep fed a diet in which molasses was a major component (mean most probable number of 6.3 X 10(8) viable cells per ml). It was also isolated from sewage sludge at 9.5 X 10(4) cells per ml. It was not detected in the rumen fluid of a steer on a normal hay-grain diet, although Methanosarcina, as expected, was found at 9.5 X 10(5) cells per ml. The doubling time of E. limosum in basal medium (5% rumen fluid) with methanol as the energy source (37 degree C) was 7 h. Acetate, cysteine, carbon dioxide, and the vitamins biotin, calcium-D-pantothenate, and lipoic acid were required for growth on a chemically defined methanol medium. Acetate, butyrate, and caproate were produced from methanol. Ammonia or each of several amino acids served as the main nitrogen source. Other energy sources included adonitol, arabitol, erythritol, fructose, glucose, isoleucine, lactate, mannitol, ribose, valine, and H2-CO2. The doubling time for growth on H2-CO2 (5% rumen fluid, 37 degree C) was 14 h as compared with 5.2 h for isoleucine and 3.5 h for glucose. The vitamin requirements for growth on H2-CO2 were the same as those for methanol; however, acetate was not required for growth on H2-CO2, although it was necessary for growth on valine, isoleucine, and lactate and was stimulatory to growth on glucose. Acetate and butyrate were formed during growth on H2-CO2, whereas branched-chain fatty acids and ammonia were fermentation products from the amino acids. Heat tolerance was detected, but spores were not observed. The type strain of E. limosum (ATCC 8486) and strain L34, which was isolated from the rumen of a young calf, grew on methanol, H2-CO2, valine, and isoleucine and showed the same requirements for acetate as the freshly isolated strains. PMID:6791591

  16. RNase P RNA from Prochlorococcus marinus: contribution of substrate domains to recognition by a cyanobacterial ribozyme.

    PubMed

    Hess, W R; Fingerhut, C; Schön, A

    1998-07-17

    The molecular organisation of the Prochlorococcus marinus rnpB gene and the catalytic activity of the encoded RNA were characterised. Kinetic parameters for several pre-tRNA substrates were comparable to those from other eubacterial RNase P RNAs, although unusually high cation concentrations were required. The CCA-end of pre-tRNAs is essential for efficient turnover despite the lack of the canonical binding motif in P. marinus RNase P RNA. A trnR gene is located only 38 nt upstream the rnpB 5' end on the complementary strand. This arrangement resembles those in the plastids of Cyanophora and Porphyra but not in any other bacterium. PMID:9708890

  17. Diet composition of the invasive cane toad (Chaunus marinus) on Rota, Northern Mariana Islands

    USGS Publications Warehouse

    Reed, R.N.; Bakkegard, K.A.; Desy, G.E.; Plentovich, S.M.

    2007-01-01

    The cane or marine toad (Chaunus marinus, formerly Bufo marinus) was introduced to the Northern Mariana Islands starting in the 1930s. The effects of this exotic predator on native vertebrates (especially lizards) are largely unknown. We analysed the stomach contents of 336 cane toads collected from the island of Rota, with the goal of estimating the level of toad predation on native vertebrates. Beetles, ants, millipedes, and grasshoppers/crickets comprised the majority of prey classes consumed by toads. The introduced Brahminy blindsnake (Ramphotyphlops braminus; N = 6) and conspecific cane toads (N = 4) were the vertebrates most commonly found in toad stomachs. Skinks (Emoia; N = 2) were the only native vertebrates represented in our sample. The small numbers of nocturnal terrestrial vertebrates native to Rota likely translates to relatively low rates of predation by cane toads on native vertebrates.

  18. Sterilization of sea lampreys (Petromyzon marinus) by immersion in an aqueous solution of bisazir

    USGS Publications Warehouse

    Hanson, Lee H.

    1981-01-01

    Groups of sea lamprey (Petromyzon marinus) eggs fertilized by males previously immersed in an aqueous solution of p,p-bis(1-aziridinyl)-N-methylphosphinothioic amide (bisazir) at concentrations of 10–100 mg/L produced fewer normal, live prolarvae after 15–17 d of incubation than did groups of eggs fertilized by normal males. Mortality of embryos or prolarvae was nearly 100% in groups of eggs fertilized by males that had been immersed in a 50 mg/L solution of bisazir for 4 h or in a 100 mg/L solution for 2 h. The immersion technique appears to be an efficient method of sterilizing large numbers of male sea lampreys for use in a proposed sterile-male-release program.Key words: sea lamprey, Petromyzon marinus; pest control, fish control, sterile-male technique, sterilization, chemosterilants, bisazir, Great Lakes

  19. Cytogenetic evidences of genome rearrangement and differential epigenetic chromatin modification in the sea lamprey (Petromyzon marinus).

    PubMed

    Covelo-Soto, Lara; Morán, Paloma; Pasantes, Juan J; Pérez-García, Concepción

    2014-12-01

    This work explores both the chromatin loss and the differential genome methylation in the sea lamprey (Petromyzon marinus) from a molecular cytogenetic point of view. Fluorescent in situ hybridization experiments on meiotic bivalents and mitotic chromosomes corroborate the chromatin loss previously observed during the development of the sea lamprey and demonstrate that the elimination affects not only to Germ1 sequences but also to the rpt200 satellite DNA and most part of the major ribosomal DNA present on the germinal line. 5-Methylcytosine immunolocation revealed that the GC-rich heterochromatin is highly methylated in the germ line but significantly less in somatic chromosomes. These findings not only support previous observations about genome rearrangements but also give new information about epigenetic changes in P. marinus. The key position of lampreys in the vertebrate phylogenetic tree makes them an interesting taxon to provide relevant information about genome evolution in vertebrates. PMID:25432678

  20. Diversity of Aplochiton Fishes (Galaxiidea) and the Taxonomic Resurrection of A. marinus

    PubMed Central

    Arias, Carlos; Cárdenas, Leyla

    2013-01-01

    Aplochiton is a small genus of galaxiid fishes endemic to Patagonia and the Falkland Islands whose taxonomy is insufficiently resolved. Recent genetic analyses confirmed the existence of only two closely related species, Aplochiton taeniatus and Aplochiton zebra, while a third controversial species, Aplochiton marinus, remained lost to synonymy with A. taeniatus. Using an integrative taxonomy framework, we studied original samples and published sequences from a broad range in western Patagonia and the Falkland Islands, and generated robust species hypotheses based on single-locus (Cytochrome Oxidase subunit I; COI) species-delineation methods and known diagnostic morphological characters analyzed in a multivariate context. Results revealed three distinct evolutionary lineages that morphologically resemble, in important respects, existing nominal species descriptions. Interestingly, the lineage associated with A. marinus was unambiguously identifiable (100% accuracy) both from the genetic and morphological viewpoints. In contrast, the morphology of A. taeniatus and A. zebra overlapped substantially, mainly due to the high variability of A. taeniatus. Discriminant function analysis aided the identification of these species with 83.9% accuracy. Hence, for their unambiguous identification, genetic screening is needed. A. marinus has seldom been documented, and when recorded, it has always been found in sites with clear marine influence. It is possible that only A. marinus preserves a life cycle related to the sea akin to the hypothesized ancestral galaxiid. We did not find evidence of claimed diadromy in A. taeniatus or A. zebra, and, therefore, these should be regarded as freshwater species. Finally, a lack of phylogeographic patterns and overrepresentation of uncommon haplotypes suggested demographic expansions in recent evolutionary time, especially of A. zebra, in line with the hypothesis of large-scale range expansion and lineage spread in western Patagonia. PMID

  1. Acute toxicity of methyl mercury to the larval lamprey, Petromyzon marinus

    SciTech Connect

    Mallatt, J.; Barron, M.G.; McDonough, C.

    1986-08-01

    Mercury compounds pollute many aquatic habitats and are extremely toxic to aquatic organisms. Acute toxicity of waterborne methyl mercury has been studied in several teleost species. Lampreys are taxonomically distant from teleosts and are used for comparative toxicological purposes. Landlocked sea lampreys, Petromyzon marinus, inhabit the Great Lakes region, and their larvae (ammocoetes) burrow in stream sediments. In this study, the authors present toxicity curves for ammocoetes exposed acutely to methyl mercuric chloride solutions. Susceptibility was related to temperature and animal size.

  2. Diversity of Aplochiton fishes (Galaxiidea) and the taxonomic resurrection of A. marinus.

    PubMed

    Alò, Dominique; Correa, Cristián; Arias, Carlos; Cárdenas, Leyla

    2013-01-01

    Aplochiton is a small genus of galaxiid fishes endemic to Patagonia and the Falkland Islands whose taxonomy is insufficiently resolved. Recent genetic analyses confirmed the existence of only two closely related species, Aplochiton taeniatus and Aplochiton zebra, while a third controversial species, Aplochiton marinus, remained lost to synonymy with A. taeniatus. Using an integrative taxonomy framework, we studied original samples and published sequences from a broad range in western Patagonia and the Falkland Islands, and generated robust species hypotheses based on single-locus (Cytochrome Oxidase subunit I; COI) species-delineation methods and known diagnostic morphological characters analyzed in a multivariate context. Results revealed three distinct evolutionary lineages that morphologically resemble, in important respects, existing nominal species descriptions. Interestingly, the lineage associated with A. marinus was unambiguously identifiable (100% accuracy) both from the genetic and morphological viewpoints. In contrast, the morphology of A. taeniatus and A. zebra overlapped substantially, mainly due to the high variability of A. taeniatus. Discriminant function analysis aided the identification of these species with 83.9% accuracy. Hence, for their unambiguous identification, genetic screening is needed. A. marinus has seldom been documented, and when recorded, it has always been found in sites with clear marine influence. It is possible that only A. marinus preserves a life cycle related to the sea akin to the hypothesized ancestral galaxiid. We did not find evidence of claimed diadromy in A. taeniatus or A. zebra, and, therefore, these should be regarded as freshwater species. Finally, a lack of phylogeographic patterns and overrepresentation of uncommon haplotypes suggested demographic expansions in recent evolutionary time, especially of A. zebra, in line with the hypothesis of large-scale range expansion and lineage spread in western Patagonia. PMID

  3. Identification of MMV Malaria Box Inhibitors of Perkinsus marinus Using an ATP-Based Bioluminescence Assay

    PubMed Central

    Alemán Resto, Yesmalie; Fernández Robledo, José A.

    2014-01-01

    “Dermo” disease caused by the protozoan parasite Perkinsus marinus (Perkinsozoa) is one of the main obstacles to the restoration of oyster populations in the USA. Perkinsus spp. are also a concern worldwide because there are limited approaches to intervention against the disease. Based on the phylogenetic affinity between the Perkinsozoa and Apicomplexa, we exposed Perkinsus trophozoites to the Medicines for Malaria Venture Malaria Box, an open access compound library comprised of 200 drug-like and 200 probe-like compounds that are highly active against the erythrocyte stage of Plasmodium falciparum. Using a final concentration of 20 µM, we found that 4 days after exposure 46% of the compounds were active against P. marinus trophozoites. Six compounds with IC50 in the µM range were used to compare the degree of susceptibility in vitro of eight P. marinus strains from the USA and five Perkinsus species from around the world. The three compounds, MMV666021, MMV665807 and MMV666102, displayed a uniform effect across Perkinsus strains and species. Both Perkinsus marinus isolates and Perkinsus spp. presented different patterns of response to the panel of compounds tested, supporting the concept of strain/species variability. Here, we expanded the range of compounds available for inhibiting Perkinsus proliferation in vitro and characterized Perkinsus phenotypes based on their resistance to six compounds. We also discuss the implications of these findings in the context of oyster management. The Perkinsus system offers the potential for investigating the mechanism of action of the compounds of interest. PMID:25337810

  4. Identification of MMV Malaria Box inhibitors of Perkinsus marinus using an ATP-based bioluminescence assay.

    PubMed

    Alemán Resto, Yesmalie; Fernández Robledo, José A

    2014-01-01

    "Dermo" disease caused by the protozoan parasite Perkinsus marinus (Perkinsozoa) is one of the main obstacles to the restoration of oyster populations in the USA. Perkinsus spp. are also a concern worldwide because there are limited approaches to intervention against the disease. Based on the phylogenetic affinity between the Perkinsozoa and Apicomplexa, we exposed Perkinsus trophozoites to the Medicines for Malaria Venture Malaria Box, an open access compound library comprised of 200 drug-like and 200 probe-like compounds that are highly active against the erythrocyte stage of Plasmodium falciparum. Using a final concentration of 20 µM, we found that 4 days after exposure 46% of the compounds were active against P. marinus trophozoites. Six compounds with IC50 in the µM range were used to compare the degree of susceptibility in vitro of eight P. marinus strains from the USA and five Perkinsus species from around the world. The three compounds, MMV666021, MMV665807 and MMV666102, displayed a uniform effect across Perkinsus strains and species. Both Perkinsus marinus isolates and Perkinsus spp. presented different patterns of response to the panel of compounds tested, supporting the concept of strain/species variability. Here, we expanded the range of compounds available for inhibiting Perkinsus proliferation in vitro and characterized Perkinsus phenotypes based on their resistance to six compounds. We also discuss the implications of these findings in the context of oyster management. The Perkinsus system offers the potential for investigating the mechanism of action of the compounds of interest. PMID:25337810

  5. Copper exposure affects hemocyte apoptosis and Perkinsus marinus infection in eastern oysters Crassostrea virginica (Gmelin).

    PubMed

    Foster, Brent; Grewal, Snimar; Graves, Ondrea; Hughes, Francis M; Sokolova, Inna M

    2011-08-01

    Dermo disease in the eastern oyster (Crassostrea virginica) is caused by an intracellular protistan parasite Perkinsus marinus. The progression and outcome of this disease is determined by a complex interplay between the host's immunity and parasite's escape mechanisms, both of which can be influenced by environmental pollutants including heavy metals such as copper (Cu). The goal of the present study was to determine the effects of Cu on the levels of apoptosis (which can serve as an important host defense mechanism) in oyster immune cells (hemocytes) in vitro and in vivo as well as on the establishment of P. marinus infections in vivo. Surprisingly, Cu exerted opposing effects on apoptosis levels of hemocytes in vitro and in vivo, stimulating apoptosis in isolated hemocytes but suppressing it during Cu exposure of whole oysters. The mechanisms of this effect are presently unknown and may be related to the different bioavailability of the metal in vitro and in vivo. As expected, Cu accumulated in oyster soft tissues during in vitro exposure. Unexpectedly, this metal also strongly accumulated in hemolymph plasma which is classically considered isoionic with the surrounding seawater, likely reflecting the presence of soluble Cu-binding proteins in oyster plasma. Cu reduced growth of P. marinus in vitro and greatly reduced infection levels of hemocytes in vivo, presumably by direct toxic effects on the parasite. As a possible parasitic counterbalance, Cu accumulation in the hemocytes was reduced by P. marinus infection, although this reduction was not sufficient to prevent the parasiticidal effects of the heavy metal in vivo. This effect of Cu may be useful as a potential therapeutic against Dermo disease in aquaculture conditions. Overall, this study provides important new insights into the potential role of environmental metals in host-parasite relationships and disease dynamics in C. virginica. PMID:21658453

  6. Perkinsus marinus in pleasure oyster Crassostrea corteziensis from Nayarit, Pacific coast of México.

    PubMed

    Cáceres-Martínez, J; Vásquez-Yeomans, R; Padilla-Lardizábal, G; del Río Portilla, M A

    2008-09-01

    Culture of the pleasure oyster Crassostrea corteziensis is emerging as an alternative to the Pacific oyster (Crassostrea gigas) for oyster producers, who face severe mortalities since 1997 in Northwest México. For determining the health status of this species, we conducted a histopathological analysis of cultured populations from two estuaries in the Pacific coast of México. Macroscopical analysis revealed animals with transparent and retracted mantle. Histopathological analysis of these specimens showed tissue alterations and parasitic forms consistent with Perkinsus sp. infection. Stages of the parasite identified included tomont and trophozoites with an eccentric vacuole characteristic of Perkinsus spp. Pieces of tissues of infected oysters were incubated in Fluid Thioglycollate Medium (FTM) resulting in blue-black hypnospores after incubation. The identity of the parasite was confirmed by species specific PCR-based assay in DNA samples from oysters, tissue fractions from FTM cultures, and deparaffined samples with Perkinsus-like parasite detected by histology. Sequencing of positive amplified fragments (307bp) showed a sequence similar to Perkinsus marinus strain TXsc NTS ribosomal RNA gene (100% coverage and 98% identity, GenBank Accession No. AF497479.1) and to P. marinus, Genomic DNA, (100% coverage and 97% identity, GenBank Accession No. S78416.1). The prevalence of P. marinus varied from 1 to 5% in Boca del Camichín and from 1 to 6% in Pozo Chino. In general, the intensity of infection was moderate. The infection was observed in oysters from 31 to 110mm of shell length. This is the first record of P. marinus in oysters from the North America Pacific coast and the first record in C. corteziensis. The origin of this parasite in the area is unknown, but it may be associated to introductions of Crassostrea virginica from the East coast of United States of America or Gulf of México. PMID:18423484

  7. The influence of sediment type on the distribution of the lesser sandeel, Ammodytes marinus

    NASA Astrophysics Data System (ADS)

    Wright, P. J.; Jensen, H.; Tuck, I.

    2000-12-01

    The lesser sandeel Ammodytes marinus ( Raitt, 1934) is an important component of the North Sea ecosystem and the subject of the largest single species fishery in this region. However, little is known about the distribution of this species outside the areas where they are fished. This study examines the physical characteristics of the habitat of A. marinus in an attempt to predict the distribution of this species. The characteristics and topography of sandeel habitat were described from video observations. Data on abundance, sediment characteristics and depth were collected from benthic sampling programmes around the Shetland Isles. These data were used in a general additive model framework (GAM) to examine the relative significance of physical factors in influencing distribution. This analysis found that A. marinus were absent from sediments with a silt/clay content of >10% and densities declined between fractions from 2 to 10%. The apparent dislike for fine sediments was examined further by means of sediment choice experiments. These experiments confirmed the importance of the fine particle fraction in limiting distribution and indicated that sandeels would not be expected to inhabit such areas. Given the constraints of sediment requirements, densities of sandeels in benthic samples appeared to be influenced by water depth.

  8. Pallial mucus of the oyster Crassostrea virginica regulates the expression of putative virulence genes of its pathogen Perkinsus marinus.

    PubMed

    Pales Espinosa, Emmanuelle; Corre, Erwan; Allam, Bassem

    2014-04-01

    Perkinsus marinus is a pathogen responsible for severe mortalities of the eastern oyster Crassostrea virginica along the East and Gulf coasts of the United States. When cultivated, the pathogenicity of this microorganism decreases significantly, hampering the study of its virulence factors. Recent investigations have shown a significant increase of the in vivo virulence of P. marinus exposed to oyster pallial mucus. In the current study, we investigated the effect of pallial mucus on P. marinus gene expression compared with cultures supplemented with oyster digestive extracts or with un-supplemented cultures. In parallel, parasite cells cultured under these three conditions were used to challenge oysters and to assess virulence in vivo. Perkinsus marinus mRNA sequencing was performed on an Illumina GAIIX sequencer and data were analysed using the Tuxedo RNAseq suite for mapping against the draft P. marinus genome and for differential expression analysis. Results showed that exposure of P. marinus to mucus induces significant regulation of nearly 3,600 transcripts, many of which are considered as putative virulence factors. Pallial mucus is suspected to mimic internal host conditions, thereby preparing the pathogen to overcome defense factors before invasion. This hypothesis is supported by significant regulation in several antioxidant proteins, heat shock proteins, protease inhibitors and proteasome subunits. In addition, mucus exposure induced the modulation of several genes known to affect immunity and apoptosis in vertebrates and invertebrates. Several proteases (proteolysis) and merozoite surface proteins (cell recognition) were also modulated. Overall, these results provide a baseline for targeted, in depth analysis of candidate virulence factors in P. marinus. PMID:24560916

  9. Thyroid hormone and retinoid X receptor function and expression during sea lamprey (Petromyzon marinus) metamorphosis.

    PubMed

    Manzon, Lori A; Youson, John H; Holzer, Guillaume; Staiano, Leopoldo; Laudet, Vincent; Manzon, Richard G

    2014-08-01

    Sea lampreys (Petromyzon marinus) are members of the ancient class Agnatha and undergo a metamorphosis that transforms blind, sedentary, filter-feeding larvae into free-swimming, parasitic juveniles. Thyroid hormones (THs) appear to be important for lamprey metamorphosis, however, serum TH concentrations are elevated in the larval phase, decline rapidly during early metamorphosis and remain low until metamorphosis is complete; these TH fluctuations are contrary to those of other metamorphosing vertebrates. Moreover, thyroid hormone synthesis inhibitors (goitrogens) induce precocious metamorphosis and exogenous TH treatments disrupt natural metamorphosis in P. marinus. Given that THs exert their effects by binding to TH nuclear receptors (TRs) that often act as heterodimers with retinoid X receptors (RXRs), we cloned and characterized these receptors from P. marinus and examined their expression during metamorphosis. Two TRs (PmTR1 and PmTR2) and three RXRs (PmRXRs) were isolated from P. marinus cDNA. Phylogenetic analyses group the PmTRs together on a branch prior to the gnathostome TRα/β split. The three RXRs also group together, but our data indicated that these transcripts are most likely either allelic variants of the same gene locus, or the products of a lamprey-specific duplication event. Importantly, these P. marinus receptors more closely resemble vertebrate as opposed to invertebrate chordate receptors. Functional analysis revealed that PmTR1 and PmTR2 can activate transcription of TH-responsive genes when treated with nanomolar concentrations of TH and they have distinct pharmacological profiles reminiscent of vertebrate TRβ and TRα, respectively. Also similar to other metamorphosing vertebrates, expression patterns of the PmTRs during lamprey metamorphosis suggest that PmTR1 has a dynamic, tissue-specific expression pattern that correlates with tissue morphogenesis and biochemical changes and PmTR2 has a more uniform expression pattern. This TR

  10. Jeotgalibacillus alimentarius gen. nov., sp. nov., a novel bacterium isolated from jeotgal with L-lysine in the cell wall, and reclassification of Bacillus marinus Rüger 1983 . as mMrinibacillus marinus gen nov., comb. nov.

    PubMed

    Yoon, J H; Weiss, N; Lee, K C; Lee, I S; Kang, K H; Park, Y H

    2001-11-01

    A moderately halophilic, round-endospore-forming bacterium (strain YKJ-13T) was isolated from jeotgal, a traditional Korean fermented seafood, and studied by a polyphasic taxonomic approach. This organism was related to the phylogenetic clade comprising members of Bacillus rRNA group 2 and formed a cluster with Bacillus marinus with a bootstrap fidelity value of 93.6%. The peptidoglycan type was A1alpha linked directly through L-Lys. Based on cell morphology, peptidoglycan type and phylogeny, strain YKJ-13T, together with B. marinus, is considered to be a member of Bacillus rRNA group 2. Strain YKJ-13T was also characterized by having MK-7 and MK-8 as the predominant menaquinones and iso-C15:0 as the major fatty acid. The DNA G+C content was 44 mol%. Strain YKJ-13T exhibited a 16S rDNA similarity value of 95.7% with B. marinus DSM 1297T, its closest phylogenetic relative. Levels of 16S rDNA similarity between strain YKJ-13T and other Bacillus spp. were less than 94.2%. Therefore, on the basis of the data presented, the name Jeotgalibacillus alimentarius gen. nov., sp. nov. is proposed for strain YKJ-13T (= KCCM 80002T = JCM 10872T). It is also proposed that B. marinus be reclassified in Marinibacillus gen. nov. as Marinibacillus marinus comb. nov. PMID:11760951

  11. Development of a multiplex PCR for the detection of Haplosporidium nelsoni, Haplosporidium costale and Perkinsus marinus in the eastern oyster (Crassostrea virginica, Gmelin, 1971).

    PubMed

    Penna, M S; Khan, M; French, R A

    2001-12-01

    Haplosporidium costale (SSO), Haplosporidium nelsoni (MSX) and Perkinsus marinus (Dermo) have caused oyster mortality on the North American east coast since the 1950s. Currently, the monitoring of oyster populations for these pathogens depends on histopathology for H. nelsoni, H. costale and the Ray/Mackin assay for P. marinus. In this study we describe the development and optimization of a multiplex polymerase chain reaction (MPCR) for the detection of H. nelsoni, H. costale and P. marinus. In addition, we determine its specificity and sensitivity. The MPCR clearly detects and differentiates the protozoan pathogens. There was no cross-reactivity between these species. The MPCR was able to detect DNA from H. nelsoni as low as 10 fg and P. marinus and H. costale as low as 1 pg. The MPCR allows for the detection of H. nelsoni, H. costale and P. marinus in a single PCR reaction. PMID:11851382

  12. Mutual Cross-Feeding Interactions between Bifidobacterium longum subsp. longum NCC2705 and Eubacterium rectale ATCC 33656 Explain the Bifidogenic and Butyrogenic Effects of Arabinoxylan Oligosaccharides

    PubMed Central

    Rivière, Audrey; Gagnon, Mérilie; Weckx, Stefan; Roy, Denis

    2015-01-01

    Arabinoxylan oligosaccharides (AXOS) are a promising class of prebiotics that have the potential to stimulate the growth of bifidobacteria and the production of butyrate in the human colon, known as the bifidogenic and butyrogenic effects, respectively. Although these dual effects of AXOS are considered beneficial for human health, their underlying mechanisms are still far from being understood. Therefore, this study investigated the metabolic interactions between Bifidobacterium longum subsp. longum NCC2705 (B. longum NCC2705), an acetate producer and arabinose substituent degrader of AXOS, and Eubacterium rectale ATCC 33656, an acetate-converting butyrate producer. Both strains belong to prevalent species of the human colon microbiota. The strains were grown on AXOS during mono- and coculture fermentations, and their growth, AXOS consumption, metabolite production, and expression of key genes were monitored. The results showed that the growth of both strains and gene expression in both strains were affected by cocultivation and that these effects could be linked to changes in carbohydrate consumption and concomitant metabolite production. The consumption of the arabinose substituents of AXOS by B. longum NCC2705 with the concomitant production of acetate allowed E. rectale ATCC 33656 to produce butyrate (by means of a butyryl coenzyme A [CoA]:acetate CoA-transferase), explaining the butyrogenic effect of AXOS. Eubacterium rectale ATCC 33656 released xylose from the AXOS substrate, which favored the B. longum NCC2705 production of acetate, explaining the bifidogenic effect of AXOS. Hence, those interactions represent mutual cross-feeding mechanisms that favor the coexistence of bifidobacterial strains and butyrate producers in the same ecological niche. In conclusion, this study provides new insights into the bifidogenic and butyrogenic effects of AXOS. PMID:26319874

  13. A cryptic algal group unveiled: a plastid biosynthesis pathway in the oyster parasite Perkinsus marinus.

    PubMed

    Matsuzaki, Motomichi; Kuroiwa, Haruko; Kuroiwa, Tsuneyoshi; Kita, Kiyoshi; Nozaki, Hisayoshi

    2008-06-01

    Plastids are widespread in plant and algal lineages. They are also exploited by some nonphotosynthetic protists, including malarial parasites, to support their diverse modes of life. However, cryptic plastids may exist in other nonphotosynthetic protists, which could be important in studies on the diversity and evolution of plastids. The parasite Perkinsus marinus, which causes mass mortality in oyster farms, is a nonphotosynthetic protist that is phylogenetically related to plastid-bearing dinoflagellates and apicomplexans. In this study, we searched for P. marinus methylerythritol phosphate (MEP) pathway genes, responsible for de novo isoprenoid synthesis in plastids, and determined the full-length gene sequences for 6 of 7 of these genes. Phylogenetic analyses revealed that each P. marinus gene clusters with orthologs from plastid-bearing eukaryotes, which have MEP pathway genes with essentially the same mosaic pattern of evolutionary origin. A new analytical method called sliding-window iteration of TargetP was developed to examine the distribution of targeting preferences. This analysis revealed that the sequenced genes encode bipartite targeting peptides that are characteristic of proteins targeted to secondary plastids originating from endosymbiosis of eukaryotic algae. These results support our idea that Perkinsus is a cryptic algal group containing nonphotosynthetic secondary plastids. In fact, immunofluorescent microscopy indicated that 1 of the MEP pathway enzymes, 1-deoxy-D-xylulose 5-phosphate reductoisomerase, was localized to small compartments near mitochondrion, which are possibly plastids. This tiny organelle seems to contain very low quantities of DNA or may even lack DNA entirely. The MEP pathway genes are a useful tool for investigating plastid evolution in both of the photosynthetic and nonphotosynthetic eukaryotes and led us to propose the hypothesis that ancestral "chromalveolates" harbored plastids before a secondary endosymbiotic event

  14. Fast detection of a protozoan pathogen, Perkinsus marinus, using AlGaN/GaN high electron mobility transistors

    NASA Astrophysics Data System (ADS)

    Wang, Yu-Lin; Chu, B. H.; Chen, K. H.; Chang, C. Y.; Lele, T. P.; Papadi, G.; Coleman, J. K.; Sheppard, B. J.; Dungen, C. F.; Pearton, S. J.; Johnson, J. W.; Rajagopal, P.; Roberts, J. C.; Piner, E. L.; Linthicum, K. J.; Ren, F.

    2009-06-01

    Antibody-functionalized, Au-gated AlGaN/GaN high electron mobility transistors (HEMTs) were used to detect Perkinsus marinus. The antibody was anchored to the gate area through immobilized thioglycolic acid. The AlGaN/GaN HEMT drain-source current showed a rapid response of less than 5 s when the infected solution was added to the antibody-immobilized surface. The sensor can be recycled with a phosphate buffered saline wash. These results clearly demonstrate the promise of field-deployable electronic biological sensors based on AlGaN/GaN HEMTs for Perkinsus marinus detection.

  15. Role of physical barriers in the control of sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Hunn, J.B.; Youngs, W.D.

    1980-01-01

    Mechanical and electromechanical barriers played a significant role in the initial attempts to control sea lamprey (Petromyzon marinus) populations in the upper Great Lakes. More recently electromechanical weirs have been used to assess the relative abundance of spawning-run sea lampreys in Lake Superior. Development of an integrated control approach to sea lamprey control has stimulated an ongoing research program to define structural and/or velocity criteria that can be used to design barrier dams that block spawning runs of sea lamprey

  16. Endocrine events associated with spawning behavior in the sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Linville, Jane E.; Hanson, Lee H.; Sower, Stacia A.

    1987-01-01

    Levels of estradiol, progesterone, and testosterone were determined in plasma of sea lamprey (Petromyzon marinus) undergoing certain behaviors associated with spawning in natural and artifical stream environments. Significantly higher levels of estradiol, progesterone, and testosterone were found in males than in females. In the artifical spawning channel, levels of estradiol were significantly higher in females exhibiting resting and swimming behaviors than in fanning, nest building, and spawning behaviors. No significant correlation was found with either progesterone or testosterone levels and the various reproductive behaviors. The data presented are the first experimental evidence that suggest gonadal steroids may be correlated with certain reproductive behaviors in the sea lamprey.

  17. The Effects of the Toxic Cyanobacterium Limnothrix (Strain AC0243) on Bufo marinus Larvae

    PubMed Central

    Daniels, Olivia; Fabbro, Larelle; Makiela, Sandrine

    2014-01-01

    Limnothrix (strain AC0243) is a cyanobacterium, which has only recently been identified as toxin producing. Under laboratory conditions, Bufo marinus larvae were exposed to 100,000 cells mL−1 of Limnothrix (strain AC0243) live cultures for seven days. Histological examinations were conducted post mortem and revealed damage to the notochord, eyes, brain, liver, kidney, pancreas, gastrointestinal tract, and heart. The histopathological results highlight the toxicological impact of this strain, particularly during developmental stages. Toxicological similarities to β-N-Methylamino-l-alanine are discussed. PMID:24662524

  18. Heterokont Predator Develorapax marinus gen. et sp. nov. – A Model of the Ochrophyte Ancestor

    PubMed Central

    Aleoshin, Vladimir V.; Mylnikov, Alexander P.; Mirzaeva, Gulnara S.; Mikhailov, Kirill V.; Karpov, Sergey A.

    2016-01-01

    Heterotrophic lineages of Heterokonta (or stramenopiles), in contrast to a single monophyletic group of autotrophs, Ochrophyta, form several clades that independently branch off the heterokont stem lineage. The nearest neighbors of Ochrophyta in the phylogenetic tree appear to be almost exclusively bacterivorous, whereas the hypothesis of plastid acquisition by the ancestors of the ochrophyte lineage suggests an ability to engulf eukaryotic alga. In line with this hypothesis, the heterotrophic predator at the base of the ochrophyte lineage may be regarded as a model for the ochrophyte ancestor. Here, we present a new genus and species of marine free-living heterotrophic heterokont Develorapax marinus, which falls into an isolated heterokont cluster, along with the marine flagellate Developayella elegans, and is able to engulf eukaryotic cells. Together with environmental sequences D. marinus and D. elegans form a class-level clade Developea nom. nov. represented by species adapted to different environmental conditions and with a wide geographical distribution. The position of Developea among Heterokonta in large-scale phylogenetic tree is discussed. We propose that members of the Developea clade represent a model for transition from bacterivory to a predatory feeding mode by selection for larger prey. Presumably, such transition in the grazing strategy is possible in the presence of bacterial biofilms or aggregates expected in eutrophic environment, and has likely occurred in the ochrophyte ancestor. PMID:27536283

  19. Heterokont Predator Develorapax marinus gen. et sp. nov. - A Model of the Ochrophyte Ancestor.

    PubMed

    Aleoshin, Vladimir V; Mylnikov, Alexander P; Mirzaeva, Gulnara S; Mikhailov, Kirill V; Karpov, Sergey A

    2016-01-01

    Heterotrophic lineages of Heterokonta (or stramenopiles), in contrast to a single monophyletic group of autotrophs, Ochrophyta, form several clades that independently branch off the heterokont stem lineage. The nearest neighbors of Ochrophyta in the phylogenetic tree appear to be almost exclusively bacterivorous, whereas the hypothesis of plastid acquisition by the ancestors of the ochrophyte lineage suggests an ability to engulf eukaryotic alga. In line with this hypothesis, the heterotrophic predator at the base of the ochrophyte lineage may be regarded as a model for the ochrophyte ancestor. Here, we present a new genus and species of marine free-living heterotrophic heterokont Develorapax marinus, which falls into an isolated heterokont cluster, along with the marine flagellate Developayella elegans, and is able to engulf eukaryotic cells. Together with environmental sequences D. marinus and D. elegans form a class-level clade Developea nom. nov. represented by species adapted to different environmental conditions and with a wide geographical distribution. The position of Developea among Heterokonta in large-scale phylogenetic tree is discussed. We propose that members of the Developea clade represent a model for transition from bacterivory to a predatory feeding mode by selection for larger prey. Presumably, such transition in the grazing strategy is possible in the presence of bacterial biofilms or aggregates expected in eutrophic environment, and has likely occurred in the ochrophyte ancestor. PMID:27536283

  20. Plasma steroid concentrations change in response to sexual behavior in Bufo marinus.

    PubMed

    Orchinik, M; Licht, P; Crews, D

    1988-09-01

    Steroid hormone concentrations change in response to social or environmental stimuli in many vertebrates. To test this phenomenon in an amphibian, we examined plasma androgen (A) and corticosterone (B) concentrations in male marine toads (Bufo marinus), a tropical species exhibiting intermale competition, amplectic clasping of females, and bouts of breeding behavior following rains. When males clasped females for 0, 1, 2, or 3 hr, plasma A concentrations were significantly and positively correlated with hours spent in amplexus. In field-sampled males, plasma A concentrations were higher in amplexing males than in single males. Among single males those found closer to breeding ponds had higher A concentrations than those more distant. These data support the hypothesis that sexual stimuli enhance plasma A concentrations in this amphibian. In 3-hr experimental tests and field-sampled males, B concentrations were higher in amplexing than in single males. Unlike some amphibians, short-term elevations of B apparently are not associated with decreased reproductive function. However, as in other amphibians in which high B concentrations are associated with stress-induced inhibition of reproduction, after 48-72 hr in captivity male toads showed high B concentrations and low plasma androgen concentrations. The bursts of sexual activities exhibited by B. marinus following heavy rains were associated with no changes in A concentration and with increased B concentration. PMID:3139541

  1. Genome Sequence of Radiation-Resistant Modestobacter marinus Strain BC501, a Representative Actinobacterium That Thrives on Calcareous Stone Surfaces

    PubMed Central

    Normand, Philippe; Gury, Jérôme; Pujic, Petar; Chouaia, Bessem; Crotti, Elena; Brusetti, Lorenzo; Daffonchio, Daniele; Vacherie, Benoit; Barbe, Valérie; Médigue, Claudine; Calteau, Alexandra; Ghodhbane-Gtari, Faten; Essoussi, Imen; Nouioui, Imen; Abbassi-Ghozzi, Ines

    2012-01-01

    Here we report the full genome sequence of Modestobacter marinus strain BC501, an actinobacterial isolate that thrives on stone surfaces. The generated chromosome is circular, with a length of 5.57 Mb and a G+C content of 74.13%, containing 5,445 protein-coding genes, 48 tRNAs, and 3 ribosomal operons. PMID:22887672

  2. PROGRESSION OF DISEASES CAUSED BY THE OYSTER PARASITES, PERKINSUS MARINUS AND HAPLOSPORIDIUM NELSONI, IN CRASSOSTREA VIRGINICA ON CONSTRUCTED INTERTIDAL REEFS

    EPA Science Inventory

    The progression of diseases caused by the oyster parasites, Perkinsus marinus and Haplosporidium nelsoni, were evaluated by periodic sampling (May 1994-Dec. 1995) of oysters, Crassostrea virginica, that set on an artificial reef located in the Piankatank River, Virginia, in Augus...

  3. Effects of salinity and temperature on in vitro cell cycle and proliferation of Perkinsus marinus from Brazil.

    PubMed

    Queiroga, Fernando Ramos; Marques-Santos, Luis Fernando; De Medeiros, Isac Almeida; Da Silva, Patrícia Mirella

    2016-04-01

    Field and in vitro studies have shown that high salinities and temperatures promote the proliferation and dissemination of Perkinsus marinus in several environments. In Brazil, the parasite infects native oysters Crassostrea gasar and Crassostrea rhizophorae in the Northeast (NE), where the temperature is high throughout the year. Despite the high prevalence of Perkinsus spp. infection in oysters from the NE of Brazil, no mortality events were reported by oyster farmers to date. The present study evaluated the effects of salinity (5, 20 and 35 psu) and temperature (15, 25 and 35 °C) on in vitro proliferation of P. marinus isolated from a host (C. rhizophorae) in Brazil, for a period of up to 15 days and after the return to the control conditions (22 days; recovery). Different cellular parameters (changes of cell phase's composition, cell density, viability and production of reactive oxygen species) were analysed using flow cytometry. The results indicate that the P. marinus isolate was sensitive to the extreme salinities and temperatures analysed. Only the highest temperature caused lasting cell damage under prolonged exposure, impairing P. marinus recovery, which is likely to be associated with oxidative stress. These findings will contribute to the understanding of the dynamics of perkinsiosis in tropical regions. PMID:26888407

  4. Differential expression of serine protease inhibitors 1 and 2 in Crassostrea corteziensis and C. virginica infected with Perkinsus marinus.

    PubMed

    Gutiérrez-Rivera, J N; Arcos-Ortega, G F; Luna-González, A; Rodríguez-Jaramillo, M C; Arechiga-Carvajal, E T; Vázquez-Juárez, R

    2015-01-15

    Proliferation of Perkinsus marinus (Dermo) in vitro is inhibited by the action of 2 serine protease inhibitors belonging to the I-84 family. We compared the levels of expression of serine protease inhibitors 1 and 2 (SPI-1 and SPI-2) in 2 oyster species (Crassostrea virginica and C. corteziensis) inoculated with the parasite P. marinus. C. virginica is well known to be susceptible to this parasite, whereas C. corteziensis is apparently more tolerant. Oysters were inoculated with trophozoites (1 × 106 trophozoites oyster-1) of P. marinus while control oysters were injected with saline solution. Oysters were maintained in a closed water system for 2 wk. The oysters were then sacrificed and parasite burden, histological damage, and gene expression were evaluated. The results showed that the challenged oysters presented a significant increase in parasite burden, which generated histological damage in digestive gland and gills. Quantitative PCR detected significant differences in SPI-1 and SPI-2 expression levels in the 2 oyster species, with C. corteziensis showing higher expression levels than C. virginica as a response to P. marinus inoculation. Our results provide valuable information for the understanding of the defense response in C. corteziensis and a possible explanation for its tolerance to the parasite. PMID:25590769

  5. Mutation in promoter region of a serine protease inhibitor confers Perkinsus marinus resistance in the eastern oyster (Crassostrea virginica).

    PubMed

    He, Yan; Yu, Haiyang; Bao, Zhenmin; Zhang, Quanqi; Guo, Ximing

    2012-08-01

    Protease inhibitors from the host may inhibit proteases from invading pathogens and confer resistance. We have previously shown that a single-nucleotide polymorphism (SNP198C) in a serine protease inhibitor gene (cvSI-1) is associated with Perkinsus marinus resistance in the eastern oyster. As SNP198 is synonymous, we studied whether its linkage to polymorphism at the promoter region could explain the resistance. A 631 bp fragment of the promoter region was cloned by genome-walking and resequenced, revealing 22 SNPs and 3 insertion/deletions (indels). A 25 bp indel at position -404 was genotyped along with SNP198 for association analysis using before- and after-mortality samples. After mortalities that were primarily caused by P. marinus, the frequency of deletion allele at -404indel increased by 15.6% (p = 0.0437), while that of SNP198C increased by only 3.4% (p = 0.5756). The resistance alleles at the two loci were coupled in 79.6% of the oysters. Oysters with the deletion allele at -404indel showed significant (p = 0.0189) up-regulation of cvSI-1 expression under P. marinus challenge. Our results suggest that mutation at the promoter region causes increased transcription of cvSI-1, which in turn confers P. marinus resistance in the eastern oyster likely through inhibiting pathogenic proteases from the parasite. PMID:22683517

  6. Protease inhibitors and haemagglutinins associated with resistance to the protozoan parasite, Perkinsus marinus, in the Pacific oyster, Crassostrea gigas.

    PubMed

    Romestand, B; Corbier, F; Roch, P

    2002-10-01

    Perkinsus marinus is a protozoan responsible for dramatic mortality in the Eastern oyster, Crassostrea virginica, but not in the Pacific oyster, C. gigas. To understand the host-parasite relationship, we inoculated P. marinus trophozoites into the shell cavity of C. gigas and measured, over 2 months, (i) intensity of infection, (ii) protease inhibitory activities against P. marinus proteases and against bovine z-chymotrypsin, (iii) plasma haemagglutinin titre, (iv) plasma protein concentration, (v) plasma lysozyme activity and (vi) total haemocyte count. We observed that the highest protease inhibitory activities and haemagglutinin titres (3-10 days post-challenge) preceded parasite elimination (initiated 7 days post-challenge). In contrast, plasma protein concentration, lysozyme activity and total haemocyte count showed no significant modification following the challenge. It is hypothesized that the capacity of C. gigas to increase its protease inhibitors represents the key event in resistance to parasite infection by neutralizing the proteases secreted by P. marinus, thus preserving the oyster haemagglutinins from degradation. Such haemagglutinins will be ready to act as opsonins stimulating phagocytosis of parasites. PMID:12403320

  7. Quantitative assessment of the proliferation of the protozoan parasite Perkinsus marinus using a bioluminescence assay for ATP content.

    PubMed

    Shridhar, Surekha; Hassan, Kolaleh; Sullivan, David J; Vasta, Gerardo R; Fernández Robledo, José A

    2013-12-01

    Perkinsus marinus is a protozoan parasite that causes "Dermo" disease in the eastern oyster Crasssostrea virginica in coastal areas of the USA. Until now, intervention strategies against the parasite have found limited success, and Dermo still remains one of the main hurdles for the restoration of oyster populations. We adapted a commercial adenosine tri-phosphate (ATP) content-based assay to assess the in vitro proliferation of P. marinus in a 96-well plate format, and validated the method by measuring the effects of potential anti-proliferative compounds. The sensitivity (1.5-3.1 × 10(4) cells/well), linearity (R (2) = 0.983), and signal stability (60 min) support the reliability of the assay for assessing cell proliferation. Validation of the assay by culturing P. marinus in the presence of increasing concentrations of triclosan showed a dose-response profile. The IC50 value obtained was higher than that reported earlier, possibly due to the use of different viability assay methods and a different P. marinus strain. The antibiotics G418 and tetracycline and the herbicide fluridone were active against P. marinus proliferation; the IC50 of chloramphenicol, ciprofloxacin, and atrazine was relatively high suggesting either off-target effects or inability to reach the targets. The validation of the ATP-based assay, together with significant advantages of the Perkinsus culture methodology (homogeneity, reproducibility, and high cell densities), underscores the value of this assay for developing high-throughput screens for the identification of novel leader compounds against Perkinsus species, and most importantly, for the closely-related apicomplexan parasites. PMID:24533297

  8. Viability, infectivity and fatty acid synthetic activity of Perkinsus marinus meront cells incubated in estuarine and artificial seawater.

    PubMed

    Chu, Fu-Lin E; Lund, Eric D

    2006-07-25

    We investigated the viability and fatty acid synthetic activity of in vitro cultured Perkinsus marinus (Dermo) in lipid-free medium and estuarine water, and the infectivity of P. marinus maintained in artificial seawater (ASW). Viability and fatty acid synthetic activity in 7 d old P. marinus meronts maintained in lipid-free medium and estuarine water were tested. The infectivity of meronts incubated in ASW was examined by first incubating P. marinus meronts in ASW for 2, 3 or 7 d, and then inoculating viable ASW-incubated meronts into the shell cavity of individual oysters Crassostrea virginica. P. marinus infection prevalence and intensity in oysters were determined 9 wk post-inoculation. Heavy mortality occurred in meronts maintained in estuarine water, a drop from an initial value of 100% viable to 7.8 and 6.1% after 3 and 14 d incubation, respectively. Viability was 85 and 67% in meronts maintained in lipid-free medium for 3 and 24 d, respectively. Meronts kept in lipid-free medium for 14 d retained their ability to synthesize fatty acids. Viable meronts incubated in ASW remained infective for up to 7 d. The infection prevalences were 85, 48 and 100%, in the treatments inoculated with viable meronts that were incubated in ASW for 2, 3 and 7 d, respectively. Infection prevalence in the group inoculated with viable meronts immediately after they were transferred to ASW ranged from 61 to 85%. Our results suggest that in nature meronts can survive for at least 14 d outside the host. Viable meronts are not only infective, but are also able to replicate and retain their fatty acid synthetic ability for 7 d. PMID:16956060

  9. Perkinsus marinus tissue distribution and seasonal variation in oysters Crassostrea virginica from Florida, Virginia and New York.

    PubMed

    Oliver, L M; Fisher, W S; Ford, S E; Calvo, L M; Burreson, E M; Sutton, E B; Gandy, J

    1998-09-11

    Perkinsus marinus infection intensity was measured in eastern oysters Crassostrea virginica collected in October and December 1993, and March, May, and July 1994 from 3 U.S. sites: Apalachicola Bay (FL), Chesapeake Bay (VA), and Oyster Bay (NY). Gill, mantle, digestive gland, adductor muscle, hemolymph, and remaining tissue (including gonadal material and rectum) were dissected from 20 oysters from each site at each collection time. Samples were separately diagnosed for P. marinus infections by incubation in Ray's Fluid Thioglycollate Medium (RFTM) and subsequent microscopic quantification of purified enlarged hypnospores. At all sampling times and sites, average P. marinus infection intensity (g wet wt tissue-1 or ml hemolymph-1) was lowest in hemolymph samples, and generally highest in the digestive gland. Perkinsus marinus prevalence was 100% at both FL and NY sites for each of the 5 collection times, and, for the VA site, was less than 100% in only 1 month (May 1994). Seasonal intensity patterns and mean total body burdens differed among the sites. Average body burden was highest in VA during October and progressively declined to a minimum in May. This decline was probably due to mortality of heavily infected oysters and diminution of parasite activity associated with colder temperatures and reduced salinities. Intensities varied little during the months of October and December at both the FL and NY sites. Minimum average intensities were observed in March in FL oysters and May in NY oysters. Relatively high P. marinus infection levels that persisted throughout the winter in NY oysters compared with VA oysters could reflect constant high salinity in Long Island Sound which favors parasite activity, and also rapid decline in temperature in the fall that may have prevented epizootic oyster mortalities. PMID:9789979

  10. Quantitative assessment of the proliferation of the protozoan parasite Perkinsus marinus using a bioluminescence assay for ATP content

    PubMed Central

    Shridhar, Surekha; Hassan, Kolaleh; Sullivan, David J.; Vasta, Gerardo R.; Fernández Robledo, José A.

    2013-01-01

    Perkinsus marinus is a protozoan parasite that causes “Dermo” disease in the eastern oyster Crasssostrea virginica in coastal areas of the USA. Until now, intervention strategies against the parasite have found limited success, and Dermo still remains one of the main hurdles for the restoration of oyster populations. We adapted a commercial adenosine tri-phosphate (ATP) content-based assay to assess the in vitro proliferation of P. marinus in a 96-well plate format, and validated the method by measuring the effects of potential anti-proliferative compounds. The sensitivity (1.5–3.1 × 104 cells/well), linearity (R2 = 0.983), and signal stability (60 min) support the reliability of the assay for assessing cell proliferation. Validation of the assay by culturing P. marinus in the presence of increasing concentrations of triclosan showed a dose–response profile. The IC50 value obtained was higher than that reported earlier, possibly due to the use of different viability assay methods and a different P. marinus strain. The antibiotics G418 and tetracycline and the herbicide fluridone were active against P. marinus proliferation; the IC50 of chloramphenicol, ciprofloxacin, and atrazine was relatively high suggesting either off-target effects or inability to reach the targets. The validation of the ATP-based assay, together with significant advantages of the Perkinsus culture methodology (homogeneity, reproducibility, and high cell densities), underscores the value of this assay for developing high-throughput screens for the identification of novel leader compounds against Perkinsus species, and most importantly, for the closely-related apicomplexan parasites. PMID:24533297

  11. INFECTION INTENSITY OF PERKINSUS MARINUS DISEASE IN CRASSOSTREA VIRGINICA (GMELIN, 1791) FROM THE GULF OF MEXICO MAINTAINED UNDER DIFFERENT LABORATORY CONDITIONS

    EPA Science Inventory

    A protozoan parasite, Perkinsus marinus, has been responsible for infection and mortality of eastern oysters, Crassostrea virginica, since before 1950. tudies on the course of infection intensity (incidence) in individual animals have been restricted by the need to sacrifice anim...

  12. Sequencing of the sea lamprey (Petromyzon marinus) genome provides insights into vertebrate evolution.

    PubMed

    Smith, Jeramiah J; Kuraku, Shigehiro; Holt, Carson; Sauka-Spengler, Tatjana; Jiang, Ning; Campbell, Michael S; Yandell, Mark D; Manousaki, Tereza; Meyer, Axel; Bloom, Ona E; Morgan, Jennifer R; Buxbaum, Joseph D; Sachidanandam, Ravi; Sims, Carrie; Garruss, Alexander S; Cook, Malcolm; Krumlauf, Robb; Wiedemann, Leanne M; Sower, Stacia A; Decatur, Wayne A; Hall, Jeffrey A; Amemiya, Chris T; Saha, Nil R; Buckley, Katherine M; Rast, Jonathan P; Das, Sabyasachi; Hirano, Masayuki; McCurley, Nathanael; Guo, Peng; Rohner, Nicolas; Tabin, Clifford J; Piccinelli, Paul; Elgar, Greg; Ruffier, Magali; Aken, Bronwen L; Searle, Stephen M J; Muffato, Matthieu; Pignatelli, Miguel; Herrero, Javier; Jones, Matthew; Brown, C Titus; Chung-Davidson, Yu-Wen; Nanlohy, Kaben G; Libants, Scot V; Yeh, Chu-Yin; McCauley, David W; Langeland, James A; Pancer, Zeev; Fritzsch, Bernd; de Jong, Pieter J; Zhu, Baoli; Fulton, Lucinda L; Theising, Brenda; Flicek, Paul; Bronner, Marianne E; Warren, Wesley C; Clifton, Sandra W; Wilson, Richard K; Li, Weiming

    2013-04-01

    Lampreys are representatives of an ancient vertebrate lineage that diverged from our own ∼500 million years ago. By virtue of this deeply shared ancestry, the sea lamprey (P. marinus) genome is uniquely poised to provide insight into the ancestry of vertebrate genomes and the underlying principles of vertebrate biology. Here, we present the first lamprey whole-genome sequence and assembly. We note challenges faced owing to its high content of repetitive elements and GC bases, as well as the absence of broad-scale sequence information from closely related species. Analyses of the assembly indicate that two whole-genome duplications likely occurred before the divergence of ancestral lamprey and gnathostome lineages. Moreover, the results help define key evolutionary events within vertebrate lineages, including the origin of myelin-associated proteins and the development of appendages. The lamprey genome provides an important resource for reconstructing vertebrate origins and the evolutionary events that have shaped the genomes of extant organisms. PMID:23435085

  13. Ionophoretically applied acetylcholine and vagal stimulation in the arrested sinus venosus of the toad, Bufo marinus.

    PubMed Central

    Bramich, N J; Brock, J A; Edwards, F R; Hirst, G D

    1994-01-01

    1. The effects of acetylcholine (ACh), applied by ionophoresis, on the isolated arrested sinus venosus of the toad, Bufo marinus, were examined. 2. At each position where ACh was applied across the surface of sinus venosus preparations, a hyperpolarization was produced. These responses were abolished by hyoscine, indicating that muscarinic cholinoceptors are widely distributed over the surface of these muscle cells. 3. Vagal stimulation produced hyperpolarizations which were mimicked, to some extent, by ionophoretically applied ACh. 4. The responses to ionophoretically applied ACh were abolished by adding barium ions to the perfusion fluid, whereas responses to vagal stimulation persisted. 5. The responses to ionophoretically applied ACh were consistently slower than those to vagal stimulation. It is argued that the pathways activated by neural and applied ACh have different kinetics of activation. PMID:7965847

  14. Elimination of super(14)C-bisazir residues in adult sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Allen, J.L.; Dawson, V.K.

    1987-01-01

    Bisazir (P.P-bis(1-aziridinyl)-N-methylphosphinothioic amide), a chemosterilant, was administered to sea lampreys (Petromyzon marinus ) by intraperitoneal injection of 100 mg/kg or by immersion for 2 h in a 100- mg/L aqueous solution of the chemical. Whole body analysis of the injected lampreys showed that total residue concentrations decreased to 4.65 in males and 10.07 in females during the first day after injection, and to 1.46 in males and 3.74 in females after 10 days of withdrawal. Lampreys exposed by bath immersion contained residues of about 25 mu g/g of tissue immediately after exposure. The concentration ( mu g/g) decreased to 1.02 in males and 2.11 in females after 1 day of withdrawal and to 0.51 in males and 0.85 in females after 10 days.

  15. Sequencing of the sea lamprey (Petromyzon marinus) genome provides insights into vertebrate evolution

    PubMed Central

    Smith, Jeramiah J; Kuraku, Shigehiro; Holt, Carson; Sauka-Spengler, Tatjana; Jiang, Ning; Campbell, Michael S; Yandell, Mark D; Manousaki, Tereza; Meyer, Axel; Bloom, Ona E; Morgan, Jennifer R; Buxbaum, Joseph D; Sachidanandam, Ravi; Sims, Carrie; Garruss, Alexander S; Cook, Malcolm; Krumlauf, Robb; Wiedemann, Leanne M; Sower, Stacia A; Decatur, Wayne A; Hall, Jeffrey A; Amemiya, Chris T; Saha, Nil R; Buckley, Katherine M; Rast, Jonathan P; Das, Sabyasachi; Hirano, Masayuki; McCurley, Nathanael; Guo, Peng; Rohner, Nicolas; Tabin, Clifford J; Piccinelli, Paul; Elgar, Greg; Ruffier, Magali; Aken, Bronwen L; Searle, Stephen MJ; Muffato, Matthieu; Pignatelli, Miguel; Herrero, Javier; Jones, Matthew; Brown, C Titus; Chung-Davidson, Yu-Wen; Nanlohy, Kaben G; Libants, Scot V; Yeh, Chu-Yin; McCauley, David W; Langeland, James A; Pancer, Zeev; Fritzsch, Bernd; de Jong, Pieter J; Zhu, Baoli; Fulton, Lucinda L; Theising, Brenda; Flicek, Paul; Bronner, Marianne E; Warren, Wesley C; Clifton, Sandra W; Wilson, Richard K; Li, Weiming

    2013-01-01

    Lampreys are representatives of an ancient vertebrate lineage that diverged from our own ~500 million years ago. By virtue of this deeply shared ancestry, the sea lamprey (P. marinus) genome is uniquely poised to provide insight into the ancestry of vertebrate genomes and the underlying principles of vertebrate biology. Here, we present the first lamprey whole-genome sequence and assembly. We note challenges faced owing to its high content of repetitive elements and GC bases, as well as the absence of broad-scale sequence information from closely related species. Analyses of the assembly indicate that two whole-genome duplications likely occurred before the divergence of ancestral lamprey and gnathostome lineages. Moreover, the results help define key evolutionary events within vertebrate lineages, including the origin of myelin-associated proteins and the development of appendages. The lamprey genome provides an important resource for reconstructing vertebrate origins and the evolutionary events that have shaped the genomes of extant organisms. PMID:23435085

  16. Classification of lentic habitat for sea lamprey (Petromyzon marinus) larvae using a remote seabed classification device

    USGS Publications Warehouse

    Fodale, Michael F.; Bronte, Charles R.; Bergstedt, Roger A.; Cuddy, Douglas W.; Adams, Jean V.

    2003-01-01

    Lentic populations of larval sea lampreys (Petromyzon marinus) are suspected of being a major source of recruitment to parasitic stocks in some areas of the Great Lakes, and methods are needed to estimate habitat and population sizes. A deepwater electroshocker has been used to quantitatively assess larval sea lamprey populations in deepwater areas, however a method has not been developed to efficiently identify the most promising locations to sample in this environment. A remote seabed classification device (RoxAnn™) was used to identify soft substrates in a lentic area where sea lamprey larvae have been found in Batchawana Bay (Ontario) in eastern Lake Superior, and related those substrate types to larval distribution and occurrence. Presence of larvae was significantly related to substrate type, distance from the stream mouth, and slope of the lake bottom. Remote seabed classification would be a useful tool in the Sea Lamprey Control Program to identify the most promising locations to conduct larval surveys in lentic areas.

  17. Blood cell lineage in the sea lamprey, Petromyzon marinus (Pisces: Petromyzontidae)

    USGS Publications Warehouse

    Piavis, George W.; Hiatt, James L.

    1971-01-01

    Blood cell types of the sea lamprey, Petromyzon marinus, are described and identified and the lineage of mature circulating cells in peripheral blood is traced to blast cells in the hematopoietic fat body. The fat body appears to be the phylogenetic precursor of bone marrow in higher forms, since blood cells originate and begin maturation in this tissue. Experimental animals were injected first with a hematopoietic stimulant and then (at an experimentally determined time) with pertussis vaccine to release proliferated blood cells into peripheral blood. Peripheral blood for smears was collected by cardiac exsanguination; hematopoietic tissue was extirpated for imprints; and leucocyte preparations were made by a special technique. Blood cells of the sea lamprey are apparently products of at least four distinct blast cells, each of which has a 'one end' maturation process. Results of this investigation support the polyphyletic theory of blood cell formation.

  18. First record of Renibacterium salmoninarum in the sea lamprey (Petromyzon marinus).

    PubMed

    Eissa, A E; Elsayed, E E; McDonald, R; Faisal, M

    2006-07-01

    Bacterial kidney disease (BKD), caused by Renibacterium salmoninarum, is a widespread problem with major implications for salmonid fish species. The mechanisms by which the bacterium has reached high levels of infection previously unrecorded in the Laurentian Great Lakes are presently unknown. Research involving reservoirs and mechanisms of R. salmoninarum transmission in fish is lacking because of the ecologic complexity of heterogeneous habitats and the lack of adequate funding. Herein, we report on the isolation of R. salmoninarum from the kidneys of the sea lamprey (Petromyzon marinus). The bacterium was cultured from kidneys of 16% and 4% of lampreys collected from two locations within the Lake Ontario watershed in 2003 and 2004, respectively. The identity of bacterial colonies was verified with the nested polymerase chain reaction and quantitative enzyme-linked immunosorbent assay. PMID:17092886

  19. Influence of decontamination on induction of arthritis in Lewis rats by cell wall fragments of Eubacterium aerofaciens. Arthropathic properties of indigenous anaerobic bacteria.

    PubMed Central

    Kool, J; Severijnen, A J; Klasen, I S; Gerrits-Boeye, M Y; Hazenberg, M P

    1992-01-01

    Although the cause (or causes) of rheumatoid arthritis is unknown, many workers have suggested that microorganisms play a part. The intestinal flora in particular has been related to the development of joint inflammation. It has been shown previously that cell wall fragments of several anaerobic Gram positive intestinal bacteria of human origin are arthritogenic after a single intraperitoneal injection in Lewis rats. The part played by indigenous microflora in this model has now been studied by decontaminating Lewis rats before the injection of Eubacterium aerofaciens cell wall fragments. The pattern and severity of arthritis appeared to be comparable in decontaminated and control rats. The second goal of this work was to isolate arthritogenic bacteria from the autochthonous intestinal flora of rats. Only a limited number of bacteria showing a resemblance to arthritogenic strains from human intestinal flora (i.e. E aerofaciens and Bifidobacterium adolescentis) could be isolated. These strains did not induce chronic arthritis after intraperitoneal injection. This may explain why spontaneous arthritis did not develop in Lewis rats. Images PMID:1586251

  20. Flow cytometric analysis of lectin binding to in vitro-cultured Perkinsus marinus surface carbohydrates

    USGS Publications Warehouse

    Gauthier, J.D.; Jenkins, J.A.; La Peyre, Jerome F.

    2004-01-01

    Parasite surface glycoconjugates are frequently involved in cellular recognition and colonization of the host. This study reports on the identification of Perkinsus marinus surface carbohydrates by flow cytometric analyses of fluorescein isothiocyanate-conjugated lectin binding. Lectin-binding specificity was confirmed by sugar inhibition and Kolmogorov-Smirnov statistics. Clear, measurable fluorescence peaks were discriminated, and no parasite autofluorescence was observed. Parasites (GTLA-5 and Perkinsus-1 strains) harvested during log and stationary phases of growth in a protein-free medium reacted strongly with concanavalin A and wheat germ agglutinin, which bind to glucose-mannose and N-acetyl-D-glucosamine (GlcNAc) moieties, respectively. Both P. marinus strains bound with lower intensity to Maclura pomifera agglutinin, Bauhinia purpurea agglutinin, soybean agglutinin (N-acetyl-D-galactosamine-specific lectins), peanut agglutinin (PNA) (terminal galactose specific), and Griffonia simplicifolia II (GlcNAc specific). Only background fluorescence levels were detected with Ulex europaeus agglutinin I (L-fucose specific) and Limulus polyphemus agglutinin (sialic acid specific). The lectin-binding profiles were similar for the 2 strains except for a greater relative binding intensity of PNA for Perkinsus-1 and an overall greater lectin-binding capacity of Perkinsus-1 compared with GTLA-5. Growth stage comparisons revealed increased lectin-binding intensities during stationary phase compared with log phase of growth. This is the first report of the identification of surface glycoconjugates on a Perkinsus spp. by flow cytometry and the first to demonstrate that differential surface sugar expression is growth phase and strain dependent. ?? American Society of Parasitologists 2004.

  1. Neuropeptide Y family receptors Y1 and Y2 from sea lamprey, Petromyzon marinus.

    PubMed

    Xu, Bo; Lagman, David; Sundström, Görel; Larhammar, Dan

    2015-10-01

    The vertebrate gene family for neuropeptide Y (NPY) receptors expanded by duplication of the chromosome carrying the ancestral Y1-Y2-Y5 gene triplet. After loss of some duplicates, the ancestral jawed vertebrate had seven receptor subtypes forming the Y1 (including Y1, Y4, Y6, Y8), Y2 (including Y2, Y7) and Y5 (only Y5) subfamilies. Lampreys are considered to have experienced the same chromosome duplications as gnathostomes and should also be expected to have multiple receptor genes. However, previously only a Y4-like and a Y5 receptor have been cloned and characterized. Here we report the cloning and characterization of two additional receptors from the sea lamprey Petromyzon marinus. Sequence phylogeny alone could not with certainty assign their identity, but based on synteny comparisons of P. marinus and the Arctic lamprey, Lethenteron camtschaticum, with jawed vertebrates, the two receptors most likely are Y1 and Y2. Both receptors were expressed in human HEK293 cells and inositol phosphate assays were performed to determine the response to the three native lamprey peptides NPY, PYY and PMY. The three peptides have similar potencies in the nanomolar range for Y1. No obvious response to the three peptides was detected for Y2. Synteny analysis supports identification of the previously cloned receptor as Y4. No additional NPY receptor genes could be identified in the presently available lamprey genome assemblies. Thus, four NPY-family receptors have been identified in lampreys, orthologs of the same subtypes as in humans (Y1, Y2, Y4 and Y5), whereas many other vertebrate lineages have retained additional ancestral subtypes. PMID:26255155

  2. Flow cytometric analysis of lectin binding to in vitro-cultured Perkinsus marinus surface carbohydrates.

    PubMed

    Gauthier, Julie D; Jenkins, Jill A; La Peyre, Jerome F

    2004-06-01

    Parasite surface glycoconjugates are frequently involved in cellular recognition and colonization of the host. This study reports on the identification of Perkinsus marinus surface carbohydrates by flow cytometric analyses of fluorescein isothiocyanate-conjugated lectin binding. Lectin-binding specificity was confirmed by sugar inhibition and Kolmogorov-Smirnov statistics. Clear, measurable fluorescence peaks were discriminated, and no parasite autofluorescence was observed. Parasites (GTLA-5 and Perkinsus-1 strains) harvested during log and stationary phases of growth in a protein-free medium reacted strongly with concanavalin A and wheat germ agglutinin, which bind to glucose-mannose and N-acetyl-D-glucosamine (GlcNAc) moieties, respectively. Both P. marinus strains bound with lower intensity to Maclura pomifera agglutinin, Bauhinia purpurea agglutinin, soybean agglutinin (N-acetyl-D-galactosamine-specific lectins), peanut agglutinin (PNA) (terminal galactose specific), and Griffonia simplicifolia II (GlcNAc specific). Only background fluorescence levels were detected with Ulex europaeus agglutinin I (L-fucose specific) and Limulus polyphemus agglutinin (sialic acid specific). The lectin-binding profiles were similar for the 2 strains except for a greater relative binding intensity of PNA for Perkinsus-1 and an overall greater lectin-binding capacity of Perkinsus-1 compared with GTLA-5. Growth stage comparisons revealed increased lectin-binding intensities during stationary phase compared with log phase of growth. This is the first report of the identification of surface glycoconjugates on a Perkinsus spp. by flow cytometry and the first to demonstrate that differential surface sugar expression is growth phase and strain dependent. PMID:15270084

  3. Sterility method of pest control and its potential role in an integrated sea lamprey (Petromyzon marinus) control program

    USGS Publications Warehouse

    Hanson, Lee H.; Manion, Patrick J.

    1980-01-01

    The sterility method of pest control could be an effective tool in the sea lamprey (Petromyzon marinus) control program in the Great Lakes. Some of the requirements for its successful application have been met. A field study demonstrated that the release of male sea lampreys, sterilized by the injection of 100 mg/kg of P,P-bis(1-aziridinyl)-N-methylphosphinothioic amide (bisazir), will reduce the number of viable larvae produced. The actual reduction in reproductive success that occurred was directly related to the ratio of sterile to normal males in the population. The technique can be used in many ways in an integrated control program and has considerable potential for the more effective control of the sea lamprey. Eradication is a distinct possibility.Key words: sea lamprey, Petromyzon marinus; pest control, fish control, sterile-male technique, sterilization, chemosterilants, bisazir, Great Lakes

  4. A review of current state of knowledge concerning Perkinsus marinus effects on Crassostrea virginica (Gmelin) (the eastern oyster).

    PubMed

    Smolowitz, R

    2013-05-01

    The eastern oyster, Crassostrea virginica (Gmelin), is both an important component of our estuaries and an important farmed food animal along the east and south coasts of the United States. Its populations have been significantly diminished in the wild due to decades of overfishing beginning in the 1890 s. Unfortunately, in 1950, a new disease in eastern oysters caused by the protistan agent, Perkinsus marinus, was identified. The disease, resulting from infection with this protozoan, leads to high mortality of both wild and cultured eastern oysters. Current restoration efforts are hampered by the disease, as is the aquaculture of this economically important food. The parasite infects hemocytes and causes hemolytic anemia and general degeneration of the tissues, leading to death. Ongoing research efforts are attempting to develop oysters resistant to the disease. Transport regulations exist in may states. Infection with P. marinus is listed as a reportable disease by the World Health Organization. PMID:23462867

  5. Epizootiology of Perkinsus marinus, parasite of the pleasure oyster Crassostrea corteziensis, in the Pacific coast of Mexico.

    PubMed

    Cáceres-Martínez, Jorge; Madero-López, Luis Humberto; Padilla-Lardizábal, Gloria; Vásquez-Yeomans, Rebeca

    2016-09-01

    The protozoan parasite Perkinsus marinus is the etiological agent of "dermo disease". This pathogen is considered by the World Organization for Animal Health (OIE) as reportable due to the high mortalities that it produces in the eastern oyster Crassostrea virginica in the US. In 2006, this parasite was detected in the pleasure oyster Crassostrea corteziensis in Nayarit on the Pacific coast of Mexico, indicating a new host and an extension of its known distribution. Epizootiological data of P. marinus in the pleasure oyster are unknown. With the objective of determining the prevalence and intensity in relation with temperature and salinity throughout time, as well as for studying interactions of host size and sex with the parasite, a monthly sampling was carried out in two aquaculture sites of Nayarit from 2007 to 2014. A total of 7700 oysters were analyzed. In both localities, prevalence was low in winter (<6%) when temperature and salinity fluctuated around 24°C and 33, respectively; and the highest prevalence values occurred during summer (37%) when temperature and salinity were around 30°C and 20, respectively. Infection intensity increased in summer, but severe cases remained on average <10%. Larger oysters showed the highest prevalence and intensity, and higher prevalence were generally observed in females. No unusual mortalities directly related with P. marinus were observed. PMID:27403560

  6. Development of a PCR-ELISA assay for diagnosis of Perkinsus marinus and Perkinsus atlanticus infections in bivalve molluscs.

    PubMed

    Elandalloussi, Laurence M; Leite, Ricardo M; Afonso, Ricardo; Nunes, Patrícia A; Robledo, José A F; Vasta, Gerardo R; Cancela, M Leonor

    2004-04-01

    Perkinsus atlanticus and P. marinus have been associated with mass mortality of bivalve molluscs. Perkinsus infections are routinely diagnosed by histology or the fluid thioglycollate medium (FTM) assay. In this study, we describe the development of a PCR-enzyme-linked immunosorbent assay (ELISA) for amplification and rapid detection of Perkinsus species. The PCR reactions were selected to either amplify an IGS sequence region shared by currently accepted Perkinsus species or to simultaneously amplify IGS regions specific to either P. atlanticus or P. marinus. The specific hybridisation of DIG-labelled amplified products to species-specific capture probes was detected colorimetrically. This assay is able to specifically detect P. atlanticus and P. marinus, and the intensity of the colorimetric signal is dependent upon the amount of amplified product. The PCR-ELISA assay format is 100-fold more sensitive than visualisation of PCR products on ethidium bromide (EtdBr)-stained agarose gels, and as sensitive as Southern hybridisation. The sensitivity limit of PCR-ELISA was 1 pg of DNA from P. atlanticus. No cross-reactivity of the assay was observed against the host DNA. When applied to the detection of P. atlanticus in clams, 39 samples out of 45 yielded concordant results for FTM assay and PCR-ELISA detection. PMID:15051117

  7. Two Membrane-Associated NiFeS-Carbon Monoxide Dehydrogenases from the Anaerobic Carbon-Monoxide-Utilizing Eubacterium Carboxydothermus hydrogenoformans

    PubMed Central

    Svetlitchnyi, Vitali; Peschel, Christine; Acker, Georg; Meyer, Ortwin

    2001-01-01

    Two monofunctional NiFeS carbon monoxide (CO) dehydrogenases, designated CODH I and CODH II, were purified to homogeneity from the anaerobic CO-utilizing eubacterium Carboxydothermus hydrogenoformans. Both enzymes differ in their subunit molecular masses, N-terminal sequences, peptide maps, and immunological reactivities. Immunogold labeling of ultrathin sections revealed both CODHs in association with the inner aspect of the cytoplasmic membrane. Both enzymes catalyze the reaction CO + H2O → CO2 + 2 e− + 2 H+. Oxidized viologen dyes are effective electron acceptors. The specific enzyme activities were 15,756 (CODH I) and 13,828 (CODH II) μmol of CO oxidized min−1 mg−1 of protein (methyl viologen, pH 8.0, 70°C). The two enzymes oxidize CO very efficiently, as indicated by kcat/Km values at 70°C of 1.3 · 109 M−1 CO s−1 (CODH I) and 1.7 · 109 M−1 CO s−1 (CODH II). The apparent Km values at pH 8.0 and 70°C are 30 and 18 μM CO for CODH I and CODH II, respectively. Acetyl coenzyme A synthase activity is not associated with the enzymes. CODH I (125 kDa, 62.5-kDa subunit) and CODH II (129 kDa, 64.5-kDa subunit) are homodimers containing 1.3 to 1.4 and 1.7 atoms of Ni, 20 to 22 and 20 to 24 atoms of Fe, and 22 and 19 atoms of acid-labile sulfur, respectively. Electron paramagnetic resonance (EPR) spectroscopy revealed signals indicative of [4Fe-4S] clusters. Ni was EPR silent under any conditions tested. It is proposed that CODH I is involved in energy generation and that CODH II serves in anabolic functions. PMID:11489867

  8. Effects of polyamines from Thermus thermophilus, an extreme-thermophilic eubacterium, on tRNA methylation by tRNA (Gm18) methyltransferase (TrmH).

    PubMed

    Hori, Hiroyuki; Terui, Yusuke; Nakamoto, Chisato; Iwashita, Chikako; Ochi, Anna; Watanabe, Kazunori; Oshima, Tairo

    2016-05-01

    Thermus thermophilus is an extreme-thermophilic eubacterium, which grows at a wide range of temperatures (50-83°C). This thermophile produces various polyamines including long and branched polyamines. In tRNAs from T. thermophilus, three distinct modifications, 2'-O-methylguanosine at position 18 (Gm18), 5-methyl-2-thiouridine at position 54 and N(1)-methyladenosine at position 58, are assembled at the elbow region to stabilize the L-shaped tRNA structure. However, the structures of unmodified tRNA precursors are disrupted at high temperatures. We hypothesize that polyamine(s) might have a positive effect on the modification process of unmodified tRNA transcript. We investigated the effects of eight polyamines on Gm18 formation in the yeast tRNA(Phe) transcript by tRNA (Gm18) methyltransferase (TrmH). Higher concentrations of linear polyamines inhibited TrmH activity at 55°C, while optimum concentration increased TrmH activity at 45-75°C. Exceptionally, caldohexamine, a long polyamine, did not show any positive effect on the TrmH activity at 55°C. However, temperature-dependent experiments revealed that 1 mM caldohexamine increased TrmH activity at 60-80°C. Furthermore, 0.25 mM tetrakis(3-aminopropy)ammonium, a branched polyamine, increased TrmH activity at a broad range of temperatures (40-85°C). Thus, caldohexamine and tetrakis(3-aminopropy)ammonium were found to enhance the TrmH activity at high temperatures. PMID:26721905

  9. Purification and characterization of extremely thermostable beta-mannanase, beta-mannosidase, and alpha-galactosidase from the hyperthermophilic eubacterium Thermotoga neapolitana 5068.

    PubMed

    Duffaud, G D; McCutchen, C M; Leduc, P; Parker, K N; Kelly, R M

    1997-01-01

    Thermostable and thermoactive beta-mannanase (1,4-beta-D-mannan mannanohydrolase [EC 3.2.1.78]), beta-mannosidase (beta-D-mannopyranoside hydrolase [EC 3.2.1.25]) and alpha-galactosidase (alpha-D-galactoside galactohydrolase [EC 3.2.1.22]) were purified to homogeneity from cell extracts and extracellular culture supernatants of the hyperthermophilic eubacterium Thermotoga neapolitana 5068 grown on guar gum-based media. The beta-mannanase was an extracellular monomeric enzyme with a molecular mass of 65 kDa. The optimal temperature for activity was 90 to 92 degrees C, with half-lives (t1/2) of 34 h at 85 degrees C, 13 h at 90 degrees C, and 35 min at 100 degrees C. The beta-mannosidase and alpha-galactosidase were found primarily in cell extracts. The beta-mannosidase was a homodimer consisting of approximately 100-kDa molecular mass subunits. The optimal temperature for activity was 87 degrees C, with t1/2 of 18 h at 85 degrees C, 42 min at 90 degrees C, and 2 min at 98 degrees C. The alpha-galactosidase was a 61-kDa monomeric enzyme with a temperature optimum of 100 to 103 degrees C and t1/2 of 9 h at 85 degrees C, 2 h at 90 degrees C, and 3 min at 100 degrees C. These enzymes represent the most thermostable and thermoactive versions of these types yet reported and probably act synergistically to hydrolyze extracellular galactomannans to monosaccharides by T. neapolitana for nutritional purposes. The significance of such substrates in geothermal environments remains to be seen. PMID:8979350

  10. Energy Conservation Model Based on Genomic and Experimental Analyses of a Carbon Monoxide-Utilizing, Butyrate-Forming Acetogen, Eubacterium limosum KIST612

    PubMed Central

    Jeong, Jiyeong; Bertsch, Johannes; Hess, Verena; Choi, Sunju; Choi, In-Geol

    2015-01-01

    Eubacterium limosum KIST612 is one of the few acetogens that can produce butyrate from carbon monoxide. We have used a genome-guided analysis to delineate the path of butyrate formation, the enzymes involved, and the potential coupling to ATP synthesis. Oxidation of CO is catalyzed by the acetyl-coenzyme A (CoA) synthase/CO dehydrogenase and coupled to the reduction of ferredoxin. Oxidation of reduced ferredoxin is catalyzed by the Rnf complex and Na+ dependent. Consistent with the finding of a Na+-dependent Rnf complex is the presence of a conserved Na+-binding motif in the c subunit of the ATP synthase. Butyrate formation is from acetyl-CoA via acetoacetyl-CoA, hydroxybutyryl-CoA, crotonyl-CoA, and butyryl-CoA and is consistent with the finding of a gene cluster that encodes the enzymes for this pathway. The activity of the butyryl-CoA dehydrogenase was demonstrated. Reduction of crotonyl-CoA to butyryl-CoA with NADH as the reductant was coupled to reduction of ferredoxin. We postulate that the butyryl-CoA dehydrogenase uses flavin-based electron bifurcation to reduce ferredoxin, which is consistent with the finding of etfA and etfB genes next to it. The overall ATP yield was calculated and is significantly higher than the one obtained with H2 + CO2. The energetic benefit may be one reason that butyrate is formed only from CO but not from H2 + CO2. PMID:25956767

  11. Eubacterium limosum activates isoxanthohumol from hops (Humulus lupulus L.) into the potent phytoestrogen 8-prenylnaringenin in vitro and in rat intestine.

    PubMed

    Possemiers, Sam; Rabot, Sylvie; Espín, Juan Carlos; Bruneau, Aurélia; Philippe, Catherine; González-Sarrías, Antonio; Heyerick, Arne; Tomás-Barberán, Francisco A; De Keukeleire, Denis; Verstraete, Willy

    2008-07-01

    Recently, it was shown that the exposure to the potent hop phytoestrogen 8-prenylnaringenin (8-PN) depends on intestinal bacterial activation of isoxanthohumol (IX), but this occurs in only one-third of tested individuals. As the butyrate-producing Eubacterium limosum can produce 8-PN from IX, a probiotic strategy was applied to investigate whether 8-PN production could be increased in low 8-PN producers, thus balancing phytoestrogen exposure. Using fecal samples from high (Hop +) and low (Hop -) 8-PN-producing individuals, a Hop + and Hop - dynamic intestinal model was developed. In parallel, Hop + and Hop - human microbiota-associated rats were developed, germ-free (GF) rats acting as negative controls. IX and then IX + E. limosum were administered in the intestinal model and to the rats, and changes in 8-PN production and exposure were assessed. After dosing IX, 80% was converted into 8-PN in the Hop + model and highest 8-PN production, plasma concentrations, and urinary and fecal excretion occurred in the Hop + rats. Administration of the bacterium triggered 8-PN production in the GF rats and increased 8-PN production in the Hop - model and Hop - rats. 8-PN excretion was similar in the feces (294.1 +/- 132.2 nmol/d) and urine (8.5 +/- 1.1 nmol/d ) of all rats (n = 18). In addition, butyrate production increased in all rats. In conclusion, intestinal microbiota determined 8-PN production and exposure after IX intake. Moreover, E. limosum administration increased 8-PN production in low producers, resulting in similar 8-PN production in all rats. PMID:18567753

  12. Humanized HLA-DR4 Mice Fed with the Protozoan Pathogen of Oysters Perkinsus Marinus (Dermo) Do Not Develop Noticeable Pathology but Elicit Systemic Immunity

    PubMed Central

    Kleschenko, Yuliya; Pow-Sang, Luis; Brumeanu, Teodor D.; Villasante, Eileen Franke; Vasta, Gerardo R.; Fernández-Robledo, José-Antonio; Casares, Sofia

    2014-01-01

    Perkinsus marinus (Phylum Perkinsozoa) is a marine protozoan parasite responsible for “Dermo” disease in oysters, which has caused extensive damage to the shellfish industry and estuarine environment. The infection prevalence has been estimated in some areas to be as high as 100%, often causing death of infected oysters within 1–2 years post-infection. Human consumption of the parasites via infected oysters is thus likely to occur, but to our knowledge the effect of oral consumption of P. marinus has not been investigated in humans or other mammals. To address the question we used humanized mice expressing HLA-DR4 molecules and lacking expression of mouse MHC-class II molecules (DR4.EA0) in such a way that CD4 T cell responses are solely restricted by the human HLA-DR4 molecule. The DR4.EA0 mice did not develop diarrhea or any detectable pathology in the gastrointestinal tract or lungs following single or repeated feedings with live P. marinus parasites. Furthermore, lymphocyte populations in the gut associated lymphoid tissue and spleen were unaltered in the parasite-fed mice ruling out local or systemic inflammation. Notably, naïve DR4.EA0 mice had antibodies (IgM and IgG) reacting against P. marinus parasites whereas parasite specific T cell responses were undetectable. Feeding with P. marinus boosted the antibody responses and stimulated specific cellular (IFNγ) immunity to the oyster parasite. Our data indicate the ability of P. marinus parasites to induce systemic immunity in DR4.EA0 mice without causing noticeable pathology, and support rationale grounds for using genetically engineered P. marinus as a new oral vaccine platform to induce systemic immunity against infectious agents. PMID:24498105

  13. Humanized HLA-DR4 mice fed with the protozoan pathogen of oysters Perkinsus marinus (Dermo) do not develop noticeable pathology but elicit systemic immunity.

    PubMed

    Wijayalath, Wathsala; Majji, Sai; Kleschenko, Yuliya; Pow-Sang, Luis; Brumeanu, Teodor D; Villasante, Eileen Franke; Vasta, Gerardo R; Fernández-Robledo, José-Antonio; Casares, Sofia

    2014-01-01

    Perkinsus marinus (Phylum Perkinsozoa) is a marine protozoan parasite responsible for "Dermo" disease in oysters, which has caused extensive damage to the shellfish industry and estuarine environment. The infection prevalence has been estimated in some areas to be as high as 100%, often causing death of infected oysters within 1-2 years post-infection. Human consumption of the parasites via infected oysters is thus likely to occur, but to our knowledge the effect of oral consumption of P. marinus has not been investigated in humans or other mammals. To address the question we used humanized mice expressing HLA-DR4 molecules and lacking expression of mouse MHC-class II molecules (DR4.EA(0)) in such a way that CD4 T cell responses are solely restricted by the human HLA-DR4 molecule. The DR4.EA(0) mice did not develop diarrhea or any detectable pathology in the gastrointestinal tract or lungs following single or repeated feedings with live P. marinus parasites. Furthermore, lymphocyte populations in the gut associated lymphoid tissue and spleen were unaltered in the parasite-fed mice ruling out local or systemic inflammation. Notably, naïve DR4.EA(0) mice had antibodies (IgM and IgG) reacting against P. marinus parasites whereas parasite specific T cell responses were undetectable. Feeding with P. marinus boosted the antibody responses and stimulated specific cellular (IFNγ) immunity to the oyster parasite. Our data indicate the ability of P. marinus parasites to induce systemic immunity in DR4.EA(0) mice without causing noticeable pathology, and support rationale grounds for using genetically engineered P. marinus as a new oral vaccine platform to induce systemic immunity against infectious agents. PMID:24498105

  14. Early host-pathogen interactions in marine bivalves: evidence that the alveolate parasite Perkinsus marinus infects through the oyster mantle during rejection of pseudofeces.

    PubMed

    Allam, Bassem; Carden, Wade E; Ward, J Evan; Ralph, Gina; Winnicki, Sarah; Pales Espinosa, Emmanuelle

    2013-05-01

    Parasites have developed myriad strategies to reach and infect their specific hosts. One of the most common mechanisms for non-vector transmitted parasites to reach the internal host environment is by ingestion during feeding. In this study, we investigated the mechanisms of oyster host colonization by the alveolate Perkinsus marinus and focused on how oysters process infective waterborne P. marinus cells during feeding in order to determine the portal(s) of entry of this parasite to its host. We also compared the infectivity of freely-suspended cells of P. marinus with that of cells incorporated into marine aggregates to link changes in particle processing by the feeding organs with infection success and route. Finally, we evaluated the effect of oyster secretions (mucus) covering the feeding organs on P. marinus physiology because these host factors are involved in the processing of waterborne particles. The ensemble of results shows a unique mechanism for infection by which the parasite is mostly acquired during the feeding process, but not via ingestion. Rather, infection commonly occurs during the rejection of material as pseudofeces before reaching the mouth. The pseudofeces discharge area, a specialized area of the mantle where unwanted particles are accumulated for rejection as pseudofeces, showed significantly higher parasite loads than other host tissues including other parts of the mantle. Aggregated P. marinus cells caused significantly higher disease prevalence and infection intensities when compared to freely-suspended parasite cells. Mucus covering the mantle caused a quick and significant increase in parasite replication rates suggesting rapid impact on P. marinus physiology. A new model for P. marinus acquisition in oysters is proposed. PMID:23274079

  15. Microarray analysis of gene expression in eastern oyster (Crassostrea virginica) reveals a novel combination of antimicrobial and oxidative stress host responses after dermo (Perkinsus marinus) challenge.

    PubMed

    Wang, Shaolin; Peatman, Eric; Liu, Hong; Bushek, David; Ford, Susan E; Kucuktas, Huseyin; Quilang, Jonas; Li, Ping; Wallace, Richard; Wang, Yongping; Guo, Ximing; Liu, Zhanjiang

    2010-12-01

    Dermo disease, caused by Perkinsus marinus, is one of the most severe diseases of eastern oysters, Crassostrea virginica. It causes serious mortalities in both wild and aquacultured oysters. Using existing expressed sequence tag (EST) resources, we developed a 12K in situ oligonucleotide microarray and used it for the analysis of gene expression profiles of oysters during the interactions between P. marinus and its oyster host. Significant gene expression regulation was found at day 30 post-challenge in the eastern oyster. Putative identities of the differentially expressed genes revealed a set of genes involved in several processes including putative antimicrobial defenses, pathogen recognition and uptake, anti-oxidation and apoptosis. Consistent with results obtained from previous, smaller-scale experiments, expression profiles revealed a large set of genes likely involved in an active mitigating response to oxidative stress and apoptosis induced by P. marinus. Additionally, a unique galectin from C. virginica, CvGal, which serves as a preferential receptor for P. marinus trophozoites, was found to be significantly down-regulated in gill tissue of oysters with both light and heavy infection, suggesting an attempt to control parasite uptake and proliferation in the later stages of infection. Potential histone-derived antimicrobial responses to P. marinus were also revealed in the gene expression profiles. PMID:20708691

  16. First report of the protozoan parasite Perkinsus marinus in South America, infecting mangrove oysters Crassostrea rhizophorae from the Paraíba River (NE, Brazil).

    PubMed

    da Silva, Patricia Mirella; Vianna, Rogério Tubino; Guertler, Cristhiane; Ferreira, Liana Pinho; Santana, Lucas Nunes; Fernández-Boo, Sergio; Ramilo, Andrea; Cao, Asunción; Villalba, Antonio

    2013-05-01

    The present work aimed to study the infection by Perkinsus sp. in the mangrove oysters Crassostrea rhizophorae from the estuary of the Paraíba River (Paraíba State, Brazil). Perkinsosis was detected by incubation of oyster gill pieces in Ray's fluid thioglycollate medium. The monthly prevalence values were all above 70%, thus infection was not likely to be a transient event. Perkinsus sp. parasites isolated from eight oysters were propagated in vitro. PCR-RFLP analysis of in vitro cultured cells as well as the sequences of the rDNA ITS region allowed the identification of the in vitro propagated parasites as Perkinsus marinus. Phylogenetic analyses using rDNA ITS region sequences strongly supported the Perkinsus sp. from Paraíba in a monophyletic group with P. marinus. Thus, the results confirmed the species affiliation of Paraíba Perkinsus sp. as P. marinus. This is the first report of P. marinus in Brazil and South America and the first report of P. marinus naturally infecting C. rhizophorae. PMID:23439264

  17. Stone-dwelling actinobacteria Blastococcus saxobsidens, Modestobacter marinus and Geodermatophilus obscurus proteogenomes.

    PubMed

    Sghaier, Haïtham; Hezbri, Karima; Ghodhbane-Gtari, Faten; Pujic, Petar; Sen, Arnab; Daffonchio, Daniele; Boudabous, Abdellatif; Tisa, Louis S; Klenk, Hans-Peter; Armengaud, Jean; Normand, Philippe; Gtari, Maher

    2016-01-01

    The Geodermatophilaceae are unique model systems to study the ability to thrive on or within stones and their proteogenomes (referring to the whole protein arsenal encoded by the genome) could provide important insight into their adaptation mechanisms. Here we report the detailed comparative genome analysis of Blastococcus saxobsidens (Bs), Modestobacter marinus (Mm) and Geodermatophilus obscurus (Go) isolated respectively from the interior and the surface of calcarenite stones and from desert sandy soils. The genome-scale analysis of Bs, Mm and Go illustrates how adaptation to these niches can be achieved through various strategies including 'molecular tinkering/opportunism' as shown by the high proportion of lost, duplicated or horizontally transferred genes and ORFans. Using high-throughput discovery proteomics, the three proteomes under unstressed conditions were analyzed, highlighting the most abundant biomarkers and the main protein factors. Proteomic data corroborated previously demonstrated stone-related ecological distribution. For instance, these data showed starvation-inducible, biofilm-related and DNA-protection proteins as signatures of the microbes associated with the interior, surface and outside of stones, respectively. PMID:26125681

  18. Olfactory-mediated stream-finding behavior of migratory adult sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Vrieze, L.A.; Bergstedt, R.A.; Sorensen, P.W.

    2011-01-01

    Stream-finding behavior of adult sea lamprey (Petromyzon marinus), an anadromous fish that relies on pheromones to locate spawning streams, was documented in the vicinity of an important spawning river in the Great Lakes. Untreated and anosmic migrating sea lampreys were implanted with acoustic transmitters and then released outside the Ocqueoc River. Lampreys swam only at night and then actively. When outside of the river plume, lampreys pursued relatively straight bearings parallel to the shoreline while making frequent vertical excursions. In contrast, when within the plume, lampreys made large turns and exhibited a weak bias towards the river mouth, which one-third of them entered. The behavior of anosmic lampreys resembled that of untreated lampreys outside of the plume, except they pursued a more northerly compass bearing. To locate streams, sea lampreys appear to employ a three-phase odor-mediated strategy that involves an initial search along shorelines while casting vertically, followed by river-water-induced turning that brings them close to the river's mouth, which they then enter using rheotaxis. This novel strategy differs from that of salmonids and appears to offer this poor swimmer adaptive flexibility and suggests ways that pheromonal odors might be used to manage this invasive species.

  19. A New Clarification Method to Visualize Biliary Degeneration During Liver Metamorphosis in Sea Lamprey (Petromyzon marinus)

    PubMed Central

    Chung-Davidson, Yu-Wen; Davidson, Peter J.; Scott, Anne M.; Walaszczyk, Erin J.; Brant, Cory O.; Buchinger, Tyler; Johnson, Nicholas S.; Li, Weiming

    2014-01-01

    Biliary atresia is a rare disease of infancy, with an estimated 1 in 15,000 frequency in the southeast United States, but more common in East Asian countries, with a reported frequency of 1 in 5,000 in Taiwan. Although much is known about the management of biliary atresia, its pathogenesis is still elusive. The sea lamprey (Petromyzon marinus) provides a unique opportunity to examine the mechanism and progression of biliary degeneration. Sea lamprey develop through three distinct life stages: larval, parasitic, and adult. During the transition from larvae to parasitic juvenile, sea lamprey undergo metamorphosis with dramatic reorganization and remodeling in external morphology and internal organs. In the liver, the entire biliary system is lost, including the gall bladder and the biliary tree. A newly-developed method called “CLARITY” was modified to clarify the entire liver and the junction with the intestine in metamorphic sea lamprey. The process of biliary degeneration was visualized and discerned during sea lamprey metamorphosis by using laser scanning confocal microscopy. This method provides a powerful tool to study biliary atresia in a unique animal model. PMID:24962075

  20. Guiding out-migrating juvenile sea lamprey (Petromyzon marinus) with pulsed direct current

    USGS Publications Warehouse

    Johnson, Nicholas S.; Miehls, Scott M.

    2014-01-01

    Non-physical stimuli can deter or guide fish without affecting water flow or navigation and therefore have been investigated to improve fish passage at anthropogenic barriers and to control movement of invasive fish. Upstream fish migration can be blocked or guided without physical structure by electrifying the water, but directional downstream fish guidance with electricity has received little attention. We tested two non-uniform pulsed direct current electric systems, each having different electrode orientations (vertical versus horizontal), to determine their ability to guide out-migrating juvenile sea lamprey (Petromyzon marinus) and rainbow trout (Oncorhynchus mykiss). Both systems guided significantly more juvenile sea lamprey to a specific location in our experimental raceway when activated than when deactivated, but guidance efficiency decreased at the highest water velocities tested. At the electric field setting that effectively guided sea lamprey, rainbow trout were guided by the vertical electrode system, but most were blocked by the horizontal electrode system. Additional research should characterize the response of other species to non-uniform fields of pulsed DC and develop electrode configurations that guide fish over a range of water velocity.

  1. PCB concentrations and activity of sea lamprey Petromyzon marinus vary by sex

    USGS Publications Warehouse

    Madenjian, Charles P.; Johnson, Nicholas S.; Binder, Thomas R.; Rediske, Richard R.; O'Keefe, James P.

    2013-01-01

    We determined the polychlorinated biphenyl (PCB) concentrations of 40 male and 40 female adult sea lampreys Petromyzon marinus captured in the Cheboygan River, a tributary to Lake Huron, during May 2011. In addition, we performed a laboratory experiment using passive integrated transponder tags to determine whether male adult sea lampreys were more active than female adult sea lampreys. Sex had a significant effect on PCB concentration, and PCB concentration at a given level of sea lamprey condition was approximately 25 % greater in males than in females. Adjusting for the difference in condition between the sexes, males averaged a 17 % greater PCB concentration compared with females. Results from the laboratory experiment indicated that males were significantly more active than females. The observed sex difference in PCB concentrations was not due to female sea lampreys releasing eggs at spawning because the sea lamprey is semelparous, and we caught the sea lampreys before spawning. Rather, we attributed the sex difference in PCB concentrations to a greater rate of energy expenditure in males compared with females. We proposed that this greater rate of energy expenditure was likely due to greater activity. Our laboratory experiment results supported this hypothesis. A greater resting metabolic rate may also have contributed to a greater rate of energy expenditure. Our findings should eventually be applicable toward improving control of sea lamprey, a pest responsible for considerable damage to fisheries in lakes where it is not native.

  2. Sea lamprey (Petromyzon marinus) parasite-host interactions in the Great Lakes

    USGS Publications Warehouse

    Bence, James R.; Bergstedt, Roger A.; Christie, Gavin C.; Cochran, Phillip A.; Ebener, Mark P.; Koonce, Joseph F.; Rutter, Michael A.; Swink, William D.

    2003-01-01

    Prediction of how host mortality responds to efforts to control sea lampreys (Petromyzon marinus) is central to the integrated management strategy for sea lamprey (IMSL) in the Great Lakes. A parasite-host submodel is used as part of this strategy, and this includes a type-2 multi-species functional response, a developmental response, but no numerical response. General patterns of host species and size selection are consistent with the model assumptions, but some observations appear to diverge. For example, some patterns in sea lamprey marking on hosts suggest increases in selectivity for less preferred hosts and lower host survival when preferred hosts are scarce. Nevertheless, many of the IMSL assumptions may be adequate under conditions targeted by fish community objectives. Of great concern is the possibility that the survival of young parasites (parasitic-phase sea lampreys) varies substantially among lakes or over time. Joint analysis of abundance estimates for parasites being produced in streams and returning spawners could address this. Data on sea lamprey marks is a critical source of information on sea lamprey activity and potential effects. Theory connecting observed marks to sea lamprey feeding activity and host mortality is reviewed. Uncertainties regarding healing and attachment times, the probability of hosts surviving attacks, and problems in consistent classification of marks have led to widely divergent estimates of damages caused by sea lamprey. Laboratory and field studies are recommended to provide a firmer linkage between host blood loss, host mortality, and observed marks on surviving hosts, so as to improve estimates of damage.

  3. Daytime avoidance of chemosensory alarm cues by adult sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Di Rocco, Richard; Belanger, Cowan; Imre, István; Brown, Grant; Johnson, Nicholas S.

    2014-01-01

    Sea lamprey (Petromyzon marinus) avoid damage-released and predator chemosensory cues at night, but their response to these cues during the day is unknown. Here, we explored (i) whether sea lamprey avoid these cues during the day and (ii) the effect of water temperature on the avoidance of chemosensory alarm cues in two diurnal laboratory experiments. We hypothesized that daytime activity would be temperature-dependent and that only sea lamprey vulnerable to predation (i.e., not hiding) would behaviourally respond to chemosensory alarm cues. Ten groups of ten sea lamprey were exposed to one of a variety of potential chemosensory cues. The experiments were conducted over a range of temperatures to quantify the effect of temperature on avoidance behaviour. Consistent with our hypothesis, a higher proportion of animals were active during daytime as water temperature increased. Moving sea lamprey showed an avoidance response to 2-phenylethylamine (a compound found in mammalian urine) and human saliva once water temperatures had risen to mean (±SD) = 13.7 (±1.4) °C. Resting and hiding sea lamprey did not show an avoidance response to any of the experimental stimuli.

  4. Label-free microscopy and stress responses reveal the functional organization of Pseudodiaptomus marinus copepod myofibrils.

    PubMed

    Ibrahim, Ali; Hage, Charles Henri; Souissi, Anissa; Leray, Aymeric; Héliot, Laurent; Souissi, Sami; Vandenbunder, Bernard

    2015-08-01

    Pseudodiaptomus marinus copepods are small crustaceans living in estuarine areas endowed with exceptional swimming and adaptative performances. Since the external cuticle acts as an impermeable barrier for most dyes and molecular tools for labeling copepod proteins with fluorescent tags are not available, imaging cellular organelles in these organisms requires label free microscopy. Complementary nonlinear microscopy techniques have been used to investigate the structure and the response of their myofibrils to abrupt changes of temperature or/and salinity. In contrast with previous observations in vertebrates and invertebrates, the flavin autofluorescence which is a signature of mitochondria activity and the Coherent Anti-Stokes Raman Scattering (CARS) pattern assigned to T-tubules overlapped along myofibrils with the second harmonic generation (SHG) striated pattern generated by myosin tails in sarcomeric A bands. Temperature jumps from 18 to 4 °C or salinity jumps from 30 to 15 psu mostly affected flavin autofluorescence. Severe salinity jumps from 30 to 0 psu dismantled myofibril organization with major changes both in the SHG and CARS patterns. After a double stress (from 18 °C/30 psu to 4° C/0 psu) condensed and distended regions appeared within single myofibrils, with flavin autofluorescence bands located between sarcomeric A bands. These results shed light on the interactions between the different functional compartments which provide fast acting excitation-contraction coupling and adequate power supply in copepods muscles. PMID:26057347

  5. A new clarification method to visualize biliary degeneration during liver metamorphosis in sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Chung-Davidson, Yu-Wen; Davidson, Peter J.; Scott, Anne M.; Walaszczyk, Erin J.; Brant, Cory O.; Buchinger, Tyler; Johnson, Nicholas S.; Li, Weiming

    2014-01-01

    Biliary atresia is a rare disease of infancy, with an estimated 1 in 15,000 frequency in the southeast United States, but more common in East Asian countries, with a reported frequency of 1 in 5,000 in Taiwan. Although much is known about the management of biliary atresia, its pathogenesis is still elusive. The sea lamprey (Petromyzon marinus) provides a unique opportunity to examine the mechanism and progression of biliary degeneration. Sea lamprey develop through three distinct life stages: larval, parasitic, and adult. During the transition from larvae to parasitic juvenile, sea lamprey undergo metamorphosis with dramatic reorganization and remodeling in external morphology and internal organs. In the liver, the entire biliary system is lost, including the gall bladder and the biliary tree. A newly-developed method called “CLARITY” was modified to clarify the entire liver and the junction with the intestine in metamorphic sea lamprey. The process of biliary degeneration was visualized and discerned during sea lamprey metamorphosis by using laser scanning confocal microscopy. This method provides a powerful tool to study biliary atresia in a unique animal model.

  6. Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus).

    PubMed

    Walaszczyk, Erin J; Johnson, Nicholas S; Steibel, Juan Pedro; Li, Weiming

    2013-06-01

    Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p < 0.05) and cause increases in activity during several daytime hours in preovulated and ovulated females. These results are one of the first examples of how sex pheromones modulate a locomotor rhythm in a vertebrate, and they suggest that the interaction between maturity stage and sex pheromone exposure contributes to the differential locomotor rhythms found in adult female sea lamprey. This phenomenon may contribute to the reproductive synchrony of mature adults, thus increasing reproductive success in this species. PMID:23735501

  7. Response of larval sea lampreys (Petromyzon marinus) to pulsed DC electrical stimuli in laboratory experiments

    USGS Publications Warehouse

    Bowen, Anjanette K.; Weisser, John W.; Bergstedt, Roger A.; Famoye, Felix

    2003-01-01

    Four electrical factors that are used in pulsed DC electrofishing for larval sea lampreys (Petromyzon marinus) were evaluated in two laboratory studies to determine the optimal values to induce larval emergence over a range of water temperatures and conductivities. Burrowed larvae were exposed to combinations of pulsed DC electrical factors including five pulse frequencies, three pulse patterns, and two levels of duty cycle over a range of seven voltage gradients in two separate studies conducted at water temperatures of 10, 15, and 20°C and water conductivities of 25, 200, and 900 μS/cm. A four-way analysis of variance was used to determine significant (α = 0.05) influences of each electrical factor on larval emergence. Multiple comparison tests with Bonferroni adjustments were used to determine which values of each factor resulted in significantly higher emergence at each temperature and conductivity. Voltage gradient and pulse frequency significantly affected emergence according to the ANOVA model at each temperature and conductivity tested. Duty cycle and pulse pattern generally did not significantly influence the model. Findings suggest that a setting of 2.0 V/cm, 3 pulses/sec, 10% duty, and 2:2 pulse pattern seems the most promising in waters of medium conductivity and across a variety of temperatures. This information provides a basis for understanding larval response to pulsed DC electrofishing gear factors and identifies electrofisher settings that show promise to increase the efficiency of the gear during assessments for burrowed sea lamprey larvae.

  8. Chemosterilization of male sea lampreys (Petromyzon marinus) does not affect sex pheromone release

    USGS Publications Warehouse

    Siefkes, Michael J.; Bergstedt, Roger A.; Twohey, Michael B.; Li, Weiming

    2003-01-01

    Release of males sterilized by injection with bisazir is an important experimental technique in management of sea lamprey (Petromyzon marinus), an invasive, nuisance species in the Laurentian Great Lakes. Sea lampreys are semelparous and sterilization can theoretically eliminate a male's reproductive capacity and, if the ability to obtain mates is not affected, waste the sex products of females spawning with him. It has been demonstrated that spermiating males release a sex pheromone that attracts ovulating females. We demonstrated that sterilized, spermiating males also released the pheromone and attracted ovulating females. In a two-choice maze, ovulating females increased searching behavior and spent more time in the side of the maze containing chemical stimuli from sterilized, spermiating males. This attraction response was also observed in spawning stream experiments. Also, electro-olfactograms showed that female olfactory organs were equally sensitive to chemical stimuli from sterilized and nonsterilized, spermiating males. Finally, fast atom bombardment mass spectrometry showed that extracts from water conditioned with sterilized and nonsterilized, spermiating males contained the same pheromonal molecule at similar levels. We concluded that injection of bisazir did not affect the efficacy of sex pheromone in sterilized males.

  9. A synthesized mating pheromone component increases adult sea lamprey (Petromyzon marinus) trap capture in management scenarios

    USGS Publications Warehouse

    Johnson, Nicholas S.; Siefkes, Michael J.; Wagner, C. Michael; Dawson, Heather; Wang, Huiyong; Steeves, Todd; Twohey, Michael; Li, Weiming

    2013-01-01

    Application of chemical cues to manipulate adult sea lamprey (Petromyzon marinus) behavior is among the options considered for new sea lamprey control techniques in the Laurentian Great Lakes. A male mating pheromone component, 7a,12a,24-trihydroxy-3-one-5a-cholan-24-sulfate (3kPZS), lures ovulated female sea lamprey upstream into baited traps in experimental contexts with no odorant competition. A critical knowledge gap is whether this single pheromone component influences adult sea lamprey behavior in management contexts containing free-ranging sea lampreys. A solution of 3kPZS to reach a final in-stream concentration of 10-12 mol·L-1 was applied to eight Michigan streams at existing sea lamprey traps over 3 years, and catch rates were compared between paired 3kPZS-baited and unbaited traps. 3kPZS-baited traps captured significantly more sexually immature and mature sea lampreys, and overall yearly trapping efficiency within a stream averaged 10% higher during years when 3kPZS was applied. Video analysis of a trap funnel showed that the likelihood of sea lamprey trap entry after trap encounter was higher when the trap was 3kPZS baited. Our approach serves as a model for the development of similar control tools for sea lamprey and other aquatic invaders.

  10. Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Walaszczyk, Erin J.; Johnson, Nicholas S.; Steibel, Juan Pedro; Li, Weiming

    2013-01-01

    Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p < 0.05) and cause increases in activity during several daytime hours in preovulated and ovulated females. These results are one of the first examples of how sex pheromones modulate a locomotor rhythm in a vertebrate, and they suggest that the interaction between maturity stage and sex pheromone exposure contributes to the differential locomotor rhythms found in adult female sea lamprey. This phenomenon may contribute to the reproductive synchrony of mature adults, thus increasing reproductive success in this species.

  11. Multiple functions of a multi-component mating pheromone in sea lamprey Petromyzon marinus

    USGS Publications Warehouse

    Johnson, N.S.; Yun, S.-S.; Buchinger, T.J.; Li, W.

    2012-01-01

    The role of the C24 sulphate in the mating pheromone component, 7α,12α,24-trihydroxy-5α-cholan-3-one 24-sulphate (3kPZS), to specifically induce upstream movement in ovulated female sea lampreys Petromyzon marinus was investigated. 7α,12α-dihydroxy-5α-cholan-3-one 24-oic acid (3kACA), a structurally similar bile acid released by spermiated males, but lacking the C24 sulphate ester, was tested in bioassays at concentrations between 10−11 and 10−14 molar (M). 3kACA did not induce upstream movement in females or additional reproductive behaviours. In contrast, spermiated male washings induced upstream movement, prolonged retention on a nest and induced an array of nesting behaviours. Differential extraction and elution by solid-phase extraction resins showed that components other than 3kPZS + 3kACA are necessary to retain females on nests and induce nest cleaning behaviours. All pheromone components, including components in addition to 3kPZS + 3kACA that retain females and induce nest cleaning behaviours were released from the anterior region of the males, as had been reported for 3kPZS. It is concluded that the sea lamprey male mating pheromone has multiple functions and is composed of multiple components.

  12. Mark-recapture population estimates of parasitic sea lampreys (Petromyzon marinus) in Lake Huron

    USGS Publications Warehouse

    Bergstedt, Roger A.; McDonald, Rodney B.; Mullett, Katherine M.; Wright, Gregory M.; Swink, William D.; Burnham, Kenneth P.

    2003-01-01

    Metamorphosed sea lampreys (Petromyzon marinus) were collected and marked at two points in their life cycle. Recently metamorphosed juveniles were collected from streams, marked with coded wire tags, and returned to migrate to the Great Lakes. Juveniles already in the lakes and feeding on teleost hosts were obtained from incidental catches by sport or commercial fisheries. Sea lampreys in the Great Lakes spend only 1 feeding year as parasites, and marked animals were recaptured during the spawning runs. For one marked group in each of four parasitic cohorts (feeding years 1991 to 1994) and two marked groups in each of three cohorts (feeding years 1998 to 2000) we recovered from 1.1 to 10.2 percent of marked animals. The number of metamorphosed animals present in autumn before migration to Lake Huron was estimated for five cohorts, with estimates ranging from 639 to 803 thousand. The number of feeding, parasitic animals present in Lake Huron in mid summer was estimated for five cohorts, with estimates ranging from 515,000 to 2,342,000. The larger estimates later in the parasitic year suggested that animals collected and marked from sport or commercial fisheries did not survive at the same rate as unmarked animals. It is recommended that only estimates from recaptures of animals marked in the streams before migration be used until it can be established why survival of juveniles obtained from sport or commercial fisheries might be affected.

  13. A spatial age-structured model for describing sea lamprey (Petromyzon marinus) population dynamics

    USGS Publications Warehouse

    Robinson, Jason M.; Wilberg, Michael J.; Adams, Jean V.; Jones, Michael L.

    2013-01-01

    The control of invasive sea lampreys (Petromyzon marinus) presents large scale management challenges in the Laurentian Great Lakes. No modeling approach has been developed that describes spatial dynamics of lamprey populations. We developed and validated a spatial and age-structured model and applied it to a sea lamprey population in a large river in the Great Lakes basin. We considered 75 discrete spatial areas, included a stock-recruitment function, spatial recruitment patterns, natural mortality, chemical treatment mortality, and larval metamorphosis. Recruitment was variable, and an upstream shift in recruitment location was observed over time. From 1993–2011 recruitment, larval abundance, and the abundance of metamorphosing individuals decreased by 80, 84, and 86%, respectively. The model successfully identified areas of high larval abundance and showed that areas of low larval density contribute significantly to the population. Estimated treatment mortality was less than expected but had a large population-level impact. The results and general approach of this work have applications for sea lamprey control throughout the Great Lakes and for the restoration and conservation of native lamprey species globally.

  14. Classification of sea lamprey (Petromyzon marinus) attack marks on Great Lakes lake trout (Salvelinus namaycush)

    USGS Publications Warehouse

    King, Everett Louis, Jr.

    1980-01-01

    Criteria for the classification of marks inflicted by sea lamprey (Petromyzon marinus) into nine categories were developed from laboratory studies in an attempt to refine the classification system used in field assessment work. These criteria were based on characteristics of the attachment site that could be identified under field conditions by unaided visual means and by touching the attachment site. Healing of these marks was somewhat variable and was influenced by the size of lamprey, duration of attachment, severity of the wound at lamprey detachment, season and water temperature, and by other less obvious factors. Even under laboratory conditions staging of some wounds was difficult, especially at low water temperatures. If these criteria are to be used effectively and with precision in the field, close examination of individual fish may be required. If the feeding and density of specific year-classes of sea lampreys are to be accurately assessed on an annual basis, close attention to the wound size (as it reflects the size of the lamprey's oral disc) and character of wounds on fish will be required as well as consideration of the season of the year in which they are observed.Key words: sea lamprey, attack marks, lake trout, Great Lakes

  15. Glutamine Synthetase Sensitivity to Oxidative Modification during Nutrient Starvation in Prochlorococcus marinus PCC 9511

    PubMed Central

    Gómez-Baena, Guadalupe; Domínguez-Martín, María Agustina; Donaldson, Robert P.; García-Fernández, José Manuel; Diez, Jesús

    2015-01-01

    Glutamine synthetase plays a key role in nitrogen metabolism, thus the fine regulation of this enzyme in Prochlorococcus, which is especially important in the oligotrophic oceans where this marine cyanobacterium thrives. In this work, we studied the metal-catalyzed oxidation of glutamine synthetase in cultures of Prochlorococcus marinus strain PCC 9511 subjected to nutrient limitation. Nitrogen deprivation caused glutamine synthetase to be more sensitive to metal-catalyzed oxidation (a 36% increase compared to control, non starved samples). Nutrient starvation induced also a clear increase (three-fold in the case of nitrogen) in the concentration of carbonyl derivatives in cell extracts, which was also higher (22%) upon addition of the inhibitor of electron transport, DCMU, to cultures. Our results indicate that nutrient limitations, representative of the natural conditions in the Prochlorococcus habitat, affect the response of glutamine synthetase to oxidative inactivating systems. Implications of these results on the regulation of glutamine synthetase by oxidative alteration prior to degradation of the enzyme in Prochlorococcus are discussed. PMID:26270653

  16. Agromyces marinus sp. nov., a novel actinobacterium isolated from sea sediment.

    PubMed

    Hamada, Moriyuki; Shibata, Chiyo; Tamura, Tomohiko; Suzuki, Ken-ichiro

    2014-10-01

    Two novel Gram-stain-positive actinobacteria, designated H23-8(T) and H23-19, were isolated from a sea sediment sample and their taxonomic positions were investigated by a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that these isolates were closely related to the members of the genus Agromyces, with similarity range of 94.5-97.4%. Strains H23-8(T) and H23-19 contained L-2,4-diaminobutyric acid, D-alanine, D-glutamic acid and glycine in their peptidoglycan. The predominant menaquinones were MK-13 and MK-12, and the major fatty acids were anteiso-C(15:0), anteiso-C(17:0) and iso-C(16:0). The DNA G+C content was 72.3-72.5 mol%. The chemotaxonomic characteristics of the isolates matched those described for members of the genus Agromyces. The results of phylogenetic analysis and DNA-DNA hybridization, along with differences in phenotypic characteristics between strains H23-8(T) and H23-19 and the species of the genus Agromyces with validly published names, indicated that the two isolates should be assigned to a novel species of the genus Agromyces, for which the name Agromyces marinus sp. nov. is proposed; the type strain is H23-8(T) (=NBRC 109019(T)=DSM 26151(T)). PMID:24824819

  17. Measuring Energetics and Behaviour Using Accelerometry in Cane Toads Bufo marinus

    PubMed Central

    Halsey, Lewis G.; White, Craig R.

    2010-01-01

    Cane toads Bufo marinus were introduced to Australia as a control agent but now have a rapidly progressing invasion front and damage new habitats they enter. Predictive models that can give expansion rates as functions of energy supply and feeding ground distribution could help to maximise control efficiency but to date no study has measured rates of field energy expenditure in an amphibian. In the present study we used the accelerometry technique to generate behavioural time budgets and, through the derivation of ODBA (overall dynamic body acceleration), to obtain estimates of energetics in free ranging cane toads. This represents the first time that accelerometers have been used to not only quantify the behaviour of animals but also assign to those behaviours rates of energy expenditure. Firstly, laboratory calibrations between ODBA and metabolic rate were obtained and used to generate a common prediction equation for the subject toads (R2 = 0.74). Furthermore, acceleration data recorded during different behaviours was studied to ascertain threshold values for objectively defining behaviour categories. Importantly, while subsequent accelerometer field deployments were relatively short they agreed with previous studies on the proportion of time that cane toads locomote yet suggest that the metabolic rate of cane toads in the wild may sometimes be considerably higher than might be assumed based on data for other species. PMID:20422048

  18. Larval mortality rates and population dynamics of Lesser Sandeel ( Ammodytes marinus) in the northwestern North Sea

    NASA Astrophysics Data System (ADS)

    Heath, Michael R.; Rasmussen, Jens; Bailey, Martin C.; Dunn, John; Fraser, John; Gallego, Alejandro; Hay, Stephen J.; Inglis, Michelle; Robinson, Susan

    2012-05-01

    Intense fishing of a stock of sandeels ( Ammodytes marinus) on the sand banks off the Firth of Forth, northeast Scotland, during the 1990s led to a decline in catch per unit effort to uneconomic levels and collateral failures of piscivorous seabird breeding success at nearby colonies. A prohibition on fishing in 1999 was followed by a short-term recovery of stock biomass, but then a sustained decline to very low levels of abundance. Demographic survey data show that despite the decline in stock, recruit abundance was maintained implying an increasing larval survival rate, and that the stock decline was not due to recruitment failure. To verify this hypothesis we analysed a 10-year long data set of weekly catches of sandeel larvae at a nearby plankton monitoring site to determine the patterns of larval mortality and dispersal. We found that the loss rate of larvae up to 20 d age decreased over time, corresponding with the trend in survival rate implied by the stock demography data. The pattern of loss rate in relation to hatchling abundance implied that mortality may have been density dependent. Our study rules out increased larval mortality as the primary cause of decline in the sandeel stock.

  19. Acute osmotic tolerance of cultured cells of the oyster pathogen Perkinsus marinus (Apicomplexa:Perkinsida).

    PubMed

    Burreson, E M; Ragone Calvo, L M; La Peyre, J F; Counts, F; Paynter, K T

    1994-11-01

    Cultured Perkinsus marinus cells were exposed for 24 hr to salinities of 0, 3, 6, 9, 12 and 22 ppt at temperatures of 1, 5, 10, 15 and 28 degrees C in artificial seawater (ASW) and to the same salinities at 28 degrees C in ASW with the osmotic concentration adjusted with sucrose to the equivalent of 22 ppt. At 28 degrees C mortality increased as salinity decreased below 22 ppt. Mortality was greater than 99% at 0 ppt and greater than 90% at 3 ppt. Mortality was 70% at 6 ppt, 43% at 9 ppt and 20% at 12 ppt. Mortality was low (< 5%) and equal to that at 22 ppt in all treatments where osmotic concentration was maintained with sucrose. Mortality occurred rapidly, within 5 min of exposure to experimental conditions. In the region where mortality was most sensitive to salinity changes (6-12 ppt), lower temperature caused an increase in mortality, but the temperature effect was significant only at 9 ppt. PMID:8529003

  20. Characterization of Somatically-Eliminated Genes During Development of the Sea Lamprey (Petromyzon marinus).

    PubMed

    Bryant, Stephanie A; Herdy, Joseph R; Amemiya, Chris T; Smith, Jeramiah J

    2016-09-01

    The sea lamprey (Petromyzon marinus) is a basal vertebrate that undergoes developmentally programmed genome rearrangements (PGRs) during early development. These events facilitate the elimination of ∼20% of the genome from the somatic cell lineage, resulting in distinct somatic and germline genomes. Thus far only a handful of germline-specific genes have been definitively identified within the estimated 500 Mb of DNA that is deleted during PGR, although a few thousand germline-specific genes are thought to exist. To improve our understanding of the evolutionary/developmental logic of PGR, we generated computational predictions to identify candidate germline-specific genes within a new transcriptomic dataset derived from adult germline and the early embryonic stages during which PGR occurs. Follow-up validation studies identified 44 germline-specific genes and further characterized patterns of transcription and DNA loss during early embryogenesis. Expression analyses reveal that many of these genes are differentially expressed during early embryogenesis and presumably function in the early development of the germline. Ontology analyses indicate that many of these germline-specific genes play known roles in germline development, pluripotency, and oncogenesis (when misexpressed). These studies provide support for the theory that PGR serves to segregate molecular functions related to germline development/pluripotency in order to prevent their potential misexpression in somatic cells. This larger set of eliminated genes also allows us to extend the evolutionary/developmental breadth of this theory, as some deleted genes (or their gnathostome homologs) appear to be associated with the early development of somatic lineages, perhaps through the evolution of novel functions within gnathostome lineages. PMID:27288344

  1. Host selection and lethality of attacks by sea lampreys (Petromyzon marinus) in laboratory studies

    USGS Publications Warehouse

    Swink, William D.

    2003-01-01

    Parasitic-phase sea lampreys (Petromyzon marinus) are difficult to study in the wild. A series of laboratory studies (1984-1995) of single attacks on lake trout (Salvelinus namaycush), rainbow trout (Oncorhynchus mykiss), and burbot (Lota lota) examined host size selection; determined the effects of host size, host species, host strain, and temperature on host mortality; and estimated the weight of hosts killed per lamprey. Rainbow trout were more able and burbot less able to survive attacks than lake trout. Small sea lampreys actively selected the larger of two small hosts; larger sea lampreys attacked larger hosts in proportion to the hosts' body sizes, but actively avoided shorter hosts (a?? 600 mm) when larger were available. Host mortality was significantly less for larger (43-44%) than for smaller hosts (64%). However, the yearly loss of hosts per sea lamprey was less for small hosts (range, 6.8-14.2 kg per sea lamprey) than larger hosts (range, 11.4-19.3 kg per sea lamprey). Attacks at the lower of two temperature ranges (6.1-11.8A?C and 11.1-15.0A?C) did not significantly reduce the percentage of hosts killed (54% vs. 69%, p > 0.21), but longer attachment times at lower temperatures reduced the number of hosts attacked (33 vs. 45), and produced the lowest loss of hosts (6.6 kg per sea lamprey). Low temperature appeared to offset other factors that increase host mortality. Reanalysis of 789 attacks pooled from these studies, using forward stepwise logistic regression, also identified mean daily temperature as the dominant factor affecting host mortality. Observations in Lakes Superior, Huron, and Ontario support most laboratory results.

  2. Differential Effects of Sex Pheromone Compounds on Adult Female Sea Lamprey (Petromyzon marinus) Locomotor Patterns.

    PubMed

    Walaszczyk, Erin J; Goheen, Benjamin B; Steibel, Juan Pedro; Li, Weiming

    2016-06-01

    Synchronization of male and female locomotor activity plays a critical role in ensuring reproductive success, especially in semelparous species. The goal of this study was to elucidate the effects of individual chemical signals, or pheromones, on the locomotor activity in the sea lamprey (Petromyzon marinus). In their native habitat, adult preovulated females (POF) and ovulated females (OF) are exposed to sex pheromone compounds that are released from spermiated males and attract females to nests during their migration and spawning periods. In this study, locomotor activity of individual POF and OF was measured hourly in controlled laboratory conditions using an automated video-tracking system. Differences in the activity between a baseline day (no treatment exposure) and a treatment day (sex pheromone compound or control exposure) were examined for daytime and nighttime periods. Results showed that different pheromone compound treatments affected both POF and OF sea lamprey (p < 0.05) but in different ways. Spermiated male washings (SMW) and one of its main components, 7α,12α,24-trihydroxy-5α-cholan-3-one 24 sulfate (3kPZS), decreased activity of POF during the nighttime. SMW also reduced activity in POF during the daytime. In contrast, SMW increased activity of OF during the daytime, and an additional compound found in SMW, petromyzonol sulfate (PZS), decreased the activity during the nighttime. In addition, we examined factors that allowed us to infer the overall locomotor patterns. SMW increased the maximum hourly activity during the daytime, decreased the maximum hourly activity during the nighttime, and reduced the percentage of nocturnal activity in OF. Our findings suggest that adult females have evolved to respond to different male compounds in regards to their locomotor activity before and after final maturation. This is a rare example of how species-wide chemosensory stimuli can affect not only the amounts of activity but also the overall locomotor

  3. Anadromous sea lampreys (Petromyzon marinus) are ecosystem engineers in a spawning tributary

    USGS Publications Warehouse

    Hogg, Robert S.; Coghlan Jr., Stephen M.; Zydlewski, Joseph; Simon, Kevin S.

    2014-01-01

    Sea lampreys (Petromyzon marinus) disturb the substratum during nest construction and alter the physical habitat, potentially affecting other stream organisms. We quantified differences in depth, velocity, fine-sediment coverage, embeddedness, intragravel permeability and benthic invertebrate assemblages (density and diversity) among nest mounds, nest pits and undisturbed reference locations over a 4-month period after June spawning. In 2010 and 2011, immediate and persistent effects of nest construction were assessed in summer (July) and in autumn (late September to early October), respectively. Randomly selected nests were sampled annually (25 each in summer and autumn). Nest construction increased stream-bed complexity by creating and juxtaposing shallow, swift, rocky habitat patches with deep, slow, sandy habitat patches. Mounds had a 50–143% less cover of fine sediment, and a 30–62% reduction in embeddedness, compared to pits and reference locations. These physical changes persisted into the autumn (almost 4 months). Five insect families contributed 74% of the benthic invertebrate abundance: Chironomidae (27%), Hydropsychidae (26%), Heptageniidae (8%), Philopotamidae (7%) and Ephemerellidae (6%). Densities of Hydropsychidae, Philopotamidae and Heptageniidae were up to 10 times greater in mounds than in pits and adjacent reference habitat. In summer, mounds had twice the density of Chironomidae than did pits, and 1.5 times more than reference habitats, but densities were similar among the habitats in autumn. These results suggest that spawning sea lampreys are ecosystem engineers. The physical disturbance caused by nest-building activity was significant and persistent, increasing habitat heterogeneity and favouring pollution-sensitive benthic invertebrates and, possibly, drift-feeding fish.

  4. Moonlight receptor of the "1-h-midge" Clunio marinus studied by micro-XRF

    NASA Astrophysics Data System (ADS)

    Falkenberg, G.; Fleissner, Ge; Neumann, D.; Wellenreuther, G.; Alraun, P.; Fleissner, Gue

    2013-10-01

    Melanin is a pigment widely occurring in animals, plants, fungi and algae. It does not only colour skin, hair and eyes but serves mainly as photoprotectant and prevents overload with minerals induced by inflammations, infections and degenerative diseases. Therefore, the mechanisms underlying melanisation gained increasing interest in the field of biomedical research and clinic. So far, the processes of melanogenesis are only partly analysed, nearly nothing is known on a putative switch between melanins of different types. Here we offer a model organism to study these mechanisms as part of a naturally cycling change of transparency of the retinal shielding pigment. A marine midge, Clunio marinus, living in coastal regions, underlies a complex timing of its development by solar and lunar climatic periodicities, which synchronise biological clocks. The question was how the animals can discriminate changing sunlight from moonlight intensities. For the first time, we could show a "moonlight window" in the larval ocelli of this midge, and propose a hypothesis on the underlying mechanisms. Driven by a lunar clock the image forming ocelli become transparent and convert during moonlit nights to a sensitive photometer, which can record the dynamics of environmental light. High resolution X-ray fluorescence (XRF) measurements of the distribution of trace minerals in single melanosomes combined with their fine structural details in various states of the lunar cycle provide a first insight into the enzymatic pathways for the generation of a dark melanin (like eumelanin) and a light coloured melanin (like phaeomelanin). Essential advantage of this approach is the spatial and temporal resolution of the metals associated with melanisation processes, which could never before be demonstrated in these details. The data may stimulate further research projects in biomedicine.

  5. Cellular and Molecular Features of Developmentally Programmed Genome Rearrangement in a Vertebrate (Sea Lamprey: Petromyzon marinus)

    PubMed Central

    Timoshevskiy, Vladimir A.; Herdy, Joseph R.; Keinath, Melissa C.; Smith, Jeramiah J.

    2016-01-01

    The sea lamprey (Petromyzon marinus) represents one of the few vertebrate species known to undergo large-scale programmatic elimination of genomic DNA over the course of its normal development. Programmed genome rearrangements (PGRs) result in the reproducible loss of ~20% of the genome from somatic cell lineages during early embryogenesis. Studies of PGR hold the potential to provide novel insights related to the maintenance of genome stability during the cell cycle and coordination between mechanisms responsible for the accurate distribution of chromosomes into daughter cells, yet little is known regarding the mechanistic basis or cellular context of PGR in this or any other vertebrate lineage. Here we identify epigenetic silencing events that are associated with the programmed elimination of DNA and describe the spatiotemporal dynamics of PGR during lamprey embryogenesis. In situ analyses reveal that the earliest DNA methylation (and to some extent H3K9 trimethylation) events are limited to specific extranuclear structures (micronuclei) containing eliminated DNA. During early embryogenesis a majority of micronuclei (~60%) show strong enrichment for repressive chromatin modifications (H3K9me3 and 5meC). These analyses also led to the discovery that eliminated DNA is packaged into chromatin that does not migrate with somatically retained chromosomes during anaphase, a condition that is superficially similar to lagging chromosomes observed in some cancer subtypes. Closer examination of “lagging” chromatin revealed distributions of repetitive elements, cytoskeletal contacts and chromatin contacts that provide new insights into the cellular mechanisms underlying the programmed loss of these segments. Our analyses provide additional perspective on the cellular and molecular context of PGR, identify new structures associated with elimination of DNA and reveal that PGR is completed over the course of several successive cell divisions. PMID:27341395

  6. Agriculture Alters Gonadal Form and Function in the Toad Bufo marinus

    PubMed Central

    McCoy, Krista A.; Bortnick, Lauriel J.; Campbell, Chelsey M.; Hamlin, Heather J.; Guillette, Louis J.; St. Mary, Colette M.

    2008-01-01

    Background Many agricultural contaminants disrupt endocrine systems of wildlife. However, evidence of endocrine disruption in wild amphibians living in agricultural areas has been controversial. Typically, studies on the effects of pollutants on wildlife attempt to compare polluted with unpolluted sites. Objectives We took a novel approach to address this question by explicitly quantifying the relationship between gonadal abnormalities and habitats characterized by differing degrees of agricultural activity. Methods We quantified the occurrence of gonadal abnormalities and measures of gonadal function in at least 20 giant toads (Bufo marinus) from each of five sites that occur along a gradient of increasing agricultural land use from 0 to 97%. Results The number of abnormalities and frequency of intersex gonads increased with agriculture in a dose-dependent fashion. These gonadal abnormalities were associated with altered gonadal function. Testosterone, but not 17β-estradiol, concentrations were altered and secondary sexual traits were either feminized (increased skin mottling) or demasculinized (reduced forearm width and nuptial pad number) in intersex toads. Based on the end points we examined, female morphology and physiology did not differ across sites. However, males from agricultural areas had hormone concentrations and secondary sexual traits that were intermediate between intersex toads and non-agricultural male toads. Skin coloration at the most agricultural site was not sexually dimorphic; males had female coloration. Conclusions Steroid hormone concentrations and secondary sexual traits correlate with reproductive activity and success, so affected toads likely have reduced reproductive success. These reproductive abnormalities could certainly contribute to amphibian population declines occurring in areas exposed to agricultural contaminants. PMID:19057706

  7. Electrophysiological properties of the tongue epithelium of the toad Bufo marinus.

    PubMed

    Baker, Timothy K; Rios, Karina; Hillyard, Stanley D

    2002-07-01

    The dorsal lingual epithelium from the tongue of the toad Bufo marinus was mounted in an Ussing-type chamber, and the short-circuit current (I(sc)) was measured using a low-noise voltage clamp. With NaCl Ringer bathing the mucosal and serosal surfaces of the isolated tissue, an outwardly directed (mucosa-positive) I(sc) was measured that averaged -10.71+/-0.82 microA cm(-2) (mean +/- S.E.M., N=24) with a resistance of 615+/-152 Omega cm(2) (mean +/- S.E.M., N=10). Substitution of chloride with sulfate as the anion produced no significant change in I(sc). Fluctuation analysis with either NaCl or Na(2)SO(4) Ringer bathing both sides of the tissue revealed a spontaneous Lorentzian component, suggesting that the I(sc) was the result of K(+) secretion through spontaneously fluctuating channels in the apical membrane of the epithelium. This hypothesis was supported by the reversible inhibition of I(sc) by Ba(2+) added to the mucosal Ringer. Analysis of the kinetics of Ba(2+) inhibition of I(sc) indicates that there might be more than one type of K(+) channel carrying the I(sc). This hypothesis was supported by power spectra obtained with a serosa-to-mucosa K(+) gradient, which could be fitted to two Lorentzian components. At present, the K(+) secretory current cannot be localized to taste cells or other cells that might be associated with the secretion of saliva or mucus. Nonetheless, the resulting increase in [K(+)] in fluid bathing the mucosal surface of the tongue could presumably affect the sensitivity of the taste cells. These results contrast with those from the mammalian tongue, in which a mucosa-negative I(sc) results from amiloride-sensitive Na(+) transport. PMID:12077171

  8. Ionoregulatory changes during metamorphosis and salinity exposure of juvenile sea lamprey (Petromyzon marinus L.).

    PubMed

    Reis-Santos, Patrick; McCormick, Stephen D; Wilson, Jonathan M

    2008-03-01

    Ammocoetes of the anadromous sea lamprey Petromyzon marinus L. spend many years in freshwater before metamorphosing and migrating to sea. Metamorphosis involves the radical transformation from a substrate-dwelling, filter feeder into a free-swimming, parasitic feeder. In the present work we examined osmoregulatory differences between ammocoetes and transformers (metamorphic juveniles), and the effects of salinity acclimation. We measured the expression of key ion-transporting proteins [Na(+)/K(+)-ATPase, vacuolar (V)-type H(+)-ATPase and carbonic anhydrase (CA)] as well as a number of relevant blood parameters (hematocrit, [Na(+)] and [Cl(-)]). In addition, immunofluorescence microscopy was used to identify and characterize the distributions of Na(+)/K(+)-ATPase, V-type H(+)-ATPase and CA immunoreactive cells in the gill. Ammocoetes did not survive in the experiments with salinities greater than 10 per thousand, whereas survival in high salinity (> or =25-35 per thousand) increased with increased degree of metamorphosis in transformers. Plasma [Na(+)] and [Cl(-)] of ammocoetes in freshwater was lower than transformers and increased markedly at 10 per thousand. In transformers, plasma ions increased only at high salinity (>25 per thousand). Branchial Na(+)/K(+)-ATPase levels were approximately tenfold higher in transformers compared to ammocoetes and salinity did not affect expression in either group. However, branchial H(+)-ATPase expression showed a negative correlation with salinity in both groups. Na(+)/K(+)-ATPase immunoreactivity was strongest in transformers and associated with clusters of cells in the interlamellar spaces. H(+)-ATPase (B subunit) immunoreactivity was localized to epithelial cells not expressing high Na(+)/K(+)-ATPase immunoreactivity and having a similar tissue distribution as carbonic anhydrase. The results indicate that branchial Na(+)/K(+)-ATPase and salinity tolerance increase in metamorphosing lampreys, and that branchial H(+)-ATPase is

  9. Nitropelagi marinus gen. nov., sp. nov., Isolated From Seawater, Je-bu island, South Korea.

    PubMed

    Jeong, Sun Hwan; Lee, Sang Seob

    2016-09-01

    A Gram-stain-negative, non-spore forming, non-motile and aerobic strain, designated JB22(T), was isolated from seawater, Je-bu Island, South Korea. Strain JB22(T) was catalase and oxidase positive. Optimal growth of JB22(T) was observed at 30 °C and pH 7.0. NaCl tolerance range was 1-9 % (w/v) with an optimum of 2.0 % concentration. The phylogenetic analysis based on 16S rRNA gene sequence of strain JB22(T) showed the highest sequence similarity to those of Pelagicola litorisediminis D1-W8(T) (95.8 %), Roseovarius litoreus GSW-M15(T) (95.2 %), Roseovarius aestuarii SMK-122(T) (95.0 %), Donghicola eburmeus SW-277(T) (95.0 %), and Roseovarius halotolerans HJ50(T) (94.9 %). It contained ubiquine-10 as the major respiratory quinone and C18:1 ω7c (69.3 %), :0 (9.9 %), C18:1 ω7c 11-methyl (9.6 %) as the major fatty acid. The polar lipid profile included phosphatidylcholine, phosphatidylglycerol, and unidentified aminolipid. The DNA G+C content of the strain JB22(T) was 47 mol  %. Based on physiological and chemotaxonomic characteristics, strain JB22(T) should be regarded as a new genus of the family Rhodobacteraceae, for which the Nitropelagi marinus gen. nov., sp. nov. is proposed. The type strain is JB22(T) (= KEMB 3001-101(T) = JCM 30822(T)). PMID:27246498

  10. The natural resistance-associated macrophage protein from the protozoan parasite Perkinsus marinus mediates iron uptake.

    PubMed

    Lin, Zhuoer; Fernández-Robledo, José-Antonio; Cellier, Mathieu F M; Vasta, Gerardo R

    2011-07-26

    Microbial pathogens succeed in acquiring essential metals such as iron and manganese despite their limited availability because of the host's immune response. The eukaryotic natural resistance-associated macrophage proteins mediate uptake of divalent metals and, during infection, may compete directly for metal acquisition with the pathogens' transporters. In this study, we characterize the Nramp gene family of Perkinsus marinus, an intracellular parasite of the eastern oyster, and through yeast complementation, we demonstrate for the first time for a protozoan parasite that Nramp imports environmental Fe. Three PmNramp isogenes differ in their exon-intron structures and encode transcripts that display a trans splicing leader at the 5' end. The protein sequences share conserved properties predicted for the Nramp/Solute carrier 11 (Slc11) family, such as 12-transmembrane segment (TMS) topology (N- and C-termini cytoplasmic) and preferential conservation of four TMS predicted to form a pseudosymmetric proton/metal symport pathway. Yeast fet3fet4 mutant complementation assays showed iron transport activity for PmNramp1 and a fusion chimera of the PmNramp3 hydrophobic core and PmNramp1 N- and C-termini. PmNramp1 site-directed mutagenesis demonstrated that Slc11 invariant and predicted pseudosymmetric motifs (TMS1 Asp-Pro-Gly and TMS6 Met-Pro-His) are key for transport function. PmNramp1 TMS1 mutants D76E, G78A, and D76E/G78A prevented membrane protein expression, while TMS6 M250A, H252Y, and M250A/H252Y specifically abrogated Fe uptake; the TMS6 H252Y mutation also correlates with divergence from Nramp specificity for divalent metals. PMID:21661746

  11. Ionoregulatory changes during metamorphosis and salinity exposure of juvenile sea lamprey (Petromyzon marinus L.)

    USGS Publications Warehouse

    Reis-Santos, P.; McCormick, S.D.; Wilson, J.M.

    2008-01-01

    Ammocoetes of the anadromous sea lamprey Petromyzon marinus L. spend many years in freshwater before metamorphosing and migrating to sea. Metamorphosis involves the radical transformation from a substrate-dwelling, filter feeder into a free-swimming, parasitic feeder. In the present work we examined osmoregulatory differences between ammocoetes and transformers (metamorphic juveniles), and the effects of salinity acclimation. We measured the expression of key ion-transporting proteins [Na+/K+-ATPase, vacuolar (V)-type H+-ATPase and carbonic anhydrase (CA)] as well as a number of relevant blood parameters (hematocrit, [Na+] and [Cl -]). In addition, immunofluorescence microscopy was used to identify and characterize the distributions of Na+/K+-ATPase, V-type H+-ATPase and CA immunoreactive cells in the gill. Ammocoetes did not survive in the experiments with salinities greater than 10???, whereas survival in high salinity (???25-35???) increased with increased degree of metamorphosis in transformers. Plasma [Na+] and [Cl -] of ammocoetes in freshwater was lower than transformers and increased markedly at 10???. In transformers, plasma ions increased only at high salinity (>25???). Branchial Na+/K+-ATPase levels were ??? tenfold higher in transformers compared to ammocoetes and salinity did not affect expression in either group. However, branchial H +-ATPase expression showed a negative correlation with salinity in both groups. Na+/K+-ATPase immunoreactivity was strongest in transformers and associated with clusters of cells in the interlamellar spaces. H+-ATPase (B subunit) immunoreactivity was localized to epithelial cells not expressing high Na+/K+-ATPase immunoreactivity and having a similar tissue distribution as carbonic anhydrase. The results indicate that branchial Na+/K+-ATPase and salinity tolerance increase in metamorphosing lampreys, and that branchial H+-ATPase is downregulated by salinity.

  12. Serum and hepatic vitamin A levels in captive and wild marine toads (Bufo marinus).

    PubMed

    Berkvens, Charlene N; Lentini, Andrew; Dutton, Christopher J; Pearl, David L; Barker, Ian K; Crawshaw, Graham J

    2014-01-01

    The captive breeding program for the endangered Puerto Rican crested toad (Peltophryne [Bufo] lemur) has been hampered by an undiagnosed condition called "Brown Skin Disease" (BSD). Toads develop widespread skin darkening, skin thickening and abnormal shedding and eventually succumb to a chronic loss of viability. This project evaluated the marine toad (Bufo marinus) as a model for the PRCT, examining vitamin A deficiency as a potential cause of BSD. Wild caught marine toads had significantly higher liver vitamin A concentrations (61.89 ± 63.49 µg/g) than captive born marine toads (0.58 ± 0.59 µg/g); P<0.001). A significant difference in serum vitamin A concentration was found between the captive and wild caught toads (P=0.013) and between the low vitamin A-fed and wild caught toads (P=0.004), when controlling for liver vitamin A concentrations. After captive toads were treated with topical and/or oral vitamin A, their hepatic vitamin A concentrations were similar to those of the wild toads, averaging 48.41 ± 37.03 µg/g. However, plasma vitamin A concentrations pre- and post-vitamin A supplementation did not differ statistically. We concluded that plasma vitamin A concentrations do not provide a linear indication of liver/body vitamin A status, and that both topical and oral supplementation with an oil-based vitamin A formulation can increase liver stores in amphibians. No evidence of BSD or other signs of deficiency were noted in the marine toads, although this feeding trial was relatively short (127 days). To date, clinical, pathological and research findings do not support vitamin A deficiency as a primary factor underlying BSD. PMID:25230391

  13. An extremely thermostable amylopullulanase from Staphylothermus marinus displays both pullulan- and cyclodextrin-degrading activities.

    PubMed

    Li, Xiaolei; Li, Dan; Park, Kwan-Hwa

    2013-06-01

    A gene encoding an amylopullulanase of the glycosyl hydrolase (GH) family 57 from Staphylothermus marinus (SMApu) was heterologously expressed in Escherichia coli. SMApu consisted of 639 amino acids with a molecular mass of 75.3 kDa. It only showed maximal amino acid identity of 17.1 % with that of Pyrococcus furiosus amylopullulanase in all identified amylases. Not like previously reported amylopullulanases, SMApu has no signal peptide but contains a continuous GH57N_Apu domain. It had the highest catalytic efficiency toward pullulan (k cat/K m , 342.34 s(-1) mL mg(-1)) and was extremely thermostable with maximal pullulan-degrading activity (42.1 U/mg) at 105 °C and pH 5.0 and a half-life of 50 min at 100 °C. Its activity increased to 116 % in the presence of 5 mM CaCl2. SMApu could also degrade cyclodextrins, which are resistant to the other amylopullulanases. The initial hydrolytic products from pullulan, γ-CD, and 6-O-maltooligosyl-β-CD were [6)-α-D-Glcp-(1 → 4)-α-D-Glcp-(1 → 4)-α-D-Glcp-(1→]n, maltooctaose, and single maltooligosaccharide plus β-CD, respectively. The final hydrolytic products from above-mentioned substrates were maltose and glucose. These results confirm that SMApu is a novel amylopullulanase of the family GH57 possessing the cyclodextrin-degrading activity of cyclomaltodextrinase. PMID:23001056

  14. Associations between land use and Perkinsus marinus infection of eastern oysters in a high salinity, partially urbanized estuary

    USGS Publications Warehouse

    Gray, Brian R.; Bushek, David; Drane, J. Wanzer; Porter, Dwayne

    2009-01-01

    Infection levels of eastern oysters by the unicellular pathogen Perkinsus marinus have been associated with anthropogenic influences in laboratory studies. However, these relationships have been difficult to investigate in the field because anthropogenic inputs are often associated with natural influences such as freshwater inflow, which can also affect infection levels. We addressed P. marinus-land use associations using field-collected data from Murrells Inlet, South Carolina, USA, a developed, coastal estuary with relatively minor freshwater inputs. Ten oysters from each of 30 reefs were sampled quarterly in each of 2 years. Distances to nearest urbanized land class and to nearest stormwater outfall were measured via both tidal creeks and an elaboration of Euclidean distance. As the forms of any associations between oyster infection and distance to urbanization were unknown a priori, we used data from the first and second years of the study as exploratory and confirmatory datasets, respectively. With one exception, quarterly land use associations identified using the exploratory dataset were not confirmed using the confirmatory dataset. The exception was an association between the prevalence of moderate to high infection levels in winter and decreasing distance to nearest urban land use. Given that the study design appeared adequate to detect effects inferred from the exploratory dataset, these results suggest that effects of land use gradients were largely insubstantial or were ephemeral with duration less than 3 months.

  15. The combined influence of sub-optimal temperature and salinity on the in vitro viability of Perkinsus marinus, a protistan parasite of the eastern oyster Crassostrea virginica

    USGS Publications Warehouse

    La Peyre, M.K.; Casas, S.M.; Gayle, W.; La Peyre, Jerome F.

    2010-01-01

    Perkinsus marinus is a major cause of mortality in eastern oysters along the Gulf of Mexico and Atlantic coasts. It is also well documented that temperature and salinity are the primary environmental factors affecting P. marinus viability and proliferation. However, little is known about the effects of combined sub-optimal temperatures and salinities on P. marinus viability. This in vitro study examined those effects by acclimating P. marinus at three salinities (7, 15, 25. ppt) to 10 ??C to represent the lowest temperatures generally reached in the Gulf of Mexico, and to 2 ??C to represent the lowest temperatures reached along the mid-Atlantic coasts and by measuring changes in cell viability and density on days 1, 30, 60 and 90 following acclimation. Cell viability and density were also measured in 7. ppt cultures acclimated to each temperature and then transferred to 3.5. ppt. The largest decreases in cell viability occurred only with combined low temperature and salinity, indicating that there is clearly a synergistic effect. The largest decreases in cell viability occurred only with both low temperature and salinity after 30. days (3.5. ppt, 2 ??C: 0% viability), 60. days (3.5. ppt, 10 ??C: 0% viability) and 90. days (7. ppt, 2 ??C: 0.6 ?? 0.7%; 7. ppt, 10 ??C: 0.2 ?? 0.2%). ?? 2010 .

  16. The combined influence of sub-optimal temperature and salinity on the in vitro viability of Perkinsus marinus, a protistan parasite of the eastern oyster Crassostrea virginica.

    PubMed

    La Peyre, Megan K; Casas, Sandra M; Gayle, Whitney; La Peyre, Jerome F

    2010-10-01

    Perkinsus marinus is a major cause of mortality in eastern oysters along the Gulf of Mexico and Atlantic coasts. It is also well documented that temperature and salinity are the primary environmental factors affecting P. marinus viability and proliferation. However, little is known about the effects of combined sub-optimal temperatures and salinities on P. marinus viability. This in vitro study examined those effects by acclimating P. marinus at three salinities (7, 15, 25 ppt) to 10 degrees C to represent the lowest temperatures generally reached in the Gulf of Mexico, and to 2 degrees C to represent the lowest temperatures reached along the mid-Atlantic coasts and by measuring changes in cell viability and density on days 1, 30, 60 and 90 following acclimation. Cell viability and density were also measured in 7 ppt cultures acclimated to each temperature and then transferred to 3.5 ppt. The largest decreases in cell viability occurred only with combined low temperature and salinity, indicating that there is clearly a synergistic effect. The largest decreases in cell viability occurred only with both low temperature and salinity after 30 days (3.5 ppt, 2 degrees C: 0% viability), 60 days (3.5 ppt, 10 degrees C: 0% viability) and 90 days (7 ppt, 2 degrees C: 0.6+/-0.7%; 7 ppt, 10 degrees C: 0.2+/-0.2%). PMID:20600094

  17. Ionic mechanism for the photoreceptor potential of the retina of Bufo marinus

    PubMed Central

    Brown, J. E.; Pinto, L. H.

    1974-01-01

    1. Membrane potentials were recorded from single rods in the isolated retina of Bufo marinus while the ionic composition of the extracellular medium was rapidly changed. Substitution of 2 mM aspartate- for Cl- produced a prompt depolarization of horizontal cells, but no modification of either resting potential or response to light in receptor cells. This implies that feed-back from horizontal cells to receptor cells was not active. 2. During substitution of choline+ or Li+ for Na+, and during isosmotic substitution of sucrose for NaCl, the resting potential of receptor cells became more negative and responses to light were abolished. During exposure to K+-free medium, the resting potential became slightly more negative and the responses to light became larger and developed small after-depolarizations. Exposure to [K+]out of four times normal resulted in permanent diminution of response magnitude and permanent change of response waveshape. Removal of Mg2+, four times normal [Mg2+]out or substitution of methylsulphate- for Cl- had no effect on resting potential or responses to light. With the exception of the small effects seen with altered [K+]out these results are consistent with the receptor potential being generated by a light-induced decrease of membrane conductance to Na+. 3. Exposure to decreased [Ca2+]out caused both a depolarization of the receptor membrane in the dark and an increase in the magnitude of the maximal response that could be evoked by a test stimulus. The magnitude of the increase in response equalled the magnitude of the depolarization. Exposure to increased [Ca2+]out or steady background light caused both a steady hyperpolarization and a decrease in the magnitude of the maximal response that could be evoked by a test stimulus. For steady hyperpolarizations greater than 3·5 mV, whether caused by elevated [Ca2+]out or steady background light, the decrease in response magnitude exceeded the magnitude of the hyperpolarization. These results

  18. Prostaglandins as mediators of acidification in the urinary bladder of Bufo marinus

    SciTech Connect

    Frazier, L.W.; Yorio, T. )

    1990-05-01

    Experiments were performed to determine whether prostaglandins (PG) play a role in H+ and NH4+ excretion in the urinary bladder of Bufo marinus. Ten paired hemibladders from normal toads were mounted in chambers. One was control and the other hemibladder received PGE2 in the serosal medium (10(-5) M). H+ excretion was measured by change in pH in the mucosal fluid and reported in units of nmol (100 mg tissue)-1 (min)-1. NH4+ excretion was measured colorimetrically and reported in the same units. The control group H+ excretion was 8.4 +/- 1.67, while the experimental group was 16.3 +/- 2.64 (P less than 0.01). The NH4+ excretion in the experimental and control group was not significantly different. Bladders from toads in a 48-hr NH4+Cl acidosis (metabolic) did not demonstrate this response to PGE2 (P greater than 0.30). Toads were put in metabolic acidosis by gavaging with 10 ml of 120 mM NH4+Cl 3 x day for 2 days. In another experiment, we measured levels of PG in bladders from control (N) and animals placed in metabolic acidosis (MA). Bladders were removed from the respective toad, homogenized, extracted, and PG separated using high-pressure liquid chromatography and quantified against PG standards. The results are reported in ng (mg tissue)-1. PGE2 fraction in N was 1.09 +/- 0.14 and in MA was 3.21 +/- 0.63 (P less than 0.01). PGF1 alpha, F2 alpha and I2 were not significantly different in N and MA toads. Bladders were also removed from N and MA toads, and incubated in Ringer's solution containing (3H)arachidonic acid (0.2 microCi/ml) at 25 degrees C for 2 hr. Bladders were then extracted for PG and the extracts separated by thin layer chromatography. PG were identified using standards and autoradiography, scraped from plates, and counted in a scintillation detector. The results are reported in cpm/mg tissue x hr +/- SEM.

  19. Effects of salinity on upstream-migrating, spawning sea lamprey, Petromyzon marinus

    PubMed Central

    Ferreira-Martins, D.; Coimbra, J.; Antunes, C.; Wilson, J. M.

    2016-01-01

    The sea lamprey, Petromyzon marinus, is an anadromous, semelparous species that is vulnerable to endangered in parts of its native range due in part to loss of spawning habitat because of man-made barriers. The ability of lampreys to return to the ocean or estuary and search out alternative spawning river systems would be limited by their osmoregulatory ability in seawater. A reduction in tolerance to salinity has been documented in migrants, although the underlying mechanisms have not been characterized. We examined the capacity for marine osmoregulation in upstream spawning migrants by characterizing the physiological effects of salinity challenge from a molecular perspective. Estuarine-captured migrants held in freshwater (FW) for ∼1 week (short-term acclimation) or 2 months (long-term acclimation) underwent an incremental salinity challenge until loss of equilibrium occurred and upper thresholds of 25 and 17.5, respectively, occurred. Regardless of salinity tolerance, all lamprey downregulated FW ion-uptake mechanisms [gill transcripts of Na+:Cl− cotransporter (NCC/slc12a3) and epithelial Na+ channel (ENaC/scnn1) and kidney Na+/K+-ATPase (NKA) protein and activity but not transcript]. At their respective salinity limits, lamprey displayed a clear osmoregulatory failure and were unable to regulate [Na+] and [Cl−] in plasma and intestinal fluid within physiological limits, becoming osmocompromised. A >90% drop in haematocrit indicated haemolysis, and higher plasma concentrations of the cytosolic enzymes alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase indicated damage to other tissues, including liver. However, >80% of short-term FW-acclimated fish were able to osmoregulate efficiently, with less haemolysis and tissue damage. This osmoregulatory ability was correlated with significant upregulation of the secretory form of Na+:K+:2Cl− cotransporter (NKCC1/slc12a2) transcript levels and the re-emergence of seawater

  20. Effects of salinity on upstream-migrating, spawning sea lamprey, Petromyzon marinus.

    PubMed

    Ferreira-Martins, D; Coimbra, J; Antunes, C; Wilson, J M

    2016-01-01

    The sea lamprey, Petromyzon marinus, is an anadromous, semelparous species that is vulnerable to endangered in parts of its native range due in part to loss of spawning habitat because of man-made barriers. The ability of lampreys to return to the ocean or estuary and search out alternative spawning river systems would be limited by their osmoregulatory ability in seawater. A reduction in tolerance to salinity has been documented in migrants, although the underlying mechanisms have not been characterized. We examined the capacity for marine osmoregulation in upstream spawning migrants by characterizing the physiological effects of salinity challenge from a molecular perspective. Estuarine-captured migrants held in freshwater (FW) for ∼1 week (short-term acclimation) or 2 months (long-term acclimation) underwent an incremental salinity challenge until loss of equilibrium occurred and upper thresholds of 25 and 17.5, respectively, occurred. Regardless of salinity tolerance, all lamprey downregulated FW ion-uptake mechanisms [gill transcripts of Na(+):Cl(-) cotransporter (NCC/slc12a3) and epithelial Na(+) channel (ENaC/scnn1) and kidney Na(+)/K(+)-ATPase (NKA) protein and activity but not transcript]. At their respective salinity limits, lamprey displayed a clear osmoregulatory failure and were unable to regulate [Na(+)] and [Cl(-)] in plasma and intestinal fluid within physiological limits, becoming osmocompromised. A >90% drop in haematocrit indicated haemolysis, and higher plasma concentrations of the cytosolic enzymes alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase indicated damage to other tissues, including liver. However, >80% of short-term FW-acclimated fish were able to osmoregulate efficiently, with less haemolysis and tissue damage. This osmoregulatory ability was correlated with significant upregulation of the secretory form of Na(+):K(+):2Cl(-) cotransporter (NKCC1/slc12a2) transcript levels and the re-emergence of

  1. Effects of sea lamprey (Petromyzon marinus) control in the Great Lakes on aquatic plants, invertebrates and amphibians

    USGS Publications Warehouse

    Gilderhus, P.A.; Johnson, B.G.H.

    1980-01-01

    The chemicals 3-trifluoromethyl-4-nitrophenol (TFM) or a combination of TFM and 2a??,5-dichloro-4a??-nitrosalicylanilide (Bayer 73) have been used to control the sea lamprey (Petromyzon marinus) in the Great Lakes for about 20 yr. These chemicals cause some mortalities of Oligochaeta and Hirudinea, immature forms of Ephemeroptera (Hexagenia sp.), and certain Trichoptera, Simuliidae, and Amphibia (Necturus sp.). The combination of TFM and Bayer 73 may affect some Pelecypoda and Gastropoda, but its overall effects on invertebrates are probably less than those of TFM alone. Granular Bayer 73 is likely to induce mortalities among oligochaetes, microcrustaceans, chironomids, and pelecypods. No evidence exists that the lampricides have caused the catastrophic decline or disappearance of any species. The overall impact of chemical control of sea lampreys on aquatic communities has been minor compared with the benefits derived.

  2. The effect of pinealectomy, continuous light, and continuous darkness on metamorphosis of anadromous sea lampreys, Petromyzon marinus L

    SciTech Connect

    Cole, W.C.; Youson, J.H.

    1981-12-01

    The role of the pineal complex in lamprey metamorphosis was investigated by examining the influence of pinealectomy and continuous light and darkness on the initiation of this event in anadromous sea lampreys, Petromyzon marinus L. Larval lampreys, which on the basis of a condition factor were considered likely to enter metamorphosis in July, were separated in May of 1979 and 1980 into the following groups: (1) intact controls, (2) sham-operated controls, (3) pinealectomized individuals, (4) those exposed to continuous light, and (5) those exposed to continuous light or dark. The importance of the pineal complex to metamorphosis was supported by morphological evidence that, in all presumably pinealectomized individuals that entered metamorphosis, the complex had apparently not been removed during the surgical procedure. The ways in which the pineal complex may be involved in lamprey metamorphosis are discussed.

  3. Subcellular localization of the magnetosome protein MamC in the marine magnetotactic bacterium Magnetococcus marinus strain MC-1 using immunoelectron microscopy

    SciTech Connect

    Valverde-Tercedor, C; Abada-Molina, F; Martinez-Bueno, M; Pineda-Molina, Estela; Chen, Lijun; Oestreicher, Zachery; Lower, Brian H; Lower, Steven K; Bazylinski, Dennis A; Jimenez-Lopez, C

    2014-04-24

    Magnetotactic bacteria are a diverse group of prokaryotes that biomineralize intracellular magnetosomes, composed of magnetic (Fe3O4) crystals each enveloped by a lipid bilayer membrane that contains proteins not found in other parts of the cell. Although partial roles of some of these magnetosome proteins have been determined, the roles of most have not been completely elucidated, particularly in how they regulate the biomineralization process. While studies on the localization of these proteins have been focused solely on Magnetospirillum species, the goal of the present study was to determine, for the first time, the localization of the most abundant putative magnetosome membrane protein, MamC, in Magnetococcus marinus strain MC-1. MamC was expressed in Escherichia coli and purified. Monoclonal antibodies were produced against MamC and immunogold labeling TEM was used to localize MamC in thin sections of cells of M. marinus. Results show that MamC is located only in the magnetosome membrane of Mc. marinus. Based on our findings and the abundance of this protein, it seems likely that it is important in magnetosome biomineralization and might be used in controlling the characteristics of synthetic nanomagnetite.

  4. Real-time PCR investigation of parasite ecology: in situ determination of oyster parasite Perkinsus marinus transmission dynamics in lower Chesapeake Bay.

    PubMed

    Audemard, C; Ragone Calvo, L M; Paynter, K T; Reece, K S; Burreson, E M

    2006-06-01

    Perkinsus marinus is a severe pathogen of the oyster Crassostrea virginica on the East Coast of the United States. Transmission dynamics of this parasite were investigated in situ for 2 consecutive years (May through October) at 2 lower Chesapeake Bay sites. Compared to previous studies where seasonal infection patterns in oysters were measured, this study also provided parasite water column abundance data measured using real-time PCR. As previously observed, salinity and temperature modulated parasite transmission dynamics. Using regression analysis, parasite prevalence, oyster mortalities and parasite water column abundance were significantly positively related to salinity. Perkinsus marinus weighted prevalence in wild oysters and parasite water column abundance both were significantly related to temperature, but the responses lagged 1 month behind temperature. Parasite water column abundance was the highest during August (up to 1,200 cells/l) and was significantly related to P. marinus weighted prevalence in wild oysters, and to wild oyster mortality suggesting that parasites are released in the environment via both moribund and live hosts (i.e. through feces). Incidence was not significantly related to parasite water column abundance, which seems to indicate the absence of a linear relationship or that infection acquisition is controlled by a more complex set of parameters. PMID:16476183

  5. Cribrihabitans marinus gen. nov., sp. nov., isolated from a biological filter in a marine recirculating aquaculture system.

    PubMed

    Chen, Zhu; Liu, Ying; Liu, Liang-Zi; Zhong, Zhi-Ping; Liu, Zhi-Pei; Liu, Ying

    2014-04-01

    A Gram-negative bacterium, strain CZ-AM5(T), was isolated from an aerated biological filter in a marine recirculating aquaculture system in Tianjin, China. Its taxonomic position was investigated by using a polyphasic approach. Cells of strain CZ-AM5(T) were non-spore-forming rods, 0.5-0.8 µm wide and 1.2-2.0 µm long, and motile by means of one or two polar or lateral flagella. Strain CZ-AM5(T) was strictly aerobic, heterotrophic, oxidase-negative and catalase-positive. Growth occurred at 15-40 °C (optimum, 30-35 °C), at pH 6.5-10.5 (optimum, pH 7.0-7.5) and in the presence of 0-12.0 % (w/v) NaCl (optimum, 4.0 %). The predominant fatty acid was C18 : 1ω7c (80.3 %). Ubiquinone 10 (Q-10) was the sole respiratory quinone. The polar lipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, an unknown aminolipid, an unknown phospholipid and three unknown lipids. The DNA G+C content was 60.4 mol%. Strain CZ-AM5(T) showed the highest 16S rRNA gene sequence similarity (96.5 %) to Phaeobacter caeruleus LMG 24369(T); it exhibited 16S rRNA gene sequence similarity of 95.0-96.5, 95.2-96.3, 96.2, 94.6-95.7 and 94.8-95.8 % to members of the genera Phaeobacter, Ruegeria, Citreimonas, Leisingera and Donghicola, respectively. However, phylogenetic trees based on 16S rRNA gene sequences showed that strain CZ-AM5(T) did not join any of the above genera, but formed a distinct lineage in the trees. On the basis of phenotypic, chemotaxonomic and phylogenetic analyses, strain CZ-AM5(T) is considered to represent a novel genus and species of the family Rhodobacteraceae, for which the name Cribrihabitans marinus gen. nov., sp. nov. is proposed. The type strain of Cribrihabitans marinus is CZ-AM5(T) ( = CGMCC 1.13219(T) = JCM 19401(T)). PMID:24425741

  6. Metabolism of the /sup 18/O-methoxy substituent of 3-methoxybenzoic acid and other unlabeled methoxybenzoic acids by anaerobic bacteria. [Eubacterium limosum; Acetobacterium woodil; Syntrophococcus; Clostridium; Desulfotomaculum; Enterobacter

    SciTech Connect

    DeWeerd, J.A.; Saxena, A.; Nagle, D.P. Jr.; Sulflita, J.M.

    1988-05-01

    The mechanism of the bioconversion of methoxylated benzoic acids to the hydroxylated derivatives was investigated with a model substrate and cultures of one anaerobic consortium, eight strict anaerobic bacteria, and one facultative anaerobic microorganism. We found that a haloaromatic dehalogenating consortium, a dehalogenating isolate from that consortium, Eubacterium, limosum, and a strain of Acetobacterium woodii metabolized 3-(methoxy-/sup 18/O)methoxybenzoic acid (3-anisic acid) to 3-(hydroxy-/sup 18/O)hydroxybenzoic acid stoichiometrically at rates of 1.5, 3.2, 52.4, and 36.7 nmol/min per mg of protein, respectively. A different strain of Acetobacterium and strains of Syntrophococcus, Clostridium Desulfotomaculum, Enterobacter, and an anaerobic bacterium, strain TH-001, were unable to transform this compound. The O-demethylating ability of E. limosum was induced only with appropriate methoxylated benzoates but not with D-glucose, lactate, isoleucine, or methanol. Cross-acclimation and growth experiments with E. limosum showed a rate of metabolism that was an order of magnitude slower and showed no growth with either 4-methoxysalicylic acid (2-hydroxy-4-methoxybenzoic acid) or 4-anisic acid (4-methoxybenzoic acid) when adapted to 3-anisic acid. However, A. woodii NZva-16 showed slower rates and no growth with 3- or 4-methoxysalicylic acid when adapted to 3-anisic acid in similar experiments.

  7. New estimates of lethality of sea lamprey (Petromyzon marinus) attacks on lake trout (Salvelinus namaycush): Implications for fisheries management

    USGS Publications Warehouse

    Madenjian, C.P.; Chipman, B.D.; Marsden, J.E.

    2008-01-01

    Sea lamprey (Petromyzon marinus) control in North America costs millions of dollars each year, and control measures are guided by assessment of lamprey-induced damage to fisheries. The favored prey of sea lamprey in freshwater ecosystems has been lake trout (Salvelinus namaycush). A key parameter in assessing sea lamprey damage, as well as managing lake trout fisheries, is the probability of an adult lake trout surviving a lamprey attack. The conventional value for this parameter has been 0.55, based on laboratory experiments. In contrast, based on catch curve analysis, mark-recapture techniques, and observed wounding rates, we estimated that adult lake trout in Lake Champlain have a 0.74 probability of surviving a lamprey attack. Although sea lamprey growth in Lake Champlain was lower than that observed in Lake Huron, application of an individual-based model to both lakes indicated that the probability of surviving an attack in Lake Champlain was only 1.1 times higher than that in Lake Huron. Thus, we estimated that lake trout survive a lamprey attack in Lake Huron with a probability of 0.66. Therefore, our results suggested that lethality of a sea lamprey attack on lake trout has been overestimated in previous model applications used in fisheries management. ?? 2008 NRC.

  8. Behavioural response of adult sea lamprey (Petromyzon marinus) to predator and conspecific alarm cues: evidence of additive effects

    USGS Publications Warehouse

    Di Rocco, Richard T; Imre, Istvan; Johnson, Nicholas; Brown, Grant B

    2015-01-01

    Sea lampreys Petromyzon marinus, an invasive pest in the Upper Great Lakes, avoid odours that represent danger in their habitat. These odours include conspecific alarm cues and predator cues, like 2-phenylethylamine hydrochloride (PEA HCl), which is found in the urine of mammalian predators. Whether conspecific alarm cues and predator cues function additively or synergistically when mixed together is unknown. The objectives of this experimental study were to determine if the avoidance response of sea lamprey to PEA HCl is proportional to the concentration delivered, and if the avoidance response to the combination of a predator cue (PEA HCl) and sea lamprey alarm cue is additive. To accomplish the first objective, groups of ten sea lampreys were placed in an artificial stream channel and presented with stepwise concentrations of PEA HCl ranging from 5 × 10−8 to 5 × 10−10 M and a deionized water control. Sea lampreys exhibited an increase in their avoidance behaviour in response to increasing concentrations of PEA HCl. To accomplish the second objective, sea lampreys were exposed to PEA HCl, conspecific alarm cue and a combination of the two. Sea lampreys responded to the combination of predator cue and conspecific alarm cue in an additive manner.

  9. Direct behavioral evidence that unique bile acids released by larval sea lamprey (Petromyzon marinus) function as a migratory pheromone

    USGS Publications Warehouse

    Bjerselius, R.; Li, W.; Teeter, J.H.; Seelye, J.G.; Johnsen, P.B.; Maniak, P.J.; Grant, G.C.; Polkinghorne, C.N.; Sorensen, P.W.

    2000-01-01

    Four behavioral experiments conducted in both the laboratory and the field provide evidence that adult sea lamprey (Petromyzon marinus) select spawning rivers based on the odor of larvae that they contain and that bile acids released by the larvae are part of this pheromonal odor. First, when tested in a recirculating maze, migratory adult lamprey spent more time in water scented with larvae. However, when fully mature, adults lost their responsiveness to larvae and preferred instead the odor of mature individuals. Second, when tested in a flowing stream, migratory adults swam upstream more actively when the water was scented with larvae. Third, when migratory adults were tested in a laboratory maze containing still water, they exhibited enhanced swimming activity in the presence of a 0.1 nM concentration of the two unique bile acids released by larvae and detected by adult lamprey. Fourth, when adults were exposed to this bile acid mixture within flowing waters, they actively swam into it. Taken together, these data suggest that adult lamprey use a bile acid based larval pheromone to help them locate spawning rivers and that responsiveness to this cue is influenced by current flow, maturity, and time of day. Although the precise identity and function of the larval pheromone remain to be fully elucidated, we believe that this cue will ultimately prove useful as an attractant in sea lamprey control.

  10. Complete sequence of a sea lamprey (Petromyzon marinus) mitochondrial genome: Early establishment of the vertebrate genome organization

    SciTech Connect

    Lee, W.J.; Kocher, T.D.

    1995-02-01

    The complete nucleotide sequence of a sea lamprey (Petromyzon marinus) mitochondrial genome has been determined. The lamprey genome is 16,201 bp in length and contains genes for 13 proteins, two rRNAs, 22 tRNAs and two major noncoding regions. The order and transcriptional polarities of protein-coding genes are basically identical to those of other chordate mtDNAs, demonstrating that the common mitochondrial gene organization of vertebrates was established at early stage of vertebrate evolution. The two major noncoding regions are separated by two tRNA genes. The first region probably functions as the control region because it contains distinctive conserved sequence blocks (CSB-II and III) common to other vertebrate control regions. The central conserved domain observed in other vertebrate control regions is not found in the lamprey, suggesting that it is a recently evolved functional domain in vertebrates. Noncoding segments are not found in the expected position of the origin of replication for the second strand, suggesting either that one of the tRNA genes has a dual function or that the second noncoding region may function as the second-strand origin. The base composition at the wobble positions of fourfold degenerate codon families is highly biased toward thymine (32.7%). Values of GC- and AT-skew are typical of vertebrate mitochondrial genomes. 38 refs., 11 figs., 5 tabs.

  11. Application of a putative alarm cue hastens the arrival of invasive sea lamprey (Petromyzon marinus) at a trapping location

    USGS Publications Warehouse

    Hume, John B; Meckley, Trevor D.; Johnson, Nicholas; Luhring, Thomas M; Siefkes, Michael J; Wagner, C. Michael

    2015-01-01

    The sea lamprey Petromyzon marinus is an invasive pest in the Laurentian Great Lakes basin, threatening the persistence of important commercial and recreational fisheries. There is substantial interest in developing effective trapping practices via the application of behavior-modifying semiochemicals (odors). Here we report on the effectiveness of utilizing repellent and attractant odors in a push–pull configuration, commonly employed to tackle invertebrate pests, to improve trapping efficacy at permanent barriers to sea lamprey migration. When a half-stream channel was activated by a naturally derived repellent odor (a putative alarm cue), we found that sea lamprey located a trap entrance significantly faster than when no odor was present as a result of their redistribution within the stream. The presence of a partial sex pheromone, acting as an attractant within the trap, was not found to further decrease the time to when sea lamprey located a trap entrance relative to when the alarm cue alone was applied. Neither the application of alarm cue singly nor alarm cue and partial sex pheromone in combination was found to improve the numbers of sea lamprey captured in the trap versus when no odor was present — likely because nominal capture rate during control trials was unusually high during the study period. Behavioural guidance using these odors has the potential to both improve control of invasive non-native sea lamprey in the Great Lakes as well as improving the efficiency of fish passage devices used in the restoration of threatened lamprey species elsewhere.

  12. Structural Mechanism for Light-driven Transport by a New Type of Chloride Ion Pump, Nonlabens marinus Rhodopsin-3.

    PubMed

    Hosaka, Toshiaki; Yoshizawa, Susumu; Nakajima, Yu; Ohsawa, Noboru; Hato, Masakatsu; DeLong, Edward F; Kogure, Kazuhiro; Yokoyama, Shigeyuki; Kimura-Someya, Tomomi; Iwasaki, Wataru; Shirouzu, Mikako

    2016-08-19

    The light-driven inward chloride ion-pumping rhodopsin Nonlabens marinus rhodopsin-3 (NM-R3), from a marine flavobacterium, belongs to a phylogenetic lineage distinct from the halorhodopsins known as archaeal inward chloride ion-pumping rhodopsins. NM-R3 and halorhodopsin have distinct motif sequences that are important for chloride ion binding and transport. In this study, we present the crystal structure of a new type of light-driven chloride ion pump, NM-R3, at 1.58 Å resolution. The structure revealed the chloride ion translocation pathway and showed that a single chloride ion resides near the Schiff base. The overall structure, chloride ion-binding site, and translocation pathway of NM-R3 are different from those of halorhodopsin. Unexpectedly, this NM-R3 structure is similar to the crystal structure of the light-driven outward sodium ion pump, Krokinobacter eikastus rhodopsin 2. Structural and mutational analyses of NM-R3 revealed that most of the important amino acid residues for chloride ion pumping exist in the ion influx region, located on the extracellular side of NM-R3. In contrast, on the opposite side, the cytoplasmic regions of K. eikastus rhodopsin 2 were reportedly important for sodium ion pumping. These results provide new insight into ion selection mechanisms in ion pumping rhodopsins, in which the ion influx regions of both the inward and outward pumps are important for their ion selectivities. PMID:27365396

  13. Behavioral responses to immune-system activation in an anuran (the cane toad, Bufo marinus): field and laboratory studies.

    PubMed

    Llewellyn, D; Brown, G P; Thompson, M B; Shine, R

    2011-01-01

    The challenges posed by parasites and pathogens evoke behavioral as well as physiological responses. Such behavioral responses are poorly understood for most ectothermic species, including anuran amphibians. We quantified effects of simulated infection (via injection of bacterial lipopolysaccharide [LPS]) on feeding, activity, and thermoregulation of cane toads Bufo marinus within their invasive range in tropical Australia. LPS injection reduced feeding rates in laboratory trials. For toads in outdoor enclosures, LPS injection reduced activity and shifted body temperature profiles. Although previous research has attributed such thermal shifts to behavioral fever (elevated body temperatures may help fight infection), our laboratory studies suggest instead that LPS-injected toads stopped moving. In a thermal gradient, LPS-injected toads thus stayed close to whichever end of the gradient (hot or cold) they were first introduced; the introduction site (rather than behavioral thermoregulation) thus determined body temperature regimes. Shifts in thermal profiles of LPS-injected toads in outdoor enclosures also were a secondary consequence of inactivity. Thus, the primary behavioral effects of an immune response in cane toads are reduced rates of activity and feeding. Thermoregulatory modifications also occur but only as a secondary consequence of inactivity. PMID:21128787

  14. Body pool and synthesis of ascorbic acid in adult sea lamprey (Petromyzon marinus): An agnathan fish with gulonolactone oxidase activity

    PubMed Central

    Moreau, Régis; Dabrowski, Konrad

    1998-01-01

    Although many vertebrates can synthesize ascorbic acid (vitamin C), it is still unclear from the evolutionary perspective when the ability to synthesize the vitamin first appeared in the animal kingdom and how frequently the trait has been lost. We report here ascorbic acid biosynthesis ability in sea lamprey (Petromyzon marinus) which represent the most ancient vertebrate lineage examined thus far for presence of gulonolactone oxidase, the enzyme catalyzing the terminal step in biosynthesis of vitamin C. This finding supports the view that the ancestors of living vertebrates were not scurvy prone and that the loss of gulonolactone oxidase activity subsequently occurred several times in vertebrate phylogeny. Adult sea lamprey allocate significant amounts of ascorbic acid to the gonads to guaranty high-quality gametes. Tissue stores of ascorbate were maintained by de novo synthesis (1.2–1.3 mg of ascorbic acid/300-g sea lamprey per day at 15°C) while sea lamprey fast during spawning migration. We estimate that the in vivo daily renewal rate of ascorbate is 4–5% of the whole-body ascorbate pool based on measurement of its biosynthesis and concentration in the whole animal. PMID:9707638

  15. Evaluating the growth potential of sea lampreys (Petromyzon marinus) feeding on siscowet lake trout (Salvelinus namaycush) in Lake Superior

    USGS Publications Warehouse

    Moody, E.K.; Weidel, B.C.; Ahrenstorff, T.D.; Mattes, W.P.; Kitchell, J.F.

    2011-01-01

    Differences in the preferred thermal habitat of Lake Superior lake trout morphotypes create alternative growth scenarios for parasitic sea lamprey (Petromyzon marinus) attached to lake trout hosts. Siscowet lake trout (Salvelinus namaycush) inhabit deep, consistently cold water (4–6 °C) and are more abundant than lean lake trout (Salvelinus namaycush) which occupy temperatures between 8 and 12 °C during summer thermal stratification. Using bioenergetics models we contrasted the growth potential of sea lampreys attached to siscowet and lean lake trout to determine how host temperature influences the growth and ultimate size of adult sea lamprey. Sea lampreys simulated under the thermal regime of siscowets are capable of reaching sizes within the range of adult sea lamprey sizes observed in Lake Superior tributaries. High lamprey wounding rates on siscowets suggest siscowets are important lamprey hosts. In addition, siscowets have higher survival rates from lamprey attacks than those observed for lean lake trout which raises the prospect that siscowets serve as a buffer to predation on more commercially desirable hosts such as lean lake trout, and could serve to subsidize lamprey growth.

  16. Tepidicaulis marinus gen. nov., sp. nov., a marine bacterium that reduces nitrate to nitrous oxide under strictly microaerobic conditions.

    PubMed

    Takeuchi, Mio; Yamagishi, Takao; Kamagata, Yoichi; Oshima, Kenshiro; Hattori, Masahira; Katayama, Taiki; Hanada, Satoshi; Tamaki, Hideyuki; Marumo, Katsumi; Maeda, Hiroto; Nedachi, Munetomo; Iwasaki, Wataru; Suwa, Yuichi; Sakata, Susumu

    2015-06-01

    A moderately thermophilic, aerobic, stalked bacterium (strain MA2T) was isolated from marine sediments in Kagoshima Bay, Japan. Phylogenetic analysis of 16S rRNA gene sequences indicated that strain MA2T was most closely related to the genera Rhodobium,Parvibaculum, and Rhodoligotrophos (92-93 % similarity) within the class Alphaproteobacteria. Strain MA2T was a Gram-stain-negative and stalked dimorphic bacteria. The temperature range for growth was 16-48 °C (optimum growth at 42 °C). This strain required yeast extract and NaCl (>1 %, w/v) for growth, tolerated up to 11 % (w/v) NaCl, and was capable of utilizing various carbon sources. The major cellular fatty acid and major respiratory quinone were C18 : 1ω7c and ubiquinone-10, respectively. The DNA G+C content was 60.7 mol%. Strain MA2T performed denitrification and produced N2O from nitrate under strictly microaerobic conditions. Strain MA2T possessed periplasmic nitrate reductase (Nap) genes but not membrane-bound nitrate reductase (Nar) genes. On the basis of this morphological, physiological, biochemical and genetic information a novel genus and species, Tepidicaulis marinus gen. nov., sp. nov., are proposed, with MA2T ( = NBRC 109643T = DSM 27167T) as the type strain of the species. PMID:25740933

  17. Introns, alternative splicing, spliced leader trans-splicing and differential expression of pcna and cyclin in Perkinsus marinus.

    PubMed

    Zhang, Huan; Dungan, Christopher F; Lin, Senjie

    2011-01-01

    To gain understanding on the structure and regulation of growth-related genes of the parasitic alveolatePerkinsus marinus, we analyzed genes encoding proliferating cell nuclear antigen (pcna) and cyclins (cyclin). Comparison of the full-length cDNAs with the corresponding genomic sequences revealedtrans-splicing of the mRNAs of these genes with a conserved 21-22 nt spliced leader. Over 10 copies ofpcnawere detected, with identical gene structures and similar nucleotide (nt) sequences (88-99%), encoding largely identical amino acid sequences (aa). Two distinct types ofcyclin(Pmacyclin1 andPmacyclin2) were identified, with 66-69% nt and 81-85% aa similarities.Pmacyclin2 was organized in tandem repeats, and was alternatively spliced, giving rise to five subtypes of transcripts. For bothpcnaandcyclingenes, 6-10 introns were found. Quantitative RT-PCR assays showed thatpcnaandPmacyclin2 expression levels were low with small variations during a 28-h time course, whereasPmacyclin1 transcript abundance was 10-100 times higher, and increased markedly during active cell division, suggesting that it is a mitoticcyclinand can be a useful growth marker for this species. The gene structure and expression features along with phylogenetic results position this organism between dinoflagellates and apicomplexans, but its definitive affiliation among alveolates requires further studies. PMID:20650682

  18. Effects of air-exposure gradients on spatial infection patterns of Perkinsus marinus in the eastern oyster Crassostrea virginica.

    PubMed

    Malek, Jennafer C; Breitburg, Denise L

    2016-02-25

    Spatial distributions of species can be shaped by factors such as parasites, mortality, and reproduction, all of which may be influenced by differences in physical factors along environmental gradients. In nearshore tidal waters, an elevational gradient in aerial exposure during low tide can shape the spatial distributions of benthic marine organisms. The eastern oyster Crassostrea virginica is an ecologically and economically important species that can dominate both subtidal and intertidal habitats along the east coast of the USA. Our goal was to determine whether prevalence and intensity of Perkinsus marinus (the causative agent of Dermo disease) infections vary along intertidal to subtidal gradients during summer. We used (1) field experiments conducted at 4 sites in the Chesapeake Bay and a Virginia coastal bay, (2) a controlled air-exposure experiment, and (3) field surveys from 7 sites ranging from Maine to North Carolina to test for effects of tidal exposure on infection. Results from our field surveys suggested that high intertidal oysters tend to have higher infection prevalence than subtidal oysters, but there was no effect on infection intensity. Field experiments rarely yielded significant effects of tidal exposure on infection prevalence and intensity. Overall, our study shows that exposure to air may not be a strong driver of infection patterns in this host-parasite system. PMID:26912044

  19. Numerical quantification of Perkinsus marinus in the American oyster Crassostrea virginica (Gmelin, 1791) (Mollusca: Bivalvia) by modern stereology.

    PubMed

    Remacha-Triviño, Antonio; Borsay-Horowitz, Doranne; Dungan, Christopher; Gual-Arnau, Ximo; Gómez-Leon, Javier; Villamil, Luisa; Gómez-Chiarri, Marta

    2008-02-01

    Species of Perkinsus are responsible for high mortalities of bivalve molluscs world-wide. Techniques to accurately estimate parasites in tissues are required to improve understanding of perkinsosis. This study quantifies the number and tissue distribution of Perkinsus marinus in Crassostrea virginica by modern stereology and immunohistochemistry. Mean total number of trophozoites were (mean +/- SE) 11.80 +/- 3.91 million and 11.55 +/- 3.88 million for the optical disector and optical fractionator methods, respectively. The mean empirical error between both stereological approaches was 3.8 +/- 1.0%. Trophozoites were detected intracellularly in the following tissues: intestine (30.1%), Leydig tissue (21.3%), hemocytes (14.9%), digestive gland (11.4%), gills (6.1%), connective tissues (5.7%), gonads (4.1%), palps (2.2%), muscle (1.9%), mantle connective (0.8%), pericardium (0.7%), mantle epithelium (0.1%), and heart (0.1%). The remaining 0.6% were found extracellularly. Percentages of trophozoite stages were (mean +/- SE): large, log-phase trophonts, i.e., signet rings, 97.0 +/- 1.2%; meronts, 2.0 +/- 0.9%; clusters of small, log-phase trophonts, i.e., merozoites, 1.0 +/- 0.5%. Levels of infection in hemocytes and Leydig tissue were representative of total parasite intensity. These techniques are a powerful tool to follow parasite distribution and invasion, and to further explore mechanisms of Perkinsus spp. pathogenesis in bivalves. PMID:18372631

  20. Identification of squalamine in the plasma membrane of white blood cells in the sea lamprey, Petromyzon marinus.

    PubMed

    Yun, Sang-Seon; Li, Weiming

    2007-12-01

    It is well established that innate mechanisms play an important role in the immunity of fish. Antimicrobial peptides have been isolated and characterized from several species of teleosts. Here, we report the isolation of an antimicrobial compound from the blood of bacterially challenged sea lamprey, Petromyzon marinus. An acetic acid extract from the blood cells of challenged fish was subjected to solid-phase extraction, cation-exchange chromatography, gel-filtration chromatography, and reverse-phase high-performance liquid chromatography, with the purified fractions assayed for antimicrobial activity. Surprisingly, antimicrobial activity in these fractions originated from squalamine, an aminosterol previously identified in the dogfish shark, Squalus acanthias. Further chromatographic and mass spectrometric analyses confirmed the identity of squalamine, an antimicrobial and antiangiogenic agent, in the active fraction from the sea lamprey blood cells. Immunocytochemical analysis localized squalamine to the plasma membrane of white blood cells. Therefore, we postulate that squalamine has an important role in the innate immunity that defends the lamprey against microbial invasion. The full biochemical and immunological roles of squalamine in the white blood cell membrane remain to be investigated. PMID:17726196

  1. Formation of ursodeoxycholic acid from chenodeoxycholic acid by a 7 beta-hydroxysteroid dehydrogenase-elaborating Eubacterium aerofaciens strain cocultured with 7 alpha-hydroxysteroid dehydrogenase-elaborating organisms.

    PubMed Central

    MacDonald, I A; Rochon, Y P; Hutchison, D M; Holdeman, L V

    1982-01-01

    A gram-positive, anaerobic, chain-forming, rod-shaped anaerobe (isolate G20-7) was isolated from normal human feces. This organism was identified by cellular morphology as well as fermentative and biochemical data as Eubacterium aerofaciens. When isolate G20-7 was grown in the presence of Bacteroides fragilis or Escherichia coli (or another 7 alpha-hydroxysteroid dehydrogenase producer) and chenodeoxycholic acid, ursodeoxycholic acid produced. Time course curves revealed that 3 alpha-hydroxy-7-keto-5 beta-cholanoic acid produced by B. fragilis or E. coli or introduced into the medium as a pure substance was reduced by G20-7 specifically to ursodeoxycholic acid. The addition of glycine- and taurine-conjugated primary bile acids (chenodeoxycholic and cholic acids) and other bile acids to binary cultures of B. fragilis and G20-7 revealed that (i) both conjugates were hydrolyzed to give free bile acids, (ii) ursocholic acid (3 alpha, 7 beta, 12 alpha-trihydroxy-5 beta-cholanoic acid) was produced when conjugated (or free) cholic acid was the substrate, and (iii) the epimerization reaction was at least partially reversible. Corroborating these observations, an NADP-dependent 7 beta-hydroxysteroid dehydrogenase (reacting specifically with 7 beta-OH-groups) was demonstrated in cell-free preparations of isolate G20-7; production of the enzyme was optimal at between 12 and 18 h of growth. This enzyme, when measured in the oxidative direction, was active with ursodeoxycholic acid, ursocholic acid, and the taurine conjugate of ursodeoxycholic acid (but not with chenodeoxycholic, deoxycholic, or cholic acids) and displayed an optimal pH range of 9.8 to 10.2 Images PMID:6758698

  2. Size control of in vitro synthesized magnetite crystals by the MamC protein of Magnetococcus marinus strain MC-1.

    PubMed

    Valverde-Tercedor, C; Montalbán-López, M; Perez-Gonzalez, T; Sanchez-Quesada, M S; Prozorov, T; Pineda-Molina, E; Fernandez-Vivas, M A; Rodriguez-Navarro, A B; Trubitsyn, D; Bazylinski, Dennis A; Jimenez-Lopez, C

    2015-06-01

    Magnetotactic bacteria are a diverse group of prokaryotes that share the unique ability of biomineralizing magnetosomes, which are intracellular, membrane-bounded crystals of either magnetite (Fe3O4) or greigite (Fe3S4). Magnetosome biomineralization is mediated by a number of specific proteins, many of which are localized in the magnetosome membrane, and thus is under strict genetic control. Several studies have partially elucidated the effects of a number of these magnetosome-associated proteins in the control of the size of magnetosome magnetite crystals. However, the effect of MamC, one of the most abundant proteins in the magnetosome membrane, remains unclear. In this present study, magnetite nanoparticles were synthesized inorganically in free-drift experiments at 25 °C in the presence of different concentrations of the iron-binding recombinant proteins MamC and MamCnts (MamC without its first transmembrane segment) from the marine, magnetotactic bacterium Magnetococcus marinus strain MC-1 and three commercial proteins [α-lactalbumin (α-Lac), myoglobin (Myo), and lysozyme (Lyz)]. While no effect was observed on the size of magnetite crystals formed in the presence of the commercial proteins, biomimetic synthesis in the presence of MamC and MamCnts at concentrations of 10-60 μg/mL resulted in the production of larger and more well-developed magnetite crystals (~30-40 nm) compared to those of the control (~20-30 nm; magnetite crystals grown protein-free). Our results demonstrate that MamC plays an important role in the control of the size of magnetite crystals and could be utilized in biomimetic synthesis of magnetite nanocrystals. PMID:25874532

  3. A sea lamprey (Petromyzon marinus) sex pheromone mixture increases trap catch relative to a single synthesized component in specific environments

    USGS Publications Warehouse

    Johnson, Nicholas S.; Tix, John A.; Hlina, Benjamin L.; Wagner, C. Michael; Siefkes, Michael J.; Wang, Huiyong; Li, Weiming

    2015-01-01

    Spermiating male sea lamprey (Petromyzon marinus) release a sex pheromone, of which a component, 7α, 12α, 24-trihydoxy-3-one-5α-cholan-24-sulfate (3kPZS), has been identified and shown to induce long distance preference responses in ovulated females. However, other pheromone components exist, and when 3kPZS alone was used to control invasive sea lamprey populations in the Laurentian Great Lakes, trap catch increase was significant, but gains were generally marginal. We hypothesized that free-ranging sea lamprey populations discriminate between a partial and complete pheromone while migrating to spawning grounds and searching for mates at spawning grounds. As a means to test our hypothesis, and to test two possible uses of sex pheromones for sea lamprey control, we asked whether the full sex pheromone mixture released by males (spermiating male washings; SMW) is more effective than 3kPZS in capturing animals in traditional traps (1) en route to spawning grounds and (2) at spawning grounds. At locations where traps target sea lampreys en route to spawning grounds, SMW-baited traps captured significantly more sea lampreys than paired 3kPZS-baited traps (~10 % increase). At spawning grounds, no difference in trap catch was observed between 3kPZS and SMW-baited traps. The lack of an observed difference at spawning grounds may be attributed to increased pheromone competition and possible involvement of other sensory modalities to locate mates. Because fishes often rely on multiple and sometimes redundant sensory modalities for critical life history events, the addition of sex pheromones to traditionally used traps is not likely to work in all circumstances. In the case of the sea lamprey, sex pheromone application may increase catch when applied to specifically designed traps deployed in streams with low adult density and limited spawning habitat.

  4. Steroid-induced protein synthesis in giant-toad (Bufo marinus) urinary bladders. Correlation with natriferic activity.

    PubMed Central

    Geheb, M; Alvis, R; Owen, A; Hercker, E; Cox, M

    1984-01-01

    We have identified a group of proteins (Mr approximately 70 000-80 000; pI approximately 5.5-6.0) in giant-toad (Bufo marinus) urinary bladders whose synthesis appears to be related to aldosterone-stimulated Na+ transport. Spironolactone, a specific mineralocorticoid antagonist in renal epithelia, inhibits the synthesis of these proteins as well as the natriferic effect of the hormone. Since a variety of other steroids (some of which are traditionally considered to be glucocorticoids) also stimulate Na+ transport in toad urinary bladders, we examined whether their natriferic activity was expressed in a fashion similar to that of aldosterone. Short-circuit current was used to measure Na+ transport, and epithelial-cell protein synthesis was detected with high-resolution two-dimensional polyacrylamide-gel electrophoresis and autoradiography. At a concentration of approximately 100 nM, dexamethasone, corticosterone and aldosterone were equinatriferic. Dexamethasone and aldosterone had identical dose-response curves, maximal and half-maximal activity being evident at concentrations of approximately 100 nM and 10 nM respectively. In contrast, at a concentration of approximately 10 nM, corticosterone had no effect on Na+ transport. The natriferic activities of these three steroids correlate with their known affinities for the putative mineralocorticoid receptor in toad urinary bladders. Natriferic concentrations of dexamethasone and corticosterone (140 nM) induced the synthesis of proteins with characteristics identical with those induced by aldosterone. Spironolactone, at an antagonist/agonist ratio of 2000:1, inhibited steroid-induced Na+ transport and the synthesis of these proteins. Thus it appears that all natriferic steroids share a common mechanism of action in toad urinary bladders. Natriferic activity can be correlated not only with relative steroid-receptor affinity but also with the induction of a specific group of epithelial-cell proteins. Images Fig. 1. Fig

  5. Survival and metamorphosis of low-density populations of larval sea lampreys (Petromyzon marinus) in streams following lampricide treatment

    USGS Publications Warehouse

    Johnson, Nicholas S.; Swink, William D.; Brenden, Travis O.; Slade, Jeffrey W.; Steeves, Todd B.; Fodale, Michael F.; Jones, Michael L.

    2014-01-01

    Sea lamprey Petromyzon marinus control in the Great Lakes primarily involves application of lampricides to streams where larval production occurs to kill larvae prior to their metamorphosing and entering the lakes as parasites (juveniles). Because lampricides are not 100% effective, larvae that survive treatment maymetamorphose before streams are again treated. Larvae that survive treatment have not beenwidely studied, so their dynamics are notwell understood.Wetagged and released larvae in six Great Lake tributaries following lampricide treatment and estimated vital demographic rates using multistate tag-recovery models. Model-averaged larval survivals ranged from 56.8 to 57.6%. Model-averaged adult recovery rates, which were the product of juvenile survivals and adult capture probabilities, ranged from 6.8 to 9.3%. Using stochastic simulations, we estimated production of juvenile sea lampreys from a hypothetical population of treatment survivors under different growth conditions based on parameter estimates from this research. For fast-growing populations, juvenile production peaked 2 years after treatment. For slow-growing populations, juvenile production was approximately one-third that of fast-growing populations,with production not peaking until 4 years after treatment. Our results suggest that dynamics (i.e., survival, metamorphosis) of residual larval populations are very similar to those of untreated larval populations. Consequently, residual populations do not necessarily warrant special consideration for the purpose of sea lamprey control and can be ranked for treatment along with other populations. Consecutive lampricide treatments, which are under evaluation by the sea lamprey control program, would bemost effective for reducing juvenile production in large, fast-growing populations.

  6. Magnetococcus marinus gen. nov., sp. nov., a marine, magnetotactic bacterium that represents a novel lineage (Magnetococcaceae fam. nov., Magnetococcales ord. nov.) at the base of the Alphaproteobacteria.

    PubMed

    Bazylinski, Dennis A; Williams, Timothy J; Lefèvre, Christopher T; Berg, Ryan J; Zhang, Chuanlun L; Bowser, Samuel S; Dean, Annette J; Beveridge, Terrence J

    2013-03-01

    Magnetotactic bacteria are a morphologically, metabolically and phylogenetically disparate array of bacteria united by the ability to biomineralize membrane-encased, single-magnetic-domain mineral crystals (magnetosomes) that cause the cell to orientate along the Earth's geomagnetic field. The most commonly observed type of magnetotactic bacteria is the ubiquitous magnetotactic cocci, which comprise their own phylogenetic group. Strain MC-1(T), a member of this group, was isolated from water collected from the oxic-anoxic interface of the Pettaquamscutt Estuary in Rhode Island, USA, and cultivated in axenic culture. Cells of strain MC-1(T) are roughly spherical, with two sheathed bundles of flagella at a single pole (bilophotrichous). Strain MC-1(T) uses polar magnetotaxis, and has a single chain of magnetite crystals per cell. Cells grow chemolithoautotrophically with thiosulfate or sulfide as the electron donors, and chemo-organoheterotrophically on acetate. During autotrophic growth, strain MC-1(T) relies on the reductive tricarboxylic acid cycle for CO2 fixation. The DNA G+C content is 54.2 mol%. The new genus and species Magnetococcus marinus gen. nov., sp. nov. are proposed to accommodate strain MC-1(T) ( = ATCC BAA-1437(T)  = JCM 17883(T)), which is nominated as the type strain of Magnetococcus marinus. A new order (Magnetococcales ord. nov.) and family (Magnetococcaceae fam. nov.) are proposed for the reception of Magnetococcus and related magnetotactic cocci, which are provisionally included in the Alphaproteobacteria as the most basal known lineage of this class. PMID:22581902

  7. INTERACTIONS OF CHLORINE-PRODUCED OXIDANTS (CPO) AND SALINITY IN AFFECTING LETHAL AND SUBLETHAL EFFECTS IN THE EASTERN OR AMERICAN OYSTER, 'CRASSOSTREA VIRGINICA' (GMELIN), INFECTED WITH THE PROTISTAN PARASITE, 'PERKINSUS MARINUS'

    EPA Science Inventory

    Exposure of oysters, infected with the protistan parasite, Perkinsus marinus, to high salinity and high salinity, chlorine-produced oxidants (CPO) conditions was quite toxic. The combination of high salinity and CPO exposure generally increased toxicity above levels measured in h...

  8. Cloning, DNA sequencing, and characterization of a nifD-homologous gene from the archaeon Methanosarcina barkeri 227 which resembles nifD1 from the eubacterium Clostridium pasteurianum.

    PubMed Central

    Chien, Y T; Zinder, S H

    1994-01-01

    L. Sibold, M. Henriquet, O. Possot, and J.-P. Aubert (Res. Microbiol. 142:5-12, 1991) cloned and sequenced two nifH-homologous open reading frames (ORFs) from Methanosarcina barkeri 227. Phylogenetic analysis of the deduced amino acid sequences of the nifH ORFs from M. barkeri showed that nifH1 clusters with nifH genes from alternative nitrogenases, while nifH2 clusters with nifH1 from the gram-positive eubacterium Clostridium pasteurianum. The N-terminal sequence of the purified nitrogenase component 2 (the nifH gene product) from M. barkeri was identical with that predicted for nifH2, and dot blot analysis of RNA transcripts indicated that nifH2 (and nifDK2) was expressed in M. barkeri when grown diazotrophically in Mo-containing medium. To obtain nifD2 from M. barkeri, a 4.7-kbp BamHI fragment of M. barkeri DNA was cloned which contained at least five ORFs, including nifH2, ORF105, and ORF125 (previously described by Sibold et al.), as well as nifD2 and part of nifK2. ORFnifD2 is 1,596 bp long and encodes 532 amino acid residues, while the nifK2 fragment is 135 bp long. The deduced amino acid sequences for nifD2 and the nifK2 fragment from M. barkeri cluster most closely with the corresponding nifDK1 gene products from C. pasteurianum. The predicted M. barkeri nifD2 product contains a 50-amino acid insert near the C terminus which has previously been found only in the clostridial nifD1 product. Previous biochemical and sequencing evidence indicates that the C. pasteurianum nitrogenase is the most divergent of known eubacterial Mo-nitrogenases, most likely representing a distinct nif gene family, which now also contains M. barkeri as a member. The similarity between the methanogen and clostridial nif sequences is especially intriguing in light of the recent findings of sequence similarities between gene products from archaea and from low-G+C gram-positive eubacteria for glutamate dehydrogenase, glutamine synthetase I, and heat shock protein 70. It is not clear

  9. Defining optimal freshwater flow for oyster production: effects of freshet rate and magnitude of change and duration on eastern oysters and Perkinsus marinus infection

    USGS Publications Warehouse

    LaPeyre, Megan K.; Gossman, B.; La Peyre, Jerome F.

    2009-01-01

    In coastal Louisiana, the development of large-scale freshwater diversion projects has led to controversy over their effects on oyster resources. Using controlled laboratory experiments in combination with a field study, we examined the effects of pulsed freshwater events (freshet) of different magnitude, duration, and rate of change on oyster resources. Laboratory and field evidence indicate that low salinity events (<5 psu) decreased Perkinsus marinus infection intensities. Furthermore, when salinity was low (<5 psu), parasite infection intensities continued to decrease even as temperatures exceeded 20°C. At the same time, oyster growth was positively correlated with salinity. To maximize oyster production, data indicate that both low and high salinity events will be necessary.

  10. The influence of environmental factors on the population dynamics, reproductive biology and productivity of Echinogammarus marinus Leach (Amphipoda, Gammaridae) in the Mondego estuary (Portugal)

    NASA Astrophysics Data System (ADS)

    Maranhão, Paulo; Bengala, Nuno; Pardal, Miguel; Marques, João Carlos

    2001-06-01

    The population density of Echinogammarus marinus in the Mondego estuary changed throughout the year, with a maximum during spring. The lowest densities were found in the north arm of the estuary, and the highest ones in the inner areas of the south arm. Higher densities appeared associated with the presence of muddy deposits under Fucus vesiculosus (Phaeophyta) and also with the presence of green macroalgae biomass over the sediments. Females were morphologically recognisable at smaller sizes than males, but males became larger than females. Fecundity increases with the size of females and is influenced by temperature and salinity. Sexual activity and recruitment take place continuously throughout the year, although it almost ceases by the end of winter. Present results are in opposition to the hypothesis of discontinuous recruitment presented in a previous study. Productivity (ash free dry weight- AFDW) was estimated at 1.74 to 2.45 g·m -2·year -1 in the north arm of the estuary corresponding to an annual turnover ratio ( P/ B¯) of 4.14 to 6.18. In the south arm, productivity was estimated at 1.96 to 2.74 g AFDW·m -2·year -1 in the middle section ( P/ B¯ of 4.68 to 6.56), and at 3.85 to 5.38 g AFDW·m -2·year -1 in the innermost sampling area ( P/ B¯ of 4.54 to 6.36). Differences in productivity appeared to depend only on population density, while annual P/ B¯ ratios were similar over the estuary. Evidence was found that several features of E. marinus population dynamics were dependent on environmental factors resulting from the particular estuary hydraulic regime.

  11. Lachnoanaerobaculum gen. nov., a new genus in the Lachnospiraceae: characterization of Lachnoanaerobaculum umeaense gen. nov., sp. nov., isolated from the human small intestine, and Lachnoanaerobaculum orale sp. nov., isolated from saliva, and reclassification of Eubacterium saburreum (Prévot 1966) Holdeman and Moore 1970 as Lachnoanaerobaculum saburreum comb. nov.

    PubMed Central

    Moore, Edward R. B.; Svensson-Stadler, Liselott; Hörstedt, Per; Baranov, Vladimir; Hernell, Olle; Wai, Sun Nyunt; Hammarström, Sten; Hammarström, Marie-Louise

    2012-01-01

    Two novel obligately anaerobic, Gram-stain-positive, saccharolytic and non-proteolytic spore-forming bacilli (strains CD3 : 22T and N1T) are described. Strain CD3 : 22T was isolated from a biopsy of the small intestine of a child with coeliac disease, and strain N1T from the saliva of a healthy young man. The cells of both strains were observed to be filamentous, approximately 5 to >20 µm long, some of them curving and with swellings. The novel organisms produced H2S, NH3, butyric acid and acetic acid as major metabolic end products. Phylogenetic analyses, based on comparative 16S rRNA gene sequencing, revealed close relationships (98 % sequence similarity) between the two isolates, as well as the type strain of Eubacterium saburreum and four other Lachnospiraceae bacterium-/E. saburreum-like organisms. This group of bacteria were clearly different from any of the 19 known genera in the family Lachnospiraceae. While Eubacterium species are reported to be non-spore-forming, reanalysis of E. saburreum CCUG 28089T confirmed that the bacterium is indeed able to form spores. Based on 16S rRNA gene sequencing, phenotypic and biochemical properties, strains CD3 : 22T and N1T represent novel species of a new and distinct genus, named Lachnoanaerobaculum gen. nov., in the family Lachnospiraceae [within the order Clostridiales, class Clostridia, phylum Firmicutes]. Strain CD3 : 22T ( = CCUG 58757T  = DSM 23576T) is the type strain of the type species, Lachnoanaerobaculum umeaense gen. nov., sp. nov., of the proposed new genus. Strain N1T ( = CCUG 60305T = DSM 24553T) is the type strain of Lachnoanaerobaculum orale sp. nov. Moreover, Eubacterium saburreum is reclassified as Lachnoanaerobaculum saburreum comb. nov. (type strain CCUG 28089T  = ATCC 33271T  = CIP 105341T  = DSM 3986T  = JCM 11021T  = VPI 11763T). PMID:22228654

  12. Assessment of the cell viability of cultured Perkinsus marinus (Perkinsea), a parasitic protozoan of the Eastern oyster, Crassostrea virginica, using SYBRgreen-propidium iodide double staining and flow cytometry.

    PubMed

    Soudant, Philippe; Chu, Fu-Lin E; Lund, Eric D

    2005-01-01

    A flow cytometry (FCM) assay using SYBRgreen and propidium iodide double staining was tested to assess viability and morphological parameters of Perkinsus marinus under different cold- and heat-shock treatments and at different growth phases. P. marinus meront cells, cultivated at 28 degrees C, were incubated in triplicate for 30 min at -80 degrees C, -20 degrees C, 5 degrees C, and 20 degrees C for cold-shock treatments and at 32 degrees C, 36 degrees C, 40 degrees C, 44 degrees C, 48 degrees C, 52 degrees C, and 60 degrees C for heat-shock treatments. A slight and significant decrease in percentage of viable cells (PVC), from 93.6% to 92.7%, was observed at -20 degrees C and the lowest PVC was obtained at -80 degrees C (54.0%). After 30 min of heat shocks at 40 degrees C and 44 degrees C, PVC decreased slightly but significantly compared to cells maintained at 28 degrees C. When cells were heat shocked at 48 degrees C, 52 degrees C, and 60 degrees C heavy mortality occurred and PVC decreased to 33.8%, 8.0%, and 3.4%, respectively. No change in cell complexity and size was noted until cells were heat shocked at >or=44 degrees C. High cell mortality was detected at stationary phase of P. marinus cell culture. Cell viability dropped below 40% in 28-day-old cultures and ranged 11-25% in 38 to 47-day-old cultures. Results suggest that FCM could be a useful tool for determining viability of cultured P. marinus cells. PMID:16313441

  13. Life stage dependent responses to the lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), provide insight into glucose homeostasis and metabolism in the sea lamprey (Petromyzon marinus).

    PubMed

    Henry, Matthew; Birceanu, Oana; Clifford, Alexander M; McClelland, Grant B; Wang, Yuxiang S; Wilkie, Michael P

    2015-03-01

    The primary method of sea lamprey (Petromyzon marinus) control in the Great Lakes is the treatment of streams and rivers with the pesticide 3-trifluoromethyl-4-nitrophenol (TFM), which targets larval sea lamprey. However, less is known about the effects of TFM on other stages of the sea lamprey's complex life cycle. The goal of this study was to determine how TFM affected internal energy stores, metabolites, and ion balance in larval, juvenile (parasitic) and adult sea lamprey. The larvae were more tolerant to TFM than the adults, with a 2-fold higher 12h TFM LC50 and a 1.5-fold higher LC99.9. Acute (3h) exposure of the larvae, parasites and adults to their respective 12h TFM LC99.9 led to marked reductions in glycogen and phosphocreatine in the adult brain, with lesser or no effect in the larvae and parasites. Increased lactate in the brain, at less than the expected stoichiometry, suggested that it was exported to the blood. Kidney glycogen declined after TFM exposure, suggesting that this organ plays an important role in glucose homeostasis. TFM-induced disturbances to ion balance were minimal. In conclusion, TFM perturbs energy metabolism in all major stages of the sea lamprey life cycle in a similar fashion, but the adults appear to be the most sensitive. Thus, the adult stage could be a viable and effective target for TFM treatment, particularly when used in combination with other existing and emerging strategies of sea lamprey control. PMID:25576187

  14. Assessment of sea lamprey (Petromyzon marinus) predation by recovery of dead lake trout (Salvelinus namaycush) from Lake Ontario, 1982-85

    USGS Publications Warehouse

    Bergstedt, Roger A.; Schneider, Clifford P.

    1988-01-01

    During 1982-85, 89 dead lake trout (Salvelinus namaycush) were recovered with bottom trawls in U.S. waters of Lake Ontario: 28 incidentally during four annual fish-stock assessment surveys and 61 during fall surveys for dead fish. During the assessment surveys, no dead lake trout were recovered in April-June, one was recovered in August, and 27 were recovered in October or November, implying that most mortality from causes other than fishing occurred in the fall. The estimated numbers of dead lake trout between the 30- and 100-m depth contours in U.S. waters ranged from 16 000 (0.08 carcass/ha) in 1983 to 94 000 (0.46 carcass/ha) in 1982. Of 76 carcasses fresh enough to enable recognition of sea lamprey (Petromyzon marinus) wounds, 75 bore fresh wounds. Assuming that sea lamprey wounding rates on dead fish were the same as on live ones of the same length range (430-740 mm), the probability of 75 of the 76 dead lake trout bearing sea lamprey wounds was 3.5 x 10-63 if death was independent of sea lamprey attack, thus strongly implicating sea lampreys as the primary cause of death of fish in the sample. The recovery of only one unwounded dead lake trout also suggested that natural mortality from causes other than sea lamprey attactks is negligible.

  15. Population ecology of the sea lamprey (Petromyzon marinus) as an invasive species in the Laurentian Great Lakes and an imperiled species in Europe

    USGS Publications Warehouse

    Hansen, Michael J.; Madenjian, Charles P.; Slade, Jeffrey W.; Steeves, Todd B.; Almeida, Pedro R.; Quintella, Bernardo R.

    2016-01-01

    The sea lamprey Petromyzon marinus (Linnaeus) is both an invasive non-native species in the Laurentian Great Lakes of North America and an imperiled species in much of its native range in North America and Europe. To compare and contrast how understanding of population ecology is useful for control programs in the Great Lakes and restoration programs in Europe, we review current understanding of the population ecology of the sea lamprey in its native and introduced range. Some attributes of sea lamprey population ecology are particularly useful for both control programs in the Great Lakes and restoration programs in the native range. First, traps within fish ladders are beneficial for removing sea lampreys in Great Lakes streams and passing sea lampreys in the native range. Second, attractants and repellants are suitable for luring sea lampreys into traps for control in the Great Lakes and guiding sea lamprey passage for conservation in the native range. Third, assessment methods used for targeting sea lamprey control in the Great Lakes are useful for targeting habitat protection in the native range. Last, assessment methods used to quantify numbers of all life stages of sea lampreys would be appropriate for measuring success of control in the Great Lakes and success of conservation in the native range.

  16. CRISPR/Cas9-mediated mutagenesis in the sea lamprey Petromyzon marinus: a powerful tool for understanding ancestral gene functions in vertebrates.

    PubMed

    Square, Tyler; Romášek, Marek; Jandzik, David; Cattell, Maria V; Klymkowsky, Michael; Medeiros, Daniel M

    2015-12-01

    Lamprey is one of only two living jawless vertebrates, a group that includes the first vertebrates. Comparisons between lamprey and jawed vertebrates have yielded important insights into the origin and evolution of vertebrate physiology, morphology and development. Despite its key phylogenetic position, studies of lamprey have been limited by their complex life history, which makes traditional genetic approaches impossible. The CRISPR/Cas9 system is a bacterial defense mechanism that was recently adapted to achieve high-efficiency targeted mutagenesis in eukaryotes. Here we report CRISPR/Cas9-mediated disruption of the genes Tyrosinase and FGF8/17/18 in the sea lamprey Petromyzon marinus, and detail optimized parameters for producing mutant F0 embryos. Using phenotype and genotype analyses, we show that CRISPR/Cas9 is highly effective in the sea lamprey, with a majority of injected embryos developing into complete or partial mutants. The ability to create large numbers of mutant embryos without inbred lines opens exciting new possibilities for studying development in lamprey and other non-traditional model organisms with life histories that prohibit the generation of mutant lines. PMID:26511928

  17. Comparison of spring measures of length, weight, and condition factor for predicting metamorphosis in two populations of sea lampreys (Petromyzon marinus) larvae

    USGS Publications Warehouse

    Henson, Mary P.; Bergstedt, Roger A.; Adams, Jean V.

    2003-01-01

    The ability to predict when sea lampreys (Petromyzon marinus) will metamorphose from the larval phase to the parasitic phase is essential to the operation of the sea lamprey control program. During the spring of 1994, two populations of sea lamprey larvae from two rivers were captured, measured, weighed, implanted with coded wire tags, and returned to the same sites in the streams from which they were taken. Sea lampreys were recovered in the fall, after metamorphosis would have occurred, and checked for the presence of a tag. When the spring data were compared to the fall data it was found that the minimum requirements (length ≥ 120 mm, weight ≥ 3 g, and condition factor ≥ 1.50) suggested for metamorphosis did define a pool of larvae capable of metamorphosing. However, logistic regressions that relate the probability of metamorphosis to size are necessary to predict metamorphosis in a population. The data indicated, based on cross-validation, that weight measurements alone predicted metamorphosis with greater precision than length or condition factor in both the Marengo and Amnicon rivers. Based on the Akaike Information Criterion, weight alone was a better predictor in the Amnicon River, but length and condition factor combined predicted metamorphosis better in the Marengo River. There would be no additional cost if weight alone were used instead of length. However, if length and weight were measured the gain in predictive power would not be enough to justify the additional cost.

  18. Evidence that sea lampreys (Petromyzon marinus) complete their life cycle within a tributary of the Laurentian Great Lakes by parasitizing fishes in inland lakes

    USGS Publications Warehouse

    Johnson, Nicholas; Twohey, Michael B.; Miehls, Scott M.; Cwalinski, Tim A; Godby, Neal A; Lochet, Aude; Slade, Jeffrey W.; Jubar, Aaron K.; Siefkes, Michael J.

    2015-01-01

    The sea lamprey (Petromyzon marinus) invaded the upper Laurentian Great Lakes and feeds on valued fish. The Cheboygan River, Michigan, USA, is a large sea lamprey producing tributary to Lake Huron and despite having a renovated dam 2 km from the river mouth that presumably blocks sea lamprey spawning migrations, the watershed upstream of the dam remains infested with larval sea lamprey. A navigational lock near the dam has been hypothesized as the means of escapement of adult sea lampreys from Lake Huron and source of the upper river population (H1). However, an alternative hypothesis (H2) is that some sea lampreys complete their life cycle upstream of the dam, without entering Lake Huron. To evaluate the alternative hypothesis, we gathered angler reports of lamprey wounds on game fishes upstream of the dam, and captured adult sea lampreys downstream and upstream of the dam to contrast abundance, run timing, size, and statolith microchemistry. Results indicate that a small population of adult sea lampreys (n < 200) completed their life cycle upstream of the dam during 2013 and 2014. This is the most comprehensive evidence that sea lampreys complete their life history within a tributary of the upper Great Lakes, and indicates that similar landlocked populations could occur in other watersheds. Because the adult sea lamprey population upstream of the dam is small, complete elimination of the already low adult escapement from Lake Huron might allow multiple control tactics such as lampricides, trapping, and sterile male release to eradicate the population.

  19. Morphological and electrophysiological examination of olfactory sensory neurons during the early developmental prolarval stage of the sea lamprey Petromyzon marinus L

    USGS Publications Warehouse

    Zielinski, B.S.; Fredricks, Keith; McDonald, R.; Zaidi, A.U.

    2005-01-01

    This study examined olfactory sensory neuron morphology and physiological responsiveness in newly hatched sea lamprey, Petromyzon marinus L. These prolarvae hatch shortly after neural tube formation, and stay within nests for approximately 18 days, before moving downstream to silty areas where they burrow, feed and pass to the larval stage. To explore the possibility that the olfactory system is functioning during this prolarval stage, morphological and physiological development of olfactory sensory neurons was examined. The nasal cavity contained an olfactory epithelium with ciliated olfactory sensory neurons. Axons formed aggregates in the basal portion of the olfactory epithelium and spanned the narrow distance between the olfactory epithelium and the brain. The presence of asymmetric synapses with agranular vesicles within fibers in the brain, adjacent to the olfactory epithelium suggests that there was synaptic connectivity between olfactory sensory axons and the brain. Neural recordings from the surface of the olfactory epithelium showed responses following the application of L-arginine, taurocholic acid, petromyzonol sulfate (a lamprey migratory pheromone), and water conditioned by conspecifics. These results suggest that lampreys may respond to olfactory sensory input during the prolarval stage. ?? 2006 Springer Science + Business Media, LLC.

  20. Estimating lake-wide abundance of spawning-phase sea lampreys (Petromyzon marinus) in the Great Lakes: extrapolating from sampled streams using regression models

    USGS Publications Warehouse

    Mullett, Katherine M.; Heinrich, John W.; Adams, Jean V.; Young, Robert J.; Henson, Mary P.; McDonald, Rodney B.; Fodale, Michael F.

    2003-01-01

    Lake-wide abundance of spawning-phase sea lampreys (Petromyzon marinus) can be used as one means to evaluate sea lamprey control efforts in the Great Lakes. Lake-wide abundance in each Great Lake was the sum of estimates for all streams thought to contribute substantial numbers of sea lampreys. A subset of these streams was sampled with traps and mark-recapture studies were conducted. When sea lampreys were captured in traps, but no mark-recapture study was conducted, abundance was estimated from a relation between trap catch and mark-recapture estimates observed in other years. In non-sampled streams, a regression model that used stream drainage area, geographic region, larval sea lamprey, production potential, the number of years since the last lampricide treatment, and spawning year was used to predict abundance of spawning-phase sea lampreys. The combination of estimates from sampled and non-sampled streams provided a 20-year time series of spawning-phase sea lamprey abundance estimates in the Great Lakes.

  1. Evaluation of strategies for the release of male sea lampreys (Petromyzon marinus) in Lake Superior for a proposed sterile-male-release program

    USGS Publications Warehouse

    Kaye, C.A.; Heinrich, J.W.; Genovese, J.H.; Hanson, L.H.; McDonald, R.B.; Slade, J.W.; Swink, W.D.

    2003-01-01

    Successful implementation of a sea lamprey (Petromyzon marinus) control technique that uses sterilized males to reduce reproduction presently depends on the importation of large numbers of males outside of the target population. Strategies were examined for releasing male sea lampreys from Lakes Michigan and Huron into the Lake Superior spawning population and the ability of these introduced males to compete with resident males and spawn with resident females. During 1987, 553 (9%) of 6,324 imported fertile males released at 12 shoreline and one offshore site in Lake Superior were recaptured. Most remained within 20 km of the release site and entered the first stream encountered. During 1988, 393 (18%) of 2,208 imported fertile males released directly into three spawning rivers were recaptured. In both cases, animals released early during the spawning run were more likely to be recaptured than those released later. Introduced males successfully competed with resident males and spawned with resident females. Demonstrating that male sea lampreys could reproduce successfully when relocated supported subsequent large-scale field trials of the sterile-male-release technique.

  2. Passage of four teleost species prior to sea lamprey (Petromyzon marinus) migration in eight tributaries of Lake Superior, 1954-1979

    USGS Publications Warehouse

    Klinger, Gregory L.; Adams, Jean V.; Heinrich, John W.

    2003-01-01

    Seasonally operated barriers in rivers are used by the Great Lakes Fishery Commission to block adult sea lamprey (Petromyzon marinus) migrations, yet pass other fish during some part of the year. Knowledge of the overlap of spawning migrations of sea lampreys and other fish species are vital for the efficient operation of the Commission's barrier program. The migration of sea lamprey spawners was compared with the migration of four other fish species using trap captures at electric barriers on eight Lake Superior tributaries during 1954 to 1979. The passage of rainbow trout (Oncorhynchus mykiss), rainbow smelt (Osmerus mordax), longnose suckers (Catostomus catostomus), and white suckers (Catostomus commersoni) prior to the capture of sea lampreys was quantified as the proportion of the annual catch of each species. Average passage over all streams and years was smallest (5%) for longnose sucker and largest (21%) for rainbow smelt. Passage prior to first sea lamprey catch was significantly different among rivers for all four species and significantly different among years for rainbow trout. Much of the variability in annual passage was unexplained by river or year effects. It is suggested that stream-specific information on run times of sea lampreys and other fishes be used to define timing of seasonal barrier operations. If barrier operations are timed to block the entire sea lamprey spawning run, then fish passage devices are needed to pass rainbow trout, rainbow smelt, longnose suckers, and white suckers.

  3. Barrientosiimonas endolithica sp. nov., isolated from pebbles, reclassification of the only species of the genus Tamlicoccus, Tamlicoccus marinus Lee 2013, as Barrientosiimonas marina comb. nov. and emended description of the genus Barrientosiimonas.

    PubMed

    Parag, B; Sasikala, Ch; Ramana, Ch V

    2015-09-01

    Strain JC268(T) was isolated from pebbles collected from a dam located in Lalitpur, Uttar Pradesh, India. Cells of strain JC268(T) were coccoid, appeared in pairs/triads/tetrads or short chains and were Gram-stain-positive, non-spore-forming, non-motile and obligately aerobic. Strain JC268(T) was catalase- and oxidase-positive and utilized citrate for growth. The genomic DNA G+C content of strain JC268(T) was 65.3 mol%. The cell-wall peptidoglycan contained L-lysine-L-serine-D-aspartic acid as interpeptide bridge with the type A4α. The major menaquinone was MK-8(H4). Major (>10%) fatty acids were iso-C16 : 0, iso-C16 : 1H and anteiso-C17 : 1ω9c. Diphosphatidylglycerol, phosphoglycolipid, phosphatidylinositol, glycolipid, four unidentified lipids, an amino lipid and phospholipid were the polar lipids of strain JC268(T). EzTaxon-e blast search of 16S rRNA gene sequences showed that strain JC268(T) has highest similarity to Barrientosiimonas humi 39(T) (98.65%) and Tamlicoccus marinus MSW-24(T) (97.8%) of the family Dermacoccaceae. Genome reassociation (based on DNA-DNA hybridization) of strain JC268(T) with Barrientosiimonas humi CGMCC 4.6864(T) ( = 39(T)) and T. marinus KCTC 19485(T) ( = MSW-24(T)) yielded values of 32.5 ± 2% and 27.3 ± 2%, respectively. Based on the data from phylogenetic and polyphasic taxonomic analyses, strain JC268(T) represents a novel species of the genus Barrientosiimonas for which the name Barrientosiimonas endolithica sp. nov., is proposed. The type strain of Barrientosiimonas endolithica is JC268(T) ( = KCTC 29672(T) = NBRC 110608(T)). Our data suggest that T. marinus should be reclassified within the genus Barrientosiimonas. Thus, a reclassification is proposed for T. marinus, the type and only species of the genus Tamlicoccus, as Barrientosiimonas marina comb. nov., which implies the emendation of the description of the genus Barrientosiimonas. PMID:26060216

  4. Changes in mortality of lake trout (Salvelinus namaycush) in Michigan waters of Lake Superior in relation to sea lamprey (Petromyzon marinus) predation, 1968-78

    USGS Publications Warehouse

    Pycha, Richard L.

    1980-01-01

    Total mortality rates of lake trout (Salvelinus namaycush) of age VII and older from eastern Lake Superior were estimated from catch curves of age distributions each year in 1968–78. The instantaneous rate of total mortality Z varied from 0.62 to 2.31 in close synchrony with sea lamprey (Petromyzon marinus) wounding rates on lake trout. The regression of transformed Z on the index of lamprey wounding, accounted for over 89% of the variation in lake trout mortality (r2 = 0.893). An iterative method of estimating rates of exploitation u, instantaneous rates of fishing mortality F, K (a constant relating sample catch per unit effort to population size), instantaneous normal natural mortality rate M, and instantaneous rate of mortality due to sea lamprey predationL from the sample catch per unit effort and total catch by the fishery is presented. A second method using the results of a 1970–71 tagging study to estimate the mean F in 1970–77 yielded closely similar results to the above and is presented as corroboration. The estimates of u, F, andM appear to be reasonable. F ranged from 0.17 in 1974 to 0.42 in 1969 and M was estimated at 0.26. L varied from 0.21 in 1974 to 1.70 in 1968. Management implications of various policies concerning sea lamprey control, exploitation, and stocking are discussed.Key words: lake trout, sea lamprey, lamprey control, mortality, predation, Lake Superior, fishery, management

  5. Investigating Population Structure of Sea Lamprey (Petromyzon marinus, L.) in Western Iberian Peninsula Using Morphological Characters and Heart Fatty Acid Signature Analyses

    PubMed Central

    Lança, Maria João; Machado, Maria; Mateus, Catarina S.; Lourenço, Marta; Ferreira, Ana F.; Quintella, Bernardo R.; Almeida, Pedro R.

    2014-01-01

    This study hypothesizes the existence of three groups of sea lamprey Petromyzon marinus L. in Portugal (North/Central group, Tagus group, and Guadiana group), possibly promoted by seabed topography isolation during the oceanic phase of the life cycle. Within this context, our purpose was to analyze the existence of a stock structure on sea lamprey populations sampled in the major Portuguese river basins using both morphological characters and heart tissue fatty acid signature. In both cases, the multiple discriminant analysis revealed statistically significant differences among groups, and the overall corrected classification rate estimated from cross-validation procedure was particularly high for the cardiac muscle fatty acid profiles (i.e. 83.8%). Morphometric characters were much more useful than meristic ones to discriminate stocks, and the most important variables for group differentiation were eye length, second dorsal fin length and branchial length. Fatty acid analysis showed that all lampreys from the southern Guadiana group were correctly classified and not mixing with individuals from any other group, reflecting a typical heart fatty acid signature. Our results revealed that 89.5% and 72.2% of the individuals from the Tagus and North/Central groups, respectively, were also correctly classified, despite some degree of overlap between individuals from these groups. The fatty acids that contributed to the observed segregation were C16:0; C17:0; C18:1ω9; C20:3ω6 and C22:2ω6. Detected differences are probably related with environmental variables to which lampreys may have been exposed, which leaded to different patterns of gene expression. These results suggest the existence of three different sea lamprey stocks in Portugal, with implication in terms of management and conservation. PMID:25259723

  6. Contaminant levels in Herring (Larus argentatus) and Great Black-backed Gull (Larus marinus) eggs from colonies in the New York harbor complex between 2012 and 2013

    PubMed Central

    Elbin, Susan

    2014-01-01

    Birds living in coastal areas are exposed to severe storms and tidal flooding during the nesting season, but also to contaminants that move up the food chain from the water column and sediment to their prey items. We examine metals in Herring Gull (Larus argentatus) and Great Black-backed Gull (Larus marinus) eggs collected from the New York/New Jersey harbor estuary in 2012 and in 2013 to determine if there were significant yearly differences in metal levels. We test the null hypothesis that there were no significant yearly differences in metal levels. We investigate whether there were consistent differences in metals from 2012 to 2013 that might suggest a storm-related effect because Superstorm Sandy landed in New Jersey in October 2012 with high winds and extensive flooding, and view this research as exploratory. Except for arsenic, there were significant inter-year variations in the mean levels for all colonies combined for Herring Gull, and for lead, mercury and selenium for Great Black-backed Gulls. All metal levels in 2013 were less than in 2012, except for lead. These differences were present for individual colonies as well. Metal levels varied significantly among islands for Herring Gulls in both years (except for cadmium in 2013). No one colony had the highest levels of all metals for Herring Gulls. A long term data set on mercury levels in Herring Gulls indicated that the differences between 2012 and 2013 were greater than usual. Several different factors could account for these differences, and these are discussed. PMID:25471353

  7. The emergence of the vasopressin and oxytocin hormone receptor gene family lineage: Clues from the characterization of vasotocin receptors in the sea lamprey (Petromyzon marinus).

    PubMed

    Mayasich, Sally A; Clarke, Benjamin L

    2016-01-15

    The sea lamprey (Petromyzon marinus) is a jawless vertebrate at an evolutionary nexus between invertebrates and jawed vertebrates. Lampreys are known to possess the arginine vasotocin (AVT) hormone utilized by all non-mammalian vertebrates. We postulated that the lamprey would possess AVT receptor orthologs of predecessors to the arginine vasopressin (AVP)/oxytocin (OXT) family of G protein-coupled receptors found in mammals, providing insights into the origins of the mammalian V1A, V1B, V2 and OXT receptors. Among the earliest animals to diverge from the vertebrate lineage in which these receptors are characterized is the jawed, cartilaginous elephant shark, which has genes orthologous to all four mammalian receptor types. Therefore, our work was aimed at helping resolve the critical gap concerning the outcomes of hypothesized large-scale (whole-genome) duplication events. We sequenced one partial and four full-length putative lamprey AVT receptor genes and determined their mRNA expression patterns in 15 distinct tissues. Phylogenetically, three of the full-coding genes possess structural characteristics of the V1 clade containing the V1A, V1B and OXT receptors. Another full-length coding gene and the partial sequence are part of the V2 clade and appear to be most closely related to the newly established V2B and V2C receptor subtypes. Our synteny analysis also utilizing the Japanese lamprey (Lethenteron japonicum) genome supports the recent proposal that jawless and jawed vertebrates shared one-round (1R) of WGD as the most likely scenario. PMID:26764211

  8. Investigating population structure of Sea Lamprey (Petromyzon marinus, L.) in Western Iberian Peninsula using morphological characters and heart fatty acid signature analyses.

    PubMed

    Lança, Maria João; Machado, Maria; Mateus, Catarina S; Lourenço, Marta; Ferreira, Ana F; Quintella, Bernardo R; Almeida, Pedro R

    2014-01-01

    This study hypothesizes the existence of three groups of sea lamprey Petromyzon marinus L. in Portugal (North/Central group, Tagus group, and Guadiana group), possibly promoted by seabed topography isolation during the oceanic phase of the life cycle. Within this context, our purpose was to analyze the existence of a stock structure on sea lamprey populations sampled in the major Portuguese river basins using both morphological characters and heart tissue fatty acid signature. In both cases, the multiple discriminant analysis revealed statistically significant differences among groups, and the overall corrected classification rate estimated from cross-validation procedure was particularly high for the cardiac muscle fatty acid profiles (i.e. 83.8%). Morphometric characters were much more useful than meristic ones to discriminate stocks, and the most important variables for group differentiation were eye length, second dorsal fin length and branchial length. Fatty acid analysis showed that all lampreys from the southern Guadiana group were correctly classified and not mixing with individuals from any other group, reflecting a typical heart fatty acid signature. Our results revealed that 89.5% and 72.2% of the individuals from the Tagus and North/Central groups, respectively, were also correctly classified, despite some degree of overlap between individuals from these groups. The fatty acids that contributed to the observed segregation were C16:0; C17:0; C18:1ω9; C20:3ω6 and C22:2ω6. Detected differences are probably related with environmental variables to which lampreys may have been exposed, which leaded to different patterns of gene expression. These results suggest the existence of three different sea lamprey stocks in Portugal, with implication in terms of management and conservation. PMID:25259723

  9. Hybridization between previously isolated ancestors may explain the persistence of exactly two ancient lineages in the genome of the oyster parasite Perkinsus marinus.

    PubMed

    Thompson, Peter C; Rosenthal, Benjamin M; Hare, Matthew P

    2014-06-01

    Theory predicts that neutral genetic variation accumulates within populations to a level determined by gains through mutation and losses by genetic drift. This balance results in a characteristic distribution of allelic variation with the maximum allelic difference determined by effective population size. Here, we report a striking departure from these expectations in the form of allelic dimorphism, observed at the majority of seven loci examined in Perkinsus marinus, an important oyster parasite that causes Dermo disease. DNA sequences were collected from five loci flanking microsatellite repeats and two loci coding for superoxide dismutase enzymes that may mediate the parasite's interaction with its host. Based on 474 sequences, sampled across 5000 km of the eastern United States coastline, no more than two alleles were observed at each locus (discounting singletons). Depending on the locus, the common allele ranged in overall frequency from 72% to 92%. At each locus the two alleles differed substantially (3.8% sequence difference, on average), and the among-locus variance in divergences was not sufficient to reject a simultaneous origin for all dimorphisms using approximate Bayesian methods. Dimorphic alleles were estimated to have diverged from a common ancestral allele at least 0.9 million years ago. Across these seven loci, only five other alleles were ever observed, always as singletons and differing from the dimorphic alleles by no more than two nucleotides. Free recombination could potentially have shuffled these dimorphisms into as many as 243 multilocus combinations, but the existence of only ten combinations among all samples strongly supports low recombination frequencies and is consistent with the observed absence of intragenic recombination. We consider several demographic and evolutionary hypotheses to explain these patterns. Few can be conclusively rejected with the present data, but we advance a recent hybridization of ancient divergent lineages

  10. The Relationship Between Increasing Sea-surface Temperature and the Northward Spread of Perkinsus marinus(Dermo) Disease Epizootics in Oysters

    NASA Astrophysics Data System (ADS)

    Cook, T.; Folli, M.; Klinck, J.; Ford, S.; Miller, J.

    1998-04-01

    From its initial discovery in the Gulf of Mexico in the late 1940s until 1990,Perkinsus marinus, the parasite responsible for Dermo disease in the eastern oyster,Crassostrea virginica, was rarely found north of Chesapeake Bay. In 1990-92, an apparent range extension of the parasite led to epizootic outbreaks of the disease over a 500 km range north of Chesapeake Bay. One of the hypotheses for the range extension argues that small, undetected numbers of parasites were already present in northern oysters as the result of repeated historical introductions, and that a sharp warming trend in 1990-92 stimulated the disease outbreak. This argument was based on trends in air temperature. The present study examined this hypothesis by analysing water temperatures, rather than air temperatures, for five stations located in areas affected by the recent epizootics. At all five stations, there was a strong increasing trend in winter sea-surface temperature (SST) between 1986 and 1991. At four of the five stations, there was a smaller increasing trend in winter temperatures after 1960. There were no consistent or obvious trends in summer (August) temperatures. In Delaware Bay, which has a 40 year history of monitoring for oyster diseases, occasional findings ofP. marinusin oysters were correlated with warming episodes that were especially notable in the winter (February) record. Empirical orthogonal function (EOF) analysis showed that winter temperatures varied consistently at the stations examined and were associated with variations inP. marinusprevalence. Associations using EOF analysis with August temperatures were much weaker. The SST record is consistent with the hypothesis that increasing winter water temperatures have been important in the recent outbreak ofP. marinusepizootics in the north-eastern U.S.A.

  11. Biology of larval and metamorphosing sea lampreys, Petromyzon marinus, of the 1960 year class in the Big Garlic River, Michigan, Part II, 1966-72

    USGS Publications Warehouse

    Manion, Patrick J.; Smith, Bernard R.

    1978-01-01

    The 1960 year class of sea lampreys, Petromyzon marinus, isolated in a tributary of southern Lake Superior continued to yield information on the early life history of the sea lamprey. The larval population persisted and newly metamorphosed individuals were captured from 1966 until the study was terminated in 1972. The average lengths of larvae collected in October (when yearly growth is nearly complete) in successive years from 1966 to 1972 were 111, 113, 112, 114, 121, 128, and 129 mm. The average lengths of transforming lampreys during the same years were 150, 151, 145, 143, 144, 148, and 156 mm. A gradual downstream shift of the population took place. Catches in an inclined-plane trap at the lower end of the study area increased to a peak of 13,244 in the 1968-69 migration year (September 1-August 31), and then steadily decreased. As the number of lampreys decreased in the upper sections and increased in the lower ones, the changes in density were reflected in changes in growth rates. Although the mean length of ammocetes throughout the stream was 111 mm in 1966, it had increased by 1971 to 151 and 143 mm in the upstream sections (IV and V), but to only 115 mm in the densely populated area immediately above the trap. Of a total of 9,889 larvae marked in 1962-68 to study movement and distribution, 2,045 were recovered as larvae and 1,396 as newly transformed adults. Major downstream movements of larvae occurred during high water in April and May, and of transformed lampreys in mid-October through November. Each year about 40% (range, 30-68) of the annual production of transformed lampreys migrated from the Big Garlic River system in one 12-hour period, and 82% by the end of October. The Big Garlic River study proved conclusively that metamorphosis of a single year class occurs over a considerable number of years. Newly metamorphosed individuals were captured in almost steadily increasing numbers from 1965 (age V) to the termination of the study in 1972 (age XII

  12. Enhanced recovery of Arcobacter spp. using NaCl in culture media and re-assessment of the traits of Arcobacter marinus and Arcobacter halophilus isolated from marine water and shellfish.

    PubMed

    Salas-Massó, Nuria; Andree, Karl B; Furones, M Dolors; Figueras, M José

    2016-10-01

    The genus Arcobacter is a relatively poorly known group of bacteria, and the number of new species and sequences from non-culturable strains has increased considerably in recent years. This study investigates whether using media that contain NaCl might help to improve the recovery of Arcobacter spp. from marine environments. To this aim, 62 water and shellfish samples were analysed in parallel, with both a commonly used culture method (enrichment in Arcobacter-CAT broth followed by culture on Blood Agar) and a new one that supplements the Arcobacter-CAT enrichment broth with 2.5% NaCl (w/v) followed by culturing on Marine Agar. The new method yielded ca. 40% more positive samples and provided a higher diversity of known (11 vs. 7) and unknown (7 vs. 2) Arcobacter species. Among the 11 known species recovered, Arcobacter marinus and Arcobacter halophilus were isolated only by this new method. No more strains of these species have been isolated since their original descriptions, both of which were based only on a single strain. In view of that, the phenotypic characteristics of these species are re-evaluated in the present study, using the new strains. Strains of A. halophilus had the same phenotypic profile as the type strain. However, some strains of A. marinus differed from the type strain in that they did not hydrolyse indoxyl-acetate, becoming, therefore, the first Arcobacter species to show a varying ability to hydrolyse indoxyl-acetate. This study shows to what extent a simple variation to the culture media can have a big influence on positive samples and on the community of species recovered. PMID:27282494

  13. Failure of ATP supply to match ATP demand: the mechanism of toxicity of the lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), used to control sea lamprey (Petromyzon marinus) populations in the Great Lakes.

    PubMed

    Birceanu, Oana; McClelland, Grant B; Wang, Yuxiang S; Wilkie, Michael P

    2009-10-01

    Although the pesticide, 3-trifluoromethyl-4-nitrophenol (TFM), has been extensively used to control invasive sea lamprey (Petromyzon marinus) populations in the Great Lakes, it is surprising that its mechanism(s) of toxicity is unresolved. A better knowledge of the mode of toxicity of this pesticide is needed for predicting and improving the effectiveness of TFM treatments on lamprey, and for risk assessments regarding potential adverse effects on invertebrate and vertebrate non-target organisms. We investigated two hypotheses of TFM toxicity in larval sea lamprey. The first was that TFM interferes with oxidative ATP production by mitochondria, causing rapid depletion of energy stores in vital, metabolically active tissues such as the liver and brain. The second was that TFM toxicity resulted from disruption of gill-ion uptake, adversely affecting ion homeostasis. Exposure of larval sea lamprey to 4.6 m gl(-1) TFM (12-h LC50) caused glycogen concentrations in the brain to decrease by 80% after 12h, suggesting that the animals increased their reliance on glycolysis to generate ATP due to a shortfall in ATP supply. This conclusion was reinforced by a 9-fold increase in brain lactate concentration, a 30% decrease in brain ATP concentration, and an 80% decrease in phosphocreatine (PCr) concentration after 9 and 12h. A more pronounced trend was noted in the liver, where glycogen decreased by 85% and ATP was no longer detected after 9 and 12h. TFM led to marginal changes in whole body Na(+), Cl(-), Ca(2+) and K(+), as well as in plasma Na(+) and Cl(-), which were unlikely to have contributed to toxicity. TFM had no adverse effect on Na(+) uptake rates or gill Na(+)/K(+)-ATPase activity. We conclude that TFM toxicity in the sea lamprey is due to a mismatch between ATP consumption and ATP production rates, leading to a depletion of glycogen in the liver and brain, which ultimately leads to neural arrest and death. PMID:19716611

  14. Immunolocalization and mRNA expression of the epithelial Na+ channel alpha-subunit in the kidney and urinary bladder of the marine toad, Bufo marinus, under hyperosmotic conditions.

    PubMed

    Konno, Norifumi; Hyodo, Susumu; Yamada, Toshiki; Matsuda, Kouhei; Uchiyama, Minoru

    2007-06-01

    The amiloride-sensitive epithelial sodium channel (ENaC) has previously been shown to be involved in the maintenance of body fluid volume and in Na(+) absorption across the skin and urinary bladder in amphibians. However, the function and distribution of ENaC have not been clearly described in amphibian kidney. We therefore cloned the ENaC alpha-subunit cDNA from kidney of the marine toad, Bufo marinus. The ENaC mRNA and protein were abundantly expressed in the kidney and in the urinary bladder and ventral pelvic skin. In an immunohistochemical study, the ENaC alpha-subunit protein was specifically localized to the apical membrane of the principal cells but not the intercalated cells from the late distal tubule to the collecting duct in the kidney or in the apical area of cells of urinary bladder epithelia. When toads were acclimated to dry and hyper-saline environments, the levels of ENaC mRNA expression in the kidney and urinary bladder decreased under hyper-saline acclimation, but not under dry conditions. Immunohistochemical observations indicated that the levels of ENaC protein expression were much lower in the apical area of renal distal tubules and urinary bladder epithelia of hyper-saline acclimated toad compared with controls. The present study suggests that Bufo ENaC is significantly expressed and functions during Na(+) reabsorption in the apical membrane domain in the distal nephron of normal and desiccated toads. Natriuresis may be caused by decreases in ENaC expression and its trafficking to the cell surface in the distal nephron, a response to prevent excessive Na(+) reabsorption in hyper-saline-acclimated toads. PMID:17333031

  15. Proteogenomic Analysis of a Thermophilic Bacterial Consortium Adapted to Deconstruct Switchgrass

    PubMed Central

    D'haeseleer, Patrik; Gladden, John M.; Allgaier, Martin; Chain, Patrik S. G.; Tringe, Susannah G.; Malfatti, Stephanie A.; Aldrich, Joshua T.; Nicora, Carrie D.; Robinson, Errol W.; Paša-Tolić, Ljiljana; Hugenholtz, Philip; Simmons, Blake A.; Singer, Steven W.

    2013-01-01

    Thermophilic bacteria are a potential source of enzymes for the deconstruction of lignocellulosic biomass. However, the complement of proteins used to deconstruct biomass and the specific roles of different microbial groups in thermophilic biomass deconstruction are not well-explored. Here we report on the metagenomic and proteogenomic analyses of a compost-derived bacterial consortium adapted to switchgrass at elevated temperature with high levels of glycoside hydrolase activities. Near-complete genomes were reconstructed for the most abundant populations, which included composite genomes for populations closely related to sequenced strains of Thermus thermophilus and Rhodothermus marinus, and for novel populations that are related to thermophilic Paenibacilli and an uncultivated subdivision of the little-studied Gemmatimonadetes phylum. Partial genomes were also reconstructed for a number of lower abundance thermophilic Chloroflexi populations. Identification of genes for lignocellulose processing and metabolic reconstructions suggested Rhodothermus, Paenibacillus and Gemmatimonadetes as key groups for deconstructing biomass, and Thermus as a group that may primarily metabolize low molecular weight compounds. Mass spectrometry-based proteomic analysis of the consortium was used to identify >3000 proteins in fractionated samples from the cultures, and confirmed the importance of Paenibacillus and Gemmatimonadetes to biomass deconstruction. These studies also indicate that there are unexplored proteins with important roles in bacterial lignocellulose deconstruction. PMID:23894306

  16. Proteogenomic Analysis of a Thermophilic Bacterial Consortium Adapted to Deconstruct Switchgrass

    SciTech Connect

    D'haeseleer, Patrik; Gladden, John M.; Allgaier, Martin; Chain, Patrick; Tringe, Susannah G.; Malfatti, Stephanie; Aldrich, Joshua T.; Nicora, Carrie D.; Robinson, Errol W.; Pasa-Tolic, Ljiljana; Hugenholtz, Philip; Simmons, Blake A.; Singer, Steven W.

    2013-07-19

    Thermophilic bacteria are a potential source of enzymes for the deconstruction of lignocellulosic biomass. However, the complement of proteins used to deconstruct biomass and the specific roles of different microbial groups in thermophilic biomass deconstruction are not well-explored. Here we report on the metagenomic and proteogenomic analyses of a compost-derived bacterial consortium adapted to switchgrass at elevated temperature with high levels of glycoside hydrolase activities. Near-complete genomes were reconstructed for the most abundant populations, which included composite genomes for populations closely related to sequenced strains of Thermus thermophilus and Rhodothermus marinus, and for novel populations that are related to thermophilic Paenibacilli and an uncultivated subdivision of the littlestudied Gemmatimonadetes phylum. Partial genomes were also reconstructed for a number of lower abundance thermophilic Chloroflexi populations. Identification of genes for lignocellulose processing and metabolic reconstructions suggested Rhodothermus, Paenibacillus and Gemmatimonadetes as key groups for deconstructing biomass, and Thermus as a group that may primarily metabolize low molecular weight compounds. Mass spectrometry-based proteomic analysis of the consortium was used to identify .3000 proteins in fractionated samples from the cultures, and confirmed the importance of Paenibacillus and Gemmatimonadetes to biomass deconstruction. These studies also indicate that there are unexplored proteins with important roles in bacterial lignocellulose deconstruction.

  17. Reconstitution of respiratory complex I on a biomimetic membrane supported on gold electrodes.

    PubMed

    Gutiérrez-Sanz, Oscar; Olea, David; Pita, Marcos; Batista, Ana P; Alonso, Alvaro; Pereira, Manuela M; Vélez, Marisela; De Lacey, Antonio L

    2014-07-29

    For the first time, respiratory complex I has been reconstituted on an electrode preserving its structure and activity. Respiratory complex I is a membrane-bound enzyme that has an essential function in cellular energy production. It couples NADH:quinone oxidoreduction to translocation of ions across the cellular (in prokaryotes) or mitochondrial membranes. Therefore, complex I contributes to the establishment and maintenance of the transmembrane difference of electrochemical potential required for adenosine triphosphate synthesis, transport, and motility. Our new strategy has been applied for reconstituting the bacterial complex I from Rhodothermus marinus onto a biomimetic membrane supported on gold electrodes modified with a thiol self-assembled monolayer (SAM). Atomic force microscopy and faradaic impedance measurements give evidence of the biomimetic construction, whereas electrochemical measurements show its functionality. Both electron transfer and proton translocation by respiratory complex I were monitored, simulating in vivo conditions. PMID:24988043

  18. Genome sequence of a native-feather degrading extremely thermophilic Eubacterium, Fervidobacterium islandicum AW-1.

    PubMed

    Lee, Yong-Jik; Jeong, Haeyoung; Park, Gun-Seok; Kwak, Yunyoung; Lee, Sang-Jae; Lee, Sang Jun; Park, Min-Kyu; Kim, Ji-Yeon; Kang, Hwan Ku; Shin, Jae-Ho; Lee, Dong-Woo

    2015-01-01

    Fervidobacterium islandicum AW-1 (KCTC 4680) is an extremely thermophilic anaerobe isolated from a hot spring in Indonesia. This bacterium could degrade native chicken feathers completely at 70 °C within 48 h, which is of potential importance on the basis of relevant environmental and agricultural issues in bioremediation and development of eco-friendly bioprocesses for the treatment of native feathers. However, its genomic and phylogenetic analysis remains unclear. Here, we report the high-quality draft genome sequence of an extremely thermophilic anaerobe, F. islandicum AW-1. The genome consists of 2,359,755 bp, which encodes 2,184 protein-coding genes and 64 RNA-encoding genes. This may reveal insights into anaerobic metabolism for keratin degradation and also provide a biological option for poultry waste treatments. PMID:26421103

  19. High resolution structure of the large ribosomal subunit from a Mesophilic Eubacterium

    SciTech Connect

    Harms, Joerg; Schluenzen, Frank; Zarivach, Raz; Bashan, Anat; Gat, Sharon; Agmon, Ilana; Bartels, Heike; Franceschi, Francois; Yonath, Ada

    2009-10-07

    We describe the high resolution structure of the large ribosomal subunit from Deinococcus radiodurans (D50S), a gram-positive mesophile suitable for binding of antibiotics and functionally relevant ligands. The over-all structure of D50S is similar to that from the archae bacterium Haloarcula marismortui (H50S); however, a detailed comparison revealed significant differences, for example, in the orientation of nucleotides in peptidyl transferase center and in the structures of many ribosomal proteins. Analysis of ribosomal features involved in dynamic aspects of protein biosynthesis that are partially or fully disordered in H50S revealed the conformations of intersubunit bridges in unbound subunits, suggesting how they may change upon subunit association and how movements of the L1-stalk may facilitate the exit of tRNA.

  20. Rearing of sea lamprey, Petromyzon marinus, embryos in distilled water

    USGS Publications Warehouse

    Piavis, George W.; Howell, John H.

    1969-01-01

    Most embryological studies of lampreys in the Great Lakes have been conducted with filtered water from Lake Huron. Although this water was entirely satisfactory for the earlier work, the present need for knowledge of the effects of various compounds on embryological development requires that the initial medium be sterile. The purpose of the present study was to determine whether sea lamprey embryos could be successfully reared in distilled water. Mature sea lampreys were collected from the Ocqueoc River, Presque Isle County, Michigan, and transferred to the Hammond Bay Biological Station where eggs were stripped and fertilized according to the method of Piavis. After activation was ascertained to be 90-100% complete, the embryos were washed 3-5 timesexperimentals with commercially obtained U.S.P. distilled water and controls with filtered Lake Huron water.

  1. Metamorphosis of the landlocked sea lamprey, Petromyzon marinus

    USGS Publications Warehouse

    Manion, Patrick J.; Stauffer, Thomas M.

    1970-01-01

    The external metamorphosis of the sea lamprey was divided into four stages, based primarily on the condition of the mouth: mouth reduced, mouth fused, mouth enclosed, and mouth elongated. During metamorphosis, the eye enlarged greatly, the snout and mouth region changed from a fleshy hood enclosing a sieve apparatus to a large sucking disc, the nasopore membrane and the branchial area shrank, the branchiopores changed in shape, the general color changed from dark brown and yellow to an intense blue-black dorsally and white ventrally, and the total length increased. Metamorphosis began in early to mid-July and did not take place after August. The duration of external metamorphosis was about 3 months for lampreys transforming under natural conditions. The mean lengths of metamorphosing lampreys from tributaries of lakes Superior and Michigan were 145 and 136 mm, respectively.

  2. The structural basis of substrate promiscuity in UDP-hexose 4-epimerase from the hyperthermophilic Eubacterium Thermotoga maritima.

    PubMed

    Shin, Sun-Mi; Choi, Jin Myung; di Luccio, Eric; Lee, Yong-Jik; Lee, Sang-Jae; Lee, Sang Jun; Lee, Sung Haeng; Lee, Dong-Woo

    2015-11-01

    UDP-galactose 4-epimerase (GalE) catalyzes the interconversion of UDP-glucose (UDP-Glc) and UDP-galactose (UDP-Gal), which is a pivotal step in the Leloir pathway for d-galactose metabolism. Although GalE is widely distributed in prokaryotes and eukaryotes, little information is available regarding hyperthermophilic GalE. We overexpressed the TM0509 gene, encoding a putative GalE from Thermotoga maritima (TMGalE), in Escherichia coli and characterized the encoded protein. To further investigate the molecular basis of this enzyme's catalytic function, we determined the crystal structures of TMGalE and TMGalE bound to UDP-Glc at resolutions of 1.9 Å and 2.0 Å, respectively. The enzyme was determined to be a homodimer with a molecular mass of 70 kDa. The enzyme could reversibly catalyze the epimerization of UDP-GalNAc/UDP-GlcNAc as well as UDP-Gal/UDP-Glc at elevated temperatures, with an apparent optimal temperature and pH of 80 °C and 7.0, respectively. Our data showed that TM0509 is a UDP-galactosugar 4-epimerase involved in d-galactose metabolism; consequently, this study provides the first detailed characterization of a hyperthermophilic GalE. Moreover, the promiscuous substrate specificity of TMGalE, which is more similar to human GalE than E. coli GalE, supports the notion that TMGalE might exhibit the earliest form of sugar-epimerizing enzymes in the evolution of galactose metabolism. PMID:26344854

  3. A carbohydrate binding module as a diversity-carrying scaffold.

    PubMed

    Cicortas Gunnarsson, L; Nordberg Karlsson, E; Albrekt, A-S; Andersson, M; Holst, O; Ohlin, M

    2004-03-01

    The growing field of biotechnology is in constant need of binding proteins with novel properties. Not just binding specificities and affinities but also structural stability and productivity are important characteristics for the purpose of large-scale applications. In order to find such molecules, libraries are created by diversifying naturally occurring binding proteins, which in those cases serve as scaffolds. In this study, we investigated the use of a thermostable carbohydrate binding module, CBM4-2, from a xylanase found in Rhodothermus marinus, as a diversity-carrying scaffold. A combinatorial library was created by introducing restricted variation at 12 positions in the carbohydrate binding site of the CBM4-2. Despite the small size of the library (1.6 x 10(6) clones), variants specific towards different carbohydrate polymers (birchwood xylan, Avicel and ivory nut mannan) as well as a glycoprotein (human IgG4) were successfully selected for, using the phage display method. Investigated clones showed a high productivity (on average 69 mg of purified protein/l shake flask culture) when produced in Escherichia coli and they were all stable molecules displaying a high melting transition temperature (75.7 +/- 5.3 degrees C). All our results demonstrate that the CBM4-2 molecule is a suitable scaffold for creating variants useful in different biotechnological applications. PMID:15082834

  4. Community dynamics and glycoside hydrolase activities of thermophilic bacterial consortia adapted to switchgrass

    SciTech Connect

    Gladden, J.M.; Allgaier, M.; Miller, C.S.; Hazen, T.C.; VanderGheynst, J.S.; Hugenholtz, P.; Simmons, B.A.; Singer, S.W.

    2011-05-01

    Industrial-scale biofuel production requires robust enzymatic cocktails to produce fermentable sugars from lignocellulosic biomass. Thermophilic bacterial consortia are a potential source of cellulases and hemicellulases adapted to harsher reaction conditions than commercial fungal enzymes. Compost-derived microbial consortia were adapted to switchgrass at 60 C to develop thermophilic biomass-degrading consortia for detailed studies. Microbial community analysis using small-subunit rRNA gene amplicon pyrosequencing and short-read metagenomic sequencing demonstrated that thermophilic adaptation to switchgrass resulted in low-diversity bacterial consortia with a high abundance of bacteria related to thermophilic paenibacilli, Rhodothermus marinus, and Thermus thermophilus. At lower abundance, thermophilic Chloroflexi and an uncultivated lineage of the Gemmatimonadetes phylum were observed. Supernatants isolated from these consortia had high levels of xylanase and endoglucanase activities. Compared to commercial enzyme preparations, the endoglucanase enzymes had a higher thermotolerance and were more stable in the presence of 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]), an ionic liquid used for biomass pretreatment. The supernatants were used to saccharify [C2mim][OAc]-pretreated switchgrass at elevated temperatures (up to 80 C), demonstrating that these consortia are an excellent source of enzymes for the development of enzymatic cocktails tailored to more extreme reaction conditions.

  5. Crystallization, neutron data collection, initial structure refinement and analysis of a xyloglucan heptamer bound to an engineered carbohydrate-binding module from xylanase.

    PubMed

    Ohlin, Mats; von Schantz, Laura; Schrader, Tobias E; Ostermann, Andreas; Logan, Derek T; Fisher, S Zoë

    2015-08-01

    Carbohydrate-binding modules (CBMs) are discrete parts of carbohydrate-hydrolyzing enzymes that bind specific types of carbohydrates. Ultra high-resolution X-ray crystallographic studies of CBMs have helped to decipher the basis for specificity in carbohydrate-protein interactions. However, additional studies are needed to better understand which structural determinants confer which carbohydrate-binding properties. To address these issues, neutron crystallographic studies were initiated on one experimentally engineered CBM derived from a xylanase, X-2 L110F, a protein that is able to bind several different plant carbohydrates such as xylan, β-glucan and xyloglucan. This protein evolved from a CBM present in xylanase Xyn10A of Rhodothermus marinus. The protein was complexed with a branched xyloglucan heptasaccharide. Large single crystals of hydrogenous protein (∼1.6 mm(3)) were grown at room temperature and subjected to H/D exchange. Both neutron and X-ray diffraction data sets were collected to 1.6 Å resolution. Joint neutron and X-ray refinement using phenix.refine showed significant density for residues involved in carbohydrate binding and revealed the details of a hydrogen-bonded water network around the binding site. This is the first report of a neutron structure of a CBM and will add to the understanding of protein-carbohydrate binding interactions. PMID:26249702

  6. Structural and functional exchangeability of 5 S RNA species from the eubacterium E.coli and the thermoacidophilic archaebacterium Sulfolobus solfataricus.

    PubMed Central

    Teixidò, J; Altamura, S; Londei, P; Amils, R

    1989-01-01

    The role of 5 S RNA within the large ribosomal subunit of the extremely thermophilic archaebacterium Sulfolobus solfataricus has been analysed by means of in vitro reconstitution procedures. It is shown that Sulfolobus 50 S subunits reconstituted in the absence of 5 S RNA are inactive in protein synthesis and lack 2-3 ribosomal proteins. Furthermore, it has been determined that in the course of the in vitro assembly process Sulfolobus 5 S RNA can be replaced by the correspondent RNA species of E.coli; Sulfolobus reconstituted particles containing the eubacterial 5 S molecule are stable and active in polypeptide synthesis at high temperatures. Images PMID:2493632

  7. Beta-lactam biosynthesis in a gram-negative eubacterium: purification and characterization of isopenicillin N synthase from Flavobacterium sp. strain SC 12.154.

    PubMed Central

    Palissa, H; von Döhren, H; Kleinkauf, H; Ting, H H; Baldwin, J E

    1989-01-01

    The occurrence, localization, and extraction of isopenicillin N-synthase (IPNS) were investigated in the gram-negative low-level beta-lactam producer Flavobacterium sp. strain SC 12.154, which forms deacetoxycephalosporin and excretes the cephabacin 7-formamidocephalosporin. IPNS was detected with anti-IPNS antibodies raised against the Cephalosporium acremonium enzyme. The flavobacterium enzyme, whose molecular mass (38 kilodaltons) and cofactor requirements resemble those of the fungal and Streptomyces enzymes, is formed at the transition from growth to the stationary phase. It was extracted into the polyethylene glycol phase of a polyethylene glycol-Ficoll-dextran three-phase system and was purified by quaternary aminoethyl ion-exchange chromatography, gel filtration, covalent chromatography on cystamine-Sepharose, and fast-protein liquid chromatography on Mono Q. The enzyme was characterized with respect to sulfhydryl requirement, inhibition by disulfides and metal ions, pH and temperature dependence, and stimulation by polyethylene glycol and low Triton X-100 concentrations, as well as by several amino acids, including alpha-aminoadipic acid and cysteine. The Km for alpha-aminoadipyl-cysteinyl-D-valine was 0.08 mM. An inactive membrane-associated form of IPNS was detected together with a beta-lactamase active on isopenicillin N. The system has been suggested as a model for the study of endogenous functions of beta-lactams in bacteria. Images PMID:2793834

  8. Structural insights into the epimerization of β-1,4-linked oligosaccharides catalyzed by cellobiose 2-epimerase, the sole enzyme epimerizing non-anomeric hydroxyl groups of unmodified sugars.

    PubMed

    Fujiwara, Takaaki; Saburi, Wataru; Matsui, Hirokazu; Mori, Haruhide; Yao, Min

    2014-02-01

    Cellobiose 2-epimerase (CE) reversibly converts d-glucose residues into d-mannose residues at the reducing end of unmodified β1,4-linked oligosaccharides, including β-1,4-mannobiose, cellobiose, and lactose. CE is responsible for conversion of β1,4-mannobiose to 4-O-β-d-mannosyl-d-glucose in mannan metabolism. However, the detailed catalytic mechanism of CE is unclear due to the lack of structural data in complex with ligands. We determined the crystal structures of halothermophile Rhodothermus marinus CE (RmCE) in complex with substrates/products or intermediate analogs, and its apo form. The structures in complex with the substrates/products indicated that the residues in the β5-β6 loop as well as those in the inner six helices form the catalytic site. Trp-322 and Trp-385 interact with reducing and non-reducing end parts of these ligands, respectively, by stacking interactions. The architecture of the catalytic site also provided insights into the mechanism of reversible epimerization. His-259 abstracts the H2 proton of the d-mannose residue at the reducing end, and consistently forms the cis-enediol intermediate by facilitated depolarization of the 2-OH group mediated by hydrogen bonding interaction with His-200. His-390 subsequently donates the proton to the C2 atom of the intermediate to form a d-glucose residue. The reverse reaction is mediated by these three histidines with the inverse roles of acid/base catalysts. The conformation of cellobiitol demonstrated that the deprotonation/reprotonation step is coupled with rotation of the C2-C3 bond of the open form of the ligand. Moreover, it is postulated that His-390 is closely related to ring opening/closure by transferring a proton between the O5 and O1 atoms of the ligand. PMID:24362032

  9. An anti-steroidogenic inhibitory primer pheromone in male sea lamprey (Petromyzon marinus)

    USGS Publications Warehouse

    Chung-Davidson, Yu-Wen; Wang, Huiyong; Bryan, Mara B.; Wu, Hong; Johnson, Nicholas S.; Li, Weiming

    2013-01-01

    Reproductive functions can be modulated by both stimulatory and inhibitory primer pheromones released by conspecifics. Many stimulatory primer pheromones have been documented, but relatively few inhibitory primer pheromones have been reported in vertebrates. The sea lamprey male sex pheromone system presents an advantageous model to explore the stimulatory and inhibitory primer pheromone functions in vertebrates since several pheromone components have been identified. We hypothesized that a candidate sex pheromone component, 7α, 12α-dihydroxy-5α-cholan-3-one-24-oic acid (3 keto-allocholic acid or 3kACA), exerts priming effects through the hypothalamic-pituitary-gonadal (HPG) axis. To test this hypothesis, we measured the peptide concentrations and gene expressions of lamprey gonadotropin releasing hormones (lGnRH) and the HPG output in immature male sea lamprey exposed to waterborne 3kACA. Exposure to waterborne 3kACA altered neuronal activation markers such as jun and jun N-terminal kinase (JNK), and lGnRH mRNA levels in the brain. Waterborne 3kACA also increased lGnRH-III, but not lGnRH-I or -II, in the forebrain. In the plasma, 3kACA exposure decreased all three lGnRH peptide concentrations after 1 h exposure. After 2 h exposure, 3kACA increased lGnRHI and -III, but decreased lGnRH-II peptide concentrations in the plasma. Plasma lGnRH peptide concentrations showed differential phasic patterns. Group housing condition appeared to increase the averaged plasma lGnRH levels in male sea lamprey compared to isolated males. Interestingly, 15α-hydroxyprogesterone (15α-P) concentrations decreased after prolonged 3kACA exposure (at least 24 h). To our knowledge, this is the only known synthetic vertebrate pheromone component that inhibits steroidogenesis in males.

  10. UPTAKE, DISTRIBUTION, AND BIOCONVERSION OF FLUORESCENT LIPID ANALOGS IN THE OYSTER PROTOZOAN PARASITE, PERKINSUS MARINUS

    EPA Science Inventory

    It has been established that host lipids play a unique role for long term survival and life cycle completion in endogenous parasites. Parasites exploit fatty acids and lipids from the host, not only for membrane synthesis, but also for modification of their surface integrity to a...

  11. Flapping flexible fish. Periodic and secular body reconfigurations in swimming lamprey, Petromyzon marinus

    NASA Astrophysics Data System (ADS)

    Root, Robert G.; Courtland, Hayden-William; Shepherd, William; Long, John H.

    2007-11-01

    In order to analyze and model the body kinematics used by fish in a wide range of swimming behaviors, we developed a technique to separate the periodic whole-body motions that characterize steady swimming from the secular motions that characterize changes in whole-body shape. We applied this harmonic analysis technique to the study of the forward and backward swimming of lamprey. We found that in order to vary the unsteadiness of swimming, lamprey superimpose periodic and secular components of their body motion, modulate the patterns and magnitudes of those components, and change shape. These kinematic results suggest the following hydromechanical hypothesis: steady swimming is a maneuver that requires active suppression of secular body reconfigurations.

  12. Diseases and parasites of the sea lamprey, Petromyzon marinus, in the Lake Huron basin

    USGS Publications Warehouse

    McLain, Alberton L.

    1952-01-01

    Sea lampreys from the Lake Huron basin carried no external parasites and showed a fairly low degree of infection by internal parasites. The material examined represented three life-history stages of the sea lamprey. Recently transformed downstream migrants (215 specimens) harbored only nematodes belonging to the genus Camallanus. The percentage of infection was 2.3. Active feeders from the lake (29 lampreys) revealed the highest degree of parasitism (31.0 percent) with the following parasites present: Echinorhynchus coregoni Linkins; Triaenophorus crassus Forel; and Camallanus sp. Among the 257 sexually mature upstream migrants (14.8 percent infected) Echinorhynchus coregoni and E. leidyi Van Cleave were the most common. Only occasional nematodes and cestodes were found, which fact indicates a failure of the lamprey to carry these parasites to the end of its natural life. Of the parasites observed, only the nematodes gave evidence of serious damage to the host. The study suggests that the role played by parasites in the natural control of the sea lamprey in its new habitat in the upper Great Lakes is of minor importance.

  13. Phycobiliproteins in Prochlorococcus marinus: biosynthesis of pigments and their assembly into proteins.

    PubMed

    Wiethaus, Jessica; Busch, Andrea W U; Dammeyer, Thorben; Frankenberg-Dinkel, Nicole

    2010-12-01

    Prochlorococcus sp. is a very unique and highly abundant class of organisms within the cyanobacteria. Found in the world's oceans Prochlorococcus is very small in size and possesses the smallest genome of a photosynthetic autotroph. Prochlorococcus is characterized by a special chlorophyll antenna for light harvesting and the absence of classical cyanobacterial phycobilisomes. Despite the lack of phycobilisomes Prochlorococcus possesses remnants thereof which is the phycobiliprotein phycoerythrin (PE) encoded in a PE operon as well as genes encoding enzymes of phycobilin biosynthesis. The size of this PE operon varies depending on the light-adapted ecotype. While high-light strains only possess a β-subunit of PE, low-light adapted strains possess both, an α- and a β-subunit. α-/β-subunits are also present in functional phycobilisomes. Consistent with the number of subunits is also the varying number of putative lyase genes, involved in the transfer and attachment of phycobilins (open-chain tetrapyrroles) to the PE subunits. This minireview summarizes the only sparely available data on the biosynthesis and assembly of Prochlorococcus PE. On one hand the quite well understood biosynthesis of pigments will be reviewed but also new data on the phycobiliprotein lyase-mediated transfer of the phycobilins to the PE subunits will be discussed. PMID:20724022

  14. Control of the sea lamprey (Petromyzon marinus) in Lake Superior, 1953-70

    USGS Publications Warehouse

    Smith, Bernard R.; Tibbles, J. James; Johnson, B.G.H.

    1974-01-01

    Although sea lamprey control and heavy plantings of hatchery-reared stock had restored lake trout abundance to prelamprey levels in many areas by 1970, the trout had not yet become self-sustaining. Additional effort will be required to further reduce the effects of lamprey predation.

  15. IN VITRO KILLING OF PERKINSUS MARINUS BY HEMOCYTES OF OYSTERS CRASSOSTREA VIRGINICA

    EPA Science Inventory

    Presented at the 92nd Annual Meeting of the National Shellfisheries Association, 19-23 March 2000, Seattle, WA.

    A colorimetric microbicidal assay was adapted, optimized and used in experiments to characterize the capacity of eastern oyster (Crassostrea virginica) hemocytes...

  16. Sex ratios and sexual dimorphism among recently transformed sea lampreys, Petromyzon marinus Linnaeus

    USGS Publications Warehouse

    Applegate, Vernon C.; Thomas, M.L.H.

    1965-01-01

    The sex, length, and weight were determined of nearly all recently transformed sea lampreys migrating downstream in the Carp Lake River, Michigan, in the fall, winter, and spring of 1960-61. Similar data were collected from samples of an earlier run in the Carp Lake River and of runs in three other tributaries of Lakes Huron and Michigan. The sex ratio of the 1960-61 migrants in the Carp Lake River was 324 males:100 females. Sex ratios of migrants in the other runs varied from 77 to 86 males:100 females. The high proportion of males in the 1960-61 run in the Carp Lake River is attributed to the effective prevention of recruitment of sea lampreys in the river and transformation of the females at an earlier age than is characteristic of the males. A near equal sex ratio among recently transformed migrants is considered normal for the species. The sex composition of a run changed during the period of migration. The proportion of males among the migrants was greatest at the beginning of the run and declined steadily thereafter. The average size was smaller for males than for females. Differences in the mean lengths and weights of the sexes were statistically significant. The length-weight relation differed for the sexes and showed a slower rate of increase of weight with increase in length than is characteristic of other stages of the animals' life cycle. Seasonal changes in the length-weight relation had a trend toward lower weights among the migrants coming downstream in the later months of the run.

  17. Downstream movement of recently transformed sea lampreys, Petromyzon marinus, in Carp Lake River, Michigan

    USGS Publications Warehouse

    Applegate, Vernon C.; Brynildson, Clifford L.

    1951-01-01

    A total of 7,969 downstream migrants were taken in the 1948–49 season; 16,235 in 1949–50, and 15,103 in 1950–51. Measurements of representative samples from the total catch of sea lamprey migrants of the 1948–49 and 1949–50 seasons revealed a range in length of 95 to 190 millimeters and an average length of 145 millimeters (3.7 to 7.5 inches; mean –5.7 inches).

  18. MODULATION OF EASTERN OYSTER HEMOCYTE ACTIVITIES BY PERKINSUS MARINUS EXTRACELLULAR PROTEINS

    EPA Science Inventory

    The oyster pathogen Perkinsus marinusproduces many extracellular proteins (ECP) in vitro. Analysis of this ECP revealed a battery of hydrolytic enzymes. Some of these enzymes are known to modulate the activity of host defense cells. Although information on the effects of P. marin...

  19. Effects of certain chemicals on mucus-producing cells of Petromyzon marinus

    USGS Publications Warehouse

    Sawyer, Philip J.

    1959-01-01

    Tissue samples that contained slime-secreting cells were taken from the gills and epidermis of larval lampreys that had been poisoned by several compounds. Histochemical treatment of these pathological tissues helped delineate the fate of these mucus-producing areas of the ammocetes. It was shown that the slime-secreting cells, located at the tips of the gill filaments, lining the gill chamber, and scattered throughout the epidermis reacted differently to the same toxicant. The secretory cells of the gills were, without exception, the most sensitive to chemical attack.

  20. Regulation of a putative corticosteroid, 17, 21-dihydroxypregn-4-ene, 3, 20-one, in sea lamprey, Petromyzon marinus.

    USGS Publications Warehouse

    Roberts, Brent W.; Didier, Wes; Satbir, Rai; Johnson, Nicholas S.; Libants, Scot V.; Sang-Seon, Yun; Close, David

    2013-01-01

    In higher vertebrates, in response to stress, the hypothalamus produces corticotropin-releasing hormone (CRH), which stimulates cells in the anterior pituitary to produce adrenocorticotropic hormone (ACTH), which in turn stimulates production of either cortisol (F) or corticosterone (B) by the adrenal tissues. In lampreys, however, neither of these steroids is present. Instead, it has been proposed that the stress steroid is actually 17,21-dihydroxypregn-4-ene-3,20-dione (11-deoxycortisol; S). However, there have been no studies yet to determine its mechanism of regulation or site of production. Here we demonstrate that (1) intraperitoneal injections of lamprey-CRH increase plasma S in a dose dependent manner, (2) intraperitoneal injections of four lamprey-specific ACTH peptides at 100 lg/kg, did not induce changes in plasma S concentrations in either males or females; (3) two lamprey-specific gonadotropin-releasing hormones (GnRH I and III) and arginine-vasotocin (AVT), all at single doses, stimulated S production as well as, or to an even greater extent than CRH; (4) sea lamprey mesonephric kidneys, in vitro, converted tritiated 17a-hydroxyprogesterone (17a-P) into a steroid that had the same chromatographic properties (on HPLC and TLC) as S; (5) kidney tissues released significantly more immunoassayable S into the incubation medium than gill, liver or gonad tissues. One interpretation of these results is that the corticosteroid production of the sea lamprey, one of the oldest extant vertebrates, is regulated through multiple pathways rather than the classical HPI-axis. However, the responsiveness of this steroid to the GnRH peptides means that a reproductive rather than a stress role for this steroid cannot yet be ruled out.

  1. Anatomy of the lamprey ear: morphological evidence for occurrence of horizontal semicircular ducts in the labyrinth of Petromyzon marinus

    USGS Publications Warehouse

    Maklad, Adel; Reed, Caitlyn; Johnson, Nicholas S.; Fritzsch, Bernd

    2014-01-01

    In jawed (gnathostome) vertebrates, the inner ears have three semicircular canals arranged orthogonally in the three Cartesian planes: one horizontal (lateral) and two vertical canals. They function as detectors for angular acceleration in their respective planes. Living jawless craniates, cyclostomes (hagfish and lamprey) and their fossil records seemingly lack a lateral horizontal canal. The jawless vertebrate hagfish inner ear is described as a torus or doughnut, having one vertical canal, and the jawless vertebrate lamprey having two. These observations on the anatomy of the cyclostome (jawless vertebrate) inner ear have been unchallenged for over a century, and the question of how these jawless vertebrates perceive angular acceleration in the yaw (horizontal) planes has remained open. To provide an answer to this open question we reevaluated the anatomy of the inner ear in the lamprey, using stereoscopic dissection and scanning electron microscopy. The present study reveals a novel observation: the lamprey has two horizontal semicircular ducts in each labyrinth. Furthermore, the horizontal ducts in the lamprey, in contrast to those of jawed vertebrates, are located on the medial surface in the labyrinth rather than on the lateral surface. Our data on the lamprey horizontal duct suggest that the appearance of the horizontal canal characteristic of gnathostomes (lateral) and lampreys (medial) are mutually exclusive and indicate a parallel evolution of both systems, one in cyclostomes and one in gnathostome ancestors.

  2. DECREASED RESISTANCE OF EASTERN OYSTERS (CRASSOSTREA VIRGINICA) TO A PROTOZOAN PATHOGEN (PERKINSUS MARINUS) AFTER SUBLETHAL EXPOSURE TO TRIBUTYLTIN OXIDE

    EPA Science Inventory

    Anthropogenic environmental stress is a likely contributor to outbreaks of disease due to immunosuppression or increased host vulnerability. Estuarine organisms are exposed to variable concentrations of marine antifouling agents, such as tributyltin (TBT), with higher exposures e...

  3. COMPARISON OF IN VITRO-CULTURED AND WILD-TYPE PERKINSUS MARINUS. II: DOSING METHODS AND HOST RESPONSE

    EPA Science Inventory

    Endoparasites must breach host barriers to establish infection and then must survive host internal defenses to cause disease. Such barriers may frustrate attempts to experimentally transmit parasites by ?natural' methods. In addition, the host's condition may affect a study's out...

  4. Sequence analysis of a complete 1.66 Mb Prochlorococcus marinus MED4 genome cloned in yeast

    PubMed Central

    Tagwerker, Christian; Dupont, Christopher L.; Karas, Bogumil J.; Ma, Li; Chuang, Ray-Yuan; Benders, Gwynedd A.; Ramon, Adi; Novotny, Mark; Montague, Michael G.; Venepally, Pratap; Brami, Daniel; Schwartz, Ariel; Andrews-Pfannkoch, Cynthia; Gibson, Daniel G.; Glass, John I.; Smith, Hamilton O.; Venter, J. Craig; Hutchison, Clyde A.

    2012-01-01

    Marine cyanobacteria of the genus Prochlorococcus represent numerically dominant photoautotrophs residing throughout the euphotic zones in the open oceans and are major contributors to the global carbon cycle. Prochlorococcus has remained a genetically intractable bacterium due to slow growth rates and low transformation efficiencies using standard techniques. Our recent successes in cloning and genetically engineering the AT-rich, 1.1 Mb Mycoplasma mycoides genome in yeast encouraged us to explore similar methods with Prochlorococcus. Prochlorococcus MED4 has an AT-rich genome, with a GC content of 30.8%, similar to that of Saccharomyces cerevisiae (38%), and contains abundant yeast replication origin consensus sites (ACS) evenly distributed around its 1.66 Mb genome. Unlike Mycoplasma cells, which use the UGA codon for tryptophane, Prochlorococcus uses the standard genetic code. Despite this, we observed no toxic effects of several partial and 15 whole Prochlorococcus MED4 genome clones in S. cerevisiae. Sequencing of a Prochlorococcus genome purified from yeast identified 14 single base pair missense mutations, one frameshift, one single base substitution to a stop codon and one dinucleotide transversion compared to the donor genomic DNA. We thus provide evidence of transformation, replication and maintenance of this 1.66 Mb intact bacterial genome in S. cerevisiae. PMID:22941652

  5. Ribosomal Oxygenases are Structurally Conserved from Prokaryotes to Humans

    PubMed Central

    Chowdhury, Rasheduzzaman; Krojer, Tobias; Ho, Chia-hua; Ng, Stanley S.; Clifton, Ian J.; Ge, Wei; Kershaw, Nadia J.; Fox, Gavin C.; Muniz, Joao R. C.; Vollmar, Melanie; Phillips, Claire; Pilka, Ewa S.; Kavanagh, Kathryn L.; von Delft, Frank; Oppermann, Udo; McDonough, Michael A.; Doherty, Aiden J.; Schofield, Christopher J.

    2014-01-01

    2-Oxoglutarate (2OG)-dependent oxygenases play important roles in the regulation of gene expression via demethylation of N-methylated chromatin components1,2, hydroxylation of transcription factors3, and of splicing factor proteins4. Recently, 2OG-oxygenases that catalyze hydroxylation of tRNA5-7 and ribosomal proteins8, have been shown to play roles in translation relating to cellular growth, TH17-cell differentiation and translational accuracy9-12. The finding that the ribosomal oxygenases (ROX) occur in organisms ranging from prokaryotes to humans8 raises questions as to their structural and evolutionary relationships. In Escherichia coli, ycfD catalyzes arginine-hydroxylation in the ribosomal protein L16; in humans, Mina53 (MYC-induced nuclear antigen) and NO66 (Nucleolar protein 66) catalyze histidine-hydroxylation in ribosomal proteins rpL27a and rpL8, respectively. The functional assignments of the ROX open therapeutic possibilities via either ROX inhibition or targeting of differentially modified ribosomes. Despite differences in residue- and protein-selectivities of prokaryotic and eukaryotic ROX, crystal structures of ycfD and ycfDRM from E. coli and Rhodothermus marinus with those of human Mina53 and NO66 (hROX) reveal highly conserved folds and novel dimerization modes defining a new structural subfamily of 2OG-oxygenases. ROX structures in complex with/without their substrates, support their functional assignments as hydroxylases, but not demethylases and reveal how the subfamily has evolved to catalyze the hydroxylation of different residue sidechains of ribosomal proteins. Comparison of ROX crystal structures with those of other JmjC-hydroxylases including the hypoxia-inducible factor asparaginyl-hydroxylase (FIH) and histone Nε-methyl lysine demethylases (KDMs) identifies branchpoints in 2OG-oxygenase evolution and distinguishes between JmjC-hydroxylases and -demethylases catalyzing modifications of translational and transcriptional machinery. The

  6. The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) uncouples mitochondrial oxidative phosphorylation in both sea lamprey (Petromyzon marinus) and TFM-tolerant rainbow trout (Oncorhynchus mykiss).

    PubMed

    Birceanu, Oana; McClelland, Grant B; Wang, Yuxiang S; Brown, Jason C L; Wilkie, Michael P

    2011-04-01

    The toxicity of 3-trifluoromethyl-4-nitrophenol (TFM) appears to be due to a mismatch between ATP supply and demand in lamprey, depleting glycogen stores and starving the nervous system of ATP. The cause of this TFM-induced ATP deficit is unclear. One possibility is that TFM uncouples mitochondrial oxidative phosphorylation, thus impairing ATP production. To test this hypothesis, mitochondria were isolated from the livers of sea lamprey and rainbow trout, and O(2) consumption rates were measured in the presence of TFM or 2,4-dinitrophenol (2,4-DNP), a known uncoupler of oxidative phosphorylation. TFM and 2,4-DNP markedly increased State IV respiration in a dose-dependent fashion, but had no effect on State III respiration, which is consistent with uncoupling of oxidative phosphorylation. To determine how TFM uncoupled oxidative phosphorylation, the mitochondrial transmembrane potential (TMP) was recorded using the mitochondria-specific dye rhodamine 123. Mitochondrial TMP decreased by 22% in sea lamprey, and by 28% in trout following treatment with 50μmolL(-1) TFM. These findings suggest that TFM acted as a protonophore, dissipating the proton motive force needed to drive ATP synthesis. We conclude that the mode of TFM toxicity in sea lamprey and rainbow trout is via uncoupling of oxidative phosphorylation, leading to impaired ATP production. PMID:21172453

  7. Biology of larval sea lampreys (Petromyzon marinus) of the 1960 year class, isolated in the Big Garlic River, Michigan, 1960-65

    USGS Publications Warehouse

    Manion, Patrick J.; McLain, Alberton L.

    1971-01-01

    The capture of four recently metamorphosed sea lampreys (two males and two females), 152-172 mm long, in the fall of 1965, established the minimum age at transformation for larvae in the Big Garlic River at 5 years. Age and length (with the exception of a possible minimum length) were determined not to be critical factors in metamorphosis. The presence of larvae 65-176 mm long (mean, 107 mm) in the river in 1965 indicated that metamorphosis of lampreys in a single year class takes place over a period of years.

  8. Structural lipid changes and Na(+)/K(+)-ATPase activity of gill cells' basolateral membranes during saltwater acclimation in sea lamprey (Petromyzon marinus, L.) juveniles.

    PubMed

    Lança, Maria João; Machado, Maria; Ferreira, Ana Filipa; Quintella, Bernardo Ruivo; de Almeida, Pedro Raposo

    2015-11-01

    Seawater acclimation is a critical period for anadromous species and a process yet to be understood in lampreys. Considering that changes in lipid composition of the gill cells' basolateral membranes may disrupt the major transporter Na(+)K(+)-ATPase, the goal of this study was to detect changes at this level during juvenile sea lamprey seawater acclimation. The results showed that saltwater acclimation has a direct effect on the fatty acid composition of gill cells basolateral membrane's phospholipids. When held in full-strength seawater, the fatty acid profile of basolateral membrane's phospholipids suffered a restructure by increasing either saturation or the ratio between oleic acid and eicosapentaenoic acid. Simultaneously, the activity of Na(+)K(+)-ATPase revealed a significant and positive correlation with basolateral membrane's cholesterol content in the presence of highest salinity. Our results pointed out for lipid adjustments involving the functional transporter present on the gill cell basolateral membranes to ensure the role played by branchial Na(+)K(+)-ATPase in ion transport during saltwater acclimation process. The responses observed contributed to the strategy adopted by gill cell's basolateral membranes to compensate for osmotic and ionic stressors, to ensure the success of the process of seawater acclimation associated with the downstream trophic migration of juvenile sea lamprey. PMID:26244517

  9. Ultra-performance liquid chromatography tandem mass spectrometry for simultaneous determination of natural steroid hormones in sea lamprey (Petromyzon marinus) plasma and tissues.

    PubMed

    Wang, Huiyong; Bussy, Ugo; Chung-Davidson, Yu-Wen; Li, Weiming

    2016-01-15

    This study aims to provide a rapid, sensitive and precise UPLC-MS/MS method for target steroid quantitation in biological matrices. We developed and validated an UPLC-MS/MS method to simultaneously determine 16 steroids in plasma and tissue samples. Ionization sources of Electrospray Ionization (ESI) and Atmospheric Pressure Chemical Ionization (APCI) were compared in this study by testing their spectrometry performances at the same chromatographic conditions, and the ESI source was found up to five times more sensitive than the APCI. Different sample preparation techniques were investigated for an optimal extraction of steroids from the biological matrices. The developed method exhibited excellent linearity for all analytes with regression coefficients higher than 0.99 in broad concentration ranges. The limit of detection (LOD) was from 0.003 to 0.1ng/mL. The method was validated according to FDA guidance and applied to determine steroids in sea lamprey plasma and tissues (fat and testes) by the developed method. PMID:26741990

  10. Hybridization between previously isolated ancestors may explain the persistence of exactly two ancient lineages in the genome of the oyster parasite Perkinsus marinus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Large biological populations that have not been subdivided should have accumulated variation in different genetic loci. Population samples should identify some loci lacking in variation, others characterized by a few alleles, and still others by many alleles. Departures from these expectations requi...

  11. Extensive frameshift at all AGG and CCC codons in the mitochondrial cytochrome c oxidase subunit 1 gene of Perkinsus marinus (Alveolata; Dinoflagellata)

    PubMed Central

    Masuda, Isao; Matsuzaki, Motomichi; Kita, Kiyoshi

    2010-01-01

    Diverse mitochondrial (mt) genetic systems have evolved independently of the more uniform nuclear system and often employ modified genetic codes. The organization and genetic system of dinoflagellate mt genomes are particularly unusual and remain an evolutionary enigma. We determined the sequence of full-length cytochrome c oxidase subunit 1 (cox1) mRNA of the earliest diverging dinoflagellate Perkinsus and show that this gene resides in the mt genome. Apparently, this mRNA is not translated in a single reading frame with standard codon usage. Our examination of the nucleotide sequence and three-frame translation of the mRNA suggest that the reading frame must be shifted 10 times, at every AGG and CCC codon, to yield a consensus COX1 protein. We suggest two possible mechanisms for these translational frameshifts: a ribosomal frameshift in which stalled ribosomes skip the first bases of these codons or specialized tRNAs recognizing non-triplet codons, AGGY and CCCCU. Regardless of the mechanism, active and efficient machinery would be required to tolerate the frameshifts predicted in Perkinsus mitochondria. To our knowledge, this is the first evidence of translational frameshifts in protist mitochondria and, by far, is the most extensive case in mitochondria. PMID:20507907

  12. Details of the structure determination of the sulfated steroids PSDS and PADS: new components of the sea lamprey (petromyzon marinus) migratory pheromone.

    PubMed

    Hoye, Thomas R; Dvornikovs, Vadims; Fine, Jared M; Anderson, Kari R; Jeffrey, Christopher S; Muddiman, David C; Shao, Feng; Sorensen, Peter W; Wang, Jizhou

    2007-09-28

    The discovery of two new components of the migratory pheromone used by sea lamprey to guide adults to spawning grounds was recently reported. These hold promise for use in a pheromone-based control program for this species, an invasive pest in the Great Lakes. Details of the structure determination of these steroidal bis-sulfates [petromyzosterol disulfate (PSDS, 2) and petromyzonamine disulfate (PADS, 3)] are described here. Pattern matching of 1H NMR data was particularly valuable. This involved comparison of spectra of the natural samples of 2 and 3 with those of appropriate steroidal analogues [e.g., petromyzonol sulfate (PS, 1, a previously known sea lamprey bile acid derivative that is a third component of the migratory pheromone), cholesterol sulfate (6), and squalamine (8)] and model compounds containing the unprecedented aminolactam substructure present in 3. The logic underlying the iterative analyses used is presented. PMID:17718505

  13. EFFECTS OF FRESHWATER RELEASES AND SEASON ON OYSTERS (CRASSOSTREA VIRGINICA) IN CALOOSAHATCHEE ESTUARY, FLORIDA

    EPA Science Inventory

    The influence of freshwater releases and season on disease prevalence and intensity of Perkinsus marinus, condition index, gonadal condition, recruitment potential, and growth of oysters was examined monthly at five locations along the Caloosahatchee estuary, Florida. Temperature...

  14. EFFECTS OF SEASONAL AND WATER QUALITY PARAMETERS ON OYSTERS (CRASSOSTREA VIRGINICA) AND ASSOCIATED FISH POPULATIONS.

    EPA Science Inventory

    Influence of water quality and seasonal changes on disease prevalence and intensity of Perkinsus marinus, gonadal condition, recruitment potential, growth of caged juvenile oysters, and habitat suitability of reefs for fishes and macrobenthic invertebrates were measured in Callos...

  15. PERKINSUS-"CIDAL" ACTIVITY OF OYSTER HEMOCYTES USING A TETRAZOLIUM DYE REDUCTION ASSAY: OPTIMIZATION AND APPLICATIONS

    EPA Science Inventory

    A bactericidal assay developed to assess the ability of oyster (Crassostrea virginica) hemocytes to kill the human pathogen Vibrio parahaemolyticus was optimized to estimate killing of the oyster parasite Perkinsus marinus. Assay variables, temperature, hemocyte:parasite ratio, i...

  16. PROTOZOAL INFECTIONS OF THE EASTERN OYSTER (CRASSOSTREA VIRGINICA) IN THE UPPER CHESAPEAKE BAY: A POTENTIAL ECOLOGICAL FORECAST

    EPA Science Inventory

    Perkinsus marinus and Haplosporidium nelsoni cause devasting infections in populations of the eastern oyster, Crassostrea virginica, along the US Atlantic coast and Gulf of Mexico. Salinity and temperature are considered major controlling factors in the prevalence and infection i...

  17. Draft Genome Sequences of Gammaproteobacterial Methanotrophs Isolated from Marine Ecosystems.

    PubMed

    Flynn, James D; Hirayama, Hisako; Sakai, Yasuyoshi; Dunfield, Peter F; Klotz, Martin G; Knief, Claudia; Op den Camp, Huub J M; Jetten, Mike S M; Khmelenina, Valentina N; Trotsenko, Yuri A; Murrell, J Colin; Semrau, Jeremy D; Svenning, Mette M; Stein, Lisa Y; Kyrpides, Nikos; Shapiro, Nicole; Woyke, Tanja; Bringel, Françoise; Vuilleumier, Stéphane; DiSpirito, Alan A; Kalyuzhnaya, Marina G

    2016-01-01

    The genome sequences of Methylobacter marinus A45, Methylobacter sp. strain BBA5.1, and Methylomarinum vadi IT-4 were obtained. These aerobic methanotrophs are typical members of coastal and hydrothermal vent marine ecosystems. PMID:26798114

  18. Draft Genome Sequences of Gammaproteobacterial Methanotrophs Isolated from Marine Ecosystems

    PubMed Central

    Flynn, James D.; Hirayama, Hisako; Sakai, Yasuyoshi; Dunfield, Peter F.; Knief, Claudia; Op den Camp, Huub J. M.; Jetten, Mike S. M.; Khmelenina, Valentina N.; Trotsenko, Yuri A.; Murrell, J. Colin; Semrau, Jeremy D.; Svenning, Mette M.; Stein, Lisa Y.; Kyrpides, Nikos; Shapiro, Nicole; Woyke, Tanja; Bringel, Françoise; Vuilleumier, Stéphane; DiSpirito, Alan A.

    2016-01-01

    The genome sequences of Methylobacter marinus A45, Methylobacter sp. strain BBA5.1, and Methylomarinum vadi IT-4 were obtained. These aerobic methanotrophs are typical members of coastal and hydrothermal vent marine ecosystems. PMID:26798114

  19. Assessment of fecal bacteria with bile acid 7 alpha-dehydroxylating activity for the presence of bai-like genes.

    PubMed Central

    Doerner, K C; Takamine, F; LaVoie, C P; Mallonee, D H; Hylemon, P B

    1997-01-01

    Eubacterium sp. strain VPI 12708 has several bile acid-inducible (bai) genes which encode enzymes in the bile acid 7 alpha-dehydroxylation (7 alpha DeOH) pathway. Twelve 7 alpha DeOH-positive intestinal bacterial strains were assayed for 7 alpha DeOH activity, and 13 strains were tested for hybridization with bai genes. Cholic acid 7 alpha DeOH activity varied greatly (> 100-fold) among these strains. Southern blot experiments showed that DNA prepared from 7 of 13 strains hybridized with at least one of the bai genes from Eubacterium sp. strain VPI 12708. PMID:9055436

  20. Assessment of the northern distribution range of selected Perkinsus species in eastern oysters (Crassostrea virginica) and hard clams (Mercenaria mercenaria) with the use of PCR-based detection assays.

    PubMed

    Pecher, Wolf T; Alavi, Mohammad R; Schott, Eric J; Fernandez-Robledo, José A; Roth, Laura; Berg, Sean T; Vasta, Gerardo R

    2008-04-01

    Perkinsus species are protistan parasites of molluscs. In Chesapeake Bay, Perkinsus marinus, Perkinsus chesapeaki, and Perkinsus andrewsi are sympatric, infecting oysters and clams. Although P. marinus is a pathogen for Crassostrea virginica, it remains unknown whether P. andrewsi and P. chesapeaki are equally pathogenic. Perkinsus species have been reported in C. virginica as far north as Maine, sometimes associated with high prevalence, but low mortality. Thus, we hypothesized that, in addition to P. marinus, Perkinsus species with little or no pathogenicity for C. virginica may be present. Accordingly, we investigated the distribution of Perkinsus species in C. virginica and Mercenaria mercenaria, collected from Maine to Virginia, by applying PCR-based assays specific for P. marinus, P. andrewsi, and a Perkinsus sp. isolated from M. mercenaria. DNA samples of M. mercenaria possessed potent PCR inhibitory activity, which was overcome by the addition of 1 mg/ml BSA and 5% (v/v) DMSO to the PCR reaction mixture. All 3 Perkinsus species were found in both host species throughout the study area. Interestingly, the prevalence of P. marinus in M. mercenaria was significantly lower than in C. virginica, suggesting that M. mercenaria is not an optimal host for P. marinus. PMID:18564742

  1. In vitro susceptibility of anaerobic bacteria to ciprofloxacin (Bay o 9867).

    PubMed Central

    Prabhala, R H; Rao, B; Marshall, R; Bansal, M B; Thadepalli, H

    1984-01-01

    About 80% of 70 clinical isolates of Bacteroides fragilis were inhibited by 4 micrograms of ciprofloxacin (Bay o 9867) per ml. The 90% MIC of ciprofloxacin was 8 micrograms/ml for other Bacteroides species, 2 micrograms/ml for Peptococcus species, 8 micrograms/ml for Peptostreptococcus species, and 16 micrograms/ml for Clostridium and Eubacterium species. PMID:6517561

  2. Genetic Resistance-ease of acquisition and role of commensals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The majority of the normal intestinal microflora is composed of anaerobic Gram-positive and Gram-negative bacteria such as Bifidobacterium, Eubacterium, and Bacteroides. Other minor inhabitants consist of facultative Gram-negative and Gram-positive bacteria including Escherichia coli and Enterococc...

  3. Comparison of protein expression profiles between three Perkinsus spp., protozoan parasites of molluscs, through 2D electrophoresis and mass spectrometry.

    PubMed

    Fernández-Boo, S; Chicano-Gálvez, E; Alhama, J; Barea, J L; Villalba, A; Cao, A

    2014-05-01

    The genus Perkinsus includes protozoan parasites of a wide range of marine molluscs worldwide, some of which have been responsible for heavy mollusc mortalities and dramatic economic losses. This study was performed with the aim of increasing the knowledge of Perkinsus spp. proteome. Proteins extracted from in vitro cultured cells of three species of this genus, P. marinus, P. olseni and P. chesapeaki, were analysed using 2D electrophoresis. Four gels from each species were produced. Qualitative and quantitative comparisons among gels were performed with Proteamweaver software. Cluster analysis grouped the four gels of each Perkinsus sp.; furthermore, P. marinus and P. olseni gels were grouped in a cluster different from P. chesapeaki. Around 2000 spots of each species were considered, from which 213 spots were common to the 3 species; P. chesapeaki and P. marinus shared 310 spots, P. chesapeaki and P. olseni shared 315 spots and P. marinus and P. olseni shared 242 spots. A number of spots were exclusive of each Perkinsus species: 1161 spots were exclusive of P. chesapeaki, 1124 of P. olseni and 895 of P. marinus. A total of 84 spots, including common and species-specific ones, were excised from the gels and analysed using MALDI-TOF and nESI-IT (MS/MS) techniques. Forty-two spots were successfully sequenced, from which 28 were annotated, most of them clustered into electron transport, oxidative stress and detoxification, protein synthesis, carbohydrate metabolism, signal transduction, metabolic process and proteolysis. PMID:24607654

  4. Assessment of Virally Vectored Autoimmunity as a Biocontrol Strategy for Cane Toads

    PubMed Central

    Robinson, Anthony J.; Venables, Daryl; Voysey, Rhonda D.; Boyle, Donna G.; Shanmuganathan, Thayalini; Hardy, Christopher M.; Siddon, Nicole A.; Hyatt, Alex D.

    2011-01-01

    Background The cane toad, Bufo (Chaunus) marinus, is one of the most notorious vertebrate pests introduced into Australia over the last 200 years and, so far, efforts to identify a naturally occurring B. marinus-specific pathogen for use as a biological control agent have been unsuccessful. We explored an alternative approach that entailed genetically modifying a pathogen with broad host specificity so that it no longer caused disease, but carried a gene to disrupt the cane toad life cycle in a species specific manner. Methodology/Principal Findings The adult beta globin gene was selected as the model gene for proof of concept of autoimmunity as a biocontrol method for cane toads. A previous report showed injection of bullfrog tadpoles with adult beta globin resulted in an alteration in the form of beta globin expressed in metamorphs as well as reduced survival. In B. marinus we established for the first time that the switch from tadpole to adult globin exists. The effect of injecting B. marinus tadpoles with purified recombinant adult globin protein was then assessed using behavioural (swim speed in tadpoles and jump length in metamorphs), developmental (time to metamorphosis, weight and length at various developmental stages, protein profile of adult globin) and genetic (adult globin mRNA levels) measures. However, we were unable to detect any differences between treated and control animals. Further, globin delivery using Bohle iridovirus, an Australian ranavirus isolate belonging to the Iridovirus family, did not reduce the survival of metamorphs or alter the form of beta globin expressed in metamorphs. Conclusions/Significance While we were able to show for the first time that the switch from tadpole to adult globin does occur in B. marinus, we were not able to induce autoimmunity and disrupt metamorphosis. The short development time of B. marinus tadpoles may preclude this approach. PMID:21283623

  5. Survey for protozoan parasites in Eastern oysters (Crassostrea virginica) from the Gulf of Maine using PCR-based assays.

    PubMed

    Marquis, Nicholas D; Record, Nicholas R; Robledo, José A Fernández

    2015-10-01

    Protozoan pathogens represent a serious threat to oyster aquaculture, since they can lead to significant production loses. Moreover, oysters can concentrate human pathogens through filter feeding, thus putting at risk raw oyster consumers' health. Using PCR-based assays in oysters (Crassostrea virginica) from Maine, we expand the Northeast range in the USA for the protozoans Perkinsus marinus, Perkinsus chesapeaki, and Haplosporidium nelsoni, and report for the first time the detection of the human pathogens Toxoplasma gondii and Cryptosporidium parvum. Oysters hosting both P. marinus and P. chesapeaki were more than three times as likely to be infected by a non-Perkinsus than those free of Perkinsus infections. PMID:25889457

  6. Anaerobic bacteria from the large intestine of mice.

    PubMed Central

    Harris, M A; Reddy, C A; Carter, G R

    1976-01-01

    Anaerobic bacteria from the colon of laboratory mice were enumerated and isolated using strict anaerobic techniques. Direct microscopic counts revealed 4.4 X 10(10) organisms in each gram (wet weight) of colon contents. Actual cultural counts averaged 3.2 X 10(10) organisms, which was 73% of the direct microscopic count. The tentatively identified genera were Bacteroides, Eubacterium, Fusobacterium, Lactobacillus, Peptostreptococcus, and Propionibacterium. Strains of Fusobacterium, Lactobacillus, Peptostreptococcus, and Propionibacterium were biochemically homogeneous. Strains of Bacteroides and Eubacterium, on the other hand, were biochemically heterogeneous and were subdivided into several distinct groups. The data indicate that many of the isolates are different from previously described species of the respective genera and may belong to new species. PMID:938042

  7. NMR bioreactor development for live in-situ microbial functional analysis

    SciTech Connect

    Majors, Paul D.; Mclean, Jeffrey S.; Scholten, Johannes C.

    2008-05-01

    A live in-situ metabolomics capability was developed for prokaryotic cultures under controlled-growth conditions. Toward this goal, a radiofrequency-transparent bioreactor was developed and integrated with a commercial wide-bore nuclear magnetic resonance (NMR) imaging spectrometer and a commercial bioreactor controller. Water suppressed 1H NMR spectroscopy was used to monitor glucose and fructose utilization and byproduct excretion by Eubacterium aggregans (an anaerobic bacterial species relevant for biofuels production) under controlled batch and continuous culture conditions. The resulting metabolite profiles (short chain organic acids and ethanol) and trends are consistent with existing knowledge of its metabolism. However, our study showed the Eubacterium aggregans produces lactate end product in significant concentrations – a result not previously reported. The advantages of live in-situ microbial metabolomics analysis and its complementariness with functional genomics / systems biology methods are discussed.

  8. In vitro determination of prebiotic properties of oligosaccharides derived from an orange juice manufacturing by-product stream.

    PubMed

    Manderson, K; Pinart, M; Tuohy, K M; Grace, W E; Hotchkiss, A T; Widmer, W; Yadhav, M P; Gibson, G R; Rastall, R A

    2005-12-01

    Fermentation properties of oligosaccharides derived from orange peel pectin were assessed in mixed fecal bacterial culture. The orange peel oligosaccharide fraction contained glucose in addition to rhamnogalacturonan and xylogalacturonan pectic oligosaccharides. Twenty-four-hour, temperature- and pH-controlled, stirred anaerobic fecal batch cultures were used to determine the effects that oligosaccharides derived from orange products had on the composition of the fecal microbiota. The effects were measured through fluorescent in situ hybridization to determine changes in bacterial populations, fermentation end products were analyzed by high-performance liquid chromatography to assess short-chain fatty acid concentrations, and subsequently, a prebiotic index (PI) was determined. Pectic oligosaccharides (POS) were able to increase the bifidobacterial and Eubacterium rectale numbers, albeit resulting in a lower prebiotic index than that from fructo-oligosaccharide metabolism. Orange albedo maintained the growth of most bacterial populations and gave a PI similar to that of soluble starch. Fermentation of POS resulted in an increase in the Eubacterium rectale numbers and concomitantly increased butyrate production. In conclusion, this study has shown that POS can have a beneficial effect on the fecal microflora; however, a classical prebiotic effect was not found. An increase in the Eubacterium rectale population was found, and butyrate levels increased, which is of potential benefit to the host. PMID:16332825

  9. A method of marking larval lampreys

    USGS Publications Warehouse

    Wigley, Roland L.

    1952-01-01

    Biological investigations of lamprey populations in central New York have indicated a need for developing a method of marking larvae of the sea lamprey, Petromyzon marinus Linnaeus, and the American brook lamprey, Lampetra lamottei (Lesueur) Since lamprey larvae live in burrows in the soft sediments of the stream bottom, the use of an external tag is impractical.

  10. NORTHWARD EXPANSION OF A MARINE PARASITE: TESTING THE ROLE OF TEMPERATURE ADAPTATION

    EPA Science Inventory

    The known range of the eastern oyster (Crassostrea virginica) parasite, Perkinsus marinus, expanded into the northeastern United States in the early 1990s. We used both in vitro and in vivo data to test the hypothesis that the northward expansion was associated with a low-tempera...

  11. Does Implicit Learning in Non-Demented Parkinson's Disease depend on the Level of Cognitive Functioning?

    ERIC Educational Resources Information Center

    Vandenbossche, Jochen; Deroost, Natacha; Soetens, Eric; Kerckhofs, Eric

    2009-01-01

    We investigated the influence of the level of cognitive functioning on sequence-specific learning in Parkinson's disease (PD). This was done by examining the relationship between the scales for outcomes in Parkinson's disease-cognition [SCOPA-COG, Marinus, J., Visser, M., Verwey, N. A., Verhey, F. R. J., Middelkoop, H. A. M.,Stiggelbout, A., et…

  12. The performance of oyster families exposed to Dermo disease is contingent on the source of pathogen exposure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here we report preliminary results from a course of research integrating pathology, feeding ecology, genetics and genomics to address resistance to Dermo disease in eastern oysters. We challenged six oyster families with Perkinsus marinus, the etiological agent of Dermo disease, through either direc...

  13. Application of a multiplex PCR for the detection of protozoan pathogens of the eastern oyster Crassostrea virginica in field samples.

    PubMed

    Russell, Spencer; Frasca, Salvatore; Sunila, Inke; French, Richard A

    2004-04-21

    Populations of eastern oysters Crassostrea virginica along the east coast of North America have repeatedly experienced epizootic mass mortality due to infections by protozoan parasites, and molecular diagnostic methodologies are fast becoming more widely available for the diagnosis of protozoan diseases of oysters. In this study we applied a modified version of an existing multiplex polymerase chain reaction (PCR) for detection of the eastern oyster parasites Haplosporidium nelsoni, H. costale and Perkinsus marinus from field-collected samples. We incorporated primers for DNA quality control based on the large subunit ribosomal RNA (LSU rRNA) gene of C. virginica. The multiplex PCR (MPCR) simultaneously amplified genomic DNA of C. virginica, and cloned DNA of H. nelsoni, P. marinus and H. costale. In field trial applications, we compared the performance of the MPCR to that of the conventional diagnostic techniques of histopathological tissue examination and the Ray/Mackin fluid thioglycollate medium (RMFT) assay. A total of 530 oysters were sampled from 18 sites at 12 locations along the east coast of the United States from the Gulf of Mexico to southern New England. The modified MPCR detected 21% oysters with H. nelsoni, 2% oysters with H. costale, and 40% oysters with P. marinus infections. In comparison, histopathological examination detected H. nelsoni and H. costale infections in 6 and 0.8% oysters, respectively, and the RMFT assay detected P. marinus infection in 31% oysters. The MPCR is a more sensitive diagnostic assay for detection of H. nelsoni, H. costale, and P. marinus, and incorporation of an oyster quality control product limits false negative results. PMID:15212297

  14. Evaluation of certain food additives. Seventy-first report of the Joint FAO/WHO Expert Committee on Food Additives.

    PubMed

    2010-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessment of intake of food additives. A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives: branching glycosyltransferase from Rhodothermus obamensis expressed in Bacillus subtilis, cassia gum, cyclamic acid and its salts (dietary exposure assessment), cyclotetraglucose and cyclotetraglucose syrup, ferrous ammonium phosphate, glycerol ester of gum rosin, glycerol ester of tall oil rosin, lycopene from all sources, lycopene extract from tomato, mineral oil (low and medium viscosity) class II and class III, octenyl succinic acid modified gum arabic, sodium hydrogen sulfate and sucrose oligoesters type I and type II. Specifications for the following food additives were revised: diacetyltartaric acid and fatty acid esters of glycerol, ethyl lauroyl arginate, glycerol ester of wood rosin, nisin preparation, nitrous oxide, pectins, starch sodium octenyl succinate, tannic acid, titanium dioxide and triethyl citrate. Annexed to the report are tables summarizing the Committee's recommendations for intakes and toxicological evaluations of the food additives considered. PMID:20942228

  15. [Specification of species status of some colleciton strains of methanotrophs].

    PubMed

    Romanovskaia, V A; Rokitko, P V; Shilin, S O; Chernaia, N A

    2009-01-01

    Sequence-analysis of genes 16S rRNA has demonstrated the high-level relationship (99%) of the strains Methylobacter ucrainicus UCM B-3159, and Methylobacter marinus A45(T). The strain UCM B-3159 has lower coefficients of similarity (97.4-96.4%) for other species of that genus. These strains are similar as to their phenotypical properties and form one branch on the dendrogram which demonstrates species relations of Methylococcaceae family, that permitted reclassifying M. ucrainicus as M. marinus. Phylogenetic analysis has confirmed the belonging of strains UCM B-3002 and UCM B-3494 to Methylococcus capsulatus species. Those strains were earlier related to this species on the basis of phenotype features. PMID:19663320

  16. Aliphatic Hydrocarbons and Fatty Acids of Some Marine and Freshwater Microorganisms

    PubMed Central

    Oró, J.; Tornabene, T. G.; Nooner, D. W.; Gelpi, E.

    1967-01-01

    Gas chromatography and combined gas chromatography-mass spectrometry have been used to study the fatty acids and hydrocarbons of a bacterium from the Pacific Ocean, Vibrio marinus, a freshwater blue-green alga, Anacystis nidulans, and algal mat communities from the Gulf of Mexico. Both types of microorganisms (bacteria and algae) showed relatively simple hydrocarbon and fatty acid patterns, the hydrocarbons predominating in the region of C-17 and the fatty acids in the range of C-14 to C-18. The patterns of V. marinus were more comparable to those of the algal populations than to patterns reported for other bacteria. An incomplete correlation between fatty acids and hydrocarbons in both types of organisms was observed, making it difficult to accept the concept that the biosynthesis of hydrocarbons follows a simple fatty acid decarboxylation process. PMID:6025301

  17. A surface tow net for collection of parasitic-phase sea lampreys

    USGS Publications Warehouse

    Dahl, Frederick H.

    1968-01-01

    A STUDY OF MIGRATORY BEHAVIOR of parasitic sea lampreys (Petromyzon marinus) in the Great Lakes required a means of capturing lampreys for tagging and releasing in St. Marys River, Lake Huron. Smith and Elliott (1953) fished specially made gill and trap nets for sea lampreys, but stationary nets could not be used in the St. Marys River because of boat traffic, interference with sport fishermen, and fast currents.

  18. Toad Intoxication in the Dog by Rhinella marina : The Clinical Syndrome and Current Treatment Recommendations.

    PubMed

    Johnnides, Stephanie; Green, Tiffany; Eubig, Paul

    2016-01-01

    Oral exposure to the secretions of Rhinella marina (formerly Bufo marinus ) can carry a high fatality rate without early and appropriate treatment. In dogs, the clinical syndrome, which is evident almost immediately, manifests in profuse ptyalism along with gastrointestinal, respiratory, and neurologic signs. Severe cardiac arrhythmias develop less frequently. This review will cover the history, toxicology, and clinical syndrome of Rhinella marina intoxication, and will discuss the recommended therapies for stabilization. PMID:27259028

  19. Diatoms as food of larval sea lampreys in a small tributary of northern Lake Michigan

    USGS Publications Warehouse

    Manion, Patrick J.

    1967-01-01

    The food and food preferences of sea lamprey ammocoetes have not been investigated. The food of the larval American brook lamprey, Lampetra lamottei, in the Great Lakes region consisted mainly of diatoms and desmids according to Creaser and Hann. Schroll discussed the biology of feeding of ammocoetes of Lampetra planeri and Eudontomyzon danfordi in Europe. This report presents data on the availability and use of diatoms by sea lamprey, Petromyzon marinus Linnaeus, ammocoetes in a small tributary of northern Lake Michigan.

  20. Identification of potential general markers of disease resistance in American oysters, Crassostrea virginica through gene expression studies.

    PubMed

    Nikapitiya, Chamilani; McDowell, Ian C; Villamil, Luisa; Muñoz, Pilar; Sohn, SaeBom; Gomez-Chiarri, Marta

    2014-11-01

    Several diseases have a significant impact on American oyster populations in the Atlantic coasts of North America. Knowledge about the responses of oysters to pathogenic challenge could help in identifying potential markers of disease resistance and biomarkers of the health status of an oyster population. A previous analysis of the transcriptome of resistant and susceptible American oysters in response to challenge with the bacterial pathogen Roseovarius crassostreae, as well as sequencing of suppression subtractive hybridization libraries from oysters challenged with the protozoan parasite Perkinsus marinus, provided a list of genes potentially involved in disease resistance or susceptibility. We investigated the patterns of inducible gene expression of several of these genes in response to experimental challenge with the oyster pathogens R. crassostreae, Vibrio tubiashii, and P. marinus. Oysters showing differential susceptibility to R. crassostreae demonstrated differential patterns of expression of genes coding for immune (serine protease inhibitor-1, SPI1) and stress-related (heat shock protein 70, HSP70; arginine kinase) proteins 30 days after challenge with this bacterial pathogen. Differential patterns of expression of immune (spi1, galectin and a matrix metalloproteinase) and stress-related (hsp70, histone H4, and arginine kinase) genes was observed in hemocytes from adult oysters challenged with P. marinus, but not with V. tubiashii. While levels of spi1 expression in hemocytes collected 8 and 21 days after P. marinus challenge were negatively correlated with parasite load in oysters tissues at the end of the challenge (62 days), levels of expression of hsp70 in hemocytes collected 1-day after challenge were positively correlated with oyster parasite load at 62 days. Our results confirm previous research on the role of serine protease inhibitor-1 in immunity and disease resistance in oysters. They also suggest that HSP70 and histone H4 could be used

  1. Physiological and pathological changes in the eastern oyster Crassostrea virginica infested with the trematode Bucephalus sp. and exposed to the toxic dinoflagellate Alexandrium fundyense.

    PubMed

    Lassudrie, Malwenn; Wikfors, Gary H; Sunila, Inke; Alix, Jennifer H; Dixon, Mark S; Combot, Doriane; Soudant, Philippe; Fabioux, Caroline; Hégaret, Hélène

    2015-03-01

    Effects of experimental exposure to Alexandrium fundyense, a Paralytic Shellfish Toxin (PST) producer known to affect bivalve physiological condition, upon eastern oysters, Crassostrea virginica with a variable natural infestation of the digenetic trematode Bucephalus sp. were determined. After a three-week exposure to cultured A. fundyense or to a control algal treatment with a non-toxic dinoflagellate, adult oysters were assessed for a suite of variables: histopathological condition, hematological variables (total and differential hemocyte counts, morphology), hemocyte functions (Reactive Oxygen Species (ROS) production and mitochondrial membrane potential), and expression in gills of genes involved in immune responses and cellular protection (MnSOD, CAT, GPX, MT-IV, galectin CvGal) or suspected to be (Dominin, Segon). By comparing individual oysters infested heavily with Bucephalus sp. and uninfested individuals, we found altered gonad and digestive gland tissue and an inflammatory response (increased hemocyte concentration in circulating hemolymph and hemocyte infiltrations in tissues) associated with trematode infestation. Exposure to A. fundyense led to a higher weighted prevalence of infection by the protozoan parasite Perkinsus marinus, responsible for Dermo disease. Additionally, exposure to A. fundyense in trematode-infested oysters was associated with the highest prevalence of P. marinus infection. These observations suggest that the development of P. marinus infection was advanced by A. fundyense exposure, and that, in trematode-infested oysters, P. marinus risk of infection was higher when exposed to A. fundyense. These effects were associated with suppression of the inflammatory response to trematode infestation by A. fundyense exposure. Additionally, the combination of trematode infestation and A. fundyense exposure caused degeneration of adductor muscle fibers, suggesting alteration of valve movements and catch state, which could increase

  2. Croceicoccus naphthovorans sp. nov., a polycyclic aromatic hydrocarbons-degrading and acylhomoserine-lactone-producing bacterium isolated from marine biofilm, and emended description of the genus Croceicoccus.

    PubMed

    Huang, Yili; Zeng, Yanhua; Feng, Hao; Wu, Yuehong; Xu, Xuewei

    2015-05-01

    A polycyclic aromatic hydrocarbons-degrading and acylhomoserine-lactone-producing marine bacterium, designated strain PQ-2(T), was isolated from marine biofilm collected from a boat shell at a harbour of Zhoushan island in Zhejiang Province, PR China. Strain PQ-2(T) is Gram-stain-negative, yellow-pigmented, non-motile and short rod-shaped. Optimal growth of strain PQ-2(T) was observed at 32 °C, at pH 7.0 and in 2% (w/v) NaCl. The 16S rRNA gene sequence of strain PQ-2(T) showed highest similarity to Croceicoccus marinus E4A9(T) (96.3%) followed by Novosphingobium malaysiense MUSC 273(T) (95.6%) and Altererythrobacter marinus H32(T) (95.6%). Phylogenetic analysis with all species of the family Erythrobacteraceae with validly published names revealed that strain PQ-2(T) formed a phyletic line with Croceicoccus marinus E4A9(T) that was distinct from other members of the family Erythrobacteraceae . The sole respiratory quinone was ubiquinone 10 (Q-10). The predominant fatty acids were C18 : 1ω7c, C17 : 1ω6c and summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH). The genomic DNA G+C content was 61.7 mol%. In the polar lipid profile, phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, one unidentified phospholipid and one sphingoglycolipid were the major compounds; and another sphingoglycolipid was present in a minor amount. Based on the genotypic and phenotypic data, strain PQ-2(T) represents a novel species of the genus Croceicoccus , for which the name Croceicoccus naphthovorans sp. nov. is proposed. The type strain is PQ-2(T) ( =CGMCC 1.12805(T) =NBRC 110381(T)). In addition, emended descriptions for the genus Croceicoccus and the species C. marinus are given. PMID:25713040

  3. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus

    PubMed Central

    Cold, Emma R.; Freyria, Nastasia J.; Martínez Martínez, Joaquín; Fernández Robledo, José A.

    2016-01-01

    The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham’s F12–5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1) Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham’s F12–5% FBS– 0.75% agar plates, which could be further propagated in liquid medium; 2) Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3) Chemical susceptibility: Infusing the DME: Ham’s F12–5% FBS– 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications. PMID:27149378

  4. The Nuclear DNA Content and Genetic Diversity of Lampetra morii

    PubMed Central

    Yan, Xinyu; Meng, Wenbin; Wu, Fenfang; Xu, Anlong; Chen, Shangwu; Huang, Shengfeng

    2016-01-01

    We investigated the nuclear DNA content and genetic diversity of a river lamprey, the Korean lamprey Lampetra morii, which is distributed in the northeast of China. L. morii spends its whole life cycle in fresh water, and its adult size is relatively small (~160 mm long) compared with that of other lampreys. The haploid nuclear DNA content of L. morii is 1.618 pg (approximately 1.582 Gb) in germline cells, and there is ~15% germline DNA loss in somatic cells. These values are significantly smaller than those of Petromyzon marinus, a lamprey with a published draft genome. The chromosomes of L. morii are small and acrocentric, with a diploid modal number of 2n = 132, lower than some other lampreys. Sequence and AFLP analyses suggest that the allelic polymorphism rate (~0.14% based on examined nuclear and mitochondrial DNA sequences) of L. morii is much lower than that (~2%) of P. marinus. Phylogenetic analysis based on a mitochondrial DNA fragment confirms that L. morii belongs to the genus Lampetra, which, together with the genus Lethenteron, forms a sister group to P. marinus. These genetic background data are valuable for subsequent genetic and genomic research on L. morii. PMID:27388621

  5. Morphology of three species of Amphileptus (Protozoa, Ciliophora, Pleurostomatida) from the South China Sea, with note on phylogeny of A. dragescoi sp. n.

    PubMed

    Pan, Hongbo; Li, Lifang; Lin, Xiaofeng; Li, Jiqiu; Al-Farraj, Saleh A; Al-Rasheid, Khaled A

    2014-01-01

    Two new and one problematic species of pleurostomatids, Amphileptus dragescoi sp. n., A. wilberti sp. n., and A. marinus from coastal areas of the South China Sea, are described based on observations of live and protargol-impregnated specimens. Amphileptus dragescoi is different from its congeners by the presence of an apical group of extrusomes and the possession of 12-15 right and five left somatic kineties, two macronuclear nodules, and a single terminally positioned contractile vacuole. Amphileptus wilberti is diagnosed by oval or pyriform body, 15-19 right and seven or eight left somatic kineties, extrusomes arranged only in anterior portion of oral slit, usually three ventrally located contractile vacuoles, and two macronuclear nodules. Amphileptus marinus (Kahl, 1931) Song et al., 2004 is redescribed and its diagnosis is improved. One isolate which was misidentified as A. marinus by Song et al. (2004) is believed to represent an unknown form, named here as Amphileptus songi sp. n. Phylogenetic analyses of the SSU rDNA sequences indicate that the genus Amphileptus is paraphyletic, but its monophyly is not rejected by statistical tree topology tests. PMID:25041259

  6. Effects of nonindigenous tadpoles on native tadpoles in Florida: Evidence of competition

    USGS Publications Warehouse

    Smith, Kimberly G.

    2005-01-01

    The impacts of nonindigenous species on native ecosystems can be severe, sometimes leading to the extinction of native taxa. Interspecific competition is a potential mechanism of negative impact of invasive species, but few studies have conclusively demonstrated competition between native and nonindigenous taxa. In this study I used experimental manipulations to examine the competitive effects of the larvae of two widely introduced anurans, the cane toad, Bufo marinus, and the Cuban treefrog, Osteopilus septentrionalis, on the growth and development of the larvae of two native anurans (the southern toad, Bufo terrestris, and the green treefrog, Hyla cinerea). The presence of O. septentrionalis larvae consistently impacted growth and development of native larvae, resulting in reduced growth rates and delayed metamorphosis of both native species and smaller mass at metamorphosis of B. terrestris. Hyla cinerea larvae transformed at greater body masses when reared with the rapidly transforming nonindigenous species as a result of competitive release. The negative effects of O. septentrionalis on native larvae were generally significant whether native tadpoles were exposed to O. septentrionalis alone or in combination with B. marinus. In contrast, B. marinus tadpoles did not significantly impact the growth or development of either native species. Neither nonindigenous species significantly decreased the survivorship of native larvae, although a trend toward decreased survivorship was evident for H. cinerea. These results suggest that nonindigenous larval anurans may adversely impact native tadpole communities as a result of interspecific competition.

  7. Spatial and temporal distributions of contaminant body burden and disease in Gulf of Mexico oyster populations: The role of local and large-scale climatic controls

    NASA Astrophysics Data System (ADS)

    Wilson, E. A.; Powell, E. N.; Wade, T. L.; Taylor, R. J.; Presley, B. J.; Brooks, J. M.

    1992-06-01

    As part of NOAA's Status and Trends Program, oysters were sampled from 43 sites throughout the Gulf of Mexico from Brownsville, Texas, to the Florida Everglades from 1986 to 1989. Oysters were analysed for body burden of a suite of metals and petroleum aromatic hydrocarbons (PAHs), the prevalence and intensity of the oyster pathogen, Perkinsus marinus, and condition index. The contaminants fell into two groups based on the spatial distribution of body burden throughout the Gulf. Arsenic, selenium, mercury and cadmium were characterized by clinal reduction in similarity with distance reminiscent of that followed by mean monthly temperature and precipitation. Zinc, copper, PAHs and silver showed no consistent geographic trend. Within local regions, industrial and agricultural and use and P. marinus prevalence and infection intensity frequently correlated with body burden. Contaminants and biological attributes followed one of three temporal trends. Zinc, copper and PAHs showed concordant shifts over 4 years throughout the eastern and southern Gulf. Mercury and cadmium showed concordant shifts in the northwestern Gulf. Selenium, arsenic, length, condition index and P. marinus prevalence and infection intensity showed concordant shifts throughout most of the entire Gulf. Concordant shifts suggest that climatic factors, the El Niño/Southern Oscillation being one example, exert a strong influence on biological attributes and contaminant body burdens in the Gulf. Correlative factors are those that probably affect or indicate the rate of tissue turnover and the frequency of reproduction; namely, temperature, disease intensity, condition index and length.

  8. Assessing estuarine quality: A cost-effective in situ assay with amphipods.

    PubMed

    Martinez-Haro, Monica; Acevedo, Pelayo; Pais-Costa, Antónia Juliana; Taggart, Mark A; Martins, Irene; Ribeiro, Rui; Marques, João Carlos

    2016-05-01

    In situ assays based on feeding depression can be powerful ecotoxicological tools that can link physiological organism-level responses to population and/or community-level effects. Amphipods are traditional target species for toxicity tests due to their high sensitivity to contaminants, availability in the field and ease of handling. However, cost-effective in situ assays based on feeding depression are not yet available for amphipods that inhabit estuarine ecosystems. The aim of this work was to assess a short-term in situ assay based on postexposure feeding rates on easily quantifiable food items with an estuarine amphipod. Experiments were carried out under laboratory conditions using juvenile Echinogammarus marinus as the target individual. When 60 Artemia franciscana nauplii (as prey) were provided per individual for a period of 30 min in dark conditions, feeding rates could be easily quantified. As an endpoint, postexposure feeding inhibition in E. marinus was more sensitive to cadmium contamination than mortality. Assay calibration under field conditions demonstrated the relevance of sediment particle size in explaining individual feeding rates in uncontaminated water bodies. An evaluation of the 48-h in situ bioassay based on postexposure feeding rates indicated that it is able to discriminate between unpolluted and polluted estuarine sites. Using the harmonized protocol described here, the in situ postexposure feeding assay with E. marinus was found to be a potentially useful, cost-effective tool for assessing estuarine sediment and water quality. PMID:26874320

  9. An Agar-Based Method for Plating Marine Protozoan Parasites of the Genus Perkinsus.

    PubMed

    Cold, Emma R; Freyria, Nastasia J; Martínez Martínez, Joaquín; Fernández Robledo, José A

    2016-01-01

    The genus Perkinsus includes protozoan parasites of mollusks responsible for losses in the aquaculture industry and hampering the recovery of natural shellfish beds worldwide, and they are a key taxon for understanding intracellular parasitism adaptations. The ability to propagate the parasite in liquid media, in the absence of the host, has been crucial for improving understanding of its biology; however, alternative techniques to grow the parasite are needed to explore other basic aspects of the Perkinsus spp. biology. We optimized a DME: Ham's F12-5% FBS- containing solid agar medium for plating Perkinsus marinus. This solid medium supported trophozoite propagation both by binary fission and schizogony. Colonies were visible to the naked eye 17 days after plating. We tested the suitability of this method for several applications, including the following: 1) Subcloning P. marinus isolates: single discrete P. marinus colonies were obtained from DME: Ham's F12-5% FBS- 0.75% agar plates, which could be further propagated in liquid medium; 2) Subcloning engineered Perkinsus mediterraneus MOE[MOE]: GFP by streaking cultures on plates; 3) Chemical susceptibility: Infusing the DME: Ham's F12-5% FBS- 0.75% agar plates with triclosan resulted in inhibition of the parasite propagation in a dose-dependent manner. Altogether, our plating method has the potential for becoming a key tool for investigating diverse aspects of Perkinsus spp. biology, developing new molecular tools, and for biotechnological applications. PMID:27149378

  10. Upregulation in response to infection and antibacterial activity of oyster histone H4.

    PubMed

    Dorrington, Tarquin; Villamil, Luisa; Gómez-chiarri, Marta

    2011-01-01

    Several histones and histone-derived peptides have been shown to have antimicrobial activity and a potential role in innate immune defenses. A histone H4 sequence was identified in a subtractive suppression library containing genes upregulated in American cupped oysters, Crassostrea virginica, in response to challenge with the protozoan parasite Perkinsus marinus. Oyster histone H4 protein levels significantly increased in hemocyte lysates and cell free hemolymph of oysters experimentally challenged with P. marinus. The complete histone H4 coding sequence of C. virginica was cloned into a Saccharomyces cerevisiae yeast expression system and recombinant expression was confirmed using SDS-PAGE analysis and western blot. Delivery of yeast cells expressing recombinant oyster histone H4 into the gut of brine shrimp, Artemia salinas, challenged with a streptomycin resistant strain of Vibrio anguillarum resulted in a significant and dose-dependent decrease in the load of V. anguillarum. Purified recombinant histone H4 showed antimicrobial activity against V. anguillarum and Escherichia coli at micromolar concentrations, but did not affect the viability of P. marinus in culture. These results support the role of histone H4 in the defense of oysters against bacterial infection and validate the use of a novel oyster antimicrobial H4 in a yeast feed-based delivery system for the treatment of bacterial infections in aquaculture applications. PMID:20883794

  11. Alveolate phylogeny inferred using concatenated ribosomal proteins.

    PubMed

    Bachvaroff, Tsvetan R; Handy, Sara M; Place, Allen R; Delwiche, Charles F

    2011-01-01

    Dinoflagellates and apicomplexans are a strongly supported monophyletic group in rDNA phylogenies, although this phylogeny is not without controversy, particularly between the two groups. Here we use concatenated protein-coding genes from expressed sequence tags or genomic data to construct phylogenies including "typical" dinophycean dinoflagellates, a parasitic syndinian dinoflagellate, Amoebophrya sp., and two related species, Oxyrrhis marina, and Perkinsus marinus. Seventeen genes encoding proteins associated with the ribosome were selected for phylogenetic analysis. The dataset was limited for the most part by data availability from the dinoflagellates. Forty-five taxa from four major lineages were used: the heterokont outgroup, ciliates, dinoflagellates, and apicomplexans. Amoebophrya sp. was included in this phylogeny as a sole representative of the enigmatic marine alveolate or syndinian lineage. The atypical dinoflagellate O. marina, usually excluded from rDNA analyses due to long branches, was also included. The resulting phylogenies were well supported in concatenated analyses with only a few unstable or weakly supported branches; most features were consistent when different lineages were pruned from the tree or different genes were concatenated. The least stable branches involved the placement of Cryptosporidium spp. within the Apicomplexa and the relationships between P. marinus, Amoebophrya sp., and O. marina. Both bootstrap and approximately unbiased test results confirmed that P. marinus, Amoebophrya sp., O. marina, and the remaining dinoflagellates form a monophyletic lineage to the exclusion of Apicomplexa. PMID:21518081

  12. Senior Thai fecal microbiota comparison between vegetarians and non-vegetarians using PCR-DGGE and real-time PCR.

    PubMed

    Ruengsomwong, Supatjaree; Korenori, Yuki; Sakamoto, Naoshige; Wannissorn, Bhusita; Nakayama, Jiro; Nitisinprasert, Sunee

    2014-08-01

    The fecal microbiotas were investigated in 13 healthy Thai subjects using polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE). Among the 186 DNA bands detected on the polyacrylamide gel, 37 bands were identified as representing 11 species: Bacteroides thetaiotaomicron, Bacteroides ovatus, Bacteroides uniformis, Bacteroides vulgatus, Clostridium colicanis, Eubacterium eligenes, E. rectale, Faecalibacterium prausnitzii, Megamonas funiformis, Prevotella copri, and Roseburia intestinalis, belonging mainly to the groups of Bacteroides, Prevotella, Clostridium, and F. prausnitzii. A dendrogram of the PCR-DGGE divided the subjects; vegetarians and non-vegetarians. The fecal microbiotas were also analyzed using a quantitative real-time PCR focused on Bacteroides, Bifidobacterium, Enterobacteriaceae, Clostrium coccoides-Eubacterium rectale, C. leptum, Lactobacillus, and Prevotella. The nonvegetarian and vegetarian subjects were found to have significant differences in the high abundance of the Bacteroides and Prevotella genera, respectively. No significant differences were found in the counts of Bifidabacterium, Enterobacteriaceae, C. coccoides-E. rectale group, C. leptum group, and Lactobacillus. Therefore, these findings on the microbiota of healthy Thais consuming different diets could provide helpful data for predicting the health of South East Asians with similar diets. PMID:24743571

  13. The chimeric eukaryote: origin of the nucleus from the karyomastigont in amitochondriate protists

    NASA Technical Reports Server (NTRS)

    Margulis, L.; Dolan, M. F.; Guerrero, R.

    2000-01-01

    We present a testable model for the origin of the nucleus, the membrane-bounded organelle that defines eukaryotes. A chimeric cell evolved via symbiogenesis by syntrophic merger between an archaebacterium and a eubacterium. The archaebacterium, a thermoacidophil resembling extant Thermoplasma, generated hydrogen sulfide to protect the eubacterium, a heterotrophic swimmer comparable to Spirochaeta or Hollandina that oxidized sulfide to sulfur. Selection pressure for speed swimming and oxygen avoidance led to an ancient analogue of the extant cosmopolitan bacterial consortium "Thiodendron latens." By eubacterial-archaebacterial genetic integration, the chimera, an amitochondriate heterotroph, evolved. This "earliest branching protist" that formed by permanent DNA recombination generated the nucleus as a component of the karyomastigont, an intracellular complex that assured genetic continuity of the former symbionts. The karyomastigont organellar system, common in extant amitochondriate protists as well as in presumed mitochondriate ancestors, minimally consists of a single nucleus, a single kinetosome and their protein connector. As predecessor of standard mitosis, the karyomastigont preceded free (unattached) nuclei. The nucleus evolved in karyomastigont ancestors by detachment at least five times (archamoebae, calonymphids, chlorophyte green algae, ciliates, foraminifera). This specific model of syntrophic chimeric fusion can be proved by sequence comparison of functional domains of motility proteins isolated from candidate taxa.

  14. Analysis of genes encoding an alternative nitrogenase in the archaeon Methanosarcina barkeri 227.

    PubMed

    Chien, Y T; Auerbuch, V; Brabban, A D; Zinder, S H

    2000-06-01

    Methanosarcina barkeri 227 possesses two clusters of genes potentially encoding nitrogenases. We have previously demonstrated that one cluster, called nif2, is expressed under molybdenum (Mo)-sufficient conditions, and the deduced amino acid sequences for nitrogenase structural genes in that cluster most closely resemble those for the Mo nitrogenase of the gram-positive eubacterium Clostridium pasteurianum. The previously cloned nifH1 from M. barkeri shows phylogenetic relationships with genes encoding components of eubacterial Mo-independent eubacterial alternative nitrogenases and other methanogen nitrogenases. In this study, we cloned and sequenced nifD1 and part of nifK1 from M. barkeri 227. The deduced amino acid sequence encoded by nifD1 from M. barkeri showed great similarity with vnfD gene products from vanadium (V) nitrogenases, with an 80% identity at the amino acid level with the vnfD gene product from Anabaena variabilis. Moreover, there was a small open reading frame located between nifD1 and nifK1 with clear homology to vnfG, a hallmark of eubacterial alternative nitrogenases. Stimulation of diazotrophic growth of M. barkeri 227 by V in the absence of Mo was demonstrated. The unusual complement of nif genes in M. barkeri 227, with one cluster resembling that from a gram-positive eubacterium and the other resembling a eubacterial V nitrogenase gene cluster, suggests horizontal genetic transfer of those genes. PMID:10809706

  15. Microbiological and chemical characterization of hydrothermal fluids at Tortugas Mountain Geothermal Area, southern New Mexico, USA

    NASA Astrophysics Data System (ADS)

    Schulze-Makuch, Dirk; Kennedy, John F.

    2000-06-01

    The Tortugas Mountain Geothermal Area is part of the larger hydrothermal system of the Rio Grande Rift, southern New Mexico, USA. Chemical and microbial parameters indicate that the sampled hydrothermal water derives from a mixture zone of deep, anaerobic water with meteoric water from an adjacent alluvial, non-thermal groundwater flow system. A microbial phospholipid fatty acid (PLFA) analysis indicates that biomass and diversity of hydrothermal groundwater are very low, whereas hydrothermal surface water is diverse and bacteria are in a rapid growth phase. A nucleic acid (DNA) analysis of the hydrothermal groundwater resulted in the identification of one eubacterium and two Archaea (archaebacteria); the eubacterium and one Archaea were previously unknown. The one Archaea that could be related to a known species is an extreme halophilic methanomicrobacterium. The presence of the halophilic Archaea and the other Archaea species supports the hypothesis of the Tortugas Mountain Geothermal Area being the discharge area of deep circulating groundwater within a bedrock-hosted regional groundwater flow system.

  16. Agglutinins to bacteria in Crohn's disease.

    PubMed Central

    Matthews, N; Mayberry, J F; Rhodes, J; Neale, L; Munro, J; Wensinck, F; Lawson, G H; Rowland, A C; Berkhoff, G A; Barthold, S W

    1980-01-01

    Sera from patients with Crohn's disease were tested for antibodies against organisms which are thought to cause inflammatory bowel disease in animals, or have been implicated in human Crohn's disease. Control sera were collected from healthy individuals and patients with ulcerative colitis. Sera from Crohn's disease and controls failed to agglutinate Clostridium colinum or Campylobacter sputorum subsp. mucosalis and two strains of Mycobacterium paratuberculosis (M26 and M27). Most of the sera agglutinated a Citrobacter freundii variant, Mycobacterium paratuberculosis (M28) and Mycobacterium avium (M41) but Crohn's disease sera did not differ from controls. A complement fixation test against Chlamydia gave more positive reactions in patients with Crohn's disease and colitis than in healthy controls. There was a clear difference between the sera from patients with Crohn's disease and other sera, including ulcerative colitis, in agglutination tests with the commensal coccoid rods of the genera Eubacterium and Peptostreptococcus; in these tests 54% of sera from Crohn's disease were positive compared with 11% in ulcerative colitis and none of the sera from healthy controls. All the results were essentially negative with the exception of those from Eubacterium and Peptostreptococcus and these bacteria merit investigation. PMID:7429299

  17. The human genome retains relics of its prokaryotic ancestry: human genes of archaebacterial and eubacterial origin exhibit remarkable differences.

    PubMed

    Alvarez-Ponce, David; McInerney, James O

    2011-01-01

    Eukaryotes are generally thought to stem from a fusion event involving an archaebacterium and a eubacterium. As a result of this event, contemporaneous eukaryotic genomes are chimeras of genes inherited from both endosymbiotic partners. These two coexisting gene repertoires have been shown to differ in a number of ways in yeast. Here we combine genomic and functional data in order to determine if and how human genes that have been inherited from both prokaryotic ancestors remain distinguishable. We show that, despite being fewer in number, human genes of archaebacterial origin are more highly and broadly expressed across tissues, are more likely to have lethal mouse orthologs, tend to be involved in informational processes, are more selectively constrained, and encode shorter and more central proteins in the protein-protein interaction network than eubacterium-like genes. Furthermore, consistent with endosymbiotic theory, we show that proteins tend to interact with those encoded by genes of the same ancestry. Most interestingly from a human health perspective, archaebacterial genes are less likely to be involved in heritable human disease. Taken together, these results show that more than 2 billion years after eukaryogenesis, the human genome retains at least two somewhat distinct communities of genes. PMID:21795752

  18. Sugar phosphorylation activity in ruminal acetogens.

    PubMed

    Jiang, W; Pinder, R S; Patterson, J A; Ricke, S C

    2012-01-01

    Acetogenic bacteria Acetitomaculum ruminis, Acetobacterium woodii, and Eubacterium limosum were compared for phosphoenolpyruvate (PEP) and ATP-dependent phosphorylation of glucose and 2-deoxy-glucose. Rate of phosphorylation activity was measured in toluene-treated acetogenic cells using PEP and ATP and radiolabled glucose or 2-deoxy glucose. Eubacterium limosum, most likely has a glucose phosphotransferase system (PTS). In contrast, A. ruminis, and A. woodii had PEP-dependent glucose phosphorylation rates very similar to control rates, suggesting the lack of PTS activity. These results were confirmed by PEP dependent 2-deoxyglucose phosphorylation data. The rates of ATP-dependent glucose phosphorylation were higher than PEP-dependent glucose dependent in all organisms surveyed. Only E. limosum appeared to have PTS. The presence of PTS in E. limosum could explain why it is not capable of utilizing sugars and H(2)/CO(2) simultaneously and why acetogenesis is not as prominant in the rumen because of the availability of carbohydrates as alternative energy substrates. PMID:22423990

  19. The chimeric eukaryote: Origin of the nucleus from the karyomastigont in amitochondriate protists

    PubMed Central

    Margulis, Lynn; Dolan, Michael F.; Guerrero, Ricardo

    2000-01-01

    We present a testable model for the origin of the nucleus, the membrane-bounded organelle that defines eukaryotes. A chimeric cell evolved via symbiogenesis by syntrophic merger between an archaebacterium and a eubacterium. The archaebacterium, a thermoacidophil resembling extant Thermoplasma, generated hydrogen sulfide to protect the eubacterium, a heterotrophic swimmer comparable to Spirochaeta or Hollandina that oxidized sulfide to sulfur. Selection pressure for speed swimming and oxygen avoidance led to an ancient analogue of the extant cosmopolitan bacterial consortium “Thiodendron latens.” By eubacterial-archaebacterial genetic integration, the chimera, an amitochondriate heterotroph, evolved. This “earliest branching protist” that formed by permanent DNA recombination generated the nucleus as a component of the karyomastigont, an intracellular complex that assured genetic continuity of the former symbionts. The karyomastigont organellar system, common in extant amitochondriate protists as well as in presumed mitochondriate ancestors, minimally consists of a single nucleus, a single kinetosome and their protein connector. As predecessor of standard mitosis, the karyomastigont preceded free (unattached) nuclei. The nucleus evolved in karyomastigont ancestors by detachment at least five times (archamoebae, calonymphids, chlorophyte green algae, ciliates, foraminifera). This specific model of syntrophic chimeric fusion can be proved by sequence comparison of functional domains of motility proteins isolated from candidate taxa. PMID:10860956

  20. Genome Analysis of a New Rhodothermaceae Strain Isolated from a Hot Spring

    PubMed Central

    Goh, Kian Mau; Chan, Kok-Gan; Lim, Soon Wee; Liew, Kok Jun; Chan, Chia Sing; Shamsir, Mohd Shahir; Ee, Robson; Adrian, Tan-Guan-Sheng

    2016-01-01

    A bacterial strain, designated RA, was isolated from water sample of a hot spring on Langkawi Island of Malaysia using marine agar. Strain RA is an aerophilic and thermophilic microorganism that grows optimally at 50–60°C and is capable of growing in marine broth containing 1–10% (w/v) NaCl. 16S rRNA gene sequence analysis demonstrated that this strain is most closely related (<90% sequence identity) to Rhodothermaceae, which currently comprises of six genera: Rhodothermus (two species), Salinibacter (three species), Salisaeta (one species), Rubricoccus (one species), Rubrivirga (one species), and Longimonas (one species). Notably, analysis of average nucleotide identity (ANI) values indicated that strain RA may represent the first member of a novel genus of Rhodothermaceae. The draft genome of strain RA is 4,616,094 bp with 3630 protein-coding gene sequences. Its GC content is 68.3%, which is higher than that of most other genomes of Rhodothermaceae. Strain RA has genes for sulfate permease and arylsulfatase to withstand the high sulfur and sulfate contents of the hot spring. Putative genes encoding proteins involved in adaptation to osmotic stress were identified which encode proteins namely Na+/H+ antiporters, a sodium/solute symporter, a sodium/glutamate symporter, trehalose synthase, malto-oligosyltrehalose synthase, choline-sulfatase, potassium uptake proteins (TrkA and TrkH), osmotically inducible protein C, and the K+ channel histidine kinase KdpD. Furthermore, genome description of strain RA and comparative genome studies in relation to other related genera provide an overview of the uniqueness of this bacterium. PMID:27471502

  1. Structure of branching enzyme- and amylomaltase modified starch produced from well-defined amylose to amylopectin substrates.

    PubMed

    Sorndech, Waraporn; Sagnelli, Domenico; Meier, Sebastian; Jansson, Anita M; Lee, Byung-Hoo; Hamaker, Bruce R; Rolland-Sabaté, Agnès; Hebelstrup, Kim H; Tongta, Sunanta; Blennow, Andreas

    2016-11-01

    Thermostable branching enzyme (BE, EC 2.4.1.18) from Rhodothermus obamensis in combination with amylomaltase (AM, EC 2.4.1.25) from Thermus thermophilus was used to modify starch structure exploring potentials to extensively increase the number of branch points in starch. Amylose is an important constituent in starch and the effect of amylose on enzyme catalysis was investigated using amylose-only barley starch (AO) and waxy maize starch (WX) in well-defined ratios. All products were analysed for amylopectin chain length distribution, α-1,6 glucosidic linkages content, molar mass distribution and digestibility by using rat intestinal α-glucosidases. For each enzyme treatment series, increased AO content resulted in a higher rate of α-1,6 glucosidic linkage formation but as an effect of the very low initial branching of the AO, the final content of α-1,6 glucosidic linkages was slightly lower as compared to the high amylopectin substrates. However, an increase specifically in short chains was produced at high AO levels. The molar mass distribution for the enzyme treated samples was lower as compared with substrate WX and AO, indicating the presence of hydrolytic activity as well as cyclisation of the substrate. For all samples, increased amylose substrate showed decreased α- and β-amylolysis. Surprisingly, hydrolysis with rat intestinal α-glucosidases was higher with increasing α-1,6 glucosidic linkage content and decreasing M¯w indicating that steric hindrance towards the α-glucosidases was directed by the molar mass rather that the branching density of the glucan per se. Our data demonstrate that a higher amylose content in the substrate starch efficiently produces α-1,6 glucosidic linkages and that the present of amylose generates a higher M¯w and more resistant product than amylopectin. The combination of BE→AM→BE provided somewhat more resistant α-glucan products as compared to BE alone. PMID:27516249

  2. Pro-inflammatory flagellin proteins of prevalent motile commensal bacteria are variably abundant in the intestinal microbiome of elderly humans.

    PubMed

    Neville, B Anne; Sheridan, Paul O; Harris, Hugh M B; Coughlan, Simone; Flint, Harry J; Duncan, Sylvia H; Jeffery, Ian B; Claesson, Marcus J; Ross, R Paul; Scott, Karen P; O'Toole, Paul W

    2013-01-01

    Some Eubacterium and Roseburia species are among the most prevalent motile bacteria present in the intestinal microbiota of healthy adults. These flagellate species contribute "cell motility" category genes to the intestinal microbiome and flagellin proteins to the intestinal proteome. We reviewed and revised the annotation of motility genes in the genomes of six Eubacterium and Roseburia species that occur in the human intestinal microbiota and examined their respective locus organization by comparative genomics. Motility gene order was generally conserved across these loci. Five of these species harbored multiple genes for predicted flagellins. Flagellin proteins were isolated from R. inulinivorans strain A2-194 and from E. rectale strains A1-86 and M104/1. The amino-termini sequences of the R. inulinivorans and E. rectale A1-86 proteins were almost identical. These protein preparations stimulated secretion of interleukin-8 (IL-8) from human intestinal epithelial cell lines, suggesting that these flagellins were pro-inflammatory. Flagellins from the other four species were predicted to be pro-inflammatory on the basis of alignment to the consensus sequence of pro-inflammatory flagellins from the β- and γ- proteobacteria. Many fliC genes were deduced to be under the control of σ(28). The relative abundance of the target Eubacterium and Roseburia species varied across shotgun metagenomes from 27 elderly individuals. Genes involved in the flagellum biogenesis pathways of these species were variably abundant in these metagenomes, suggesting that the current depth of coverage used for metagenomic sequencing (3.13-4.79 Gb total sequence in our study) insufficiently captures the functional diversity of genomes present at low (≤1%) relative abundance. E. rectale and R. inulinivorans thus appear to synthesize complex flagella composed of flagellin proteins that stimulate IL-8 production. A greater depth of sequencing, improved evenness of sequencing and improved

  3. Pro-Inflammatory Flagellin Proteins of Prevalent Motile Commensal Bacteria Are Variably Abundant in the Intestinal Microbiome of Elderly Humans

    PubMed Central

    Neville, B. Anne; Sheridan, Paul O.; Harris, Hugh M. B.; Coughlan, Simone; Flint, Harry J.; Duncan, Sylvia H.; Jeffery, Ian B.; Claesson, Marcus J.; Ross, R. Paul; Scott, Karen P.; O'Toole, Paul W.

    2013-01-01

    Some Eubacterium and Roseburia species are among the most prevalent motile bacteria present in the intestinal microbiota of healthy adults. These flagellate species contribute “cell motility” category genes to the intestinal microbiome and flagellin proteins to the intestinal proteome. We reviewed and revised the annotation of motility genes in the genomes of six Eubacterium and Roseburia species that occur in the human intestinal microbiota and examined their respective locus organization by comparative genomics. Motility gene order was generally conserved across these loci. Five of these species harbored multiple genes for predicted flagellins. Flagellin proteins were isolated from R. inulinivorans strain A2-194 and from E. rectale strains A1-86 and M104/1. The amino-termini sequences of the R. inulinivorans and E. rectale A1-86 proteins were almost identical. These protein preparations stimulated secretion of interleukin-8 (IL-8) from human intestinal epithelial cell lines, suggesting that these flagellins were pro-inflammatory. Flagellins from the other four species were predicted to be pro-inflammatory on the basis of alignment to the consensus sequence of pro-inflammatory flagellins from the β- and γ- proteobacteria. Many fliC genes were deduced to be under the control of σ28. The relative abundance of the target Eubacterium and Roseburia species varied across shotgun metagenomes from 27 elderly individuals. Genes involved in the flagellum biogenesis pathways of these species were variably abundant in these metagenomes, suggesting that the current depth of coverage used for metagenomic sequencing (3.13–4.79 Gb total sequence in our study) insufficiently captures the functional diversity of genomes present at low (≤1%) relative abundance. E. rectale and R. inulinivorans thus appear to synthesize complex flagella composed of flagellin proteins that stimulate IL-8 production. A greater depth of sequencing, improved evenness of sequencing and improved

  4. The weak link: do muscle properties determine locomotor performance in frogs?

    PubMed

    Roberts, Thomas J; Abbott, Emily M; Azizi, Emanuel

    2011-05-27

    Muscles power movement, yet the conceptual link between muscle performance and locomotor performance is poorly developed. Frog jumping provides an ideal system to probe the relationship between muscle capacity and locomotor performance, because a jump is a single discrete event and mechanical power output is a critical determinant of jump distance. We tested the hypothesis that interspecific variation in jump performance could be explained by variability in available muscle power. We used force plate ergometry to measure power produced during jumping in Cuban tree frogs (Osteopilus septentrionalis), leopard frogs (Rana pipiens) and cane toads (Bufo marinus). We also measured peak isotonic power output in isolated plantaris muscles for each species. As expected, jump performance varied widely. Osteopilus septentrionalis developed peak power outputs of 1047.0 ± 119.7 W kg(-1) hindlimb muscle mass, about five times that of B. marinus (198.5 ± 54.5 W kg(-1)). Values for R. pipiens were intermediate (543.9 ± 96.2 W kg(-1)). These differences in jump power were not matched by differences in available muscle power, which were 312.7 ± 28.9, 321.8 ± 48.5 and 262.8 ± 23.2 W kg(-1) muscle mass for O. septentrionalis, R. pipiens and B. marinus, respectively. The lack of correlation between available muscle power and jump power suggests that non-muscular mechanisms (e.g. elastic energy storage) can obscure the link between muscle mechanical performance and locomotor performance. PMID:21502120

  5. Is Monoglucosyldiacylglycerol a Precursor to Monogalactosyldiacylglycerol in All Cyanobacteria?

    PubMed

    Sato, Naoki

    2015-10-01

    Monogalactosyldiacylglycerol (MGDG) is ubiquitous in the photosynthetic membranes of cyanobacteria and chloroplasts. It is synthesized by galactosylation of diacylglycerol (DAG) in the chloroplasts, whereas it is produced by epimerization of monoglucosyldiacylglycerol (GlcDG) in at least several cyanobacteria that have been analyzed such as Synechocystis sp. PCC 6803. A previous study, however, showed that the mgdE gene encoding the epimerase is absent in some cyanobacteria such as Gloeobacter violaceus, Thermosynechococcus elongatus and Acaryochloris marina. In addition, the N-terminal 'fatty acid hydroxylase' domain is lacking in the MgdE protein of Prochlorococcus marinus. These problems may cast doubt upon the general (or exclusive) role of MgdE in the epimerization of GlcDG to MGDG in cyanobacteria. In addition, GlcDG is usually present at a very low level, and the structural determination of endogenous GlcDG has not been accomplished with cyanobacterial samples. In this study, I determined the structure of GlcDG from Anabaena variabilis by (1)H- and (13)C-nuclear magnetic resonance (NMR) spectroscopy. I then showed that G. violaceus, T. elongatus, A. marina and P. marinus contain GlcDG. In all cases, GlcDG consisted of fewer unsaturated molecular species than MGDG, providing further evidence that GlcDG is a precursor to MGDG. The conversion of GlcDG to MGDG was also demonstrated by radiolabeling and chase experiments in G. violaceus and P. marinus. These results demonstrate that all the analyzed cyanobacteria contain GlcDG, which is converted to MGDG, and suggest that an alternative epimerase is required for MGDG synthesis in these cyanobacteria. PMID:26276824

  6. Landscape-Level Variation in Disease Susceptibility Related to Shallow-Water Hypoxia

    PubMed Central

    Breitburg, Denise L.; Hondorp, Darryl; Audemard, Corinne; Carnegie, Ryan B.; Burrell, Rebecca B.; Trice, Mark; Clark, Virginia

    2015-01-01

    Diel-cycling hypoxia is widespread in shallow portions of estuaries and lagoons, especially in systems with high nutrient loads resulting from human activities. Far less is known about the effects of this form of hypoxia than deeper-water seasonal or persistent low dissolved oxygen. We examined field patterns of diel-cycling hypoxia and used field and laboratory experiments to test its effects on acquisition and progression of Perkinsus marinus infections in the eastern oyster, Crassostrea virginica, as well as on oyster growth and filtration. P. marinus infections cause the disease known as Dermo, have been responsible for declines in oyster populations, and have limited success of oyster restoration efforts. The severity of diel-cycling hypoxia varied among shallow monitored sites in Chesapeake Bay, and average daily minimum dissolved oxygen was positively correlated with average daily minimum pH. In both field and laboratory experiments, diel-cycling hypoxia increased acquisition and progression of infections, with stronger results found for younger (1-year-old) than older (2-3-year-old) oysters, and more pronounced effects on both infections and growth found in the field than in the laboratory. Filtration by oysters was reduced during brief periods of exposure to severe hypoxia. This should have reduced exposure to waterborne P. marinus, and contributed to the negative relationship found between hypoxia frequency and oyster growth. Negative effects of hypoxia on the host immune response is, therefore, the likely mechanism leading to elevated infections in oysters exposed to hypoxia relative to control treatments. Because there is considerable spatial variation in the frequency and severity of hypoxia, diel-cycling hypoxia may contribute to landscape-level spatial variation in disease dynamics within and among estuarine systems. PMID:25671595

  7. Landscape-level variation in disease susceptibility related to shallow-water hypoxia.

    PubMed

    Breitburg, Denise L; Hondorp, Darryl; Audemard, Corinne; Carnegie, Ryan B; Burrell, Rebecca B; Trice, Mark; Clark, Virginia

    2015-01-01

    Diel-cycling hypoxia is widespread in shallow portions of estuaries and lagoons, especially in systems with high nutrient loads resulting from human activities. Far less is known about the effects of this form of hypoxia than deeper-water seasonal or persistent low dissolved oxygen. We examined field patterns of diel-cycling hypoxia and used field and laboratory experiments to test its effects on acquisition and progression of Perkinsus marinus infections in the eastern oyster, Crassostrea virginica, as well as on oyster growth and filtration. P. marinus infections cause the disease known as Dermo, have been responsible for declines in oyster populations, and have limited success of oyster restoration efforts. The severity of diel-cycling hypoxia varied among shallow monitored sites in Chesapeake Bay, and average daily minimum dissolved oxygen was positively correlated with average daily minimum pH. In both field and laboratory experiments, diel-cycling hypoxia increased acquisition and progression of infections, with stronger results found for younger (1-year-old) than older (2-3-year-old) oysters, and more pronounced effects on both infections and growth found in the field than in the laboratory. Filtration by oysters was reduced during brief periods of exposure to severe hypoxia. This should have reduced exposure to waterborne P. marinus, and contributed to the negative relationship found between hypoxia frequency and oyster growth. Negative effects of hypoxia on the host immune response is, therefore, the likely mechanism leading to elevated infections in oysters exposed to hypoxia relative to control treatments. Because there is considerable spatial variation in the frequency and severity of hypoxia, diel-cycling hypoxia may contribute to landscape-level spatial variation in disease dynamics within and among estuarine systems. PMID:25671595

  8. Spliced leader RNAs, mitochondrial gene frameshifts and multi-protein phylogeny expand support for the genus Perkinsus as a unique group of alveolates.

    PubMed

    Zhang, Huan; Campbell, David A; Sturm, Nancy R; Dungan, Christopher F; Lin, Senjie

    2011-01-01

    The genus Perkinsus occupies a precarious phylogenetic position. To gain a better understanding of the relationship between perkinsids, dinoflagellates and other alveolates, we analyzed the nuclear-encoded spliced-leader (SL) RNA and mitochondrial genes, intron prevalence, and multi-protein phylogenies. In contrast to the canonical 22-nt SL found in dinoflagellates (DinoSL), P. marinus has a shorter (21-nt) and a longer (22-nt) SL with slightly different sequences than DinoSL. The major SL RNA transcripts range in size between 80-83 nt in P. marinus, and ∼ 83 nt in P. chesapeaki, significantly larger than the typical ≤ 56-nt dinoflagellate SL RNA. In most of the phylogenetic trees based on 41 predicted protein sequences, P. marinus branched at the base of the dinoflagellate clade that included the ancient taxa Oxyrrhis and Amoebophrya, sister to the clade of apicomplexans, and in some cases clustered with apicomplexans as a sister to the dinoflagellate clade. Of 104 Perkinsus spp. genes examined 69.2% had introns, a higher intron prevalence than in dinoflagellates. Examination of Perkinsus spp. mitochondrial cytochrome B and cytochrome C oxidase subunit I genes and their cDNAs revealed no mRNA editing, but these transcripts can only be translated when frameshifts are introduced at every AGG and CCC codon as if AGGY codes for glycine and CCCCU for proline. These results, along with the presence of the numerous uncharacterized 'marine alveolate group I' and Perkinsus-like lineages separating perkinsids from core dinoflagellates, expand support for the affiliation of the genus Perkinsus with an independent lineage (Perkinsozoa) positioned between the phyla of Apicomplexa and Dinoflagellata. PMID:21629701

  9. The weak link: do muscle properties determine locomotor performance in frogs?

    PubMed Central

    Roberts, Thomas J.; Abbott, Emily M.; Azizi, Emanuel

    2011-01-01

    Muscles power movement, yet the conceptual link between muscle performance and locomotor performance is poorly developed. Frog jumping provides an ideal system to probe the relationship between muscle capacity and locomotor performance, because a jump is a single discrete event and mechanical power output is a critical determinant of jump distance. We tested the hypothesis that interspecific variation in jump performance could be explained by variability in available muscle power. We used force plate ergometry to measure power produced during jumping in Cuban tree frogs (Osteopilus septentrionalis), leopard frogs (Rana pipiens) and cane toads (Bufo marinus). We also measured peak isotonic power output in isolated plantaris muscles for each species. As expected, jump performance varied widely. Osteopilus septentrionalis developed peak power outputs of 1047.0 ± 119.7 W kg−1 hindlimb muscle mass, about five times that of B. marinus (198.5 ± 54.5 W kg−1). Values for R. pipiens were intermediate (543.9 ± 96.2 W kg−1). These differences in jump power were not matched by differences in available muscle power, which were 312.7 ± 28.9, 321.8 ± 48.5 and 262.8 ± 23.2 W kg−1 muscle mass for O. septentrionalis, R. pipiens and B. marinus, respectively. The lack of correlation between available muscle power and jump power suggests that non-muscular mechanisms (e.g. elastic energy storage) can obscure the link between muscle mechanical performance and locomotor performance. PMID:21502120

  10. Field application methods for recovery of the selective lampricide, 3-trifluoromethyl-4-nitrophenol

    USGS Publications Warehouse

    Billy, Thomas J.; Daniels, Stacy L.; Kempe, Lloyd L.; Beeton, Alfred M.

    1965-01-01

    Colorimetric methods are described for the detection of residues of the selective lampricide, 3-trifluoromethyl-4-nitrophenol (TFM), in natural waters and fish tissues. Solvent extraction and anion exchange were used to separate and concentrate the lampricide, and to reduce high background colors which often interfere with the determinations. Data from the Pentwater and Muskegon Rivers (Michigan) showed an exponential rate of disappearance of TFM from the water immediately after treatments to eradicate larvae of the sea lamprey (Petromyzon marinus). No TFM was recovered from fish exposed in their natural environment to low levels of the lampricide during treatment; residues were recovered, however, from fish exposed to high concentrations in the laboratory.

  11. Exposure to the lampricide 3-trifluoromethyl-4-nitrophenol results in increased expression of carbohydrate transporters in Saccharomyces cerevisiae.

    PubMed

    Hinkle, Karen L; Anderson, Chad C; Forkey, Blake; Griffin, Jacob; Cone, Kelsey; Vitzthum, Carl; Olsen, Darlene

    2016-07-01

    The lampricide 3-trifluoromethyl-4-nitrophenol (TFM) is used to control sea lamprey (Petromyzon marinus) populations in freshwater lakes. Although TFM can have sublethal and lethal effects, little is known about gene expression changes with TFM exposure. Microarray analysis was used to determine differential gene expression over 4 h of exposure in Saccharomyces cerevisiae. Among the most significantly up-regulated genes were regulators of carbohydrate transport, including HXT1, HXT3, HXT4, IMA5, MIG2, and YKR075C. Environ Toxicol Chem 2016;35:1727-1732. © 2015 SETAC. PMID:26606276

  12. Downstream migration of recently transformed sea lampreys before and after treatment of a Lake Michigan tributary with a lampricide

    USGS Publications Warehouse

    Hodges, John W.

    1972-01-01

    After the Pere Marquette River was treated with a lampricide in May 1964, the number of recently transformed sea lampreys (Petromyzon marinus) collected in the water-intake structure of a chemical plant near the mouth of the stream dropped 99.5%, from 13,913 (average for 1962-63 and 1963-64) to 76 (average for the next four migration seasons). Average length of the lampreys caught increased markedly after the treatment. In five of the six migration seasons, the catch of downstream migrants was higher in the fall than in the spring.

  13. Status Report of the Pacific Lamprey (Lampetra Trzdentata) in the Columbia River Basin.

    SciTech Connect

    Close, David A.; Parker, Blaine; James, gary

    1995-07-01

    The widespread decline of Pacific lamprey (Lampetra tridentata) in the Pacific Northwest, especially in the Columbia River system has led to concerns and questions from a number of regional agencies, Native American tribes, and the public. To address these concerns, new research efforts must focus on specific problems associated with this understudied species. The preservation and restoration of this species is critical for a number of reasons, including its importance to the tribes and its importance as an indicator of ecosystem health. Historically lamprey have been labeled a pest species due to the problems associated with the exotic sea lamprey, (Petromyzon marinus), invading the Great Lakes.

  14. Cribrihabitans neustonicus sp. nov., isolated from coastal surface seawater, and emended description of the genus Cribrihabitans Chen et al. 2014.

    PubMed

    Hameed, Asif; Shahina, Mariyam; Lin, Shih-Yao; Lai, Wei-An; Liu, You-Cheng; Hsu, Yi-Han; Young, Chiu-Chung

    2014-11-01

    A Gram-stain-negative, strictly aerobic, rod- or oval-shaped, motile, non-spore-forming bacterium, designated strain CC-AMHB-3(T), was isolated from coastal surface seawater off Hualien, Taiwan. The novel strain showed high pairwise 16S rRNA gene sequence similarities to Ruegeria mobilis NBRC 101030(T) (96.5%), Ruegeria scottomollicae LMG 24367(T) (96.4%), Phaeobacter aquaemixtae SSK6-1(T) (96.2%), Phaeobacter daeponensis TF-218(T) (96.2%), Cribrihabitans marinus CZ-AM5(T) (96.1%) and other species of the family Rhodobacteraceae (≤ 95.9%). However, strain CC-AMHB-3(T) formed a distinct phyletic lineage associated with C. marinus CZ-AM5(T) during phylogenetic analyses. The polar lipid profile of strain CC-AMHB-3(T) included major amounts of diphosphatidylglycerol, phosphatidylglycerol and phosphatidylcholine; moderate amounts of phosphatidylethanolamine, an unidentified aminolipid, an unidentified phospholipid and an unidentified lipid; and trace amounts of an unidentified lipid and an unidentified phospholipid, which was qualitatively almost in line with that of C. marinus CZ-AM5(T) but remarkably distinct as compared with the type species of the genera Ruegeria (Ruegeria atlantica JCM 21234(T)) and Phaeobacter (Phaeobacter gallaeciensis JCM 21319(T)). In line with the fatty acid profile of C. marinus CZ-AM5(T), the major (>5% of total) fatty acids of strain CC-AMHB-3(T) were C(18:1)ω7c and/or C(18:1)ω6c (summed feature 8), 11-methyl C(18:1)ω7c and C(16:0). The DNA G+C content was 66.7 mol%. Ubiquinone-10 (Q-10) was the sole respiratory quinone. Thus, based on the results of the polyphasic study presented here, strain CC-AMHB-3(T) is considered to represent a novel species of the genus Cribrihabitans, for which the name Cribrihabitans neustonicus sp. nov. is proposed; the type strain is CC-AMHB-3(T) ( = JCM 19537(T) =BCRC 80695(T)). In addition, an emended description of the genus Cribrihabitans is also proposed. PMID:25180090

  15. Evaluation of lamprey larvicides in the Big Garlic River and Saux Head Lake

    USGS Publications Warehouse

    Manion, Patrick J.

    1969-01-01

    Bayluscide (5,2'-dichloro-4'-nitrosalicylanilide) and TFM (3-trifluoromethyl-4-nitrophenol) were evaluated as selective larvicides for control of the sea lamprey, Petromyzon marinus, in the Big Garlic River and Saux Head Lake in Marquette County, Michigan. Population estimates and movement of ammocetes were determined from the recapture of marked ammocetes released before chemical treatment. In 1966 the estimated population of 3136 ammocetes off the stream mouth in Saux Head Lake was reduced 89% by treatment with granular Bayluscide; this percentage was supported by a population estimate of 120 ammocetes in 1967, an indicated reduction of 96% from 1966. Post-marking movement of ammocetes was greater upstream than downstream.

  16. An all-season trap for downstream-migrating fish and other aquatic organisms

    USGS Publications Warehouse

    McLain, Alberton; Manion, Patrick J.

    1967-01-01

    AN INVESTIGATION OF THE LARVAL STAGES OF THE SEA LAMPREY (Petromyzon marinus), which started in 1960, required a trap that could capture lamprey larvae moving downstream, and that would operate efficiently throughout the year. Sub zero temperatures in the winter and flooding during the spring were the most critical operational problems. Part of the trap was based on the principles of an inclined-plane trap described by Wolf (1951), but the design also incorporated features to prevent ice formation during the winter and to and to strain high flows during the spring runoff.

  17. Raccoon removal reduces sea turtle nest depredation in the Ten Thousand Islands of Florida

    USGS Publications Warehouse

    Garmestani, A.S.; Percival, H.F.

    2005-01-01

    Predation by raccoons, Procyon lotor marinus (L.), is the primary cause of sea turtle nest loss in the Ten Thousand Islands archipelago. Four islands within Ten Thousand Islands National Wildlife Refuge were surveyed for sea turtle nesting activity from 1991-95. Raccoons depredated 76-100% of nests on Panther Key from 1991-94, until 14 raccoons were removed in 1995 resulting in 0% depredation and 2 more were removed in 1996 resulting in 0% depredation. Raccoon removal may be an effective management option for increasing sea turtle nest survival on barrier islands.

  18. Host-parasite interactions: Marine bivalve molluscs and protozoan parasites, Perkinsus species.

    PubMed

    Soudant, Philippe; E Chu, Fu-Lin; Volety, Aswani

    2013-10-01

    This review assesses and examines the work conducted to date concerning host and parasite interactions between marine bivalve molluscs and protozoan parasites, belonging to Perkinsus species. The review focuses on two well-studied host-parasite interaction models: the two clam species, Ruditapes philippinarum and R. decussatus, and the parasite Perkinsus olseni, and the eastern oyster, Crassostrea virginica, and the parasite Perkinsus marinus. Cellular and humoral defense responses of the host in combating parasitic infection, the mechanisms (e.g., antioxidant enzymes, extracellular products) employed by the parasite in evading host defenses as well as the role of environmental factors in modulating the host-parasite interactions are described. PMID:23871855

  19. Fine structure of Perkinsus atlanticus n. sp. (Apicomplexa, Perkinsea) parasite of the clam Ruditapes decussatus from Portugal.

    PubMed

    Azevedo, C

    1989-08-01

    A new apicomplexan species, Perkinsus atlanticus, is described from gill filaments of the clam Ruditapes decussatus (Bivalvia) from Portugal, where it causes great mortality. The zoospores differ from those of other species of Perkinsus in size and shape, dimensions, insertion of the 2 flagella, and in the identity of the host. On the other hand, the life cycle stages showed some ultrastructural differences compared with Perkinsus marinus, the only species previously studied in detail. When the clams were parasitized heavily, ultrastructurally similar life cycle stages were found in foot and mantle tissues. PMID:2760774

  20. A radiative transfer model for remote sensing of laser induced fluorescence of phytoplankton in non-homogeneous turbid water

    NASA Technical Reports Server (NTRS)

    Venable, D. D.

    1980-01-01

    A radiative transfer computer model was developed to characterize the total flux of chlorophyll a fluoresced or backscattered photons when laser radiation is incident on turbid water that contains a non-homogeneous suspension of inorganic sediments and phytoplankton. The radiative transfer model is based on the Monte Carlo technique and assumes that: (1) the aquatic medium can be represented by a stratified concentration profile; and (2) that appropriate optical parameters can be defined for each layer. The model was designed to minimize the required computer resources and run time. Results are presented for an anacystis marinus culture.

  1. ANTIBIOTIC ACTIVITY OF MYXOBACTERIA IN RELATION TO THEIR BACTERIOLYTIC CAPACITY

    PubMed Central

    Norén, Börge; Raper, Kenneth B.

    1962-01-01

    Norén, Börge (University of Wisconsin, Madison) and Kenneth B. Raper. Antibiotic activity of myxobacteria in relation to their bacteriolytic capacity. J. Bacteriol. 84:157–162. 1962—Myxococcus virescens, M. fulvus, M. stipitatus, M. lacteus, Chondrococcus blasticus, and Chondromyces crocatus were tested for antibacterial activity, and all were found to secrete products that inhibited the growth of gram-positive eubacteria. The amount of inhibition varied with the myxobacterium employed and with the eubacterium used as a test organism. The growth of gram-negative eubacteria was in no case visibly affected by the antibiotic products. The experiments performed failed to indicate any positive relationship between the antibacterial activity and the bacteriolytic capacity of the six myxobacteria investigated. PMID:14480333

  2. Thermus thermophilus 16S rRNA is transcribed from an isolated transcription unit.

    PubMed Central

    Hartmann, R K; Erdmann, V A

    1989-01-01

    A cloned 16S rRNA gene from the extreme thermophilic eubacterium Thermus thermophilus HB8 was used to characterize the in vivo expression of the 16S rRNA genes in this organism by nuclease S1 mapping. The gene represents an isolated transcription unit encoding solely 16S rRNA. Under exponential growth conditions, transcription was initiated at a single promoter, which represents the structural equivalent of Escherichia coli rrn P2 promoters. The promoter-leader region was very similar to the E. coli rrn P2 promoter-leader segment that is responsible for antitermination. The T. thermophilus leader region was approximately 85 nucleotides shorter than its E. coli P2 counterpart. Potential processing intermediates were correlated with a proposed secondary structure of T. thermophilus pre-16S rRNA. Images PMID:2722737

  3. Ligand binding affinities of arctigenin and its demethylated metabolites to estrogen receptor alpha.

    PubMed

    Jin, Jong-Sik; Lee, Jong-Hyun; Hattori, Masao

    2013-01-01

    Phytoestrogens are defined as plant-derived compounds with estrogen-like activities according to their chemical structures and activities. Plant lignans are generally categorized as phytoestrogens. It was reported that (-)-arctigenin, the aglycone of arctiin, was demethylated to (-)-dihydroxyenterolactone (DHENL) by Eubacterium (E.) sp. ARC-2. Through stepwise demethylation, E. sp. ARC-2 produced six intermediates, three mono-desmethylarctigenins and three di-desmethylarctigenins. In the present study, ligand binding affinities of (-)-arctigenin and its seven metabolites, including DHENL, were investigated for an estrogen receptor alpha, and found that demethylated metabolites had stronger binding affinities than (-)-arctigenin using a ligand binding screen assay method. The IC(50) value of (2R,3R)-2-(4-hydroxy-3-methoxybenzyl)-3-(3,4-dihydroxybenzyl)-butyrolactone was 7.9 × 10⁻⁴ M. PMID:23325100

  4. Characterizing the Catalytic Potential of Deinococcus, Arthrobacter and other Robust Bacteria in Contaminated Subsurface Environments of the Hanford Site

    SciTech Connect

    Daly, Michael J.

    2006-05-01

    Ionizing Radiation (IR) Resistance in Bacteria. Until recently, there have been no clear physiologic predictors of a cell's ability to recover from ionizing radiation (IR) and other DOE-relevant oxidative stress conditions. In general, the most resistant bacteria have been Gram-positive (e.g., Deinococcus, Arthrobacter, Lactobacillus & Enterococcus spp.) and the most sensitive have been Gram-negative (e.g., Pseudomonas, Shewanella & Neisseria spp.). However, there are several reported exceptions to this paradigm, the Gram-negative cyanobacterium Chroococcidiopsis is extremely resistant to IR, whereas the Gram-positive Micrococcus luteus is sensitive. We have identified biomolecular signatures for radiation sensitivity and resistance which are independent of phylogeny, where very high and very low intracellular Mn/Fe concentration ratios correlated with very high and very low resistances, respectively; and restricting Mn(II) in the famously resistant Deinococcus radiodurans sensitized this eubacterium to IR.

  5. Characterizing the Catalytic Potential of Deinococcus, Arthrobacter and other Robust Bacteria in Contaminated Subsurface Environments of the Hanford Site

    SciTech Connect

    Fredrickson, Jim K.; Daly, Michael J.

    2006-06-01

    Until recently, there have been no clear physiologic predictors of a cell's ability to recover from ionizing radiation (IR), desiccation, and other DOE-relevant oxidative stress conditions. In general, the most resistant bacteria have been Gram-positive (e.g., Deinococcus, Arthrobacter, Lactobacillus & Enterococcus spp.) and the most sensitive have been Gram-negative (e.g., Pseudomonas, Shewanella & Neisseria spp.). However, there are several reported exceptions to this paradigm, the Gram-negative cyanobacterium Chroococcidiopsis is extremely resistant to IR, whereas the Gram-positive Micrococcus luteus is sensitive. We have identified biomolecular signatures for radiation sensitivity and resistance which are independent of phylogeny, where very high and very low intracellular Mn/Fe concentration ratios correlated with very high and very low resistances, respectively; and restricting Mn(II) in the famously resistant Deinococcus radiodurans sensitized this eubacterium to IR (http://cfyn.ifas.ufl.edu/radiation.pdf).

  6. Intestinal floras of populations that have a high risk of colon cancer.

    PubMed Central

    Moore, W E; Moore, L H

    1995-01-01

    The fecal floras of polyp patients, Japanese-Hawaiians, North American Caucasians, rural native Japanese, and rural native Africans were compared. The polyp patients and Japanese-Hawaiians were considered to be groups at high risk of colon cancer, and the rural native Japanese and rural native Africans were considered to be groups at low risk. The North American Caucasians were found to have a flora composition intermediate between these two groups. Fifteen bacterial taxa from the human fecal flora were significantly associated with high risk of colon cancer, and five were significantly associated with low risk of colon cancer. Total concentrations of Bacteroides species and, surprisingly, Bifidobacterium species were generally positively associated with increased risk of colon cancer. Some Lactobacillus species and Eubacterium aerofaciens, which also produces major amounts of lactic acid, showed closest associations with low risk of colon cancer. PMID:7574628

  7. Isolation of a bacterium that reductively dechlorinates tetrachloroethene to ethene

    SciTech Connect

    Maymo-Gatell, X.; Chien, Yueh-tyng; Zinder, S.H.

    1997-06-06

    Tetrachloroethene is a prominent groundwater pollutant that can be reductively dechlorinated by mixed anaerobic microbial populations to the nontoxic product ethene. Strain 195, a coccoid bacterium that dechlorinates tetrachlorethene to ethene, was isolated and characterized. Growth of strain 195 with H{sub 2} and tetrachloroethene as the electron donor and acceptor pair required extracts from mixed microbial cultures. Growth of strain 195 was resistant to ampicillin and vancomycin; its cell wall did not react with a peptidoglycan-specific lectin and its ultrastructure resembled S-layers of Archaea. Analysis of the 16S ribosomal DNA sequence of strain 195 indicated that it is a eubacterium without close affiliation to any known groups. 24 refs., 4 figs., 1 tab.

  8. Gut bacterial diversity of the tribes of India and comparison with the worldwide data.

    PubMed

    Dehingia, Madhusmita; Devi, Kanchal Thangjam; Talukdar, Narayan C; Talukdar, Rupjyoti; Reddy, Nageshwar; Mande, Sharmila S; Deka, Manab; Khan, Mojibur R

    2015-01-01

    The gut bacteria exert phenotypic traits to the host but the factors which determine the gut bacterial profile (GBP) is poorly understood. This study aimed to understand the effect of ethnicity and geography on GBP of Mongoloid and Proto-Australoid tribes of India. Fecal bacterial diversity was studied in fifteen tribal populations representing four geographic regions (Assam, Telangana, Manipur and Sikkim) by DGGE followed by NGS analysis on Illumina MiSeq platform. Geography and diet had significant effect on GBP of the Indian tribes which was dominated by Prevotella. The effects were more prominent with lower taxonomic levels, indicating probable functional redundancy of the core GBP. A comparison with the worldwide data revealed that GBP of the Indian population was similar to the Mongolian population (Mongolia). The bacterial genera Faecalibacterium, Eubacterium, Clostridium, Blautia, Ruminococcus and Roseburia were found to be core genera in the representative populations of the world. PMID:26689136

  9. Were the original eubacteria thermophiles?

    NASA Technical Reports Server (NTRS)

    Achenbach-Richter, L.; Gupta, R.; Stetter, K. O.; Woese, C. R.; Johnson, P. C. (Principal Investigator)

    1987-01-01

    Thermotoga maritima is one of the more unusual eubacteria: It is highly thermophilic, growing at temperatures higher than any other eubacterium; its cell wall appears to have a unique structure and its lipids a unique composition; and the organism is surrounded by a loose-fitting sheath of unknown function. Its phenotypic uniqueness is matched by its phylogenetic position; Thermotoga maritima represents the deepest known branching in the eubacterial line of descent, as measured by ribosomal RNA sequence comparisons. T. maritima also represents the most slowly evolving of eubacterial lineages. The fact that the two deepest branchings in the eubacterial line of descent (the other, the green non-sulfur bacteria and relatives, i.e. Chloroflexus, Thermomicrobium, etc.) are both basically thermophilic and slowly evolving, strongly suggests that all eubacteria have ultimately arisen from a thermophilic ancestor.

  10. Crystallization and preliminary X-ray study of a thermostable alanine racemase from Thermoanaerobacter tengcongensis MB4

    PubMed Central

    Dong, Hui; Xu, Shujing; Lu, Xiaoyun; He, Guangzheng; Zhao, Ranran; Chen, Shuai; Fu, Sheng; Ju, Jiansong

    2013-01-01

    Alanine racemase (AlrMB4), a dimeric PLP-dependent thermostable enzyme from the anaerobic eubacterium Thermoanaerobacter tengcongensis MB4, was expressed and purified with a His6 tag in a form suitable for X-ray crystallographic analysis. Crystals were grown by the hanging-drop vapour-diffusion method at 289 K using a solution consisting of 0.1 M bis-tris pH 7.0, 22%(w/v) polyethylene glycol 4000. X-ray diffraction data were collected to 2.6 Å resolution. The crystal belonged to the orthorhombic space group P212121, with two protein molecules in an asymmetric unit. PMID:23722847

  11. A chimeric prokaryotic ancestry of mitochondria and primitive eukaryotes.

    PubMed

    Karlin, S; Brocchieri, L; Mrázek, J; Campbell, A M; Spormann, A M

    1999-08-01

    We provide data and analysis to support the hypothesis that the ancestor of animal mitochondria (Mt) and many primitive amitochondrial (a-Mt) eukaryotes was a fusion microbe composed of a Clostridium-like eubacterium and a Sulfolobus-like archaebacterium. The analysis is based on several observations: (i) The genome signatures (dinucleotide relative abundance values) of Clostridium and Sulfolobus are compatible (sufficiently similar) and each has significantly more similarity in genome signatures with animal Mt sequences than do all other available prokaryotes. That stable fusions may require compatibility in genome signatures is suggested by the compatibility of plasmids and hosts. (ii) The expanded energy metabolism of the fusion organism was strongly selective for cementing such a fusion. (iii) The molecular apparatus of endospore formation in Clostridium serves as raw material for the development of the nucleus and cytoplasm of the eukaryotic cell. PMID:10430918

  12. Characteristics of enriched cultures for bio-huff-`n`-puff tests at Jilin oil field

    SciTech Connect

    Xiu-Yuan Wang; Gang Dai; Yan-Fen Xue; Shu-Hua Xie

    1995-12-31

    Three enriched cultures (48, 15a, and 26a), selected from more than 80 soil and water samples, could grow anaerobically in the presence of crude oil at 30{degrees}C and could ferment molasses to gases and organic acids. Oil recovery by culture 48 in the laboratory model experiment was enhanced by 25.2% over the original reserves and by 53.7% over the residual reserves. Enriched culture 48 was composed of at least 4 species belonging to the genera Eubacterium, Fusobacterium, and Bacteroides. This enriched culture was used as inoculum for MEOR field trials at Jilin oil field with satisfactory results. The importance of the role of these isolates in EOR was confirmed by their presence and behavior in the fluids produced from the microbiologically treated reservoir.

  13. Function and the biosynthesis of unusual corrinoids by a novel activation mechanism of aromatic compounds in anaerobic bacteria

    NASA Astrophysics Data System (ADS)

    Stupperich, E.; Eisinger, H. J.

    A corrinoid screening of several phylogenetically diverse ``archaebacteria'' revealed vitamin B12-like corrinoids. This indicates an optimized structure and function relationship of the corrinoids under different bacterial growth conditions during the early evolution of live. Some of these corrinoids have been substituted by modified corrinoids in growing cells without affecting the generation times of the bacteria. In this respect, the discovery of the unique para-cresolyl cobamide from the eubacterium Sporomusa ovata attracted attention. The unusual structure of this corrinoid was achieved by a biosynthesis proceeding via a novel and stereospecific activation mechanism of aromatic compounds. The corrinoid was detected both in the membrane fraction and in the soluble fraction of the cells. Methyltransfer is one of the probable functions of the para-cresolyl cobamide in Sporomusa.

  14. Biological and abiological sulfur reduction at high temperatures

    SciTech Connect

    Belkin, S.; Wirsen, C.O.; Jannasch, H.W.

    1985-05-01

    Reduction of elemental sulfur was studied in the presence and absence of thermophilic sulfur-reducing bacteria, at temperatures ranging from 65 to 110/sup 0/C, in anoxic artificial seawater media. Above 80/sup 0/C, significant amounts of sulfide were produced abiologically at linear rates, presumably by the disproportionation of sulfur. These rates increased with increasing temperature and pH and were enhanced by yeast extract. In the same medium, the sulfur respiration of two recent thermophilic isolates, a eubacterium and an archaebacterium, resulted in sulfide production at exponential rates. Although not essential for growth, sulfur increased the cell yield in both strains up to fourfold. It is suggested that sulfur respiration is favored at high temperatures and that this process is not limited to archaebacteria, but is shared by others extreme thermophiles.

  15. Structural basis for the interaction of antibiotics with peptidyl transferase center in eubacteria

    SciTech Connect

    Schlunzen, Frank; Zarivach, Raz; Harms, Jörg; Bashan, Anat; Tocilj, Ante; Albrecht, Renate; Yonath, Ada; Franceschi, Francois

    2009-10-07

    Ribosomes, the site of protein synthesis, are a major target for natural and synthetic antibiotics. Detailed knowledge of antibiotic binding sites is central to understanding the mechanisms of drug action. Conversely, drugs are excellent tools for studying the ribosome function. To elucidate the structural basis of ribosome-antibiotic interactions, we determined the high-resolution X-ray structures of the 50S ribosomal subunit of the eubacterium Deinococcus radiodurans, complexed with the clinically relevant antibiotics chloramphenicol, clindamycin and the three macrolides erythromycin, clarithromycin and roxithromycin. We found that antibiotic binding sites are composed exclusively of segments of 23S ribosomal RNA at the peptidyl transferase cavity and do not involve any interaction of the drugs with ribosomal proteins. Here we report the details of antibiotic interactions with the components of their binding sites. Our results also show the importance of putative Mg{sup +2} ions for the binding of some drugs. This structural analysis should facilitate rational drug design.

  16. Methanogenesis from acetate: a nonmethanogenic bacterium from an anaerobic acetate enrichment.

    PubMed

    Ward, D M; Mah, R A; Kaplan, I R

    1978-06-01

    A methanogenic acetate enrichment was initiated by inoculation of an acetate-mineral salts medium with domestic anaerobic digestor sludge and maintained by weekly transfer for 2 years. The enrichment culture contained a Methanosarcina and several obligately anaerobic nonmethanogenic bacteria. These latter organisms formed varying degrees of association with the Methanosarcina, ranging from the nutritionally fastidious gram-negative rod called the satellite bacterium to the nutritionally nonfastidious Eubacterium limosum. The satellite bacterium had growth requirements for amino acids, a peptide, a purine base, vitamin B12, and other B vitamins. Glucose, mannitol, starch, pyruvate, cysteine, lysine, leucine, isoleucine, arginine, and asparagine stimulated growth and hydrogen production. Acetate was neither incorporated nor metabolized by the satellite organism. Since acetate was the sole organic carbon source in the enrichment culture, organism(s) which metabolize acetate (such as the Methanosarcina) must produce substrates and growth factors for associated organisms which do not metabolize acetate. PMID:677881

  17. Structural reconstruction of the catalytic center of LiPDF through multiple scattering calculation with MXAN

    NASA Astrophysics Data System (ADS)

    Guo, Xiaoyun; Chu, Wangsheng; Ma, Sixuan; Gong, Weimin; Benfatto, Maurizio; Hu, Tiandou; Xie, Yaning; Wu, ZiYu

    2006-11-01

    Peptide deformylase (PDF, EC 3.5.1.27) is essential for the normal growth of eubacterium but not for mammalians. Recently, PDF has been studied as a target for new antibiotics. In this paper, X-ray absorption spectroscopy was employed to determine the local structure around the zinc ion of PDF from Leptospira Interrogans in dry powder, because it is very difficult to obtain the crystallized sample of LiPDF. We performed X-ray absorption near edge structure (XANES) calculation and reconstructed successfully the local geometry of the active center, and the results from calculations show that a water molecule (Wat1) has moved towards the zinc ion and lies in the distance range to coordinate with the zinc ion weakly. In addition, the sensitivity of theoretical spectra to the different ligand bodies was evaluated in terms of goodness-of-fit.

  18. Essential oil composition and antimicrobial activity of Angelica archangelica L. (Apiaceae) roots.

    PubMed

    Fraternale, Daniele; Flamini, Guido; Ricci, Donata

    2014-09-01

    In this paper, the chemical composition and the antimicrobial activity of the essential oil of Angelica archangelica L. (Apiaceae) roots from central Italy were analyzed. The major constituents of the oil were α-pinene (21.3%), δ-3-carene (16.5%), limonene (16.4%) and α-phellandrene (8.7%). The oil shows a good antimicrobial activity against Clostridium difficile, Clostridium perfringens, Enterococcus faecalis, Eubacterium limosum, Peptostreptococcus anaerobius, and Candida albicans with minimum inhibitory concentration (MIC) values of 0.25, 0.25, 0.13, 0.25, 2.25, and 0.50% v/v, respectively. A weaker antimicrobial activity against bifidobacteria and lactobacilli-very useful in the intestinal microflora-has also been shown with MIC values >4.0% v/v. PMID:24788027

  19. Gut bacterial diversity of the tribes of India and comparison with the worldwide data

    PubMed Central

    Dehingia, Madhusmita; Thangjam devi, Kanchal; Talukdar, Narayan C.; Talukdar, Rupjyoti; Reddy, Nageshwar; Mande, Sharmila S.; Deka, Manab; Khan, Mojibur R.

    2015-01-01

    The gut bacteria exert phenotypic traits to the host but the factors which determine the gut bacterial profile (GBP) is poorly understood. This study aimed to understand the effect of ethnicity and geography on GBP of Mongoloid and Proto-Australoid tribes of India. Fecal bacterial diversity was studied in fifteen tribal populations representing four geographic regions (Assam, Telangana, Manipur and Sikkim) by DGGE followed by NGS analysis on Illumina MiSeq platform. Geography and diet had significant effect on GBP of the Indian tribes which was dominated by Prevotella. The effects were more prominent with lower taxonomic levels, indicating probable functional redundancy of the core GBP. A comparison with the worldwide data revealed that GBP of the Indian population was similar to the Mongolian population (Mongolia). The bacterial genera Faecalibacterium, Eubacterium, Clostridium, Blautia, Ruminococcus and Roseburia were found to be core genera in the representative populations of the world. PMID:26689136

  20. Cytoskeletal elements in the bacterium Mycoplasma pneumoniae

    NASA Astrophysics Data System (ADS)

    Hegermann, Jan; Herrmann, Richard; Mayer, Frank

    2002-09-01

    Mycoplasma pneumoniae is a pathogenic eubacterium lacking a cell wall. Three decades ago, a "rod", an intracellular cytoskeletal structure, was discovered that was assumed to define and stabilize the elongated cell shape. Later, by treatment with detergent, a "Triton shell" (i.e. a fraction of detergent-insoluble cell material) could be obtained, believed to contain additional cytoskeletal elements. Now, by application of a modified Triton X-100 treatment, we are able to demonstrate that M. pneumoniae possesses a cytoskeleton consisting of a blade-like rod and a peripheral lining located close to the inner face of the cytoplasmic membrane, exhibiting features of a highly regular network. Attached "stalks" may support the cytoplasmic membrane. The rod was connected to the cell periphery by "spokes" and showed a defined ultrastructure. Its proximal end was found to be attached to a wheel-like complex. Fibrils extended from the proximal end of the rod into the cytoplasm.

  1. Effect of chito-oligosaccharides over human faecal microbiota during fermentation in batch cultures.

    PubMed

    Mateos-Aparicio, Inmaculada; Mengíbar, Marian; Heras, Angeles

    2016-02-10

    Chitosan with high number of deacetylated units, its reacetylated derivative and COS obtained through an enzymatic treatment with chitosanase were tested in pH controlled batch cultures to investigate the ability of the human faecal microbiota to utilise them. Chitosan derivatives with high number of deacetylated units decreased the bacterial populations: Bifidobacterium spp., Eubacterium rectale/Clostridium coccoides, C. Histolyticum and Bacteroides/Prevotella. On the other hand, chitosan derivatives with high content of acetylated residues maintained the tested bacterial groups and could increase Lactobacillus/Enterococcus. Regarding short chain fatty acids (SCFA), only low Mw COS increased the production in similar levels than fructo-oligossacharides (FOS). The acetylated chitosans and their COS do not appear as potential prebiotics but did not affect negatively the faecal microbiota, while derivatives with high number of deacetylated units could induce a colonic microbiota imbalance. PMID:26686171

  2. Biochemical characterization of thermostable ω-transaminase from Sphaerobacter thermophilus and its application for producing aromatic β- and γ-amino acids.

    PubMed

    Mathew, Sam; Nadarajan, Saravanan Prabhu; Chung, Taeowan; Park, Hyun Ho; Yun, Hyungdon

    2016-06-01

    An (S)-ω-transaminase from the thermophilic eubacterium Sphaerobacter thermophilus was expressed and functionally characterized. The enzyme showed good stability at high temperature and in the presence of various substrates. Substrate specificity analysis showed that the enzyme had activity towards a broad range of substrates including amines, β- and γ-amino acids. The purified enzyme showed a specific activity of 3.3U/mg towards rac-β-phenylalanine at 37°C. The applicability of this enzyme as an attractive biocatalyst was demonstrated by synthesizing optically pure β- and γ-amino acids. Among the various beta and gamma amino acids produced via asymmetric synthesis, (S)-4-amino-4-(4-methoxyphenyl)-butanoic acid showed highest analytical yield (82%) with excellent enantiomeric excess (>99%). PMID:27178795

  3. Direct Monitoring of β-Sheet Formation in the Outer Membrane Protein TtoA Assisted by TtOmp85.

    PubMed

    Henke, Katharina; Welte, Wolfram; Hauser, Karin

    2016-08-01

    Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy was applied to investigate the folding of an outer membrane protein, TtoA, assisted by TtOmp85, both from the thermophilic eubacterium Thermus thermophilus. To directly monitor the formation of β-sheet structure in TtoA and to analyze the function of TtOmp85, we immobilized unfolded TtoA on an ATR crystal. Interaction with TtOmp85 initiated TtoA folding as shown by time-dependent spectra recorded during the folding process. Our ATR-FTIR experiments prove that TtOmp85 possesses specific functionality to assist β-sheet formation of TtoA. We demonstrate the potential of this spectroscopic approach to study the interaction of outer membrane proteins in vitro and in a time-resolved manner. PMID:27400268

  4. Immobilization of Bacillus acidocaldarius whole-cell rhodanese in polysaccharide and insolubilized gelatin gels

    SciTech Connect

    De Riso, L.; Alteriis, E. de; Parascandola, P. |; La Cara, F.; Sada, A.

    1996-04-01

    The presence of rhodanese activity has been investigated in two strains of thermophilic eubacteria and two strains of extremophiles. Bacillus acidocaldarius, a thermoacidophilic eubacterium, showed the highest levels of enzyme activity. Whole cells, previously subjected to one cycle of freeze-thawing, were immobilized by entrapment in the polysaccharide matrices Ca-alginate, {kappa}-carrageenan and chitosan, and in an insolubilized gelatin gel. The results obtained with the different immobilizates in terms of activity yield, possibility of regeneration and operative stability were evaluated with the aim of setting up a continuous system. This was achieved with a system consisting of B. acidocaldarius cells entrapped in an insolubilized gelatin matrix. The latter, in the form of a thin membrane, was employed in a custom-conceived reactor operating as a plug flow reactor. 21 refs., 3 figs., 2 tabs.

  5. Butyrivibrio hungatei sp. nov. and Pseudobutyrivibrio xylanivorans sp. nov., butyrate-producing bacteria from the rumen.

    PubMed

    Kopecný, Jan; Zorec, Masa; Mrázek, Jakub; Kobayashi, Yasuo; Marinsek-Logar, Romana

    2003-01-01

    Two novel Gram-negative, anaerobic, non-spore-forming, butyrate-producing bacterial species, strains Mz 5T and JK 615T, were isolated from the rumen fluid of cow and sheep. Both strains were curved rods that were motile by means of single polar or subpolar flagellum and common in the rumen microbial ecosystem. Strain Mz 5T produced high xylanase, proteinase, pectin hydrolase and DNase activities; 1,4-beta-endoglucanase was also detected in the culture medium. The bacterium utilized a wide range of carbohydrates. Glucose was fermented to formate, butyrate, lactate, succinate and ethanol. The DNA G + C content was 42.1 mol%. The complete 16S rDNA sequence was obtained and phylogenetic relationships were determined. Strain Mz 5T and related isolates were located in clostridial cluster XIVa and were closely related to Pseudobutyrivibrio ruminis, Butyrivibrio crossotus, Roseburia cecicola and Eubacterium rectale. The name proposed for this novel bacterium is Pseudobutyrivibrio xylanivorans; the type strain is Mz 5T (=DSM 14809T =ATCC BAA-455T). Strain JK 615T produced no fibrolytic activity, but utilized a wide range of carbohydrates. Glucose was fermented to formate, acetate, butyrate and ethanol. The DNA G + C content was 44-8 mol%. The complete 16S rDNA sequence was obtained and phylogenetic relationships were determined. Strain JK 615T was located in clostridial cluster XIVa and was closely related to Clostridium proteoclasticum, Butyrivibrio fibrisolvens and Eubacterium halii. The name proposed for this novel bacterium is Butyrivibrio hungatei; the type strain is JK 615T (=DSM 14810T =ATCC BAA-456T). PMID:12656174

  6. Gut microbiome composition is linked to whole grain-induced immunological improvements

    PubMed Central

    Martínez, Inés; Lattimer, James M; Hubach, Kelcie L; Case, Jennifer A; Yang, Junyi; Weber, Casey G; Louk, Julie A; Rose, Devin J; Kyureghian, Gayaneh; Peterson, Daniel A; Haub, Mark D; Walter, Jens

    2013-01-01

    The involvement of the gut microbiota in metabolic disorders, and the ability of whole grains to affect both host metabolism and gut microbial ecology, suggest that some benefits of whole grains are mediated through their effects on the gut microbiome. Nutritional studies that assess the effect of whole grains on both the gut microbiome and human physiology are needed. We conducted a randomized cross-over trial with four-week treatments in which 28 healthy humans consumed a daily dose of 60 g of whole-grain barley (WGB), brown rice (BR), or an equal mixture of the two (BR+WGB), and characterized their impact on fecal microbial ecology and blood markers of inflammation, glucose and lipid metabolism. All treatments increased microbial diversity, the Firmicutes/Bacteroidetes ratio, and the abundance of the genus Blautia in fecal samples. The inclusion of WGB enriched the genera Roseburia, Bifidobacterium and Dialister, and the species Eubacterium rectale, Roseburia faecis and Roseburia intestinalis. Whole grains, and especially the BR+WGB treatment, reduced plasma interleukin-6 (IL-6) and peak postprandial glucose. Shifts in the abundance of Eubacterium rectale were associated with changes in the glucose and insulin postprandial response. Interestingly, subjects with greater improvements in IL-6 levels harbored significantly higher proportions of Dialister and lower abundance of Coriobacteriaceae. In conclusion, this study revealed that a short-term intake of whole grains induced compositional alterations of the gut microbiota that coincided with improvements in host physiological measures related to metabolic dysfunctions in humans. PMID:23038174

  7. Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Allelic Variants Relate to Shifts in Faecal Microbiota of Cystic Fibrosis Patients

    PubMed Central

    Santangelo, Floriana; Gagliardi, Antonella; De Biase, Riccardo Valerio; Stamato, Antonella; Bertasi, Serenella; Lucarelli, Marco

    2013-01-01

    Introduction In this study we investigated the effects of the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene variants on the composition of faecal microbiota, in patients affected by Cystic Fibrosis (CF). CFTR mutations (F508del is the most common) lead to a decreased secretion of chloride/water, and to mucus sticky secretions, in pancreas, respiratory and gastrointestinal tracts. Intestinal manifestations are underestimated in CF, leading to ileum meconium at birth, or small bowel bacterial overgrowth in adult age. Methods Thirty-six CF patients, fasting and under no-antibiotic treatment, were CFTR genotyped on both alleles. Faecal samples were subjected to molecular microbial profiling through Temporal Temperature Gradient Electrophoresis and species-specific PCR. Ecological parameters and multivariate algorithms were employed to find out if CFTR variants could be related to the microbiota structure. Results Patients were classified by two different criteria: 1) presence/absence of F508del mutation; 2) disease severity in heterozygous and homozygous F508del patients. We found that homozygous-F508del and severe CF patients exhibited an enhanced dysbiotic faecal microbiota composition, even within the CF cohort itself, with higher biodiversity and evenness. We also found, by species-specific PCR, that potentially harmful species (Escherichia coli and Eubacterium biforme) were abundant in homozygous-F508del and severe CF patients, while beneficial species (Faecalibacterium prausnitzii, Bifidobacterium spp., and Eubacterium limosum) were reduced. Conclusions This is the first report that establishes a link among CFTR variants and shifts in faecal microbiota, opening the way to studies that perceive CF as a ‘systemic disease’, linking the lung and the gut in a joined axis. PMID:23613805

  8. Detection of Ehrlichia spp., Anaplasma spp., Rickettsia spp., and Other Eubacteria in Ticks from the Thai-Myanmar Border and Vietnam

    PubMed Central

    Parola, Philippe; Cornet, Jean-Paul; Sanogo, Yibayiri Osée; Miller, R. Scott; Thien, Huynh Van; Gonzalez, Jean-Paul; Raoult, Didier; Telford III, Sam R.; Wongsrichanalai, Chansuda

    2003-01-01

    A total of 650 ticks, including 13 species from five genera, were collected from animals, from people, or by flagging of the vegetation at sites on the Thai-Myanmar border and in Vietnam. They were tested by PCR to detect DNA of bacteria of the order Rickettsiales. Three Anaplasma spp. were detected in ticks collected in Thailand, including (i) Anaplasma sp. strain AnDa465, which was considered a genotype of Anaplasma platys (formerly Ehrlichia platys) and which was obtained from Dermacentor auratus ticks collected from dogs; (ii) Anaplasma sp. strain AnAj360, which was obtained from Amblyomma javanense ticks collected on a pangolin; and (iii) Anaplasma sp. strain AnHl446, which was closely related to Anaplasma bovis and which was detected in Haemaphysalis lagrangei ticks collected from a bear. Three Ehrlichia spp. were identified, including (i) Ehrlichia sp. strain EBm52, which was obtained from Boophilus microplus ticks collected from cattle from Thailand; (ii) Ehrlichia sp. strain EHh324, which was closely related to Ehrlichia chaffeensis and which was detected in Haemaphysalis hystricis ticks collected from wild pigs in Vietnam; and (iii) Ehrlichia sp. strain EHh317, which was closely related to Ehrlichia sp. strain EBm52 and which was also detected in H. hystricis ticks collected from wild pigs in Vietnam. Two Rickettsia spp. were detected in Thailand, including (i) Rickettsia sp. strain RDla420, which was detected in Dermacentor auratus ticks collected from a bear, and (ii) Rickettsia sp. strain RDla440, which was identified from two pools of Dermacentor larvae collected from a wild pig nest. Finally, two bacteria named Eubacterium sp. strain Hw124 and Eubacterium sp. strain Hw191 were identified in Haemaphysalis wellingtoni ticks collected from chicken in Thailand; these strains could belong to a new group of bacteria. PMID:12682151

  9. Detection of Ehrlichia spp., Anaplasma spp., Rickettsia spp., and other eubacteria in ticks from the Thai-Myanmar border and Vietnam.

    PubMed

    Parola, Philippe; Cornet, Jean-Paul; Sanogo, Yibayiri Osée; Miller, R Scott; Thien, Huynh Van; Gonzalez, Jean-Paul; Raoult, Didier; Telford III, Sam R; Wongsrichanalai, Chansuda

    2003-04-01

    A total of 650 ticks, including 13 species from five genera, were collected from animals, from people, or by flagging of the vegetation at sites on the Thai-Myanmar border and in Vietnam. They were tested by PCR to detect DNA of bacteria of the order RICKETTSIALES: Three Anaplasma spp. were detected in ticks collected in Thailand, including (i) Anaplasma sp. strain AnDa465, which was considered a genotype of Anaplasma platys (formerly Ehrlichia platys) and which was obtained from Dermacentor auratus ticks collected from dogs; (ii) Anaplasma sp. strain AnAj360, which was obtained from Amblyomma javanense ticks collected on a pangolin; and (iii) Anaplasma sp. strain AnHl446, which was closely related to Anaplasma bovis and which was detected in Haemaphysalis lagrangei ticks collected from a bear. Three Ehrlichia spp. were identified, including (i) Ehrlichia sp. strain EBm52, which was obtained from Boophilus microplus ticks collected from cattle from Thailand; (ii) Ehrlichia sp. strain EHh324, which was closely related to Ehrlichia chaffeensis and which was detected in Haemaphysalis hystricis ticks collected from wild pigs in Vietnam; and (iii) Ehrlichia sp. strain EHh317, which was closely related to Ehrlichia sp. strain EBm52 and which was also detected in H. hystricis ticks collected from wild pigs in Vietnam. Two Rickettsia spp. were detected in Thailand, including (i) Rickettsia sp. strain RDla420, which was detected in Dermacentor auratus ticks collected from a bear, and (ii) Rickettsia sp. strain RDla440, which was identified from two pools of Dermacentor larvae collected from a wild pig nest. Finally, two bacteria named Eubacterium sp. strain Hw124 and Eubacterium sp. strain Hw191 were identified in Haemaphysalis wellingtoni ticks collected from chicken in Thailand; these strains could belong to a new group of bacteria. PMID:12682151

  10. Cytokine Response after Stimulation with Key Commensal Bacteria Differ in Post-Infectious Irritable Bowel Syndrome (PI-IBS) Patients Compared to Healthy Controls

    PubMed Central

    Sundin, Johanna; Rangel, Ignacio; Repsilber, Dirk; Brummer, Robert-Jan

    2015-01-01

    Background Microbial dysbiosis and prolonged immune activation resulting in low-grade inflammation and intestinal barrier dysfunction have been suggested to be underlying causes of post-infectious irritable bowel syndrome (PI-IBS). The aim of this study was to evaluate the difference in cytokine response between mucosal specimens of PI-IBS patients and healthy controls (HC) after ex vivo stimulation with key anaerobic bacteria. Methods Colonic biopsies from 11 PI-IBS patients and 10 HC were stimulated ex vivo with the commensal bacteria Bacteroides ovatus, Ruminococcus gnavus, Akkermansia muciniphila, Subdoligranulum variabile and Eubacterium limosum, respectively. The cytokine release (IL-1β, IL-2, IL-8, IL-10, IL-13, IL-17, TNF-α and IFN-γ) in stimulation supernatants was analyzed using the LUMINEX assay. Comparison of cytokine release between PI-IBS patients and healthy controls was performed taking both unstimulated and bacterially stimulated mucosal specimens into account. Key Results IL-13 release from mucosal specimens without bacterial stimulation was significantly lower in PI-IBS patients compared to HC (p < 0.05). After stimulation with Subdoligranulum variabile, IL-1β release from PI-IBS patients was significantly increased compared to HC (p < 0.05). Stimulation with Eubacterium limosum resulted in a significantly decreased IL-10 release in HC compared to PI-IBS patients (p < 0.05) and a tendency to decreased IL-13 release in HC compared to PI-IBS patients (p = 0.07). Conclusions & Inferences PI-IBS patients differ from HC with regard to cytokine release ex vivo after stimulation with selected commensal bacteria. Hence, our results support that the pathogenesis of PI-IBS comprises an altered immune response against commensal gut microbes. PMID:26366730

  11. TLR4, NOD1 and NOD2 mediate immune recognition of putative newly identified periodontal pathogens.

    PubMed

    Marchesan, J; Jiao, Y Z; Schaff, R A; Hao, J; Morelli, T; Kinney, J S; Gerow, E; Sheridan, R; Rodrigues, V; Paster, B J; Inohara, N; Giannobile, W V

    2016-06-01

    Periodontitis is a polymicrobial inflammatory disease that results from the interaction between the oral microbiota and the host immunity. Although the innate immune response is important for disease initiation and progression, the innate immune receptors that recognize both classical and putative periodontal pathogens that elicit an immune response have not been elucidated. By using the Human Oral Microbe Identification Microarray (HOMIM), we identified multiple predominant oral bacterial species in human plaque biofilm that strongly associate with severe periodontitis. Ten of the identified species were evaluated in greater depth, six being classical pathogens and four putative novel pathogens. Using human peripheral blood monocytes (HPBM) and murine bone-marrow-derived macrophages (BMDM) from wild-type (WT) and Toll-like receptor (TLR)-specific and MyD88 knockouts (KOs), we demonstrated that heat-killed Campylobacter concisus, Campylobacter rectus, Selenomonas infelix, Porphyromonas endodontalis, Porphyromonas gingivalis, and Tannerella forsythia mediate high immunostimulatory activity. Campylobacter concisus, C. rectus, and S. infelix exhibited robust TLR4 stimulatory activity. Studies using mesothelial cells from WT and NOD1-specific KOs and NOD2-expressing human embryonic kidney cells demonstrated that Eubacterium saphenum, Eubacterium nodatum and Filifactor alocis exhibit robust NOD1 stimulatory activity, and that Porphyromonas endodontalis and Parvimonas micra have the highest NOD2 stimulatory activity. These studies allowed us to provide important evidence on newly identified putative pathogens in periodontal disease pathogenesis showing that these bacteria exhibit different immunostimulatory activity via TLR4, NOD1, and NOD2 (Clinicaltrials.gov NCT01154855). PMID:26177212

  12. A Complete Sequence of the T. tengcongensis Genome

    PubMed Central

    Bao, Qiyu; Tian, Yuqing; Li, Wei; Xu, Zuyuan; Xuan, Zhenyu; Hu, Songnian; Dong, Wei; Yang, Jian; Chen, Yanjiong; Xue, Yanfen; Xu, Yi; Lai, Xiaoqin; Huang, Li; Dong, Xiuzhu; Ma, Yanhe; Ling, Lunjiang; Tan, Huarong; Chen, Runsheng; Wang, Jian; Yu, Jun; Yang, Huanming

    2002-01-01

    Thermoanaerobacter tengcongensis is a rod-shaped, gram-negative, anaerobic eubacterium that was isolated from a freshwater hot spring in Tengchong, China. Using a whole-genome-shotgun method, we sequenced its 2,689,445-bp genome from an isolate, MB4T (Genbank accession no. AE008691). The genome encodes 2588 predicted coding sequences (CDS). Among them, 1764 (68.2%) are classified according to homology to other documented proteins, and the rest, 824 CDS (31.8%), are functionally unknown. One of the interesting features of the T. tengcongensis genome is that 86.7% of its genes are encoded on the leading strand of DNA replication. Based on protein sequence similarity, the T. tengcongensis genome is most similar to that of Bacillus halodurans, a mesophilic eubacterium, among all fully sequenced prokaryotic genomes up to date. Computational analysis on genes involved in basic metabolic pathways supports the experimental discovery that T. tengcongensis metabolizes sugars as principal energy and carbon source and utilizes thiosulfate and element sulfur, but not sulfate, as electron acceptors. T. tengcongensis, as a gram-negative rod by empirical definitions (such as staining), shares many genes that are characteristics of gram-positive bacteria whereas it is missing molecular components unique to gram-negative bacteria. A strong correlation between the G + C content of tDNA and rDNA genes and the optimal growth temperature is found among the sequenced thermophiles. It is concluded that thermophiles are a biologically and phylogenetically divergent group of prokaryotes that have converged to sustain extreme environmental conditions over evolutionary timescale. [Supplemental material is available online at http://www.genome.org.] PMID:11997336

  13. Specialized Hydrocarbonoclastic Bacteria Prevailing in Seawater around a Port in the Strait of Malacca.

    PubMed

    Teramoto, Maki; Queck, Shu Yeong; Ohnishi, Kouhei

    2013-01-01

    Major degraders of petroleum hydrocarbons in tropical seas have been indicated only by laboratory culturing and never through observing the bacterial community structure in actual environments. To demonstrate the major degraders of petroleum hydrocarbons spilt in actual tropical seas, indigenous bacterial community in seawater at Sentosa (close to a port) and East Coast Park (far from a port) in Singapore was analyzed. Bacterial species was more diverse at Sentosa than at the Park, and the composition was different: γ-Proteobacteria (57.3%) dominated at Sentosa, while they did not at the Park. Specialized hydrocarbonoclastic bacteria (SHCB), which use limited carbon sources with a preference for petroleum hydrocarbons, were found as abundant species at Sentosa, indicating petroleum contamination. On the other hand, SHCB were not the abundant species at the Park. The abundant species of SHCB at Sentosa were Oleibacter marinus and Alcanivorax species (strain 2A75 type), which have previously been indicated by laboratory culturing as important petroleum-aliphatic-hydrocarbon degraders in tropical seas. Together with the fact that SHCB have been identified as major degraders of petroleum hydrocarbons in marine environments, these results demonstrate that the O. marinus and Alcanivorax species (strain 2A75 type) would be major degraders of petroleum aliphatic hydrocarbons spilt in actual tropical seas. PMID:23824553

  14. Specialized Hydrocarbonoclastic Bacteria Prevailing in Seawater around a Port in the Strait of Malacca

    PubMed Central

    Teramoto, Maki; Queck, Shu Yeong; Ohnishi, Kouhei

    2013-01-01

    Major degraders of petroleum hydrocarbons in tropical seas have been indicated only by laboratory culturing and never through observing the bacterial community structure in actual environments. To demonstrate the major degraders of petroleum hydrocarbons spilt in actual tropical seas, indigenous bacterial community in seawater at Sentosa (close to a port) and East Coast Park (far from a port) in Singapore was analyzed. Bacterial species was more diverse at Sentosa than at the Park, and the composition was different: γ-Proteobacteria (57.3%) dominated at Sentosa, while they did not at the Park. Specialized hydrocarbonoclastic bacteria (SHCB), which use limited carbon sources with a preference for petroleum hydrocarbons, were found as abundant species at Sentosa, indicating petroleum contamination. On the other hand, SHCB were not the abundant species at the Park. The abundant species of SHCB at Sentosa were Oleibacter marinus and Alcanivorax species (strain 2A75 type), which have previously been indicated by laboratory culturing as important petroleum-aliphatic-hydrocarbon degraders in tropical seas. Together with the fact that SHCB have been identified as major degraders of petroleum hydrocarbons in marine environments, these results demonstrate that the O. marinus and Alcanivorax species (strain 2A75 type) would be major degraders of petroleum aliphatic hydrocarbons spilt in actual tropical seas. PMID:23824553

  15. Gull contributions of phosphorus and nitrogen to a Cape Cod kettle pond

    USGS Publications Warehouse

    Portnoy, J.W.; Soukup, M.A.

    1990-01-01

    Nutrient excretion rates and the annual contribution of P from the feces of the gulls Larus argentatus and L. marinus (and of N from L. argentatus) to the nutrient budget of Gull Pond (Wellfleet), a soft water seepage lake, have been estimated. Intensive year-round gull counts by species were combined with determinations of defecation rate and the nutrient content of feces to quantitatively assess the P loading rates associated with regular gull use of this coastal pond on a seasonal and annual basis. Total P loading from gulls was estimated to be 52 kg yr?1, with 17 kg from L. argentatus and 35 kg from L. marinus, resulting from about 5.0 ? 106 h yr?1 and 1.7 ? 106 h yr?1 of pond use. This compares with P loading estimates of 67 kg yr?1 from upgradient septic systems, 2 kg yr?1 from precipitation and 3 kg yr?1 from unpolluted ground water. Fifty-six percent of annual gull P loading was associated with migratory activity in late fall. Estimated annual N loading by L. argentatus was 14 kg TKN, 206 g NO3-N, and 1.85 g g NH3-N.

  16. Isolation, cultivation and genomic analysis of magnetosome biomineralization genes of a new genus of South-seeking magnetotactic cocci within the Alphaproteobacteria

    PubMed Central

    Morillo, Viviana; Abreu, Fernanda; Araujo, Ana C.; de Almeida, Luiz G. P.; Enrich-Prast, Alex; Farina, Marcos; de Vasconcelos, Ana T. R.; Bazylinski, Dennis A.; Lins, Ulysses

    2014-01-01

    Although magnetotactic bacteria (MTB) are ubiquitous in aquatic habitats, they are still considered fastidious microorganisms with regard to growth and cultivation with only a relatively low number of axenic cultures available to date. Here, we report the first axenic culture of an MTB isolated in the Southern Hemisphere (Itaipu Lagoon in Rio de Janeiro, Brazil). Cells of this new isolate are coccoid to ovoid in morphology and grow microaerophilically in semi-solid medium containing an oxygen concentration ([O2]) gradient either under chemoorganoheterotrophic or chemolithoautotrophic conditions. Each cell contains a single chain of approximately 10 elongated cuboctahedral magnetite (Fe3O4) magnetosomes. Phylogenetic analysis based on the 16S rRNA gene sequence shows that the coccoid MTB isolated in this study represents a new genus in the Alphaproteobacteria; the name Magnetofaba australis strain IT-1 is proposed. Preliminary genomic data obtained by pyrosequencing shows that M. australis strain IT-1 contains a genomic region with genes involved in biomineralization similar to those found in the most closely related magnetotactic cocci Magnetococcus marinus strain MC-1. However, organization of the magnetosome genes differs from M. marinus. PMID:24616719

  17. Isolation, cultivation and genomic analysis of magnetosome biomineralization genes of a new genus of South-seeking magnetotactic cocci within the Alphaproteobacteria

    SciTech Connect

    Morillo, Viviana; Abreu, Fernanda; Araujo, Ana C; de Almeida, Luiz G; Enrich-Prast, Alex; Farina, Marcos; de Vasconcelos, Ana T; Bazylinski, Dennis A; Lins, Ulysses

    2014-01-01

    Although magnetotactic bacteria (MTB) are ubiquitous in aquatic habitats, they are still considered fastidious microorganisms with regard to growth and cultivation with only a relatively low number of axenic cultures available to date. Here, we report the first axenic culture of an MTB isolated in the Southern Hemisphere (Itaipu Lagoon in Rio de Janeiro, Brazil). Cells of this new isolate are coccoid to ovoid in morphology and grow microaerophilically in semi-solid medium containing an oxygen concentration ([O2]) gradient either under chemoorganoheterotrophic or chemolithoautotrophic conditions. Each cell contains a single chain of approximately 10 elongated cuboctahedral magnetite (Fe3O4) magnetosomes. Phylogenetic analysis based on the 16S rRNA gene sequence shows that the coccoid MTB isolated in this study represents a new genus in the Alphaproteobacteria; the name Magnetofaba australis strain IT-1 is proposed. Preliminary genomic data obtained by pyrosequencing shows that M. australis strain IT-1 contains a genomic region with genes involved in biomineralization similar to those found in the most closely related magnetotactic cocci Magnetococcus marinus strain MC-1. However, organization of the magnetosome genes differs from M. marinus.

  18. Isolation and characterization of the Prochlorococcus carboxysome reveal the presence of the novel shell protein CsoS1D.

    PubMed

    Roberts, Evan W; Cai, Fei; Kerfeld, Cheryl A; Cannon, Gordon C; Heinhorst, Sabine

    2012-02-01

    Cyanobacteria, including members of the genus Prochlorococcus, contain icosahedral protein microcompartments known as carboxysomes that encapsulate multiple copies of the CO(2)-fixing enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase (RubisCO) in a thin protein shell that enhances the catalytic performance of the enzyme in part through the action of a shell-associated carbonic anhydrase. However, the exact mechanism by which compartmentation provides a catalytic advantage to the enzyme is not known. Complicating the study of cyanobacterial carboxysomes has been the inability to obtain homogeneous carboxysome preparations. This study describes the first successful purification and characterization of carboxysomes from the marine cyanobacterium Prochlorococcus marinus MED4. Because the isolated P. marinus MED4 carboxysomes were free from contaminating membrane proteins, their protein complement could be assessed. In addition to the expected shell proteins, the CsoS1D protein that is not encoded by the canonical cso gene clusters of α-cyanobacteria was found to be a low-abundance shell component. This finding and supporting comparative genomic evidence have important implications for carboxysome composition, structure, and function. Our study indicates that carboxysome composition is probably more complex than was previously assumed based on the gene complements of the classical cso gene clusters. PMID:22155772

  19. Parasites infecting the cultured oyster Crassostrea gasar (Adanson, 1757) in Northeast Brazil.

    PubMed

    Queiroga, Fernando Ramos; Vianna, Rogério Tubino; Vieira, Cairé Barreto; Farias, Natanael Dantas; Da Silva, Patricia Mirella

    2015-05-01

    The oyster Crassostrea gasar is a species widely used as food and a source of income for the local population of the estuaries of Northeast Brazil. Perkinsus marinus and Perkinsus olseni are deleterious parasites for oyster farming and were recently detected in Brazil. In this study, a histopathologic survey of the oyster C. gasar cultured in the estuary of the River Mamanguape (Paraíba State) was performed. Adult oysters were collected in December 2011 and March, May, August and October 2012 and processed for histology and Perkinsus sp. identification by molecular analyses. Histopathological analysis revealed the presence of parasitic organisms including viral gametocytic hypertrophy, prokaryote-like colonies, protozoans (Perkinsus sp. and Nematopsis sp.) and metazoans (Tylocephalum sp. and cestodes). Other commensal organisms were also detected (the protozoan Ancistrocoma sp. and the turbellarian Urastoma sp.). The protozoan parasite Perkinsus sp. had the highest overall prevalence among the symbiotic organisms studied (48.9%), followed by Nematopsis sp. (36.3%). The other organisms were only sporadically observed. Only the protozoan Perkinsus sp. caused alterations in the oysters' infected organs. Molecular analyses confirmed the presence of P. marinus, P. olseni and Perkinsus beihaiensis infecting the oyster C. gasar. This is the first report of P. beihaiensis in this oyster species. PMID:25553815

  20. Identifying factors inducing trophozoite differentiation into hypnospores in Perkinsus species.

    PubMed

    Casas, Sandra M; La Peyre, Jerome F

    2013-05-01

    Trophozoites of species of Perkinsus in host tissues readily differentiate into hypnospores when incubated in Ray's fluid thioglycollate medium (RFTM). In contrast, hypnospores have rarely been observed in vivo, and when reported they have been associated with dying hosts. The objective of this study was to determine what altered environmental conditions trigger the differentiation of Perkinsus trophozoites into hypnospores. In the first part of the study, cultured P. chesapeaki trophozoites were exposed to lowered oxygen, acidic pH, increased nutrient levels, heat shock, or osmotic shock conditions, and hypnospore density was measured. Acidic pH, lowered oxygen, or increased nutrient levels significantly increased P. chesapeaki hypnospore formation. In the second part of the study, P. olseni and P. marinus trophozoites were exposed to acidic pH, lowered oxygen, or increased nutrient levels resulting in hypnospore formation in P. olseni but not P. marinus. This study demonstrated that changes in environmental conditions consistent with changes expected in decaying tissues or with RFTM incubation induce trophozoite differentiation. The response of the cultured trophozoites varied between species and between isolates of the same species. PMID:22999495

  1. The search for the missing link: a relic plastid in Perkinsus?

    PubMed

    Fernández Robledo, José A; Caler, Elisabet; Matsuzaki, Motomichi; Keeling, Patrick J; Shanmugam, Dhanasekaran; Roos, David S; Vasta, Gerardo R

    2011-10-01

    Perkinsus marinus (Phylum Perkinsozoa) is a protozoan parasite that has devastated natural and farmed oyster populations in the USA, significantly affecting the shellfish industry and the estuarine environment. The other two genera in the phylum, Parvilucifera and Rastrimonas, are parasites of microeukaryotes. The Perkinsozoa occupies a key position at the base of the dinoflagellate branch, close to its divergence from the Apicomplexa, a clade that includes parasitic protista, many harbouring a relic plastid. Thus, as a taxon that has also evolved toward parasitism, the Perkinsozoa has attracted the attention of biologists interested in the evolution of this organelle, both in its ultrastructure and the conservation, loss or transfer of its genes. A review of the recent literature reveals mounting evidence in support of the presence of a relic plastid in P. marinus, including the presence of multimembrane structures, characteristic metabolic pathways and proteins with a bipartite N-terminal extension. Further, these findings raise intriguing questions regarding the potential functions and unique adaptation of the putative plastid and/or plastid genes in the Perkinsozoa. In this review we analyse the above-mentioned evidence and evaluate the potential future directions and expected benefits of addressing such questions. Given the rapidly expanding molecular/genetic resources and methodological toolbox for Perkinsus spp., these organisms should complement the currently established models for investigating plastid evolution within the Chromalveolata. PMID:21889509

  2. Immune response and mechanical stress susceptibility in diseased oysters, Crassostrea virginica.

    PubMed

    Roberts, Steven B; Sunila, Inke; Wikfors, Gary H

    2012-01-01

    Eastern oysters, Crassostrea virginica, naturally infected with the parasite Perkinsus marinus were subjected to a mechanical stress by centrifugation, and immune parameters, pathological conditions, and gene expression of selected transcripts were compared to uninfected controls. Immune parameters were assessed by flow cytometry, pathology and parasites by histotechnology and fluid thioglycollate assays, and gene expression by quantitative RT-PCR. Irrespective of mechanical stress, an increased number of hemocytes were observed in P. marinus-infected oysters that corresponded to increased expression of genes that have been shown to be involved in inflammation and apoptosis, two processes associated with regulating immune cell populations. Mechanically stressed, diseased oysters showed histological gill abnormalities and aggregations of hemocytes in tissues not seen in stressed, uninfected oysters. Expression of a high-mobility group protein and hemocyte phagocytosis were significantly upregulated upon mechanical stress only in uninfected oysters. The results of this study demonstrate the role of inflammation in the oyster immune response including possible underlying molecular mechanisms. Furthermore, this study highlights the importance of considering mechanical stressors when characterizing oyster immune function. PMID:21853237

  3. Two Perkinsus spp. infect Crassostrea gasar oysters from cultured and wild populations of the Rio São Francisco estuary, Sergipe, northeastern Brazil.

    PubMed

    da Silva, Patricia Mirella; Scardua, Marcos Paiva; Vianna, Rogério Tubino; Mendonça, Raoani Cruz; Vieira, Cairé Barreto; Dungan, Christopher F; Scott, Gail P; Reece, Kimberly S

    2014-06-01

    Brazilian production of bivalve molluscs is small but expanding, especially in the northeastern region where the native oysters Crassostrea rhizophorae and C. gasar are abundant, and tropical weather promotes their rapid growth. Studies on bivalve pathology are scarce in Brazil, with only a few employing techniques for detecting protozoan pathogens listed by the World Organisation for Animal Health (OIE). In 2008, a Perkinsus sp. was reported for the first time in Brazil, infecting C. rhizophorae oysters from a wild population in Ceará state, NE Brazil. Recently P. marinus was detected in the same oyster species in nearby Paraíba state. These findings highlighted the need to expand knowledge on the presence and impacts of Perkinsus spp. on Brazilian oyster populations. The current investigation evaluated Perkinsus sp. infections among wild and cultured C. gasar mangrove oysters from the estuary of the Rio São Francisco, Sergipe state, NE Brazil. Our results show that Perkinsus sp. infections occurred commonly in oysters of both groups, at prevalences that were frequently higher among cultured oysters. Prevalences varied seasonally, with maximum values during summer (January) of 57% and 80% for wild and cultured oysters respectively, and minimum values during winter (July). Results of DNA sequencing, in situ hybridization assays, and phylogenetic analyses showed dual- and single-pathogen infections by P. marinus and/or P. olseni in the tested oysters. PMID:24780219

  4. Salinity effects on viability, metabolic activity and proliferation of three Perkinsus species

    USGS Publications Warehouse

    La, Peyre M.; Casas, S.; La, Peyre J.

    2006-01-01

    Little is known regarding the range of conditions in which many Perkinsus species may proliferate, making it difficult to predict conditions favorable for their expansion, to identify conditions inducing mortality, or to identify instances of potential cross-infectivity among sympatric host species. In this study, the effects of salinity on viability, metabolic activity and proliferation of P. marinus, P. olseni and P. chesapeaki were determined. Specifically, this research examined the effects of 5 salinities (7, 11, 15, 25, 35???), (1) without acclimation, on the viability and metabolic activity of 2 isolates of each Perkinsus species, and (2) with acclimation, on the viability, metabolic activity, size and number of 1 isolate of each species. P. chesapeaki showed the widest range of salinity tolerance of the 3 species, with high viability and cell proliferation at all salinities tested. Although P. chesapeaki originated from low salinity areas (i.e. <15???), several measures (i.e. cell number and metabolic activity) indicated that higher salinities (15, 25???) were more favorable for its growth. P. olseni, originating from high salinity areas, had better viability and proliferation at the higher salinities (15, 25, 35???). Distinct differences in acute salinity response of the 2 P. olseni isolates at lower salinities (7, 11???), however, suggest the need for a more expansive comparison of isolates to better define the lower salinity tolerance. Lastly, P. marinus was more tolerant of the lower salinities (7 and 11???) than P. olseni, but exhibited reduced viability at 7???, even after acclimation. ?? Inter-Research 2006.

  5. Use of molecular markers for species identification of Korean Perkinsus sp. isolated from Manila clams Ruditapes philippinarum.

    PubMed

    Park, Kyung-Il; Park, Joong-Ki; Lee, Jehee; Choi, Kwang-Sik

    2005-09-23

    Perkinsus is the pathogen responsible for mass mortality of the Manila clam Ruditapes philippinarum. Perkinsus sp. isolated from Manila clams collected in Korean waters was assayed by polymerase chain reaction (PCR) to determine its phylogenetic affinity with other congeneric species. Regions of rRNA of Perkinsus sp. isolated from clam haemolymph were cloned and sequenced. Sequences of a non-transcribed spacer (NTS), internal transcribed spacers (ITS 1, 2) and 5.8S rRNA genes were compared to those available from other Perkinsus species. The NTS sequence of Korean Perkinsus was approximately 99.9 to 100% similar to that of P. atlanticus and 98.06 to 98.15% and 73.05 to 73.14% similar to those of P. olseni and P. marinus, respectively. The ITS 1, 5.8S rRNA and ITS 2 sequences of Korean Perkinsus showed 100% similarity to P. atlanticus and Perkinsus sp. reported from Japan. The ITS-5.8S rRNA sequences of Korean Perkinsus were 99.86 and 93.73% similar to those of P. olseni and P. marinus, respectively. The sporulation pattern and morphology of the Korean Perkinsus were very similar to those of P. atlanticus. Our data suggest that the Perkinsus sp. isolated from clams in Korean waters is P. atlanticus, which is currently synonymous with P. olseni reported from Australia. By considering that P. olseni has taxonomic priority, Korean Perkinsus sp. is accepted as P. olseni (atlanticus). PMID:16261941

  6. Perkinsus olseni detected in Vietnamese aquacultured reef clams Tridacna crocea imported to the USA, following a mortality event.

    PubMed

    Sheppard, Barbara J; Phillips, Ayanna Carla

    2008-05-01

    Morbidity and mortality were observed in a group of 30 reef clams Tridacna crocea that were imported to Florida, USA, from a Vietnamese culture facility and held in research facility aquaria. Clinical signs included an incompletely extended mantle, slow mantle responses to stimuli, and sloughing of byssal tissue beginning 2 to 5 d prior to death. Necropsy findings included emaciation, visceral mass edema, and rare multifocal 1 mm off-white to light-tan gill nodules. Histopathology revealed marked inflammation and necrosis within the visceral mass and gills, with interstitial edema and atrophy of glandular, gonadal, and muscular tissues. Inflamed tissues contained large numbers of 10 to 15 microm extracellular round organisms consistent with Perkinsus sp. trophozoites. The organisms often formed clusters of 1 to 4 cells and were surrounded by a 1 to 3 microm rim of eosinophilic material variably forming a radiating corona pattern and by 3 to 4 host hemocytes with dense round nuclei. Polymerase chain reaction assays indicated the presence of Perkinsus sp. DNA in these animals, and species-specific assays indicated the presence of P. olseni, and possibly other Perkinsus spp., but not P. marinus. Identification of Perkinsus spp. other than P. marinus in T. crocea imported from Vietnam confirms that importation of untested and unquarantined ornamental reef clams has possibly allowed incursion of P. olseni into the USA. PMID:18589999

  7. An investigation into intersex amphipods and a possible association with aquaculture.

    PubMed

    Ford, Alex T; Read, Paul A; Jones, Tim L; Michino, Fumiko; Pang, Yvonne; Fernandes, Teresa F

    2007-10-01

    The amphipod, Echinogammarus marinus, is common in sheltered coastal inlets, such as estuaries and sea lochs, in Scotland and exhibits increased levels of intersex in some contaminated areas. Sea lochs are commonly the location for coastal aquaculture development, and some chemicals used in fish-farming are specifically designed to target the crustacean nervous system. Therefore it was hypothesised that these chemicals may also affect neuro-endocrine pathways, causing morphological and reproductive abnormalities in non-target Crustacea. Based upon this hypothesis, Echinogammarus marinus amphipods from two different Scottish sea lochs containing salmon farms were investigated. Morphology, intersexuality, and the incidence of microsporidian parasites were recorded at sites close and at distance from fish-farms. Results suggest a higher incidence of intersexuality at sites within sea lochs, comparable to that observed in industrially contaminated sites elsewhere in Scotland. The data suggest that fish farming activity may influence the observed distributions of intersexuality within lochs. Intersex specimens were more likely to be infected by microsporidian parasites than non-intersex specimens. Normal females were found more likely to be infected by microsporidian parasites at sites associated with high intersexuality, suggesting the parasite as the probable feminiser. The cause(s) for the observed patterns of intersexuality are unclear, although suggestions relating to discharges from fish farms are discussed. PMID:17499352

  8. Microarray-based analysis of survival of soil microbial community during ozonation

    SciTech Connect

    Wang, Jian; Van Nostrand, Joy D.; He, Zhili; Wu, Liyou; Deng, Ye; Zhang, Xu; Zhou, Jizhong; Li, Guanghe

    2010-05-17

    A 15 h ozonation was performed on bioremediated soil to remove recalcitrant residual oil. To monitor the survival of indigenous microorganisms in the soil during in-situ chemical oxidation(ISCO) culturing and a functional genearray, GeoChip, was used to examine the functional genes and structure of the microbial community during ozonation (0h, 2h, 4h, 6h, 10hand15h). Breakthrough ozonation decreased the population of cultivable heterotrophic bacteria by about 3 orders of magnitude. The total functional gene abundance and diversity decreased during ozonation, as the number of functional genes was reduced by 48percent after 15 h. However, functional genes were evenly distributed during ozonation as judged by the Shannon-Weaver Evenness index. A sharp decrease in gene number was observed in the first 6 h of ozonation followed by a slower decrease in the next 9 h, which was consistent with microbial populations measured by a culture based method. Functional genes involved in carbon, nitrogen, phosphors and sulfur cycling, metal resistance and organic remediation were detected in all samples. Though the pattern of gene categories detected was similar for all time points, hierarchica lcluster of all functional genes and major functional categories all showed a time-serial pattern. Bacteria, archaea and fungi decreased by 96.1percent, 95.1percent and 91.3percent, respectively, after 15 h ozonation. Delta proteobacteria, which were reduced by 94.3percent, showed the highest resistance to ozonation while Actinobacteria, reduced by 96.3percent, showed the lowest resistance. Microorganisms similar to Rhodothermus, Obesumbacterium, Staphylothermus, Gluconobacter, and Enterococcus were dominant at all time points. Functional genes related to petroleum degradation decreased 1~;;2 orders of magnitude. Most of the key functional genes were still detected after ozonation, allowing a rapid recovery of the microbial community after ozonation. While ozone had a large impact on the

  9. Sterilizing effects of cobalt-60 and cesium-137 radiation on male sea lampreys

    USGS Publications Warehouse

    Hanson, L.H.

    1990-01-01

    Male spawning-run sea lampreys Petromyzon marinus were exposed to various doses of cobalt-60 or cesium-137 radiation in an attempt to sterilize them for use in a program for controlling sea lampreys through the release of sterile males. Males captured and irradiated during the early part of the upstream migration were not effectively sterilized at the doses tested. After irradiation, the sea lampreys were more susceptible to fungal infections by Saprolegnia sp., and many died without attempting to spawn. Males captured and irradiated during the middle and late parts of the spawning migration were effectively sterilized at a dose of 2,000 rads. However, some radiation-induced mortality was observed in males captured and irradiated during the middle part of the spawning migration. Radiation is not as effective as the chemosterilant bisazir for sterilizing male sea lampreys.

  10. Environmental fate and effects of the lampricide TFM: A review

    USGS Publications Warehouse

    Hubert, T.D.

    2003-01-01

    Use of 3-trifluoromethyl-4-nitrophenol (TFM) is limited geographically to the Great Lakes basin where it is the principal agent used in control of the sea lamprey (Petromyzon marinus). It is clear from available data that TFM has effects on the environment, but the effects reported are transient. Individual organisms and aquatic communities return to pretreatment conditions after lampricide treatments have concluded. TFM is not persistent, is detoxified, and presents minimal long-term toxicological risk. TFM is relatively nontoxic to mammals. Treatment levels do not pose a threat to wildlife. However, TFM is an estrogen agonist and additional testing to define the nature and magnitude of this effect will likely be required. Because stream treatments are done on 3 to 5 year cycles, and exposures are limited to approximately 12 h, minimal risk to aquatic organisms is expected.

  11. Environmental fate and effects of the lampricide TFM: a review

    USGS Publications Warehouse

    Hubert, T.D.

    2003-01-01

    Use of 3-trifluoromethyl-4-nitrophenol (TFM) is limited geographically to the Great Lakes basin where it is the principal agent used in control of the sea lamprey (Petromyzon marinus). It is clear from available data that TFM has effects on the environment, but the effects reported are transient. Individual organisms and aquatic communities return to pretreatment conditions after lampricide treatments have concluded. TFM is not persistent, is detoxified, and presents minimal long-term toxicological risk. TFM is relatively nontoxic to mammals. Treatment levels do not pose a threat to wildlife. However, TFM is an estrogen agonist and additional testing to define the nature and magnitude of this effect will likely be required. Because stream treatments are done on 3 to 5 year cycles, and exposures are limited to approximately 12 h, minimal risk to aquatic organisms is expected.

  12. Microbial Specificity of Metallic Surfaces Exposed to Ambient Seawater

    PubMed Central

    Zaidi, B. R.; Bard, R. F.; Tosteson, T. R.

    1984-01-01

    High-molecular-weight materials associated with the extracellular matrix and film found on titanium and aluminum surfaces after exposure to flowing coastal seawater were isolated. This material was purified by hydroxylapatite chromatography and subsequently employed to produce antibodies in the toad, Bufo marinus. The antibodies were immobilized on a solid support and employed to isolate adhesion-enhancing, high-molecular-weight materials from the laboratory culture media of bacterial strains recovered from the respective metallic surfaces during the course of their exposure to seawater. The adhesion-enhancing materials produced by the surface-associated bacterial strains were immunologically related to the extracellular biofouling matrix material found on the surfaces from which these bacteria were isolated. The surface selectivity of these bacterial strains appeared to be based on the specificity of the interaction between adhesion-enhancing macromolecules produced by these bacteria and the surfaces in question. PMID:16346622

  13. The fluorescent protein palette: tools for cellular imaging†

    PubMed Central

    Davidson, Michael W.

    2010-01-01

    This critical review provides an overview of the continually expanding family of fluorescent proteins (FPs) that have become essential tools for studies of cell biology and physiology. Here, we describe the characteristics of the genetically encoded fluorescent markers that now span the visible spectrum from deep blue to deep red. We identify some of the novel FPs that have unusual characteristics that make them useful reporters of the dynamic behaviors of proteins inside cells, and describe how many different optical methods can be combined with the FPs to provide quantitative measurements in living systems. “If wood is rubbed with the Pulmo marinus, it will have all the appearance of being on fire; so much so, indeed, that a walking-stick, thus treated, will light the way like a torch” (translation of Pliny the Elder from John Bostock, 1855). PMID:19771335

  14. Visualization of Iron-Binding Micelles in Acidic Recombinant Biomineralization Protein, MamC

    SciTech Connect

    Kashyap, Sanjay; Woehl, Taylor; Valverde-Tercedor, Carmen; Sanchez-Quesada, Miguel; Lopez, Concepcion Jimenez; Prozorov, Tanya

    2014-03-07

    Biological macromolecules are utilized in low-temperature synthetic methods to exert precise control over nanoparticle nucleation and placement. They enable low-temperature formation of a variety of functional nanostructured materials with properties often not achieved via conventional synthetic techniques. Here we report on the in situ visualization of a novel acidic bacterial recombinant protein, MamC, commonly present in the magnetosome membrane of several magnetotactic bacteria, including Magnetococcus marinus, strain MC-1. Our findings provide an insight into the self-assembly of MamC and point to formation of the extended protein surface, which is assumed to play an important role in the formation of biotemplated inorganic nanoparticles. The self-organization of MamC is compared to the behavior of another acidic recombinant iron-binding protein, Mms6.

  15. An aquarium experiment on the American eel as a predator on larval lampreys

    USGS Publications Warehouse

    Perlmutter, Alfred

    1951-01-01

    The parasitic sea lamprey, Petromyzon marinus, has in recent years spread throughout Lakes Huron and Michigan and is now firmly established in these waters (Applegate, 1949, Mich. Cons., 18 (4): 13-15). Coincident with their spread, the abundance of lake trout, Salvelinus namaycush, has declined in both lakes (Hile, 1949, Trans. Amer. Fish. Soc., 76 (1946): 121-147) and the lake trout as well as other species of fishes are showing an increase in scarring from lamprey attacks. For Lake Michigan the analysis of fishermen's questionnaires gave an increase in percentage by weight of lamprey-scarred lake trout from 31 percent in 1947 to 41 percent in 1948. The sea lamprey is now spreading through Lake Superior, the last of the Great Lakes containing a large population of lake trout.

  16. Density-independent survival of wild lake trout in the Apostle Islands area of Lake Superior

    USGS Publications Warehouse

    Bronte, Charles R.; Schram, Stephen T.; Selgeby, James H.; Swanson, Bruce L.

    1995-01-01

    The lake trout (Salvelinus namaycush) stock at Gull Island Shoal in western Lake Superior was one of only a few stocks of lean lake trout in the Great Lakes that survived overfishing and predation by the sea lamprey (Petromyzon marinus). Since the mid 1960s, the abundance of wild recruits measured at age 0 and the number of age-7 to -11 wild fish recruited to the fishable stock have increased. We used the Varley-Gradwell method to test for density-dependent survival between these life stages. Survival from age-0 to ages 7–11 was not affected by increasing density, which suggests that further increases in recruitment and stock size are still possible. We suggest that testing for the existence of density-dependent survival can be used to indicate when lake trout populations are rehabilitated.

  17. Microbial specificity of metallic surfaces exposed to ambient seawater

    SciTech Connect

    Zaidi, B.R.; Bard, R.F.; Tosteson, T.R.

    1984-09-01

    High-molecular-weight materials associated with the extracellular matrix and film found on titanium and aluminum surfaces after exposure to flowing coastal seawater were isolated. This material was purified by hydroxylapatite chromatography and subsequently employed to produce antibodies in the toad, Bufo marinus. The antibodies were immobilized on a solid support and employed to isolate adhesion-enhancing, high-molecular-weight materials from the laboratory culture media of bacterial strains recovered from the respective metallic surfaces during the course of their exposure to seawater. The adhesion-enhancing materials produced by the surface-associated bacterial strains were immunologically related to the extracellular biofouling matrix material found on the surfaces from which these bacteria were isolated. The surface selectivity of these bacterial strains appeared to be based on the specificity of the interaction between adhesion-enhancing macromolecules produced by these bacteria and the surfaces in question. 30 references, 6 tables.

  18. Crystal structure and functional characterization of a light-driven chloride pump having an NTQ motif.

    PubMed

    Kim, Kuglae; Kwon, Soon-Kyeong; Jun, Sung-Hoon; Cha, Jeong Seok; Kim, Hoyoung; Lee, Weontae; Kim, Jihyun F; Cho, Hyun-Soo

    2016-01-01

    A novel light-driven chloride-pumping rhodopsin (ClR) containing an 'NTQ motif' in its putative ion conduction pathway has been discovered and functionally characterized in a genomic analysis study of a marine bacterium. Here we report the crystal structure of ClR from the flavobacterium Nonlabens marinus S1-08(T) determined under two conditions at 2.0 and 1.56 Å resolutions. The structures reveal two chloride-binding sites, one around the protonated Schiff base and the other on a cytoplasmic loop. We identify a '3 omega motif' formed by three non-consecutive aromatic amino acids that is correlated with the B-C loop orientation. Detailed ClR structural analyses with functional studies in E. coli reveal the chloride ion transduction pathway. Our results help understand the molecular mechanism and physiological role of ClR and provide a structural basis for optogenetic applications. PMID:27554809

  19. Acute toxic effects of two lampricides on twenty-one freshwater invertebrates

    USGS Publications Warehouse

    Rye, Robert P., Jr.; King, Everett Louis, Jr.

    1976-01-01

    We conducted laboratory static bioassays to determine acute toxicity of two lampricides -- a 70% 2-aminoethanol salt of 5,2'dichloro-4'-nitrosalicylanilide (Bayer 73) and a mixture containing 98% 3-trifluoromethyl-4-nitrophenol (TFM) and 2% Bayer 73 (TFM-2B) -- to 21 freshwater invertebrates. LC50 values were determined for 24-h exposure periods at 12.8 C. Organisms relatively sensitive to Bayer 73 were a turbellarian (Dugesia tigrina), aquatic earthworms (Tubifex tubifex and Lumbriculus inconstans), snails (Physa sp.) and (Pleurocera sp.), a clam (Eliptio dilatatus), blackflies (Simulium sp.), leeches (Erpobdellidae), and a daphnid (Daphnia pulex). The invertebrates most sensitive to TFM-2B were turbellarians, aquatic earthworms (Tubifex), snails (Physa), blackflies, leeches, and burrowing mayflies (Hexagenia sp.). Bayer 73 was generally much more toxic to the test organisms than TFM-2B. At lampricidal concentrations, TFM-2B was more highly selective than Bayer 73 against larval sea lampreys (Petromyzon marinus).

  20. Acute Toxicity of the Lampricides TFM and Niclosamide to Three Species of Unionid Mussels

    USGS Publications Warehouse

    Boogaard, Michael A.

    2006-01-01

    The sea lamprey (Petromyzon marinus), a jawless parasitic eel-like fish native to the Atlantic Ocean (fig. 1), was accidentally introduced into the Great Lakes in the early 20th century through the construction of shipping canals. A member of the Petromyzonidae family, the primitive parasite has been identified as a major cause of the collapse of the Great Lakes fishery in the 1940s and 1950s. The lampricides 3-trifluoromethyl-4-nitrophenol (TFM) and 2'5-dichloro-4'-nitrosalicylanilide (niclosamide) have been used to control larval sea lampreys in tributaries of the Great Lakes since the early 1960s. The lampricide TFM is the main compound used to keep sea lamprey populations in check while niclosamide is used primarily in combination with TFM as a cost-saving measure. The addition of niclosamide at a ratio of 1% to TFM will reduce the amount of TFM required for effective treatment by about 40%.

  1. Experimental hybridization among five species of lampreys from the Great Lakes

    USGS Publications Warehouse

    Piavis, George W.; Howell, John H.; Smith, Allen J.

    1970-01-01

    Experimental hybridization among five species of lampreys of the Upper Great Lakes routinely produced embryos through stage 8, and four crosses produced embryos to the larval stage. Three critical periods in the embryogenesis of hybrid lampreys were between stages 8 and 9, among stages 10, 11, and 12, and at stage 15. Embryonic development in hybrid lamprey embryos is basically identical to that of controls and is identical to that of the sea lamprey (Petromyzon marinus). Synchrony of development was observed among stages of viable hybrids and their controls but lethal hybrids generally did not maintain such synchrony. The derivative species concept has been confirmed experimentally. Questions have been raised concerning some evidence cited in behalf of the appropriateness of the concept that nonparasitic lampreys are the derived species.

  2. A portable trap with electric lead catches up to 75% of an invasive fish species

    USGS Publications Warehouse

    Johnson, Nicholas; Miehls, Scott M.; O'Connor, Lisa M; Bravener, Gale; Barber, Jessica; Thompson, Henry T.; Tix, John A.; Bruning, Tyler

    2016-01-01

    A novel system combining a trap and pulsed direct current electricity was able to catch up to 75% of tagged invasive sea lamprey Petromyzon marinus in free-flowing streams. Non-target mortality was rare and impacts to non-target migration were minimal; likely because pulsed direct current only needed to be activated at night (7 hours of each day). The system was completely portable and the annual cost of the trapping system was low ($4,800 U.S. dollars). Use of the technology is poised to substantially advance integrated control of sea lamprey, which threaten a fishery valued at 7 billion U.S. dollars annually, and help restore sea lamprey populations in Europe where they are native, but imperiled. The system may be broadly applicable to controlling invasive fishes and restoring valued fishes worldwide, thus having far reaching effects on ecosystems and societies.

  3. Effect of size on lake trout survival after a single sea lamprey attack

    USGS Publications Warehouse

    Swink, William D.

    1990-01-01

    When lake trout Salvelinus namaycush were subjected to a single attack by a sea lamprey Petromyzon marinus in laboratory tests in 1986, percentage mortality was significantly higher in small fish (64%; 469-557 mm; N = 67) than in medium (44%; 559-643 mm; N = 45) or large fish (43%; 660-799 mm; N = 47). Additional studies conducted in 1987 with 55 medium (559-650 mm) and 52 large (660-825 mm) lake trout confirmed that there was no difference in mortality between the two larger size-groups. Mortality declined in lake trout over 559 mm, but was still greater than 43%. This level of mortality and the sea lampreys' apparently active selection of larger fish indicated that, contrary to previously published opinions, large size in lake trout (up to ∼800 mm in length) might not allow better survival from single sea lamprey attacks.

  4. A portable trap with electric lead catches up to 75% of an invasive fish species

    NASA Astrophysics Data System (ADS)

    Johnson, Nicholas S.; Miehls, Scott; O’Connor, Lisa M.; Bravener, Gale; Barber, Jessica; Thompson, Henry; Tix, John A.; Bruning, Tyler

    2016-06-01

    A novel system combining a trap and pulsed direct current electricity was able to catch up to 75% of tagged invasive sea lamprey Petromyzon marinus in free-flowing streams. Non-target mortality was rare and impacts to non-target migration were minimal; likely because pulsed direct current only needed to be activated at night (7 hours of each day). The system was completely portable and the annual cost of the trapping system was low ($4,800 U.S. dollars). Use of the technology is poised to substantially advance integrated control of sea lamprey, which threaten a fishery valued at 7 billion U.S. dollars annually, and help restore sea lamprey populations in Europe where they are native, but imperiled. The system may be broadly applicable to controlling invasive fishes and restoring valued fishes worldwide, thus having far reaching effects on ecosystems and societies.

  5. The ancestral role of nodal signalling in breaking L/R symmetry in the vertebrate forebrain.

    PubMed

    Lagadec, Ronan; Laguerre, Laurent; Menuet, Arnaud; Amara, Anis; Rocancourt, Claire; Péricard, Pierre; Godard, Benoît G; Rodicio, Maria Celina; Rodriguez-Moldes, Isabel; Mayeur, Hélène; Rougemont, Quentin; Mazan, Sylvie; Boutet, Agnès

    2015-01-01

    Left-right asymmetries in the epithalamic region of the brain are widespread across vertebrates, but their magnitude and laterality varies among species. Whether these differences reflect independent origins of forebrain asymmetries or taxa-specific diversifications of an ancient vertebrate feature remains unknown. Here we show that the catshark Scyliorhinus canicula and the lampreys Petromyzon marinus and Lampetra planeri exhibit conserved molecular asymmetries between the left and right developing habenulae. Long-term pharmacological treatments in these species show that nodal signalling is essential to their generation, rather than their directionality as in teleosts. Moreover, in contrast to zebrafish, habenular left-right differences are observed in the absence of overt asymmetry of the adjacent pineal field. These data support an ancient origin of epithalamic asymmetry, and suggest that a nodal-dependent asymmetry programme operated in the forebrain of ancestral vertebrates before evolving into a variable trait in bony fish. PMID:25819227

  6. Growth, age at metamorphosis, and sex ratio of northern brook lamprey in a tributary of southern Lake Superior

    USGS Publications Warehouse

    Purvis, Harold A.

    1970-01-01

    Growth was studied of five year classes of the northern brook lamprey, Ichthyomyzon fossor, collected from the Sturgeon River during intervals between treatment of the stream with a lampricide. Growth varied considerably among year classes. Larvae of the 1963 year class were slightly longer at age II and 30% longer at age III than the III-group larvae of the 1960 year class. About 6% of 558 III-group lampreys of the 1963 year class had metamorphosed by 17 August 1966. Although the sex ratio of larvae was about 1:1, 97% of the metamorphosed lampreys were males. The distribution of pigmentation on the caudal fin and upper lip in ammocoetes less than 40 mm long permitted accurate and rapid separation of northern brook lampreys from the sea lamprey, Petromyzon marinus.

  7. A portable trap with electric lead catches up to 75% of an invasive fish species.

    PubMed

    Johnson, Nicholas S; Miehls, Scott; O'Connor, Lisa M; Bravener, Gale; Barber, Jessica; Thompson, Henry; Tix, John A; Bruning, Tyler

    2016-01-01

    A novel system combining a trap and pulsed direct current electricity was able to catch up to 75% of tagged invasive sea lamprey Petromyzon marinus in free-flowing streams. Non-target mortality was rare and impacts to non-target migration were minimal; likely because pulsed direct current only needed to be activated at night (7 hours of each day). The system was completely portable and the annual cost of the trapping system was low ($4,800 U.S. dollars). Use of the technology is poised to substantially advance integrated control of sea lamprey, which threaten a fishery valued at 7 billion U.S. dollars annually, and help restore sea lamprey populations in Europe where they are native, but imperiled. The system may be broadly applicable to controlling invasive fishes and restoring valued fishes worldwide, thus having far reaching effects on ecosystems and societies. PMID:27341485

  8. Electrophoretic approach to the biochemical systematics of gammarids

    NASA Astrophysics Data System (ADS)

    Bulnheim, H.-P.; Scholl, A.

    1981-12-01

    By utilizing the techniques for electrophoretic separation of proteins by vertical starch gels, the biochemical systematics of 10 Gammaridae species obtained from marine, brackish and freshwater habitats was studied. They included Chaetogammarus marinus, Gammarus zaddachi, G. salinus, G. oceanicus, G. tigrinus, G. chevreuxi, G. locusta, G. duebeni duebeni, G. d. celticus, G. pulex pulex, and G. fossarum. For comparison of electrophoretic mobilities selected enzymes (phosphoglucose isomerase, glutamate oxalacetate transaminase, arginine phosphokinase, hexokinase, leucine amino peptidase, mannose 6-phosphate isomerase) were assayed. They were used as diagnostic characters in terms of electrophoretic identities or diversities of most frequent alleles at polymorphic gene loci. These criteria could be applied to estimate intrageneric enzymic variation and degrees of genetic relatedness between the crustacean amphipod species under consideration, thereby complementing traditional morphological classification.

  9. A portable trap with electric lead catches up to 75% of an invasive fish species

    PubMed Central

    Johnson, Nicholas S.; Miehls, Scott; O’Connor, Lisa M.; Bravener, Gale; Barber, Jessica; Thompson, Henry; Tix, John A.; Bruning, Tyler

    2016-01-01

    A novel system combining a trap and pulsed direct current electricity was able to catch up to 75% of tagged invasive sea lamprey Petromyzon marinus in free-flowing streams. Non-target mortality was rare and impacts to non-target migration were minimal; likely because pulsed direct current only needed to be activated at night (7 hours of each day). The system was completely portable and the annual cost of the trapping system was low ($4,800 U.S. dollars). Use of the technology is poised to substantially advance integrated control of sea lamprey, which threaten a fishery valued at 7 billion U.S. dollars annually, and help restore sea lamprey populations in Europe where they are native, but imperiled. The system may be broadly applicable to controlling invasive fishes and restoring valued fishes worldwide, thus having far reaching effects on ecosystems and societies. PMID:27341485

  10. Effects of egg oiling on larid productivity and population dynamics

    USGS Publications Warehouse

    Lewis, S.J.; Malecki, R.A.

    1984-01-01

    In this study, oil was applied to naturally incubated great black-backed gull (Larus marinus) and herring gull (L. argentatus) eggs, and its effects on reproductive success were assessed. Embryo survival was inversely proportional to the quantity of petroleum applied to eggshell surfaces. Dose responses, however, were dependent on embryonic age at the time of treatment. Eggs of either species, treated with 10-20 mu l of No. 2 fuel oil 4-8 days after laying, experienced significant reductions in hatching success. Embryos oiled past the midpoint of the 28-day incubation period were insensitive to as much as 100 mu l of petroleum. Fuel oil weathered outdoors for several weeks was as toxic as fresh oil to larid embryos. Only under severe conditions (e.g., large doses of petroleum contaminating young embryos) could egg oiling have a significant impact upon populations of the herring gull and species with similar life-history characteristics.

  11. Occurrence of Vibrio vulnificus and toxigenic Vibrio parahaemolyticus on sea catfishes from Galveston Bay, Texas.

    PubMed

    Baumeister, Leslie; Hochman, Mona E; Schwarz, John R; Brinkmeyer, Robin

    2014-10-01

    Dorsal and pectoral fin spines from two species of sea catfishes (Bagre marinus and Ariopsis felis) landed at 54 sites in Galveston Bay, Texas, and its sub-bays from June to October 2005 were screened with traditional cultivation-based assays and quantitative PCR assays for Vibrio vulnificus and Vibrio parahaemolyticus. V. vulnificus was present on 51.2% of fish (n = 247), with an average of 403 ± 337 SD cells g(-1). V. parahaemolyticus was present on 94.2% (n = 247); 12.8% tested positive for the virulence-conferring tdh gene, having an average 2,039 ± 2,171 SD cells g(-1). The increasing trend in seafood consumption of "trash fishes" from lower trophic levels, such as sea catfishes, warrants evaluation of their life histories for association with pathogens of concern for human consumption. PMID:25285498

  12. Perkinsus chesapeaki in stout razor clams Tagelus plebeius from Delaware Bay.

    PubMed

    Bushek, David; Landau, Brenda; Scarpa, Emily

    2008-01-24

    Perkinsus chesapeaki is reported from stout razor clams Tagelus plebeius in Delaware Bay, extending the known range of P. chesapeaki north of Chesapeake Bay. P. marinus, which causes dermo disease, is prevalent in cultured and wild oysters at this site, but was not detected in T. plebeius. Evidence for the presence of disseminated neoplasia, also reported from Chesapeake Bay, was equivocal. Although P. chesapeaki infections were associated with mortality events, light infection intensities and a general lack of histopathological evidence of disease limit inferences about a causal relationship. A comparison of Ray's fluid thioglycollate medium (RFTM)-based and PCR-based detection assays highlight differences in detection capabilities related to the quantity and type of tissue processed rather than assay sensitivity per se, a point that should be considered when surveying populations for disease prevalence. Investigators are further cautioned to use care when applying and interpreting diagnostic assays when used with novel species. PMID:18380223

  13. Visualization of Iron-Binding Micelles in Acidic Recombinant Biomineralization Protein, MamC

    DOE PAGESBeta

    Kashyap, Sanjay; Woehl, Taylor; Valverde-Tercedor, Carmen; Sánchez-Quesada, Miguel; Jiménez López, Concepción; Prozorov, Tanya

    2014-01-01

    Biological macromolecules are utilized in low-temperature synthetic methods to exert precise control over nanoparticle nucleation and placement. They enable low-temperature formation of a variety of functional nanostructured materials with properties often not achieved via conventional synthetic techniques. Here we report on the in situ visualization of a novel acidic bacterial recombinant protein, MamC, commonly present in the magnetosome membrane of several magnetotactic bacteria, including Magnetococcus marinus , strain MC-1. Our findings provide an insight into the self-assembly of MamC and point to formation of the extended protein surface, which is assumed to play an important role in the formationmore » of biotemplated inorganic nanoparticles. The self-organization of MamC is compared to the behavior of another acidic recombinant iron-binding protein, Mms6.« less

  14. Miniaturized Bioaffinity Assessment Coupled to Mass Spectrometry for Guided Purification of Bioactives from Toad and Cone Snail

    PubMed Central

    Heus, Ferry; Otvos, Reka A.; Aspers, Ruud L. E. G.; van Elk, Rene; Halff, Jenny I.; Ehlers, Andreas W.; Dutertre, Sébastien; Lewis, Richard J.; Wijmenga, Sybren; Smit, August B.; Niessen, Wilfried M. A.; Kool, Jeroen

    2014-01-01

    A nano-flow high-resolution screening platform, featuring a parallel chip-based microfluidic bioassay and mass spectrometry coupled to nano-liquid chromatography, was applied to screen animal venoms for nicotinic acetylcholine receptor like (nAChR) affinity by using the acetylcholine binding protein, a mimic of the nAChR. The potential of this microfluidic platform is demonstrated by profiling the Conus textile venom proteome, consisting of over 1,000 peptides. Within one analysis (<90 min, 500 ng venom injected), ligands are detected and identified. To show applicability for non-peptides, small molecular ligands such as steroidal ligands were identified in skin secretions from two toad species (Bufo alvarius and Bufo marinus). Bioactives from the toad samples were subsequently isolated by MS-guided fractionation. The fractions analyzed by NMR and a radioligand binding assay with α7-nAChR confirmed the identity and bioactivity of several new ligands. PMID:24833338

  15. Squalamine as a broad-spectrum systemic antiviral agent with therapeutic potential

    PubMed Central

    Zasloff, Michael; Adams, A. Paige; Beckerman, Bernard; Campbell, Ann; Han, Ziying; Luijten, Erik; Meza, Isaura; Julander, Justin; Mishra, Abhijit; Qu, Wei; Taylor, John M.; Weaver, Scott C.; Wong, Gerard C. L.

    2011-01-01

    Antiviral compounds that increase the resistance of host tissues represent an attractive class of therapeutic. Here, we show that squalamine, a compound previously isolated from the tissues of the dogfish shark (Squalus acanthias) and the sea lamprey (Petromyzon marinus), exhibits broad-spectrum antiviral activity against human pathogens, which were studied in vitro as well as in vivo. Both RNA- and DNA-enveloped viruses are shown to be susceptible. The proposed mechanism involves the capacity of squalamine, a cationic amphipathic sterol, to neutralize the negative electrostatic surface charge of intracellular membranes in a way that renders the cell less effective in supporting viral replication. Because squalamine can be readily synthesized and has a known safety profile in man, we believe its potential as a broad-spectrum human antiviral agent should be explored. PMID:21930925

  16. Squalamine as a broad-spectrum systemic antiviral agent with therapeutic potential.

    PubMed

    Zasloff, Michael; Adams, A Paige; Beckerman, Bernard; Campbell, Ann; Han, Ziying; Luijten, Erik; Meza, Isaura; Julander, Justin; Mishra, Abhijit; Qu, Wei; Taylor, John M; Weaver, Scott C; Wong, Gerard C L

    2011-09-20

    Antiviral compounds that increase the resistance of host tissues represent an attractive class of therapeutic. Here, we show that squalamine, a compound previously isolated from the tissues of the dogfish shark (Squalus acanthias) and the sea lamprey (Petromyzon marinus), exhibits broad-spectrum antiviral activity against human pathogens, which were studied in vitro as well as in vivo. Both RNA- and DNA-enveloped viruses are shown to be susceptible. The proposed mechanism involves the capacity of squalamine, a cationic amphipathic sterol, to neutralize the negative electrostatic surface charge of intracellular membranes in a way that renders the cell less effective in supporting viral replication. Because squalamine can be readily synthesized and has a known safety profile in man, we believe its potential as a broad-spectrum human antiviral agent should be explored. PMID:21930925

  17. Real-time analysis of gut flora in Entamoeba histolytica infected patients of Northern India

    PubMed Central

    2012-01-01

    Background Amebic dysentery is caused by the protozoan parasite Entamoeba histolytica and the ingestion of quadrinucleate cyst of E. histolytica from fecally contaminated food or water initiates infection. Excystation occurs in the lumen of small intestine, where motile and potentially invasive trophozoites germinate from cysts. The ability of trophozoites to interact and digest gut bacteria is apparently important for multiplication of the parasite and its pathogenicity; however the contribution of resident bacterial flora is not well understood. We quantified the population of Bacteroides, Bifidobacterium, Ruminococcus, Lactobacillus, Clostridium leptum subgroup, Clostridium coccoides subgroup, Eubacterium, Campylobacter, Methanobrevibacter smithii and Sulphur reducing bacteria using genus specific primers in healthy (N = 22) vs amebic patients (E. histolytica positive, N = 17) stool samples by Real-time PCR. Results Absolute quantification of Bacteroides (p = .001), Closrtridium coccoides subgroup (p = 0.002), Clostridium leptum subgroup (p = 0.0001), Lactobacillus (p = 0.037), Campylobacter (p = 0.0014) and Eubacterium (p = 0.038) show significant drop in their population however, significant increase in Bifdobacterium (p = 0.009) was observed where as the population of Ruminococcus (p = 0.33) remained unaltered in healthy vs amebic patients (E. histolytica positive). We also report high prevalence of nimE gene in stool samples of both healthy volunteers and amebic patients. No significant decrease in nimE gene copy number was observed before and after the treatment with antiamebic drug. Conclusions Our results show significant alteration in predominant gut bacteria in E. histolytica infected individuals. The frequent episodes of intestinal amoebic dysentery thus result in depletion of few predominant genera in gut that may lead to poor digestion and absorption of food in intestine. It further disturbs the homeostasis

  18. Subgingival microbial profiles of Sudanese patients with aggressive periodontitis

    PubMed Central

    Elabdeen, H. R. Z.; Mustafa, M.; Hasturk, H.; Klepac-Ceraj, V.; Ali, R. W.; Paster, B. J.; Dyke, T. Van; Bolstad, A. I.

    2015-01-01

    Background and Objective Aggressive periodontitis (AgP) is prevalent and shows a rapid course in African individuals. Although a strong focus has been placed on Aggregatibacter actinomycetemcomitans, new methods support the existence of a complex subgingival microflora in AgP. The purpose of the present study was to map the subgingival microbiota as well as explore the presence of A. actinomycetemcomitans and the JP2 clone in a group of Sudanese individuals with AgP, using different analytical methods. Material and Methods A study population consisting of 19 patients with AgP was recruited from patients seeking treatment at University of Science and Technology (UST) in Khartoum. Fifteen healthy subjects were included as controls. Plaque samples were analyzed for 272 taxa using human oral microbe identification microarrays and for 26 periodontal taxa using DNA-DNA hybridization checkerboard. Conventional polymerase chain reaction (PCR) was applied for the detection of A. actinomycetemcomitans and the JP2 clone in plaque. Saliva from patients with AgP was analyzed using quantitative PCR (qPCR) for the detection of A. actinomycetemcomitans. Results Eubacterium yurii was detected more frequently in patients with AgP than in controls, and E. nodatum was found in patients with AgP only. A. actinomycetemcomitans was found in plaque samples of two (12%) patients by human oral microbe identification microarrays and in five (29%) patients with AgP by conventional PCR, as well as in six (32%) of the AgP saliva samples by qPCR. The JP2 clone was identified in only one patient. Conclusion The classical periodontal pathogens were not present in high amounts in AgP in the population studied here. Species of Eubacterium, which are not typically associated with AgP, were often detected in individuals with disease. Using laboratory methods with different sensitivities and detection levels allowed identification of variances in microbial communities. The findings reported in this

  19. The Galectin CvGal1 from the Eastern Oyster (Crassostrea virginica) Binds to Blood Group A Oligosaccharides on the Hemocyte Surface*

    PubMed Central

    Feng, Chiguang; Ghosh, Anita; Amin, Mohammed N.; Giomarelli, Barbara; Shridhar, Surekha; Banerjee, Aditi; Fernández-Robledo, José A.; Bianchet, Mario A.; Wang, Lai-Xi; Wilson, Iain B. H.; Vasta, Gerardo R.

    2013-01-01

    The galectin CvGal1 from the eastern oyster (Crassostrea virginica), which possesses four tandemly arrayed carbohydrate recognition domains, was previously shown to display stronger binding to galactosamine and N-acetylgalactosamine relative to d-galactose. CvGal1 expressed by phagocytic cells is “hijacked” by the parasite Perkinsus marinus to enter the host, where it proliferates and causes systemic infection and death. In this study, a detailed glycan array analysis revealed that CvGal1 preferentially recognizes type 2 blood group A oligosaccharides. Homology modeling of the protein and its oligosaccharide ligands supported this preference over type 1 blood group A and B oligosaccharides. The CvGal ligand models were further validated by binding, inhibition, and competitive binding studies of CvGal1 and ABH-specific monoclonal antibodies with intact and deglycosylated glycoproteins, hemocyte extracts, and intact hemocytes and by surface plasmon resonance analysis. A parallel glycomic study carried out on oyster hemocytes (Kurz, S., Jin, C., Hykollari, A., Gregorich, D., Giomarelli, B., Vasta, G. R., Wilson, I. B. H., and Paschinger, K. (2013) J. Biol. Chem. 288,) determined the structures of oligosaccharides recognized by CvGal1. Proteomic analysis of the hemocyte glycoproteins identified β-integrin and dominin as CvGal1 “self”-ligands. Despite strong CvGal1 binding to P. marinus trophozoites, no binding of ABH blood group antibodies was observed. Thus, parasite glycans structurally distinct from the blood group A oligosaccharides on the hemocyte surface may function as potentially effective ligands for CvGal1. We hypothesize that carbohydrate-based mimicry resulting from the host/parasite co-evolution facilitates CvGal1-mediated cross-linking to β-integrin, located on the hemocyte surface, leading to cell activation, phagocytosis, and host infection. PMID:23824193

  20. The evolution of tenascins and fibronectin

    PubMed Central

    Adams, Josephine C; Chiquet-Ehrismann, Ruth; Tucker, Richard P

    2015-01-01

    Tenascins are extracellular matrix glycoproteins that act both as integrin ligands and as modifiers of fibronectin-integrin interactions to regulate cell adhesion, migration, proliferation and differentiation. In tetrapods, both tenascins and fibronectin bind to integrins via RGD and LDV-type tripeptide motifs found in exposed loops in their fibronectin-type III domains. We previously showed that tenascins appeared early in the chordate lineage and are represented by single genes in extant cephalochordates and tunicates. Here we have examined the genomes of the coelacanth Latimeria chalumnae, the elephant shark Callorhinchus milii as well as the lampreys Petromyzon marinus and Lethenteron japonicum to learn more about the evolution of the tenascin gene family as well as the timing of the appearance of fibronectin during chordate evolution. The coelacanth has 4 tenascins that are more similar to tetrapod tenascins than are tenascins from ray-finned fishes. In contrast, only 2 tenascins were identified in the elephant shark and the Japanese lamprey L. japonicum. An RGD motif exposed to integrin binding is observed in tenascins from many, but not all, classes of chordates. Tetrapods that lack this RGD motif in tenascin-C have a similar motif in the paralog tenascin-W, suggesting the potential for some overlapping function. A predicted fibronectin with the same domain organization as the fibronectin from tetrapods is found in the sea lamprey P. marinus but not in tunicates, leading us to infer that fibronectin first appeared in vertebrates. The motifs that recognize LDV-type integrin receptors are conserved in fibronectins from a broad spectrum of vertebrates, but the RGD integrin-binding motif may have evolved in gnathostomes. PMID:25482621

  1. Active urea transport by the skin of Bufo viridis: Amiloride- and phloretin-sensitive transport sites

    SciTech Connect

    Rapoport, J.; Abuful, A.; Chaimovitz, C.; Noeh, Z.; Hays, R.M. Albert Einstein College of Medicine, New York, NY )

    1988-09-01

    Urea is actively transported inwardly (J{sub i}) across the skin of the green toad Bufo viridis. J{sub i} is markedly enhanced in toads adapted to hypertonic saline. The authors studied urea transport across the skin of Bufo viridis under a variety of experimental conditions, including treatment with amiloride and phloretin, agents that inhibit urea permeability in the bladder of Bufo marinus. Amiloride (10{sup {minus}4} M) significantly inhibited J{sub i} in both adapted and unadapted animals and was unaffected by removal of sodium from the external medium. Phloretin (10{sup {minus}4} M) significantly inhibited J{sub i} in adapted animals by 23-46%; there was also a reduction in J{sub i} in unadapted toads at 10{sup {minus}4} and 5 {times} 10{sup {minus}4} M phloretin. A dose-response study revealed that the concentration of phloretin causing half-maximal inhibition (K{sub {1/2}}) was 5 {times} 10{sup {minus}4} M for adapted animals. J{sub i} was unaffected by the substitution of sucrose for Ringer solution or by ouabain. They conclude (1) the process of adaptation appears to involve an increase in the number of amiloride- and phloretin-inhibitable urea transport sites in the skin, with a possible increase in the affinity of the sites for phloretin; (2) the adapted skin resembles the Bufo marinus urinary bladder with respect to amiloride and phloretin-inhibitable sites; (3) they confirm earlier observations that J{sub i} is independent of sodium transport.

  2. Phylogenetic relationships of marine bacteria, mainly members of the family Vibrionaceae, determined on the basis of 16S rRNA sequences.

    PubMed

    Kita-Tsukamoto, K; Oyaizu, H; Nanba, K; Simidu, U

    1993-01-01

    The phylogenetic relationships of 50 reference strains, mostly marine bacteria which require Na+ for growth, were determined on the basis of 600 16S rRNA nucleotides by using reverse transcriptase sequencing. Strains belonging to 10 genera were included (four genera of the family Vibrionaceae, the genus Aeromonas of the family Aeromonadaceae, and the genera Alteromonas, Marinomonas, Shewanella, Pseudomonas, and Deleya). The sequences were aligned, the similarity values and evolutionary distance values were determined, and a phylogenetic tree was constructed by using the neighbor-joining method. On the basis of our results, the family Vibrionaceae was separated into at least seven groups (genera and families). Vibrio marinus clearly was on a line of descent that was remote from other vibrios. As determined by the similarity and evolutionary distance values, V. marinus is more distantly related to the family Vibrionaceae than the members of the Aeromonadaceae are. Also, Vibrio cholerae strains formed a separate group with Vibrio mimicus at the genus level. Of 30 species of the Vibrionaceae, 17 formed a large phylogenetic cluster. The genus Listonella was found to be a heterogeneous group, and the species were distributed in various subgroups of the Vibrionaceae. The separation of the family Aeromonadaceae from the family Vibrionaceae and the separation of the genera Marinomonas and Shewanella from the genus Alteromonas were confirmed in this phylogenetic study. However, a marine Pseudomonas species, Pseudomonas nautica, was clearly separated from two terrestrial Pseudomonas species. Each group that was separated by the phylogenetic analysis had characteristic 16S rRNA sequence patterns that were common only to species in that group. Therefore, the characteristic sequences described in this paper may be useful for identification purposes. PMID:8427811

  3. Effect of water temperature on sea lamprey growth and lake trout survival

    SciTech Connect

    Swink, W.D. )

    1993-11-01

    Percent mortality of lake trout Salvelinus namaycush subjected to single sea lamprey Petromyzon marinus attacks did not differ significantly between lower-temperature (mortality = 54%; temperature [le] 10[degrees]C; N = 33) and higher-temperature (mortality = 69%; temperature = 12.8-14.4[degrees]C; N = 45) laboratory studies conducted from 1 June to 28 November 1989. However, sea lampreys fed longer and killed fewer fish in colder water (mean attachment 467.0 h; 18 fish killed) than in warmer water (mean attachment 161.7 h; 31 fish killed), probably because food consumption was lower in colder water. These results indicate that the number of fish killed by sea lampreys could be much greater in warmer water and that temperature must be considered when fish losses from sea lamprey attacks are estimated. Previous studies (Swink and Hanson 1989; Swink 1990) of the effects of single sea lamprey Petromyzon marinus attacks on lake trout Salvelinus namaycush showed significantly less lake trout mortality at temperatures of 10[degrees]C and lower than at higher temperatures. The reduced host mortality, however, could not be attributed solely to lower temperature because warmwater and coldwater attacks occurred during different seasons. In those studies, the author was unable to hold water temperature at 10[degrees]C or less in late summer and early fall, when most fish are killed by sea lampreys in the Great Lakes (Christie and Kolenosky 1980; Bergstedt and Schneider 1988). Modifications to the fish holding facilities at the Hammond Bay Biological Station in 1988 allowed maintenance of a limited amount of water at 10[degrees]C or less throughout the year. Hence, the objective of this study was to compare sea lamprey-induced mortality of lake trout at 10[degrees]C or less with that at 12.8-14.4[degrees]C during the normal feeding season (June through November). 15 refs., 1 fig., 1 tab.

  4. The evolution of tenascins and fibronectin.

    PubMed

    Adams, Josephine C; Chiquet-Ehrismann, Ruth; Tucker, Richard P

    2015-01-01

    Tenascins are extracellular matrix glycoproteins that act both as integrin ligands and as modifiers of fibronectin-integrin interactions to regulate cell adhesion, migration, proliferation and differentiation. In tetrapods, both tenascins and fibronectin bind to integrins via RGD and LDV-type tripeptide motifs found in exposed loops in their fibronectin-type III domains. We previously showed that tenascins appeared early in the chordate lineage and are represented by single genes in extant cephalochordates and tunicates. Here we have examined the genomes of the coelacanth Latimeria chalumnae, the elephant shark Callorhinchus milii as well as the lampreys Petromyzon marinus and Lethenteron japonicum to learn more about the evolution of the tenascin gene family as well as the timing of the appearance of fibronectin during chordate evolution. The coelacanth has 4 tenascins that are more similar to tetrapod tenascins than are tenascins from ray-finned fishes. In contrast, only 2 tenascins were identified in the elephant shark and the Japanese lamprey L. japonicum. An RGD motif exposed to integrin binding is observed in tenascins from many, but not all, classes of chordates. Tetrapods that lack this RGD motif in tenascin-C have a similar motif in the paralog tenascin-W, suggesting the potential for some overlapping function. A predicted fibronectin with the same domain organization as the fibronectin from tetrapods is found in the sea lamprey P. marinus but not in tunicates, leading us to infer that fibronectin first appeared in vertebrates. The motifs that recognize LDV-type integrin receptors are conserved in fibronectins from a broad spectrum of vertebrates, but the RGD integrin-binding motif may have evolved in gnathostomes. PMID:25482621

  5. Modestobacter caceresii sp. nov., novel actinobacteria with an insight into their adaptive mechanisms for survival in extreme hyper-arid Atacama Desert soils.

    PubMed

    Busarakam, Kanungnid; Bull, Alan T; Trujillo, Martha E; Riesco, Raul; Sangal, Vartul; van Wezel, Gilles P; Goodfellow, Michael

    2016-06-01

    A polyphasic study was designed to determine the taxonomic provenance of three Modestobacter strains isolated from an extreme hyper-arid Atacama Desert soil. The strains, isolates KNN 45-1a, KNN 45-2b(T) and KNN 45-3b, were shown to have chemotaxonomic and morphological properties in line with their classification in the genus Modestobacter. The isolates had identical 16S rRNA gene sequences and formed a branch in the Modestobacter gene tree that was most closely related to the type strain of Modestobacter marinus (99.6% similarity). All three isolates were distinguished readily from Modestobacter type strains by a broad range of phenotypic properties, by qualitative and quantitative differences in fatty acid profiles and by BOX fingerprint patterns. The whole genome sequence of isolate KNN 45-2b(T) showed 89.3% average nucleotide identity, 90.1% (SD: 10.97%) average amino acid identity and a digital DNA-DNA hybridization value of 42.4±3.1 against the genome sequence of M. marinus DSM 45201(T), values consistent with its assignment to a separate species. On the basis of all of these data, it is proposed that the isolates be assigned to the genus Modestobacter as Modestobacter caceresii sp. nov. with isolate KNN 45-2b(T) (CECT 9023(T)=DSM 101691(T)) as the type strain. Analysis of the whole-genome sequence of M. caceresii KNN 45-2b(T), with 4683 open reading frames and a genome size of ∽4.96Mb, revealed the presence of genes and gene-clusters that encode for properties relevant to its adaptability to harsh environmental conditions prevalent in extreme hyper arid Atacama Desert soils. PMID:27108251

  6. The galectin CvGal1 from the eastern oyster (Crassostrea virginica) binds to blood group A oligosaccharides on the hemocyte surface.

    PubMed

    Feng, Chiguang; Ghosh, Anita; Amin, Mohammed N; Giomarelli, Barbara; Shridhar, Surekha; Banerjee, Aditi; Fernández-Robledo, José A; Bianchet, Mario A; Wang, Lai-Xi; Wilson, Iain B H; Vasta, Gerardo R

    2013-08-23

    The galectin CvGal1 from the eastern oyster (Crassostrea virginica), which possesses four tandemly arrayed carbohydrate recognition domains, was previously shown to display stronger binding to galactosamine and N-acetylgalactosamine relative to d-galactose. CvGal1 expressed by phagocytic cells is "hijacked" by the parasite Perkinsus marinus to enter the host, where it proliferates and causes systemic infection and death. In this study, a detailed glycan array analysis revealed that CvGal1 preferentially recognizes type 2 blood group A oligosaccharides. Homology modeling of the protein and its oligosaccharide ligands supported this preference over type 1 blood group A and B oligosaccharides. The CvGal ligand models were further validated by binding, inhibition, and competitive binding studies of CvGal1 and ABH-specific monoclonal antibodies with intact and deglycosylated glycoproteins, hemocyte extracts, and intact hemocytes and by surface plasmon resonance analysis. A parallel glycomic study carried out on oyster hemocytes (Kurz, S., Jin, C., Hykollari, A., Gregorich, D., Giomarelli, B., Vasta, G. R., Wilson, I. B. H., and Paschinger, K. (2013) J. Biol. Chem. 288) determined the structures of oligosaccharides recognized by CvGal1. Proteomic analysis of the hemocyte glycoproteins identified β-integrin and dominin as CvGal1 "self"-ligands. Despite strong CvGal1 binding to P. marinus trophozoites, no binding of ABH blood group antibodies was observed. Thus, parasite glycans structurally distinct from the blood group A oligosaccharides on the hemocyte surface may function as potentially effective ligands for CvGal1. We hypothesize that carbohydrate-based mimicry resulting from the host/parasite co-evolution facilitates CvGal1-mediated cross-linking to β-integrin, located on the hemocyte surface, leading to cell activation, phagocytosis, and host infection. PMID:23824193

  7. Galectin CvGal2 from the Eastern Oyster (Crassostrea virginica) Displays Unique Specificity for ABH Blood Group Oligosaccharides and Differentially Recognizes Sympatric Perkinsus Species.

    PubMed

    Feng, Chiguang; Ghosh, Anita; Amin, Mohammed N; Bachvaroff, Tsvetan R; Tasumi, Satoshi; Pasek, Marta; Banerjee, Aditi; Shridhar, Surekha; Wang, Lai-Xi; Bianchet, Mario A; Vasta, Gerardo R

    2015-08-01

    Galectins are highly conserved lectins that are key to multiple biological functions, including pathogen recognition and regulation of immune responses. We previously reported that CvGal1, a galectin expressed in phagocytic cells (hemocytes) of the eastern oyster (Crassostrea virginica), is hijacked by the parasite Perkinsus marinus to enter the host, where it causes systemic infection and death. Screening of an oyster hemocyte cDNA library revealed a novel galectin, which we designated CvGal2, with four tandemly arrayed carbohydrate recognition domains (CRDs). Phylogentic analysis of the CvGal2 CRDs suggests close relationships with homologous CRDs from CvGal1. Glycan array analysis, however, revealed that, unlike CvGal1 which preferentially binds to the blood group A tetrasaccharide, CvGal2 recognizes both blood group A and B tetrasaccharides and related structures, suggesting that CvGal2 has broader binding specificity. Furthermore, SPR analysis demonstrated significant differences in the binding kinetics of CvGal1 and CvGal2, and structural modeling revealed substantial differences in their interactions with the oligosaccharide ligands. CvGal2 is homogeneously distributed in the hemocyte cytoplasm, is released to the extracellular space, and binds to the hemocyte surface. CvGal2 binds to P. marinus trophozoites in a dose-dependent and β-galactoside-specific manner. Strikingly, negligible binding of CvGal2 was observed for Perkinsus chesapeaki, a sympatric parasite species mostly prevalent in the clams Mya arenaria and Macoma balthica. The differential recognition of Perkinsus species by the oyster galectins is consistent with their relative prevalence in oyster and clam species and supports their role in facilitating parasite entry and infectivity in a host-preferential manner. PMID:26158802

  8. Salinity effects on viability, metabolic activity and proliferation of three Perkinsus species.

    PubMed

    La Peyre, Megan; Casas, Sandra; La Peyre, Jerome

    2006-07-11

    Little is known regarding the range of conditions in which many Perkinsus species may proliferate, making it difficult to predict conditions favorable for their expansion, to identify conditions inducing mortality, or to identify instances of potential cross-infectivity among sympatric host species. In this study, the effects of salinity on viability, metabolic activity and proliferation of P. marinus, P. olseni and P. chesapeaki were determined. Specifically, this research examined the effects of 5 salinities (7, 11, 15, 25, 35 per thousand), (1) without acclimation, on the viability and metabolic activity of 2 isolates of each Perkinsus species, and (2) with acclimation, on the viability, metabolic activity, size and number of 1 isolate of each species. P. chesapeaki showed the widest range of salinity tolerance of the 3 species, with high viability and cell proliferation at all salinities tested. Although P. chesapeaki originated from low salinity areas (i.e. <15 per thousand), several measures (i.e. cell number and metabolic activity) indicated that higher salinities (15, 25 per thousand) were more favorable for its growth. P. olseni, originating from high salinity areas, had better viability and proliferation at the higher salinities (15, 25, 35 per thousand). Distinct differences in acute salinity response of the 2 P. olseni isolates at lower salinities (7, 11 per thousand), however, suggest the need for a more expansive comparison of isolates to better define the lower salinity tolerance. Lastly, P. marinus was more tolerant of the lower salinities (7 and 11 per thousand) than P. olseni, but exhibited reduced viability at 7 per thousand, even after acclimation. PMID:16922001

  9. Influence of water allocation and freshwater inflow on oyster production: a hydrodynamic-oyster population model for Galveston Bay, Texas, USA.

    PubMed

    Powell, Eric N; Klinck, John M; Hofmann, Eileen E; McManus, Margaret A

    2003-01-01

    A hydrodynamic-oyster population model was developed to assess the effect of changes in freshwater inflow on oyster populations in Galveston Bay, Texas, USA. The population model includes the effects of environmental conditions, predators, and the oyster parasite, Perkinsus marinus, on oyster populations. The hydrodynamic model includes the effects of wind stress, river runoff, tides, and oceanic exchange on the circulation of the bay. Simulations were run for low, mean, and high freshwater inflow conditions under the present (1993) hydrology and predicted hydrologies for 2024 and 2049 that include both changes in total freshwater inflow and diversions of freshwater from one primary drainage basin to another. Freshwater diversion to supply the Houston metropolitan area is predicted to negatively impact oyster production in Galveston Bay. Fecundity and larval survivorship both decline. Mortality from Perkinsus marinus increases, but to a lesser extent. A larger negative impact in 2049 relative to 2024 originates from the larger drop in fecundity under that hydrology. Changes in recruitment and mortality, resulting in lowered oyster abundance, occur because the bay volume available for mixing freshwater input from the San Jacinto and Buffalo Bayou drainage basins that drain metropolitan Houston is small in comparison to the volume of Trinity Bay that presently receives the bulk of the bay's freshwater inflow. A smaller volume for mixing results in salinities that decline more rapidly and to a greater extent under conditions of high freshwater discharge.Thus, the decline in oyster abundance results from a disequilibrium between geography and salinity brought about by freshwater diversion. Although the bay hydrology shifts, available hard substrate does not. The simulations stress the fact that it is not just the well-appreciated reduction in freshwater inflow that can result in decreased oyster production. Changing the location of freshwater inflow can also

  10. Infertility in a marine crustacean: have we been ignoring pollution impacts on male invertebrates?

    PubMed

    Yang, Gongda; Kille, Peter; Ford, Alex T

    2008-06-01

    Invertebrate infertility has been under-explored as a potential ecological issue or biomarker of stress within ecotoxicology. To date, the majority of studies focussing on contaminant induced infertility have centred on vertebrate groups. This study aimed to address the question whether industrial pollution has the ability to influence the sperm counts and testicular morphology of male amphipod, Echinogammarus marinus (Leach). In addition, the sperm counts of normal and intersex specimens were compared to assess the potential impact of a crustacean with a disrupted endocrine system. Specimens of E. marinus were collected at one industrially impacted (Inverkeithing) and two reference (Thurso and Loch Fleet) sites along the north and eastern coasts of Scotland. Significantly higher sperm counts ( approximately 20%) were observed from normal males collected from reference sites compared to the industrially impacted site. Higher proportions (30%) of intersex specimens were observed at the industrially impacted site compared to 17 and 6% male intersexuality observed at Thurso and Loch Fleet, respectively. Intersex male specimens from Thurso had lower mean sperm counts ( approximately 15%) than normal male specimens, however, this result was not significant (P=0.089). No significant differences in sperm counts were observed between normal and intersex males at Inverkeithing. Our results indicate that industrial pollution does have the potential to affect the sperm counts of male crustaceans. Whether the quality of sperm in Crustacea from contaminated sites is also compromised or whether this is an endocrine mediated effect is yet to be confirmed. To date, many of the studies of endocrine disruption in crustaceans have, surprisingly, focussed on female fecundity parameters, growth and moulting despite many of the vertebrate studies initially focussing on the male gender. Whether this could be an ecological issue needs to be addressed through further field and laboratory

  11. Cloning, sequence analysis and three-dimensional structure prediction of DNA pol I from thermophilic Geobacillus sp. MKK isolated from an Iranian hot spring.

    PubMed

    Khalaj-Kondori, Mohammad; Sadeghizadeh, Majid; Khajeh, Khosro; Naderi-Manesh, Hossein; Ahadi, Ali Mohammad; Emamzadeh, Abdorahman

    2007-08-01

    Molecular phylogenetic analysis of a novel thermophilic eubacterium isolated from an Iranian hot spring using 16S rDNA sequence showed that the new isolate belongs to genera Geobacillus. DNA pol I gene from this isolate was amplified, cloned, sequenced, and the three-dimensional (3D) structure of deduced amino acid sequence was predicted. Sequence analysis revealed the gene is 2,631 bp long, encodes a protein of 876 amino acids with a calculated molecular mass of 99 kDa, and belongs to family A DNA polymerases. Comparison of 3'-5'exonuclease domain of Klenow fragment (KF) with corresponding region of newly identified DNA pol I (MF), the large fragment of Bacillus stearothermophilus DNA pol I (BF) and Klentaq1, revealed not only deletions in three regions compared to KF, but that three of the four critical metal-binding residues in KF (Asp355, Glu357, Asp424, and Asp501) are altered in MF as well. Predicted 3D structure and sequence alignments between MF and BF showed that all critical residues in the polymerase active site are conserved. PMID:18025581

  12. Detection of Sialic Acid-Utilising Bacteria in a Caecal Community Batch Culture Using RNA-Based Stable Isotope Probing

    PubMed Central

    Young, Wayne; Egert, Markus; Bassett, Shalome A.; Bibiloni, Rodrigo

    2015-01-01

    Sialic acids are monosaccharides typically found on cell surfaces and attached to soluble proteins, or as essential components of ganglioside structures that play a critical role in brain development and neural transmission. Human milk also contains sialic acid conjugated to oligosaccharides, glycolipids, and glycoproteins. These nutrients can reach the large bowel where they may be metabolised by the microbiota. However, little is known about the members of the microbiota involved in this function. To identify intestinal bacteria that utilise sialic acid within a complex intestinal community, we cultured the caecal microbiota from piglets in the presence of 13C-labelled sialic acid. Using RNA-based stable isotope probing, we identified bacteria that consumed 13C-sialic acid by fractionating total RNA in isopycnic buoyant density gradients followed by 16S rRNA gene analysis. Addition of sialic acid caused significant microbial community changes. A relative rise in Prevotella and Lactobacillus species was accompanied by a corresponding reduction in the genera Escherichia/Shigella, Ruminococcus and Eubacterium. Inspection of isotopically labelled RNA sequences suggests that the labelled sialic acid was consumed by a wide range of bacteria. However, species affiliated with the genus Prevotella were clearly identified as the most prolific users, as solely their RNA showed significantly higher relative shares among the most labelled RNA species. Given the relevance of sialic acid in nutrition, this study contributes to a better understanding of their microbial transformation in the intestinal tract with potential implications for human health. PMID:25816158

  13. Quantitative bacteriology of the vaginal flora.

    PubMed

    Bartlett, J G; Onderdonk, A B; Drude, E; Goldstein, C; Anderka, M; Alpert, S; McCormack, W M

    1977-08-01

    Quantitative bacteriology was performed on vaginal secretions from healthy adult women. The analysis included a single sample from 17 college students and 35 samples from five volunteers collected at intervals of three to five days throughout the menstrual cycle. Mean concentrations in all 52 specimens were 10(8.1) aerobic bacteria/g and 10(9.1) anaerobic bacteria/g. The rank of predominant organisms, according to rates of recovery in concentrations of greater than 10(5) colony-forming units/g, was anaerobic and facultative Lacrobacillus species, Peptococcus species, Bacteroides species, Staphylococcus epidermidis, Corynebacterium species, Peotostreptococcus species, and Eubacterium species. Sequential samples collected throughout the menstrual cycle showed relatively consistent mean levels of anaerobes and a significant decrease in concentrations of aerobes in premenstrual specimens compared with those in the specimens collected in the week following onset of menses. Analysis of sequential specimens from each of the five individuals showed considerable variation in species recovered. These data indicate that the vaginal flora in healthy adult women is a dynamic ecosystem in which anaerobes are usually the numerically dominant bacteria. PMID:894079

  14. Frequency, microbial interactions, and antimicrobial susceptibility of Fusobacterium nucleatum and Fusobacterium necrophorum isolated from primary endodontic infections.

    PubMed

    Jacinto, Rogério C; Montagner, Francisco; Signoretti, Fernanda G C; Almeida, Geovania C; Gomes, Brenda P F A

    2008-12-01

    This study assessed the prevalence and microbial interactions of Fusobacterium nucleatum and Fusobacterium necrophorum in primary endodontic infections from a Brazilian population and their antimicrobial susceptibility to some antibiotics by the E-test. One hundred ten samples from infected teeth with periapical pathologies were analyzed by culture methods. Five hundred eighty individual strains were isolated; 81.4% were strict anaerobes. F. nucleatum was found in 38 root canals and was associated with Porphyromonas gingivalis, Prevotella spp., and Eubacterium spp. F. necrophorum was found in 20 root canals and was associated with Peptostreptococcus prevotii. The simultaneous presence of F. nucleatum and F. necrophorum was not related to endodontic symptoms (p > 0.05). They were 100% susceptible to amoxicillin, amoxicillin/clavulanate, and cephaclor. Fusobacterium spp. is frequently isolated from primary-infected root canals of teeth with periapical pathologies. Amoxicillin is a useful antibiotic against F. nucleatum and F. necrophorum in endodontic infections and has been prescribed as the first choice in Brazil. PMID:19026872

  15. Diet rapidly and reproducibly alters the human gut microbiome

    PubMed Central

    David, Lawrence A.; Maurice, Corinne F.; Carmody, Rachel N.; Gootenberg, David B.; Button, Julie E.; Wolfe, Benjamin E.; Ling, Alisha V.; Devlin, A. Sloan; Varma, Yug; Fischbach, Michael A.; Biddinger, Sudha B.; Dutton, Rachel J.; Turnbaugh, Peter J.

    2013-01-01

    Long-term diet influences the structure and activity of the trillions of microorganisms residing in the human gut1–5, but it remains unclear how rapidly and reproducibly the human gut microbiome responds to short-term macronutrient change. Here, we show that the short-term consumption of diets composed entirely of animal or plant products alters microbial community structure and overwhelms inter-individual differences in microbial gene expression. The animal-based diet increased the abundance of bile-tolerant microorganisms (Alistipes, Bilophila, and Bacteroides) and decreased the levels of Firmicutes that metabolize dietary plant polysaccharides (Roseburia, Eubacterium rectale, and Ruminococcus bromii). Microbial activity mirrored differences between herbivorous and carnivorous mammals2, reflecting trade-offs between carbohydrate and protein fermentation. Foodborne microbes from both diets transiently colonized the gut, including bacteria, fungi, and even viruses. Finally, increases in the abundance and activity of Bilophila wadsworthia on the animal-based diet support a link between dietary fat, bile acids, and the outgrowth of microorganisms capable of triggering inflammatory bowel disease6. In concert, these results demonstrate that the gut microbiome can rapidly respond to altered diet, potentially facilitating the diversity of human dietary lifestyles. PMID:24336217

  16. Impact of dietary resistant starch type 4 on human gut microbiota and immunometabolic functions

    PubMed Central

    Upadhyaya, Bijaya; McCormack, Lacey; Fardin-Kia, Ali Reza; Juenemann, Robert; Nichenametla, Sailendra; Clapper, Jeffrey; Specker, Bonny; Dey, Moul

    2016-01-01

    Dietary modulation of the gut microbiota impacts human health. Here we investigated the hitherto unknown effects of resistant starch type 4 (RS4) enriched diet on gut microbiota composition and short-chain fatty acid (SCFA) concentrations in parallel with host immunometabolic functions in twenty individuals with signs of metabolic syndrome (MetS). Cholesterols, fasting glucose, glycosylated haemoglobin, and proinflammatory markers in the blood as well as waist circumference and % body fat were lower post intervention in the RS4 group compared with the control group. 16S-rRNA gene sequencing revealed a differential abundance of 71 bacterial operational taxonomic units, including the enrichment of three Bacteroides species and one each of Parabacteroides, Oscillospira, Blautia, Ruminococcus, Eubacterium, and Christensenella species in the RS4 group. Gas chromatography–mass spectrometry revealed higher faecal SCFAs, including butyrate, propionate, valerate, isovalerate, and hexanoate after RS4-intake. Bivariate analyses showed RS4-specific associations of the gut microbiota with the host metabolic functions and SCFA levels. Here we show that dietary RS4 induced changes in the gut microbiota are linked to its biological activity in individuals with signs of MetS. These findings have potential implications for dietary guidelines in metabolic health management. PMID:27356770

  17. Diet rapidly and reproducibly alters the human gut microbiome.

    PubMed

    David, Lawrence A; Maurice, Corinne F; Carmody, Rachel N; Gootenberg, David B; Button, Julie E; Wolfe, Benjamin E; Ling, Alisha V; Devlin, A Sloan; Varma, Yug; Fischbach, Michael A; Biddinger, Sudha B; Dutton, Rachel J; Turnbaugh, Peter J

    2014-01-23

    Long-term dietary intake influences the structure and activity of the trillions of microorganisms residing in the human gut, but it remains unclear how rapidly and reproducibly the human gut microbiome responds to short-term macronutrient change. Here we show that the short-term consumption of diets composed entirely of animal or plant products alters microbial community structure and overwhelms inter-individual differences in microbial gene expression. The animal-based diet increased the abundance of bile-tolerant microorganisms (Alistipes, Bilophila and Bacteroides) and decreased the levels of Firmicutes that metabolize dietary plant polysaccharides (Roseburia, Eubacterium rectale and Ruminococcus bromii). Microbial activity mirrored differences between herbivorous and carnivorous mammals, reflecting trade-offs between carbohydrate and protein fermentation. Foodborne microbes from both diets transiently colonized the gut, including bacteria, fungi and even viruses. Finally, increases in the abundance and activity of Bilophila wadsworthia on the animal-based diet support a link between dietary fat, bile acids and the outgrowth of microorganisms capable of triggering inflammatory bowel disease. In concert, these results demonstrate that the gut microbiome can rapidly respond to altered diet, potentially facilitating the diversity of human dietary lifestyles. PMID:24336217

  18. Composition, taxonomy and functional diversity of the oropharynx microbiome in individuals with schizophrenia and controls

    PubMed Central

    Bendall, Matthew L.; Pérez-Losada, Marcos; Sabuncyan, Sarven; Severance, Emily G.; Dickerson, Faith B.; Schroeder, Jennifer R.; Yolken, Robert H.; Crandall, Keith A.

    2015-01-01

    The role of the human microbiome in schizophrenia remains largely unexplored. The microbiome has been shown to alter brain development and modulate behavior and cognition in animals through gut-brain connections, and research in humans suggests that it may be a modulating factor in many disorders. This study reports findings from a shotgun metagenomic analysis of the oropharyngeal microbiome in 16 individuals with schizophrenia and 16 controls. High-level differences were evident at both the phylum and genus levels, with Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria dominating both schizophrenia patients and controls, and Ascomycota being more abundant in schizophrenia patients than controls. Controls were richer in species but less even in their distributions, i.e., dominated by fewer species, as opposed to schizophrenia patients. Lactic acid bacteria were relatively more abundant in schizophrenia, including species of Lactobacilli and Bifidobacterium, which have been shown to modulate chronic inflammation. We also found Eubacterium halii, a lactate-utilizing species. Functionally, the microbiome of schizophrenia patients was characterized by an increased number of metabolic pathways related to metabolite transport systems including siderophores, glutamate, and vitamin B12. In contrast, carbohydrate and lipid pathways and energy metabolism were abundant in controls. These findings suggest that the oropharyngeal microbiome in individuals with schizophrenia is significantly different compared to controls, and that particular microbial species and metabolic pathways differentiate both groups. Confirmation of these findings in larger and more diverse samples, e.g., gut microbiome, will contribute to elucidating potential links between schizophrenia and the human microbiota. PMID:26336637

  19. Studies on mixed populations of human intestinal bacteria grown in single-stage and multistage continuous culture systems.

    PubMed Central

    Allison, C; McFarlan, C; MacFarlane, G T

    1989-01-01

    Mixed intestinal bacteria were grown for 336 h in two identical single-stage chemostats at low growth rates in a carbohydrate-limited medium. Complex bacterial populations were maintained and anaerobes always outnumbered aerobes. The predominant organisms belonged to the genera Bacteroides, Bifidobacterium, Lactobacillus, Clostridium, Eubacterium, Propionbacterium, Peptococcus, and Peptostreptococcus. Bacteroides species predominated in both fermentors, particularly B. ovatus and B. thetaiotaomicron. A high degree of reproducibility of bacteriological and fermentation product data was obtained in these experiments. When gut contents were inoculated into a five-stage continuous culture system (retention time of 79 or 38 h) containing soya bran, the medium flow rate had little quantitative effect on the formation of acidic fermentation products; however, more oxidized fermentation acids were produced at the higher retention time. Diverse bacterial populations were maintained in every vessel at each flow rate. Bacteroides fragilis group organisms, especially B. ovatus, were numerically the most important. The viability of bacteria decreased through the system, especially at a retention time of 79 h, when the bacteria were growing under severely nutrient-limited conditions. PMID:2930171

  20. Animal model for anaerobic lung abscess.

    PubMed Central

    Kannangara, D W; Thadepalli, H; Bach, V T; Webb, D

    1981-01-01

    There are no satisfactory animal models for the study of anaerobic lung abscess. Aspiration of food, gastric mucin, or hydrochloric acid, or any combination of these, along with oropharyngeal bacteria, is commonly believed to cause aspiration pneumonia and lung abscess. In the animal model described, none of the adjuvants was effective in producing anaerobic lung abscesses. Anaerobic bacteria derived from dental scrapings of a healthy adult (Peptococcus morbillorum, Fusobacterium nucleatum, Eubacterium lentum, and Bacteroides fragilis), when inoculated transtracheally without any adjuvants into New Zealand male white rabbits, consistently produced lung abscesses. Neither B fragilis by itself nor a mixture of P. morbillorum, F. nucleatum, and E. lentum without the addition of B. fragilis produced lung abscesses. The bacterial isolates used in this study were stored in prereduced chopped-meat-glucose medium and subcultured several times and were found effective in reproducing anaerobic lung abscesses repeatedly. This animal model is suitable for the study of pathogenesis, diagnosis, and treatment of B. fragilis-associated anaerobic lung abscess. Images PMID:7216463

  1. Phylogenetic and functional gene structure shifts of the oral microbiomes in periodontitis patients

    PubMed Central

    Li, Yan; He, Jinzhi; He, Zhili; Zhou, Yuan; Yuan, Mengting; Xu, Xin; Sun, Feifei; Liu, Chengcheng; Li, Jiyao; Xie, Wenbo; Deng, Ye; Qin, Yujia; VanNostrand, Joy D; Xiao, Liying; Wu, Liyou; Zhou, Jizhong; Shi, Wenyuan; Zhou, Xuedong

    2014-01-01

    Determining the composition and function of subgingival dental plaque is crucial to understanding human periodontal health and disease, but it is challenging because of the complexity of the interactions between human microbiomes and human body. Here, we examined the phylogenetic and functional gene differences between periodontal and healthy individuals using MiSeq sequencing of 16S rRNA gene amplicons and a specific functional gene array (a combination of GeoChip 4.0 for biogeochemical processes and HuMiChip 1.0 for human microbiomes). Our analyses indicated that the phylogenetic and functional gene structure of the oral microbiomes were distinctly different between periodontal and healthy groups. Also, 16S rRNA gene sequencing analysis indicated that 39 genera were significantly different between healthy and periodontitis groups, and Fusobacterium, Porphyromonas, Treponema, Filifactor, Eubacterium, Tannerella, Hallella, Parvimonas, Peptostreptococcus and Catonella showed higher relative abundances in the periodontitis group. In addition, functional gene array data showed that a lower gene number but higher signal intensity of major genes existed in periodontitis, and a variety of genes involved in virulence factors, amino acid metabolism and glycosaminoglycan and pyrimidine degradation were enriched in periodontitis, suggesting their potential importance in periodontal pathogenesis. However, the genes involved in amino acid synthesis and pyrimidine synthesis exhibited a significantly lower relative abundance compared with healthy group. Overall, this study provides new insights into our understanding of phylogenetic and functional gene structure of subgingival microbial communities of periodontal patients and their importance in pathogenesis of periodontitis. PMID:24671083

  2. Decreased Diversity of the Oral Microbiota of Patients with Hepatitis B Virus-Induced Chronic Liver Disease: A Pilot Project.

    PubMed

    Ling, Zongxin; Liu, Xia; Cheng, Yiwen; Jiang, Xiawei; Jiang, Haiyin; Wang, Yuezhu; Li, Lanjuan

    2015-01-01

    Increasing evidence suggests that altered gut microbiota is implicated in the pathogenesis of hepatitis B virus-induced chronic liver disease (HBV-CLD). However, the structure and composition of the oral microbiota of patients with HBV-CLD remains unclear. High-throughput pyrosequencing showed that decreased oral bacterial diversity was found in patients with HBV-CLD. The Firmicutes/Bacteroidetes ratio was increased significantly, which indicated that dysbiosis of the oral microbiota participated in the process of HBV-CLD development. However, the changing patterns of the oral microbiota in patients with HBV-induced liver cirrhosis (LC) were almost similar to patients with chronic hepatitis B (CHB). HBV infection resulted in an increase in potential H2S- and CH3SH-producing phylotypes such as Fusobacterium, Filifactor, Eubacterium, Parvimonas and Treponema, which might contribute to the increased oral malodor. These key oral-derived phylotypes might invade into the gut as opportunistic pathogens and contribute to altering the composition of the gut microbiota. This study provided important clues that dysbiosis of the oral microbiota might be involved in the development of HBV-CLD. Greater understanding of the relationships between the dysbiosis of oral microbiota and the development of HBV-CLD might facilitate the development of non-invasive differential diagnostic procedures and targeted treatments of HBV-CLD patients harbouring specific oral phylotypes. PMID:26606973

  3. Collateral damage from oral ciprofloxacin versus nitrofurantoin in outpatients with urinary tract infections: a culture-free analysis of gut microbiota.

    PubMed

    Stewardson, A J; Gaïa, N; François, P; Malhotra-Kumar, S; Delémont, C; Martinez de Tejada, B; Schrenzel, J; Harbarth, S; Lazarevic, V

    2015-04-01

    Recent treatment guidelines for uncomplicated urinary tract infections (UTIs) discourage fluoroquinolone prescription because of collateral damage to commensal microbiota, but the ecologic impact of alternative agents has not been evaluated by culture-free techniques. We prospectively collected faecal samples at three time points from ambulatory patients with UTIs treated with ciprofloxacin or nitrofurantoin, patients not requiring antibiotics and household contacts of ciprofloxacin-treated patients. We described changes in gut microbiota using a culture-independent approach based on pyrosequencing of the V3-V4 region of the bacterial 16S rRNA gene. All groups were similar at baseline. Ciprofloxacin had a significant global impact on the gut microbiota whereas nitrofurantoin did not. The end of ciprofloxacin treatment correlated with a reduced proportion of Bifidobacterium (Actinobacteria), Alistipes (Bacteroidetes) and four genera from the phylum Firmicutes (Faecalibacterium, Oscillospira, Ruminococcus and Dialister) and an increased relative abundance of Bacteroides (Bacteroidetes) and the Firmicutes genera Blautia, Eubacterium and Roseburia. Substantial recovery had occurred 4 weeks later. Nitrofurantoin treatment correlated with a reduced relative proportion of the genus Clostridium and an increased proportion of the genus Faecalibacterium. This study supports use of nitrofurantoin over fluoroquinolones for treatment of uncomplicated UTIs to minimize perturbation of intestinal microbiota. PMID:25658522

  4. The deconjugation ability of bacteria isolated from the jejunal fluids in the blind loop syndrome with high sup 14 CO sub 2 excretion. Using the breath analysis technique and thin-layer chromatography

    SciTech Connect

    Shindo, K.; Yamazaki, R.; Mizuno, T.; Shionoiri, H.; Sugiyama, M. )

    1989-01-01

    Five patients with blind loop syndrome (Billroth II) were examined by measuring {sup 14}CO{sub 2} specific activity of expired breath samples taken at intervals after a meal containing glycine-1-{sup 14}C cholate. The 5 patients tested showed a marked increase of {sup 14}CO{sub 2} specific activity. Furthermore, the ability of deconjugation of bacteria isolated from the jejunal fluids in the efferent loop of these patients was tested by thin-layer chromatography. The bacterial species identified from the samples were as follows: enterococcus, Lactobacillus buchneri, L. bifidus, L. brevis, Eubacterium lentum, Bacteroides vulgaricus, B. filamentosum, Corynebacterium granulosum, Escherichia coli, Staphylococcus epidermidis, and Aerobacter aerogenes. These species of bacteria, except E. coli and A. aerogenes, showed the deconjugation ability by which conjugated bile acids in ox gall was hydrolyzed. Administration of chloramphenicol to the 5 patients reduced {sup 14}CO{sub 2} specific activity significantly. On the other hand, 9 healthy men who were tested showed a flat curve, and 8 of the 9 had no growth of bacteria isolated from the jejunal fluids. The remaining healthy man showed an over growth of E. coli and Pseudomonas aeruginosa, but the species did not have the ability of deconjugation.

  5. In vitro fermentation of lupin seeds (Lupinus albus) and broad beans (Vicia faba): dynamic modulation of the intestinal microbiota and metabolomic output.

    PubMed

    Gullón, Patricia; Gullón, Beatriz; Tavaria, Freni; Vasconcelos, Marta; Gomes, Ana Maria

    2015-10-01

    Broad beans (Vicia faba) and lupin seeds (Lupinus albus) are legumes rich in a wide range of compounds, which may represent a useful dietary approach for modulating the human gut microbiome. In this work, after in vitro digestion, legume samples were used as carbon sources in anaerobic batch cultures to evaluate their impact on the intestinal microbiota composition and on their metabolic products. The fermentations were monitored by a decrease in pH, generation of short chain fatty acids (SCFA) and lactate and the changes in the dynamic bacterial populations by fluorescence in situ hybridization (FISH). The total SCFA at the end of fermentation was 81.52 mM for lupin seeds and 78.41 mM for broad beans accompanied by a decrease of the pH for both legumes. The microbial groups that increased significantly (P < 0.05) were Bifidobacterium spp., Lactobacillus-Enterococcus, Atopobium, Bacteroides-Pretovella, Clostridium coccoides-Eubacterium rectale, Faecalibacterium prausnitzii and Roseburia intestinalis. This impact on the intestinal microbiota suggests that lupin seeds and broad beans may be used in the development of novel functional foods, which can be included in dietary strategies for human health promotion. PMID:26252418

  6. In vitro colonic metabolism of coffee and chlorogenic acid results in selective changes in human faecal microbiota growth.

    PubMed

    Mills, Charlotte E; Tzounis, Xenofon; Oruna-Concha, Maria-Jose; Mottram, Don S; Gibson, Glenn R; Spencer, Jeremy P E

    2015-04-28

    Coffee is a relatively rich source of chlorogenic acids (CGA), which, as other polyphenols, have been postulated to exert preventive effects against CVD and type 2 diabetes. As a considerable proportion of ingested CGA reaches the large intestine, CGA may be capable of exerting beneficial effects in the large gut. Here, we utilise a stirred, anaerobic, pH-controlled, batch culture fermentation model of the distal region of the colon in order to investigate the impact of coffee and CGA on the growth of the human faecal microbiota. Incubation of coffee samples with the human faecal microbiota led to the rapid metabolism of CGA (4 h) and the production of dihydrocaffeic acid and dihydroferulic acid, while caffeine remained unmetabolised. The coffee with the highest levels of CGA (P<0·05, relative to the other coffees) induced a significant increase in the growth of Bifidobacterium spp. relative to the control vessel at 10 h after exposure (P<0·05). Similarly, an equivalent quantity of CGA (80·8 mg, matched with that in high-CGA coffee) induced a significant increase in the growth of Bifidobacterium spp. (P<0·05). CGA alone also induced a significant increase in the growth of the Clostridium coccoides-Eubacterium rectale group (P<0·05). This selective metabolism and subsequent amplification of specific bacterial populations could be beneficial to host health. PMID:25809126

  7. Direct Analysis of Genes Encoding 16S rRNA from Complex Communities Reveals Many Novel Molecular Species within the Human Gut

    PubMed Central

    Suau, Antonia; Bonnet, Régis; Sutren, Malène; Godon, Jean-Jacques; Gibson, Glenn R.; Collins, Matthew D.; Doré, Joel

    1999-01-01

    The human intestinal tract harbors a complex microbial ecosystem which plays a key role in nutrition and health. Although this microbiota has been studied in great detail by culture techniques, microscopic counts on human feces suggest that 60 to 80% of the observable bacteria cannot be cultivated. Using comparative analysis of cloned 16S rRNA gene (rDNA) sequences, we have investigated the bacterial diversity (both cultivated and noncultivated bacteria) within an adult-male fecal sample. The 284 clones obtained from 10-cycle PCR were classified into 82 molecular species (at least 98% similarity). Three phylogenetic groups contained 95% of the clones: the Bacteroides group, the Clostridium coccoides group, and the Clostridium leptum subgroup. The remaining clones were distributed among a variety of phylogenetic clusters. Only 24% of the molecular species recovered corresponded to described organisms (those whose sequences were available in public databases), and all of these were established members of the dominant human fecal flora (e.g., Bacteroides thetaiotaomicron, Fusobacterium prausnitzii, and Eubacterium rectale). However, the majority of generated rDNA sequences (76%) did not correspond to known organisms and clearly derived from hitherto unknown species within this human gut microflora. PMID:10543789

  8. Bacterial origin recognition complexes direct assembly of higher-order DnaA oligomeric structures.

    PubMed

    Miller, Diana T; Grimwade, Julia E; Betteridge, Thu; Rozgaja, Tania; Torgue, Julien J-C; Leonard, Alan C

    2009-11-01

    Eukaryotic initiator proteins form origin recognition complexes (ORCs) that bind to replication origins during most of the cell cycle and direct assembly of prereplication complexes (pre-RCs) before the onset of S phase. In the eubacterium Escherichia coli, there is a temporally similar nucleoprotein complex comprising the initiator protein DnaA bound to three high-affinity recognition sites in the unique origin of replication, oriC. At the time of initiation, this high-affinity DnaA-oriC complex (the bacterial ORC) accumulates additional DnaA that interacts with lower-affinity sites in oriC, forming a pre-RC. In this paper, we investigate the functional role of the bacterial ORC and examine whether it mediates low-affinity DnaA-oriC interactions during pre-RC assembly. We report that E. coli ORC is essential for DnaA occupation of low-affinity sites. The assistance given by ORC is directed primarily to proximal weak sites and requires oligomerization-proficient DnaA. We propose that in bacteria, DnaA oligomers of limited length and stability emerge from single high-affinity sites and extend toward weak sites to facilitate their loading as a key stage of prokaryotic pre-RC assembly. PMID:19833870

  9. Long-term monitoring of the human intestinal microbiota from the 2nd week to 13 years of age.

    PubMed

    Endo, Akihito; Pӓrtty, Anna; Kalliomӓki, Marko; Isolauri, Erika; Salminen, Seppo

    2014-08-01

    Microbial contact begins prior to birth and continues rapidly thereafter. Few long term follow-up studies have been reported and we therefore characterized the development of intestinal microbiota of ten subjects from the 2nd week of life to 13 years of age. PCR-denaturing gradient gel electrophoresis combined with several bacterial group-specific primer sets demonstrated the colonization steps of defined bacterial groups in the microbiota. Bifidobacterium species were seen throughout the test period in all subjects. Bacteroides fragilis group and Blautia coccoides-Eubacterium rectale group species were not detected in several subjects during the first 6 months of life but were commonly seen after 12 months of life. Streptococcus group appeared during early life but was not seen in several subjects at the age of 13 years. Although a few species were linked with the increasing age, major bacterial species in the groups did not change dramatically. Rather considerable changes were found in the relative abundances of each bacterial species. Clustering analysis of total bacterial flora indicated that the microbiota changed considerably between 6 months and 12 months of life, and, at the age of 12 months, the intestinal microbiota was already converted toward a profile characteristic of an adult microbiota. Probiotic supplementation in the beginning of life did not have major impacts on later microbiota development. PMID:24933584

  10. Isolation and partial sequence of the A-protein gene of Thermus thermophilus cytochrome c/sub 1/aa/sub 3/

    SciTech Connect

    Fee, J.A.; Mather, M.W.; Springer, P.; Hensel, S.; Buse, G.

    1988-01-01

    Thermus thermophilus is a strictly aerobic eubacterium which grows optimally near 70/degree/C. Its respiratory system is very similar to that of eukaryotic mitochondria, and the organism has proven to be a particularly good source of stable, comparatively simple respiratory enzymes. There are at least two terminal oxidases: The recently discovered cytochrome ba/sub 3//sup 3/ and cytochrome c/sub 1/aa/sub 3//sup 2/. Cytochrome ba/sub 3/ is analog of aa/sub 3/ in which the heme A of cytochrome a is replaced with protoporphyrin IX (heme B) while its order redox components appear to be largely identical to those of the now classical mammalian cytochrome aa/sub 3/; it has only a single 35 kD protein subunit. Cytochrome c/sub 1/aa/sub 3/ consists of two polypeptides. The /approximately/33 kD C-protein covalently binds one heme C, while the /approximately/55 kD protein is thought to bind the four canonical redox centers of aa/sub 3/, two heme A, and two Cu. Toward our goal of unequivocally establishing the distribution of the metal centers in cytochrome c/sub 1/aa/sub 3/, we have isolated the structural gene of the A-protein. 20 refs., 4 figs.

  11. Structure of trigger factor binding domain in biologically homologous complex with eubacterial ribosome reveals its chaperone action

    SciTech Connect

    Baram, David; Pyetan, Erez; Sittner, Assa; Auerbach-Nevo, Tamar; Bashan, Anat; Yonath, Ada

    2010-07-13

    Trigger factor (TF), the first chaperone in eubacteria to encounter the emerging nascent chain, binds to the large ribosomal subunit in the vicinity of the protein exit tunnel opening and forms a sheltered folding space. Here, we present the 3.5-{angstrom} crystal structure of the physiological complex of the large ribosomal subunit from the eubacterium Deinococcus radiodurans with the N-terminal domain of TF (TFa) from the same organism. For anchoring, TFa exploits a small ribosomal surface area in the vicinity of proteins L23 and L29, by using its 'signature motif' as well as additional structural elements. The molecular details of TFa interactions reveal that L23 is essential for the association of TF with the ribosome and may serve as a channel of communication with the nascent chain progressing in the tunnel. L29 appears to induce a conformational change in TFa, which results in the exposure of TFa hydrophobic patches to the opening of the ribosomal exit tunnel, thus increasing its affinity for hydrophobic segments of the emerging nascent polypeptide. This observation implies that, in addition to creating a protected folding space for the emerging nascent chain, TF association with the ribosome prevents aggregation by providing a competing hydrophobic environment and may be critical for attaining the functional conformation necessary for chaperone activity.

  12. Bacillus odysseyi sp. nov., a round-spore-forming bacillus isolated from the Mars Odyssey spacecraft

    NASA Technical Reports Server (NTRS)

    La Duc, Myron T.; Satomi, Masataka; Venkateswaran, Kasthuri

    2004-01-01

    A round-spore-forming Bacillus species that produces an exosporium was isolated from the surface of the Mars Odyssey spacecraft. This novel species has been characterized on the basis of phenotypic traits, 16S rDNA sequence analysis and DNA-DNA hybridization. According to the results of these analyses, this strain belongs to the genus Bacillus and is a Gram-positive, aerobic, rod-shaped, endospore-forming eubacterium. Ultrathin sections of the spores showed the presence of an exosporium, spore coat, cortex and core. 16S rDNA sequence similarities between this strain, Bacillus fusiformis and Bacillus silvestris were approximately 96% and DNA-DNA reassociation values with these two bacilli were 23 and 17%, respectively. Spores of the novel species were resistant to desiccation, H2O2 and UV and gamma radiation. Of all strains tested, the spores of this strain were the most consistently resistant and survived all of the challenges posed, i.e. exposure to conditions of desiccation (100% survival), H2O2 (26% survival), UV radiation (10% survival at 660 J m(-2)) and gamma radiation (0.4% survival). The name proposed for this novel bacterium is Bacillus odysseyi sp. nov.; the type strain is 34hs-1T (=ATCC PTA-4993T=NRRL B-30641T=NBRC 100172T).

  13. Bacillus nealsonii sp. nov., isolated from a spacecraft-assembly facility, whose spores are gamma-radiation resistant

    NASA Technical Reports Server (NTRS)

    Venkateswaran, Kasthuri; Kempf, Michael; Chen, Fei; Satomi, Masataka; Nicholson, Wayne; Kern, Roger

    2003-01-01

    One of the spore-formers isolated from a spacecraft-assembly facility, belonging to the genus Bacillus, is described on the basis of phenotypic characterization, 16S rDNA sequence analysis and DNA-DNA hybridization studies. It is a Gram-positive, facultatively anaerobic, rod-shaped eubacterium that produces endospores. The spores of this novel bacterial species exhibited resistance to UV, gamma-radiation, H2O2 and desiccation. The 18S rDNA sequence analysis revealed a clear affiliation between this strain and members of the low G+C Firmicutes. High 16S rDNA sequence similarity values were found with members of the genus Bacillus and this was supported by fatty acid profiles. The 16S rDNA sequence similarity between strain FO-92T and Bacillus benzoevorans DSM 5391T was very high. However, molecular characterizations employing small-subunit 16S rDNA sequences were at the limits of resolution for the differentiation of species in this genus, but DNA-DNA hybridization data support the proposal of FO-92T as Bacillus nealsonii sp. nov. (type strain is FO-92T =ATCC BAAM-519T =DSM 15077T).

  14. Evidence for para dechlorination of polychlorobiphenyls by methanogenic bacteria

    SciTech Connect

    Ye, D.; Quensen, J.F.; Tiedje, J.M.

    1995-06-01

    When microorganisms eluted from upper Hudson River sediment were cultured without any substrate except polychlorobiphenyl (PCB)-free Hudson River sediment, methane formation was the terminal step of the anaerobic food chain. In sediments containing Aroclor 1242, addition of eubacterium-inhibiting antibiotics, which should have directly inhibited fermentative bacteria and thereby should have indirectly inhibited methanogens, resulted in no dechlorination activity or methane production. However, when substrates for methanogenic bacteria were provided along with the antibiotics (to free the methanogens from dependence on eubacteria), concomitant methane production and dechlorination of PCBs were observed. The dechlorination of Aroclor 1242 was from the para positions, a pattern distinctly different from, and more limited than, the pattern observed with untreated or pasteurized inocula. Both methane production and dechlorination in cultures amended with antibiotics plus methanogenic substrates were inhibited by 2-bromoethanesulfonic acid. These results suggest that the methanogenic bacteria are among the physiological groups capable of anaerobic dechlorination of PCBs, but that the dechlorination observed with methanogenic bacteria is less extensive than the dechlorination observed with more complex anaerobic consortia. 27 refs., 5 figs., 1 tab.

  15. Ruminococcus bromii is a keystone species for the degradation of resistant starch in the human colon

    PubMed Central

    Ze, Xiaolei; Duncan, Sylvia H; Louis, Petra; Flint, Harry J

    2012-01-01

    The release of energy from particulate substrates such as dietary fiber and resistant starch (RS) in the human colon may depend on the presence of specialist primary degraders (or ‘keystone species') within the microbial community. We have explored the roles of four dominant amylolytic bacteria found in the human colon in the degradation and utilization of resistant starches. Eubacterium rectale and Bacteroides thetaiotaomicron showed limited ability to utilize RS2- and RS3-resistant starches by comparison with Bifidobacterium adolescentis and Ruminococcus bromii. In co-culture, however, R. bromii proved unique in stimulating RS2 and RS3 utilization by the other three bacterial species, even in a medium that does not permit growth of R. bromii itself. Having previously demonstrated low RS3 fermentation in vivo in two individuals with undetectable populations of R. bromii-related bacteria, we show here that supplementation of mixed fecal bacteria from one of these volunteers with R. bromii, but not with the other three species, greatly enhanced the extent of RS3 fermentation in vitro. This argues strongly that R. bromii has a pivotal role in fermentation of RS3 in the human large intestine, and that variation in the occurrence of this species and its close relatives may be a primary cause of variable energy recovery from this important component of the diet. This work also indicates that R. bromii possesses an exceptional ability to colonize and degrade starch particles when compared with previously studied amylolytic bacteria from the human colon. PMID:22343308

  16. Enhancement of carotenoid biosynthesis in transplastomic tomatoes by induced lycopene-to-provitamin A conversion.

    PubMed

    Apel, Wiebke; Bock, Ralph

    2009-09-01

    Carotenoids are essential pigments of the photosynthetic apparatus and an indispensable component of the human diet. In addition to being potent antioxidants, they also provide the vitamin A precursor beta-carotene. In tomato (Solanum lycopersicum) fruits, carotenoids accumulate in specialized plastids, the chromoplasts. How the carotenoid biosynthetic pathway is regulated and what limits total carotenoid accumulation in fruit chromoplasts is not well understood. Here, we have introduced the lycopene beta-cyclase genes from the eubacterium Erwinia herbicola and the higher plant daffodil (Narcissus pseudonarcissus) into the tomato plastid genome. While expression of the bacterial enzyme did not strongly alter carotenoid composition, expression of the plant enzyme efficiently converted lycopene, the major storage carotenoid of the tomato fruit, into provitamin A (beta-carotene). In green leaves of the transplastomic tomato plants, more lycopene was channeled into the beta-branch of carotenoid biosynthesis, resulting in increased accumulation of xanthophyll cycle pigments and correspondingly reduced accumulation of the alpha-branch xanthophyll lutein. In fruits, most of the lycopene was converted into beta-carotene with provitamin A levels reaching 1 mg per g dry weight. Unexpectedly, transplastomic tomatoes also showed a >50% increase in total carotenoid accumulation, indicating that lycopene beta-cyclase expression enhanced the flux through the pathway in chromoplasts. Our results provide new insights into the regulation of carotenoid biosynthesis and demonstrate the potential of plastids genome engineering for the nutritional enhancement of food crops. PMID:19587100

  17. Campylobacter concisus and exotoxin 9 levels in paediatric patients with Crohn's disease and their association with the intestinal microbiota.

    PubMed

    Kaakoush, Nadeem O; Castaño-Rodríguez, Natalia; Day, Andrew S; Lemberg, Daniel A; Leach, Steven T; Mitchell, Hazel M

    2014-01-01

    There is mounting evidence for a possible role for Campylobacter concisus in Crohn's disease (CD). However, the pathogenic potential of C. concisus remains disputed due to its presence in healthy subjects. It is documented that genetic diversity exists within this species, with some strains possessing putative virulence determinants such as exotoxin 9/DnaI that may enable them to persist intracellularly in host cells. In order to clarify this, we employed real-time PCR to determine C. concisus and exotoxin 9 levels within faecal samples of CD patients and healthy controls, and correlated these levels with abundances of microbial taxa identified in a subset of subjects. Both C. concisus and exotoxin 9 levels were found to be higher in CD patients than healthy controls, suggesting not only that CD patients had a greater abundance of C. concisus but also that their strains were likely to be more virulent. Moreover, C. concisus levels correlated with the exotoxin 9 levels in CD patients but not in healthy controls, indicating that healthy controls were colonized by non-virulent C. concisus strains. Correlations with the intestinal microbiota found C. concisus levels to correlate with Eubacterium, Subdoligranulum and Blautia, while exotoxin 9 levels correlated with Dialister, Oscillospira, Lachnospira and Prevotella. This suggests that either the composition of the intestinal microbial flora has the ability to influence levels of both virulent and non-virulent C. concisus strains, or infection with C. concisus may modulate the levels of specific bacterial taxa within the gastrointestinal tract. PMID:24105841

  18. Rumen fermentation and acetogen population changes in response to an exogenous acetogen TWA4 strain and Saccharomyces cerevisiae fermentation product*

    PubMed Central

    Yang, Chun-lei; Guan, Le-luo; Liu, Jian-xin; Wang, Jia-kun

    2015-01-01

    The presence of yeast cells could stimulate hydrogen utilization of acetogens and enhance acetogenesis. To understand the roles of acetogens in rumen fermentation, an in vitro rumen fermentation experiment was conducted with addition of acetogen strain (TWA4) and/or Saccharomyces cerevisiae fermentation product (XP). A 2×2 factorial design with two levels of TWA4 (0 or 2×107 cells/ml) and XP (0 or 2 g/L) was performed. Volatile fatty acids (VFAs) were increased (P<0.05) in XP and TWA4XP, while methane was increased only in TWA4XP (P<0.05). The increase rate of microorganisms with formyltetrahydrofolate synthetase, especially acetogens, was higher than that of methanogens under all treatments. Lachnospiraceae was predominant in all acetogen communities, but without close acetyl-CoA synthase (ACS) amino acid sequences from cultured isolates. Low-Acetitomaculum ruminis-like ACS was predominant in all acetogen communities, while four unique phylotypes in XP treatment were all amino acid identified low-Eubacterium limosum-like acetogens. It differs to XP treatment that more low-A. ruminis-like and less low-E. limosum-like sequences were identified in TWA4 and TWA4XP treatments. Enhancing acetogenesis by supplementation with an acetogen strain and/or yeast cells may be an approach to mitigate methane, by targeting proper acetogens such as uncultured low-E. limosum-like acetogens. PMID:26238546

  19. Phylogenetic Analysis of Anaerobic Psychrophilic Enrichment Cultures Obtained from a Greenland Glacier Ice Core

    PubMed Central

    Sheridan, Peter P.; Miteva, Vanya I.; Brenchley, Jean E.

    2003-01-01

    The examination of microorganisms in glacial ice cores allows the phylogenetic relationships of organisms frozen for thousands of years to be compared with those of current isolates. We developed a method for aseptically sampling a sediment-containing portion of a Greenland ice core that had remained at −9°C for over 100,000 years. Epifluorescence microscopy and flow cytometry results showed that the ice sample contained over 6 × 107 cells/ml. Anaerobic enrichment cultures inoculated with melted ice were grown and maintained at −2°C. Genomic DNA extracted from these enrichments was used for the PCR amplification of 16S rRNA genes with bacterial and archaeal primers and the preparation of clone libraries. Approximately 60 bacterial inserts were screened by restriction endonuclease analysis and grouped into 27 unique restriction fragment length polymorphism types, and 24 representative sequences were compared phylogenetically. Diverse sequences representing major phylogenetic groups including alpha, beta, and gamma Proteobacteria as well as relatives of the Thermus, Bacteroides, Eubacterium, and Clostridium groups were found. Sixteen clone sequences were closely related to those from known organisms, with four possibly representing new species. Seven sequences may reflect new genera and were most closely related to sequences obtained only by PCR amplification. One sequence was over 12% distant from its closest relative and may represent a novel order or family. These results show that phylogenetically diverse microorganisms have remained viable within the Greenland ice core for at least 100,000 years. PMID:12676695

  20. Composition, taxonomy and functional diversity of the oropharynx microbiome in individuals with schizophrenia and controls.

    PubMed

    Castro-Nallar, Eduardo; Bendall, Matthew L; Pérez-Losada, Marcos; Sabuncyan, Sarven; Severance, Emily G; Dickerson, Faith B; Schroeder, Jennifer R; Yolken, Robert H; Crandall, Keith A

    2015-01-01

    The role of the human microbiome in schizophrenia remains largely unexplored. The microbiome has been shown to alter brain development and modulate behavior and cognition in animals through gut-brain connections, and research in humans suggests that it may be a modulating factor in many disorders. This study reports findings from a shotgun metagenomic analysis of the oropharyngeal microbiome in 16 individuals with schizophrenia and 16 controls. High-level differences were evident at both the phylum and genus levels, with Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria dominating both schizophrenia patients and controls, and Ascomycota being more abundant in schizophrenia patients than controls. Controls were richer in species but less even in their distributions, i.e., dominated by fewer species, as opposed to schizophrenia patients. Lactic acid bacteria were relatively more abundant in schizophrenia, including species of Lactobacilli and Bifidobacterium, which have been shown to modulate chronic inflammation. We also found Eubacterium halii, a lactate-utilizing species. Functionally, the microbiome of schizophrenia patients was characterized by an increased number of metabolic pathways related to metabolite transport systems including siderophores, glutamate, and vitamin B12. In contrast, carbohydrate and lipid pathways and energy metabolism were abundant in controls. These findings suggest that the oropharyngeal microbiome in individuals with schizophrenia is significantly different compared to controls, and that particular microbial species and metabolic pathways differentiate both groups. Confirmation of these findings in larger and more diverse samples, e.g., gut microbiome, will contribute to elucidating potential links between schizophrenia and the human microbiota. PMID:26336637

  1. Crystal structures of a group II intron maturase reveal a missing link in spliceosome evolution.

    PubMed

    Zhao, Chen; Pyle, Anna Marie

    2016-06-01

    Group II introns are self-splicing ribozymes that are essential in many organisms, and they have been hypothesized to share a common evolutionary ancestor with the spliceosome. Although structural similarity of RNA components supports this connection, it is of interest to determine whether associated protein factors also share an evolutionary heritage. Here we present the crystal structures of reverse transcriptase (RT) domains from two group II intron-encoded proteins (maturases) from Roseburia intestinalis and Eubacterium rectale, obtained at 1.2-Å and 2.1-Å resolution, respectively. These domains are more similar in architecture to the spliceosomal Prp8 RT-like domain than to any other RTs, and they share substantial similarity with flaviviral RNA polymerases. The RT domain itself is sufficient for binding intron RNA with high affinity and specificity, and it is contained within an active RT enzyme. These studies provide a foundation for understanding structure-function relationships within group II intron-maturase complexes. PMID:27136328

  2. Shedding Light on the Microbial Community of the Macropod Foregut Using 454-Amplicon Pyrosequencing

    PubMed Central

    Gulino, Lisa-Maree; Ouwerkerk, Diane; Kang, Alicia Y. H.; Maguire, Anita J.; Kienzle, Marco; Klieve, Athol V.

    2013-01-01

    Twenty macropods from five locations in Queensland, Australia, grazing on a variety of native pastures were surveyed and the bacterial community of the foregut was examined using 454-amplicon pyrosequencing. Specifically, the V3/V4 region of 16S rRNA gene was examined. A total of 5040 OTUs were identified in the data set (post filtering). Thirty-two OTUs were identified as ‘shared’ OTUS (i.e. present in all samples) belonging to either Firmicutes or Bacteroidetes (Clostridiales/Bacteroidales). These phyla predominated the general microbial community in all macropods. Genera represented within the shared OTUs included: unclassified Ruminococcaceae, unclassified Lachnospiraceae, unclassified Clostridiales, Peptococcus sp. Coprococcus spp., Streptococcus spp., Blautia sp., Ruminoccocus sp., Eubacterium sp., Dorea sp., Oscillospira sp. and Butyrivibrio sp. The composition of the bacterial community of the foregut samples of each the host species (Macropus rufus, Macropus giganteus and Macropus robustus) was significantly different allowing differentiation between the host species based on alpha and beta diversity measures. Specifically, eleven dominant OTUs that separated the three host species were identified and classified as: unclassified Ruminococcaceae, unclassified Bacteroidales, Prevotella spp. and a Syntrophococcus sucromutans. Putative reductive acetogens and fibrolytic bacteria were also identified in samples. Future work will investigate the presence and role of fibrolytics and acetogens in these ecosystems. Ideally, the isolation and characterization of these organisms will be used for enhanced feed efficiency in cattle, methane mitigation and potentially for other industries such as the biofuel industry. PMID:23626688

  3. Gut microbiome diversity in acute infective and chronic inflammatory gastrointestinal diseases in North India.

    PubMed

    Kedia, Saurabh; Rampal, Ritika; Paul, Jaishree; Ahuja, Vineet

    2016-07-01

    The disease profile in the Indian population provides a unique opportunity for studying the host microbiome interaction in both infectious (amebiasis) and autoimmune diseases like inflammatory bowel disease (IBD) from a similar environment and genetic background. Analysis of fecal samples from untreated amebic liver abscess (ALA) patients, Entamoeba histolytica (Eh)-negative and -positive asymptomatic individuals, and pus samples from naive ALA patients revealed a significant reduction in Lactobacillus in asymptomatic individuals (Eh +ve) and ALA patients. Two anaerobic genera, namely Bacteroides and Peptostreptococcus, were detected in naive ALA pus samples. Analysis of fecal samples from amoebic colitis patients showed a significant decline in population of Bacteroides, Clostridium coccoides and leptum subgroup, Lactobacillus, Campylobacter, and Eubacterium, whereas a significant increase in Bifidobacterium was observed. Mucosa-associated bacterial flora analysis from IBD patients and healthy controls revealed a significant difference in concentration of bacteria among predominating and subdominating genera between ulcerative colitis (UC), Crohn's disease (CD) patients, and controls. In contrast to the mucosal studies, we found a significant increase in lactobacilli population in fecal samples of active UC patients. Another study revealed a significant decrease of Clostridium coccoides and leptum clusters in fecal samples of active UC patients along with decreased concentrations of fecal SCFAs, especially of n-butyrate, iso-butyrate, and acetate. We therefore found similar perturbations in gut microbiome in both infectious and autoimmune diseases, indicating inflammation to be the major driver for changes in gut microbiome. PMID:26994772

  4. The Arthromitus stage of Bacillus cereus: intestinal symbionts of animals

    NASA Technical Reports Server (NTRS)

    Margulis, L.; Jorgensen, J. Z.; Dolan, S.; Kolchinsky, R.; Rainey, F. A.; Lo, S. C.

    1998-01-01

    In the guts of more than 25 species of arthropods we observed filaments containing refractile inclusions previously discovered and named "Arthromitus" in 1849 by Joseph Leidy [Leidy, J. (1849) Proc. Acad. Nat. Sci. Philadelphia 4, 225-233]. We cultivated these microbes from boiled intestines of 10 different species of surface-cleaned soil insects and isopod crustaceans. Literature review and these observations lead us to conclude that Arthromitus are spore-forming, variably motile, cultivable bacilli. As long rod-shaped bacteria, they lose their flagella, attach by fibers or fuzz to the intestinal epithelium, grow filamentously, and sporulate from their distal ends. When these organisms are incubated in culture, their life history stages are accelerated by light and inhibited by anoxia. Characterization of new Arthromitus isolates from digestive tracts of common sow bugs (Porcellio scaber), roaches (Gromphodorhina portentosa, Blaberus giganteus) and termites (Cryptotermes brevis, Kalotermes flavicollis) identifies these flagellated, spore-forming symbionts as a Bacillus sp. Complete sequencing of the 16S rRNA gene from four isolates (two sow bug, one hissing roach, one death's head roach) confirms these as the low-G+C Gram-positive eubacterium Bacillus cereus. We suggest that B. cereus and its close relatives, easily isolated from soil and grown on nutrient agar, enjoy filamentous growth in moist nutrient-rich intestines of healthy arthropods and similar habitats.

  5. A role for tungsten in the biology of Campylobacter jejuni: tungstate stimulates formate dehydrogenase activity and is transported via an ultra-high affinity ABC system distinct from the molybdate transporter.

    PubMed

    Smart, Jonathan P; Cliff, Matthew J; Kelly, David J

    2009-11-01

    The food-borne pathogen Campylobacter jejuni possesses no known tungstoenzymes, yet encodes two ABC transporters (Cj0300-0303 and Cj1538-1540) homologous to bacterial molybdate (ModABC) uptake systems and the tungstate transporter (TupABC) of Eubacterium acidaminophilum respectively. The actual substrates and physiological role of these transporters were investigated. Tryptophan fluorescence spectroscopy and isothermal titration calorimetry of the purified periplasmic binding proteins of each system revealed that while Cj0303 is unable to discriminate between molybdate and tungstate (K(D) values for both ligands of 4-8 nM), Cj1540 binds tungstate with a K(D) of 1.0 +/- 0.2 pM; 50 000-fold more tightly than molybdate. Induction-coupled plasma mass spectroscopy of single and double mutants showed that this large difference in affinity is reflected in a lower cellular tungsten content in a cj1540 (tupA) mutant compared with a cj0303c (modA) mutant. Surprisingly, formate dehydrogenase (FDH) activity was decreased approximately 50% in the tupA strain, and supplementation of the growth medium with tungstate significantly increased FDH activity in the wild type, while inhibiting known molybdoenzymes. Our data suggest that C. jejuni possesses a specific, ultra-high affinity tungstate transporter that supplies tungsten for incorporation into FDH. Furthermore, possession of two MoeA paralogues may explain the formation of both molybdopterin and tungstopterin in this bacterium. PMID:19818021

  6. Differential Induction of Colitis and Gastritis in HLA-B27 Transgenic Rats Selectively Colonized with Bacteroides vulgatus or Escherichia coli

    PubMed Central

    Rath, Heiko C.; Wilson, Kenneth H.; Sartor, R. Balfour

    1999-01-01

    Resident bacteria play an important role in initiating and perpetuating gastrointestinal inflammation. We previously demonstrated that six commensal bacteria including Bacteroides vulgatus caused more aggressive colitis and gastritis in HLA-B27 transgenic rats than did the other five bacteria without B. vulgatus. This study compared the degree of gastrointestinal inflammation in gnotobiotic HLA-B27 transgenic rats monoassociated with either B. vulgatus or Escherichia coli. Gnotobiotic transgenic rats raised in Trexler isolators were selectively colonized with either B. vulgatus or E. coli. Control rats were either germfree or colonized with six common commensal bacteria (Streptococcus faecium, E. coli, Streptococcus avium, Eubacterium contortum, Peptostreptococcus productus, and B. vulgatus [DESEP-B]). After 1 month, all the rats were killed and tissues were prepared for histologic and biochemical evaluation. Colitis induced by B. vulgatus monoassociation was almost equal to that in DESEP-B-colonized rats and was significantly more severe than E. coli-induced colitis, which was absent by histological testing and mild by colonic myeloperoxidase and interleukin-1β concentration determinations. However, gastritis was detectable only in DESEP-B-associated rats. These studies suggest that not all resident bacteria have equal proinflammatory capabilities, since B. vulgatus alone is more active than E. coli alone in inducing colitis, and that colitis and gastritis result from different luminal bacterial stimuli. PMID:10338507

  7. Assessment of Fecal Microflora Changes in Pigs Supplemented with Herbal Residue and Prebiotic

    PubMed Central

    Samanta, Ashis Kumar; Jayaram, C.; Jayapal, N.; Sondhi, N.; Kolte, A. P.; Senani, S.; Sridhar, M.; Dhali, A.

    2015-01-01

    Antibiotic usage in animals as a growth promoter is considered as public health issue due to its negative impact on consumer health and environment. The present study aimed to evaluate effectiveness of herbal residue (ginger, Zingiber officinale, dried rhizome powder) and prebiotic (inulin) as an alternative to antibiotics by comparing fecal microflora composition using terminal restriction fragment length polymorphism. The grower pigs were offered feed containing antibiotic (tetracycline), ginger and inulin separately and un-supplemented group served as control. The study revealed significant changes in the microbial abundance based on operational taxonomic units (OTUs) among the groups. Presumptive identification of organisms was established based on the fragment length of OTUs generated with three restriction enzymes (MspI, Sau3AI and BsuRI). The abundance of OTUs representing Bacteroides intestinalis, Eubacterium oxidoreducens, Selonomonas sp., Methylobacterium sp. and Denitrobacter sp. was found significantly greater in inulin supplemented pigs. Similarly, the abundance of OTUs representing Bacteroides intestinalis, Selonomonas sp., and Phascolarcobacterium faecium was found significantly greater in ginger supplemented pigs. In contrast, the abundance of OTUs representing pathogenic microorganisms Atopostipes suicloacalis and Bartonella quintana str. Toulouse was significantly reduced in ginger and inulin supplemented pigs. The OTUs were found to be clustered under two major phylotypes; ginger-inulin and control-tetracycline. Additionally, the abundance of OTUs was similar in ginger and inulin supplemented pigs. The results suggest the potential of ginger and prebioticsto replace antibiotics in the diet of grower pig. PMID:26176779

  8. [Strict anaerobic bacteria: comparative study of various beta-lactam antibiotics in combination with tazobactam or sulbactam].

    PubMed

    Dubreuil, L; Sedallian, A

    1991-05-01

    The minimal inhibitory concentrations of piperacillin (PIP) or cefotaxime (CTX) alone or in combination with tazobactam (TAZ) were determined against 168 anaerobes. All the strains were inhibited by PIP + TAZ, but certain strains resistant to CTX + TAZ were found among B. fragilis, Eubacterium and Peptostreptococcus. The second investigations included 30 strains of Bacteroides fragilis. Concentrations of 2, 4 and 8 mg/l of TAZ and sulbactam (SUL) were combined with piperacillin or cefotaxime. The two beta-lactamase-inhibitors had similar activities when used at 2 or 4 mg/l, but at 8 mg/l TAZ was more active than SUL. All B. fragilis strains were inhibited by PIP + TAZ or PIP + SUL, whereas resistance was observed with CTX + SUL or CTX + TAZ. On the same strains the activities of 6 beta-lactams (PIP, mezlocillin, ticarcillin (TIC), CTX, ceftriaxone and ceftazidime) were determined in combination with either SUL 4 mg/l or TAZ 8 mg/l. Only PIP or TIC + SUL or TAZ were able to inhibit at least 90% of tested strains. No resistance could be detected with PIP + TAZ combination. As conclusion, the two inhibitors when combined with PIP or TIC offered greater activity against both Gram positive or negative anaerobes and PIP + TAZ remained the more potent combination. PMID:1652729

  9. Increased in vitro activity of ceftriaxone by addition of tazobactam against clinical isolates of anaerobes.

    PubMed

    Aldridge, K E; Morice, N; Schiro, D D

    1994-08-01

    A total of 461 clinical strains of anaerobes were tested using a broth microdilution test to determine the activity of the combination of ceftriaxone and tazobactam and other antimicrobials against these isolates. Ceftriaxone was combined with tazobactam in ratios of 1:1, 2:1, 4:1, and 8:1 and twofold dilutions of ceftriaxone in constant concentrations to tazobactam of 2, 4, 8, 16, and 32 micrograms/ml. Against beta-lactamase-producing strains of the Bacteroides fragilis group, B. capillosus, and Prevotella species all combinations of ceftriaxone and tazobactam showed enhanced in vitro activity and were eight- to 2048-fold more active than ceftriaxone alone. By comparison ceftriaxone and tazobactam showed superior or equal activity to ampicillin and sulbactam, piperacillin and tazobactam, amoxicillin and clavulanate, ticarcillin and clavulanate, and metronidazole against these same strains. Against beta-lactamase nonproducing strains of Porphyromonas, Fusobacterium, Clostridium, Eubacterium, Peptostreptococcus, and Veillonella parvula the addition of tazobactam produced no appreciable enhanced ceftriaxone activity. Fixed concentrations of tazobactam at 2 and 4 micrograms/ml appear to be most suitable for susceptibility testing and are within the pharmacologic profile of this inhibitor. Pharmacologic and toxicity studies will be needed to define the role of ceftriaxone and tazobactam in infectious diseases. PMID:7851086

  10. Consumption of Human Milk Oligosaccharides by Gut-related Microbes

    PubMed Central

    Marcobal, Angela; Barboza, Mariana; Froehlich, John W.; Block, David E.; German, J. Bruce; Lebrilla, Carlito B.; Mills, David A.

    2010-01-01

    Human milk contains large amounts of complex oligosaccharides that putatively modulate the intestinal microbiota of breast-fed infants by acting as decoy binding sites for pathogens and as prebiotics for enrichment of beneficial bacteria. Several bifidobacterial species have been shown to grow well on human milk oligosaccharides. However, little data exists on other bacterial species. In this work we examined 16 bacterial strains belonging to 10 different genera for growth on human milk oligosaccharides. For this propose, we used a chemically-defined medium, ZMB1, which allows vigorous growth of a number gut–related microorganisms in a fashion similar to complex media. Interestingly, Bifidobacterium longum subsp. infantis, Bacteroides fragilis and Bacteroides vulgatus strains were able to metabolize milk oligosaccharides with high efficiency, while Enterococcus, Streptococcus, Veillonella, Eubacterium, Clostridium, and Escherichia coli strains grew less well or not at all. Mass spectrometry-based glycoprofiling of the oligosaccharide consumption behavior revealed a specific preference for fucosylated oligosaccharides by Bifidobacterium longum subsp. infantis and Bacteroides vulgatus. This work expands the current knowledge of human milk oligosaccharides consumption by gut microbes, revealing bacteroides as avid consumer of this substrate. These results provide insight on how human milk oligosaccharides shape the infant intestinal microbiota. PMID:20394371

  11. Comparative evaluation of supplemented peptone broth with sodium polyanetholesulfonate and trypticase soy broth with sodium amylosulfate for detection of septicemia.

    PubMed Central

    Tenney, J H; Reller, L B; Wang, W L; Cox, R L; Mirrett, S

    1982-01-01

    We compared the yield and speed of detection of clinically important microorganisms from 10,156 paired 5-ml samples of blood cultured in supplemented peptone broth (SPB) with 0.03% sodium polyanetholesulfonate (SPS) or Trypticase soy broth (TSB) with 0.5% sodium amylosulfate (SAS). The atmosphere of incubation (open venting units) and ratio of blood to broth (1:10) were the same for both samples. Only cultures with adequate blood samples (greater than or equal to 80% of stated volume) were compared statistically. Overall, SPB/SPS outperformed TSB/SAS. Bacteroidaceae and Eubacterium were found more often (P less than 0.05) and viridans streptococci were found sooner (P less than 10(-4)) in SPB/SPS than in TSB/SAS. Most importantly, staphylococci were found both more often (P less than 0.03) and sooner (P less than 10(-7)) in SPB/SPS than in TSB/SAS. In a separate experiment, SAS slowed the growth of a clinical strain of Staphylococcus aureus in TSB. Unless important advantages can be confirmed for SAS in controlled clinical trials, SAS cannot be recommended for routine use as an anticoagulant in blood culture media. PMID:6286716

  12. Mining of luxS genes from rumen microbial consortia by metagenomic and metatranscriptomic approaches.

    PubMed

    Ghali, Ines; Shinkai, Takumi; Mitsumori, Makoto

    2016-05-01

    Although rumen bacterial communities vary depending on many factors such as diet, age and physiological conditions, a core microbiota exists within the rumen. In many natural environments, some bacteria use a quorum-sensing (QS) system to regulate their physiological activities. However, very limited information is available about QS systems in rumen. To investigate the autoinducer 2 (AI-2)-mediated QS system in rumen, we detected genes (luxS) encoding the AI-2 synthase (LuxS), from three datasets embedded in metagenomics RAST server (MG-RAST) and from a metatranscriptome dataset. We collected 135 luxS genes from the metagenomic datasets, which were presumed to originate from Bacteroidetes, Firmicutes, Fusobacteria and Actinobacteria, and 34 luxS genes from the metatranscriptome dataset, which probably originated from Bacteroidetes, Firmicutes and Spirochaetes. Because the essential amino acids for LuxS activity were conserved in the LuxS homologues predicted from luxS gene sequences from both datasets, the LuxS homologues probably function in the rumen. Since the largest number of sequences of luxS genes were collected from the genera Prevotella, Ruminococcus and Eubacterium, which include many fibrolytic bacteria and constituent members of biofilm on feed particles, an AI-2-mediated QS system is likely involved in biofilm formation and fibrolytic activity in the rumen. PMID:26277986

  13. Crystal structure of a eukaryote/archaeon-like protyl-tRNA synthetase and its complex with tRNAPro(CGG).

    PubMed

    Yaremchuk, A; Cusack, S; Tukalo, M

    2000-09-01

    Prolyl-tRNA synthetase (ProRS) is a class IIa synthetase that, according to sequence analysis, occurs in different organisms with one of two quite distinct structural architectures: prokaryote-like and eukaryote/archaeon-like. The primary sequence of ProRS from the hypothermophilic eubacterium Thermus thermophilus (ProRSTT) shows that this enzyme is surprisingly eukaryote/archaeon-like. We describe its crystal structure at 2.43 angstom resolution, which reveals a feature that is unique among class II synthetases. This is an additional zinc-containing domain after the expected class IIa anticodon-binding domain and whose C-terminal extremity, which ends in an absolutely conserved tyrosine, folds back into the active site. We also present an improved structure of ProRSTT complexed with tRNAPro(CGG) at 2.85 angstom resolution. This structure represents an initial docking state of the tRNA in which the anticodon stem-loop is engaged, particularly via the tRNAPro-specific bases G35 and G36, but the 3' end does not enter the active site. Considerable structural changes in tRNA and/or synthetase, which are probably induced by small substrates, are required to achieve the conformation active for aminoacylation. PMID:10970866

  14. Heme-copper terminal oxidase using both cytochrome c and ubiquinol as electron donors.

    PubMed

    Gao, Ye; Meyer, Björn; Sokolova, Lucie; Zwicker, Klaus; Karas, Michael; Brutschy, Bernd; Peng, Guohong; Michel, Hartmut

    2012-02-28

    The cytochrome c oxidase Cox2 has been purified from native membranes of the hyperthermophilic eubacterium Aquifex aeolicus. It is a cytochrome ba(3) oxidase belonging to the family B of the heme-copper containing terminal oxidases. It consists of three subunits, subunit I (CoxA2, 63.9 kDa), subunit II (CoxB2, 16.8 kDa), and an additional subunit IIa of 5.2 kDa. Surprisingly it is able to oxidize both reduced cytochrome c and ubiquinol in a cyanide sensitive manner. Cox2 is part of a respiratory chain supercomplex. This supercomplex contains the fully assembled cytochrome bc(1) complex and Cox2. Although direct ubiquinol oxidation by Cox2 conserves less energy than ubiquinol oxidation by the cytochrome bc(1) complex followed by cytochrome c oxidation by a cytochrome c oxidase, ubiquinol oxidation by Cox2 is of advantage when all ubiquinone would be completely reduced to ubiquinol, e.g., by the sulfidequinone oxidoreductase, because the cytochrome bc(1) complex requires the presence of ubiquinone to function according to the Q-cycle mechanism. In the case that all ubiquinone has been reduced to ubiquinol its reoxidation by Cox2 will enable the cytochrome bc(1) complex to resume working. PMID:22334648

  15. Functional Dynamics of the Gut Microbiome in Elderly People during Probiotic Consumption

    PubMed Central

    Eloe-Fadrosh, Emiley A.; Brady, Arthur; Crabtree, Jonathan; Drabek, Elliott F.; Ma, Bing; Mahurkar, Anup; Ravel, Jacques; Haverkamp, Miriam; Fiorino, Anne-Maria; Botelho, Christine; Andreyeva, Irina; Hibberd, Patricia L.

    2015-01-01

    ABSTRACT A mechanistic understanding of the purported health benefits conferred by consumption of probiotic bacteria has been limited by our knowledge of the resident gut microbiota and its interaction with the host. Here, we detail the impact of a single-organism probiotic, Lactobacillus rhamnosus GG ATCC 53103 (LGG), on the structure and functional dynamics (gene expression) of the gut microbiota in a study of 12 healthy individuals, 65 to 80 years old. The analysis revealed that while the overall community composition was stable as assessed by 16S rRNA profiling, the transcriptional response of the gut microbiota was modulated by probiotic treatment. Comparison of transcriptional profiles based on taxonomic composition yielded three distinct transcriptome groups that displayed considerable differences in functional dynamics. The transcriptional profile of LGG in vivo was remarkably concordant across study subjects despite the considerable interindividual nature of the gut microbiota. However, we identified genes involved in flagellar motility, chemotaxis, and adhesion from Bifidobacterium and the dominant butyrate producers Roseburia and Eubacterium whose expression was increased during probiotic consumption, suggesting that LGG may promote interactions between key constituents of the microbiota and the host epithelium. These results provide evidence for the discrete functional effects imparted by a specific single-organism probiotic and challenge the prevailing notion that probiotics substantially modify the resident microbiota within nondiseased individuals in an appreciable fashion. PMID:25873374

  16. Models for the a subunits of the Thermus thermophilus V/A-ATPase and Saccharomyces cerevisiae V-ATPase enzymes by cryo-EM and evolutionary covariance.

    PubMed

    Schep, Daniel G; Zhao, Jianhua; Rubinstein, John L

    2016-03-22

    Rotary ATPases couple ATP synthesis or hydrolysis to proton translocation across a membrane. However, understanding proton translocation has been hampered by a lack of structural information for the membrane-embedded a subunit. The V/A-ATPase from the eubacteriumThermus thermophilusis similar in structure to the eukaryotic V-ATPase but has a simpler subunit composition and functions in vivo to synthesize ATP rather than pump protons. We determined theT. thermophilusV/A-ATPase structure by cryo-EM at 6.4 Å resolution. Evolutionary covariance analysis allowed tracing of the a subunit sequence within the map, providing a complete model of the rotary ATPase. Comparing the membrane-embedded regions of theT. thermophilusV/A-ATPase and eukaryotic V-ATPase fromSaccharomyces cerevisiaeallowed identification of the α-helices that belong to the a subunit and revealed the existence of previously unknown subunits in the eukaryotic enzyme. Subsequent evolutionary covariance analysis enabled construction of a model of the a subunit in theS. cerevisaeV-ATPase that explains numerous biochemical studies of that enzyme. Comparing the two a subunit structures determined here with a structure of the distantly related a subunit from the bovine F-type ATP synthase revealed a conserved pattern of residues, suggesting a common mechanism for proton transport in all rotary ATPases. PMID:26951669

  17. Impact of dietary resistant starch type 4 on human gut microbiota and immunometabolic functions.

    PubMed

    Upadhyaya, Bijaya; McCormack, Lacey; Fardin-Kia, Ali Reza; Juenemann, Robert; Nichenametla, Sailendra; Clapper, Jeffrey; Specker, Bonny; Dey, Moul

    2016-01-01

    Dietary modulation of the gut microbiota impacts human health. Here we investigated the hitherto unknown effects of resistant starch type 4 (RS4) enriched diet on gut microbiota composition and short-chain fatty acid (SCFA) concentrations in parallel with host immunometabolic functions in twenty individuals with signs of metabolic syndrome (MetS). Cholesterols, fasting glucose, glycosylated haemoglobin, and proinflammatory markers in the blood as well as waist circumference and % body fat were lower post intervention in the RS4 group compared with the control group. 16S-rRNA gene sequencing revealed a differential abundance of 71 bacterial operational taxonomic units, including the enrichment of three Bacteroides species and one each of Parabacteroides, Oscillospira, Blautia, Ruminococcus, Eubacterium, and Christensenella species in the RS4 group. Gas chromatography-mass spectrometry revealed higher faecal SCFAs, including butyrate, propionate, valerate, isovalerate, and hexanoate after RS4-intake. Bivariate analyses showed RS4-specific associations of the gut microbiota with the host metabolic functions and SCFA levels. Here we show that dietary RS4 induced changes in the gut microbiota are linked to its biological activity in individuals with signs of MetS. These findings have potential implications for dietary guidelines in metabolic health management. PMID:27356770

  18. Aminocella lysinolytica gen. nov., sp. nov., a L-lysine-degrading, strictly anaerobic bacterium in the class Clostridia isolated from a methanogenic reactor of cattle farms.

    PubMed

    Ueki, Atsuko; Shibuya, Toru; Kaku, Nobuo; Ueki, Katsuji

    2015-01-01

    A strictly anaerobic bacterial strain (WN037(T)) was isolated from a methanogenic reactor. Cells were Gram-positive rods. Strain WN037(T) was asaccharolytic. The strain fermented L-lysine in the presence of B-vitamin mixture or vitamin B12 and produced acetate and butyrate. L-arginine and casamino acids poorly supported the growth. Strain WN037(T) used neither other amino acids nor organic acids examined. The strain had C18:1 ω7c, C16:0 and C18:1 ω7c DMA as the predominant cellular fatty acids. The genomic DNA G + C content was 44.2 mol %. Phylogenetic analysis based on the 16S rRNA gene sequence placed strain WN037(T) in the family Eubacteriaceae in the class Clostridia. The closest relative was Eubacterium pyruvativorans (sequence similarity, 92.8 %). Based on the comprehensive analyses, the novel genus and species, Aminocella lysinolytica gen. nov., sp. nov. was proposed to accommodate the strain. The type strain is WN037(T) (= JCM 19863(T) = DSM 28287(T)). PMID:25449329

  19. Anaerobic biosynthesis of the lower ligand of vitamin B12

    PubMed Central

    Hazra, Amrita B.; Han, Andrew W.; Mehta, Angad P.; Mok, Kenny C.; Osadchiy, Vadim; Begley, Tadhg P.; Taga, Michiko E.

    2015-01-01

    Vitamin B12 (cobalamin) is required by humans and other organisms for diverse metabolic processes, although only a subset of prokaryotes is capable of synthesizing B12 and other cobamide cofactors. The complete aerobic and anaerobic pathways for the de novo biosynthesis of B12 are known, with the exception of the steps leading to the anaerobic biosynthesis of the lower ligand, 5,6-dimethylbenzimidazole (DMB). Here, we report the identification and characterization of the complete pathway for anaerobic DMB biosynthesis. This pathway, identified in the obligate anaerobic bacterium Eubacterium limosum, is composed of five previously uncharacterized genes, bzaABCDE, that together direct DMB production when expressed in anaerobically cultured Escherichia coli. Expression of different combinations of the bza genes revealed that 5-hydroxybenzimidazole, 5-methoxybenzimidazole, and 5-methoxy-6-methylbenzimidazole, all of which are lower ligands of cobamides produced by other organisms, are intermediates in the pathway. The bza gene content of several bacterial and archaeal genomes is consistent with experimentally determined structures of the benzimidazoles produced by these organisms, indicating that these genes can be used to predict cobamide structure. The identification of the bza genes thus represents the last remaining unknown component of the biosynthetic pathway for not only B12 itself, but also for three other cobamide lower ligands whose biosynthesis was previously unknown. Given the importance of cobamides in environmental, industrial, and human-associated microbial metabolism, the ability to predict cobamide structure may lead to an improved ability to understand and manipulate microbial metabolism. PMID:26246619

  20. Establishment of Intestinal Microbiota during Early Life: a Longitudinal, Explorative Study of a Large Cohort of Danish Infants

    PubMed Central

    Bergström, Anders; Skov, Thomas Hjort; Bahl, Martin Iain; Roager, Henrik Munch; Christensen, Line Brinch; Ejlerskov, Katrine Tschentscher; Mølgaard, Christian; Michaelsen, Kim F.

    2014-01-01

    Fecal samples were obtained from a cohort of 330 healthy Danish infants at 9, 18, and 36 months after birth, enabling characterization of interbacterial relationships by use of quantitative PCR targeting 31 selected bacterial 16S rRNA gene targets representing different phylogenetic levels. Nutritional parameters and measures of growth and body composition were determined and investigated in relation to the observed development in microbiota composition. We found that significant changes in the gut microbiota occurred, particularly from age 9 to 18 months, when cessation of breastfeeding and introduction of a complementary feeding induce replacement of a microbiota characterized by lactobacilli, bifidobacteria, and Enterobacteriaceae with a microbiota dominated by Clostridium spp. and Bacteroides spp. Classification of samples by a proxy enterotype based on the relative levels of Bacteroides spp. and Prevotella spp. showed that enterotype establishment occurs between 9 and 36 months. Thirty percent of the individuals shifted enterotype between 18 and 36 months. The composition of the microbiota was most pronouncedly influenced by the time of cessation of breastfeeding. From 9 to 18 months, a positive correlation was observed between the increase in body mass index and the increase of the short-chain-fatty-acid-producing clostridia, the Clostridum leptum group, and Eubacterium hallii. Considering previously established positive associations between rapid infant weight gain, early breastfeeding discontinuation, and later-life obesity, the corresponding microbial findings seen here warrant attention. PMID:24584251

  1. Decoding the genomic tree of life

    PubMed Central

    Simonson, Anne B.; Servin, Jacqueline A.; Skophammer, Ryan G.; Herbold, Craig W.; Rivera, Maria C.; Lake, James A.

    2005-01-01

    Genomes hold within them the record of the evolution of life on Earth. But genome fusions and horizontal gene transfer (HGT) seem to have obscured sufficiently the gene sequence record such that it is difficult to reconstruct the phylogenetic tree of life. HGT among prokaryotes is not random, however. Some genes (informational genes) are more difficult to transfer than others (operational genes). Furthermore, environmental, metabolic, and genetic differences among organisms restrict HGT, so that prokaryotes preferentially share genes with other prokaryotes having properties in common, including genome size, genome G+C composition, carbon utilization, oxygen utilization/sensitivity, and temperature optima, further complicating attempts to reconstruct the tree of life. A new method of phylogenetic reconstruction based on gene presence and absence, called conditioned reconstruction, has improved our prospects for reconstructing prokaryotic evolution. It is also able to detect past genome fusions, such as the fusion that appears to have created the first eukaryote. This genome fusion between a deep branching eubacterium, possibly an ancestor of the cyanobacterium and a proteobacterium, with an archaeal eocyte (crenarchaea), appears to be the result of an early symbiosis. Given new tools and new genes from relevant organisms, it should soon be possible to test current and future fusion theories for the origin of eukaryotes and to discover the general outlines of the prokaryotic tree of life. PMID:15851667

  2. Gut microbial metabolites of polyunsaturated fatty acids correlate with specific fecal bacteria and serum markers of metabolic syndrome in obese women.

    PubMed

    Druart, Céline; Dewulf, Evelyne M; Cani, Patrice D; Neyrinck, Audrey M; Thissen, Jean-Paul; Delzenne, Nathalie M

    2014-04-01

    The aim of this human study was to assess the influence of prebiotic-induced gut microbiota modulation on PUFA-derived bacterial metabolites production. Therefore, we analyzed the circulating fatty acid profile including CLA/CLnA in obese women treated during 3 months with inulin-type fructan prebiotics. In these patients, we had already determined gut microbiota composition by phylogenetic microarray and qPCR analysis of 16S rDNA. Some PUFA-derived bacterial metabolites were detected in the serum of obese patients. Despite the prebiotic-induced modulation of gut microbiota, including changes in CLA/CLnA-producing bacteria, the treatment did not impact significantly on the circulating level of these metabolites. However, some PUFA-derived bacterial metabolites were positively correlated with specific fecal bacteria (Bifidobacterium spp., Eubacterium ventriosum and Lactobacillus spp.) and inversely correlated with serum cholesterol (total, LDL, HDL). These correlations suggest a potential beneficial effect of some of these metabolites but this remains to be confirmed by further investigation. PMID:24473752

  3. Assessment of Fecal Microflora Changes in Pigs Supplemented with Herbal Residue and Prebiotic.

    PubMed

    Samanta, Ashis Kumar; Jayaram, C; Jayapal, N; Sondhi, N; Kolte, A P; Senani, S; Sridhar, M; Dhali, A

    2015-01-01

    Antibiotic usage in animals as a growth promoter is considered as public health issue due to its negative impact on consumer health and environment. The present study aimed to evaluate effectiveness of herbal residue (ginger, Zingiber officinale, dried rhizome powder) and prebiotic (inulin) as an alternative to antibiotics by comparing fecal microflora composition using terminal restriction fragment length polymorphism. The grower pigs were offered feed containing antibiotic (tetracycline), ginger and inulin separately and un-supplemented group served as control. The study revealed significant changes in the microbial abundance based on operational taxonomic units (OTUs) among the groups. Presumptive identification of organisms was established based on the fragment length of OTUs generated with three restriction enzymes (MspI, Sau3AI and BsuRI). The abundance of OTUs representing Bacteroides intestinalis, Eubacterium oxidoreducens, Selonomonas sp., Methylobacterium sp. and Denitrobacter sp. was found significantly greater in inulin supplemented pigs. Similarly, the abundance of OTUs representing Bacteroides intestinalis, Selonomonas sp., and Phascolarcobacterium faecium was found significantly greater in ginger supplemented pigs. In contrast, the abundance of OTUs representing pathogenic microorganisms Atopostipes suicloacalis and Bartonella quintana str. Toulouse was significantly reduced in ginger and inulin supplemented pigs. The OTUs were found to be clustered under two major phylotypes; ginger-inulin and control-tetracycline. Additionally, the abundance of OTUs was similar in ginger and inulin supplemented pigs. The results suggest the potential of ginger and prebioticsto replace antibiotics in the diet of grower pig. PMID:26176779

  4. Pierisins and CARP-1: ADP-ribosylation of DNA by ARTCs in butterflies and shellfish.

    PubMed

    Nakano, Tsuyoshi; Takahashi-Nakaguchi, Azusa; Yamamoto, Masafumi; Watanabe, Masahiko

    2015-01-01

    The cabbage butterfly, Pieris rapae, and related species possess a previously unknown ADP-ribosylating toxin, guanine specific ADP-ribosyltransferase. This enzyme toxin, known as pierisin, consists of enzymatic N-terminal domain and receptor-binding C-terminal domain, or typical AB-toxin structure. Pierisin efficiently transfers an ADP-ribosyl moiety to the N(2) position of the guanine base of dsDNA. Receptors for pierisin are suggested to be the neutral glycosphingolipids, globotriaosylceramide (Gb3), and globotetraosylceramide (Gb4). This DNA-modifying toxin exhibits strong cytotoxicity and induces apoptosis in various human cell lines, which can be blocked by Bcl-2. Pierisin also produces detrimental effects on the eggs and larvae of the non-habitual parasitoids. In contrast, a natural parasitoid of the cabbage butterfly, Cotesia glomerata, was resistant to this toxin. The physiological role of pierisin in the butterfly is suggested to be a defense factor against parasitization by wasps. Other type of DNA ADP-ribosyltransferase is present in certain kinds of edible clams. For example, the CARP-1 protein found in Meretrix lamarckii consists of an enzymatic domain without a possible receptor-binding domain. Pierisin and CARP-1 are almost fully non-homologous at the amino acid sequence level, but other ADP-ribosyltransferases homologous to pierisin are present in different biological species such as eubacterium Streptomyces. Possible diverse physiological roles of the DNA ADP-ribosyltransferases are discussed. PMID:25033755

  5. Synbiotic Lactobacillus acidophilus NCFM and cellobiose does not affect human gut bacterial diversity but increases abundance of lactobacilli, bifidobacteria and branched-chain fatty acids: a randomized, double-blinded cross-over trial.

    PubMed

    van Zanten, Gabriella C; Krych, Lukasz; Röytiö, Henna; Forssten, Sofia; Lahtinen, Sampo J; Abu Al-Soud, Waleed; Sørensen, Søren; Svensson, Birte; Jespersen, Lene; Jakobsen, Mogens

    2014-10-01

    Probiotics, prebiotics, and combinations thereof, that is synbiotics, have been reported to modulate gut microbiota of humans. In this study, effects of a novel synbiotic on the composition and metabolic activity of human gut microbiota were investigated. Healthy volunteers (n = 18) were enrolled in a double-blinded, randomized, and placebo-controlled cross-over study and received synbiotic [Lactobacillus acidophilus NCFM (10(9) CFU) and cellobiose (5 g)] or placebo daily for 3 weeks. Fecal samples were collected and lactobacilli numbers were quantified by qPCR. Furthermore, 454 tag-encoded amplicon pyrosequencing was used to monitor the effect of synbiotic on the composition of the microbiota. The synbiotic increased levels of Lactobacillus spp. and relative abundances of the genera Bifidobacterium, Collinsella, and Eubacterium while the genus Dialister was decreased (P < 0.05). No other effects were found on microbiota composition. Remarkably, however, the synbiotic increased concentrations of branched-chain fatty acids, measured by gas chromatography, while short-chain fatty acids were not affected. PMID:25098489

  6. Review on microbiota and effectiveness of probiotics use in older

    PubMed Central

    Rondanelli, Mariangela; Giacosa, Attilio; Faliva, Milena Anna; Perna, Simone; Allieri, Francesca; Castellazzi, Anna Maria

    2015-01-01

    The aim of the present systematic review is to summarize the existing knowledge about the human microbiota in the elderly and the effects of probiotics in elderly population. The elderly subjects, compared to adult population, show a reduction in the diversity of the microbiota, characterized by a large interindividual variability, with lower numbers of Firmicutes, Bifidobacteria, Clostridium cluster XIV, Faecalibacterium Prausnitzii, Blautia coccoides-Eubacterium rectal and higher presence of Enterobacteriaceae and Bacteroidetes. These differences of the intestinal microbiota of the elderly may not necessarily be caused by aging, but they could be associated with the decline of the general state of health with malnutrition and with increased need for medication, such as antibiotics and nonsteroidal anti-inflammatory drugs, situations that occur frequently in the elderly. Differences have been demonstrated in the composition of the microbiota between healthy elderly subjects and hospitalized or institutionalized elderly subjects. These findings which further indicates that the living conditions, health status, nutrition and drugs have a significant effect on the composition of the microbiota. According to the available knowledge, the use of probiotics is safe and could represent an useful intervention to prevent or treat antibiotic-associated diarrhea, in addition to reducing the severity of symptoms, other than to help the management of constipation. PMID:25685762

  7. Growth requirements of hyperthermophilic sulfur-dependent heterotrophic archaea isolated from a shallow submarine geothermal system with reference to their essential amino acids.

    PubMed Central

    Hoaki, T; Nishijima, M; Kato, M; Adachi, K; Mizobuchi, S; Hanzawa, N; Maruyama, T

    1994-01-01

    Three hyperthermophilic sulfur-dependent heterotrophs were isolated from a shallow submarine hydrothermal system at an inlet of Kodakara-jima island, Kagoshima, Japan. The isolates grew at 60 to 97 degrees C, with the optimum temperatures at 85 to 90 degrees C. Sensitivity to rifampin and the existence of ether lipids indicated that the isolates are hyperthermophilic archaea. Partial sequencing of the genes coding for 16S rRNA showed that the three isolates are closely related to the genus Thermococcus. They grew on proteinaceous mixtures, such as yeast extract, Casamino Acids, and purified proteins (e.g., casein and gelatin), but not on carbohydrates or organic acids as sole carbon and energy sources. Nine amino acids were essential for growth of isolate KS-1 (Thr, Leu, Ile, Val, Met, Phe, His, Tyr, and Arg). Isolate KS-2 required Lys in addition to the nine amino acids, and KS-8 required Lys instead of Tyr. In comparative studies, it was shown that Thermococcus celer DSM 2476 required 10 amino acids (Thr, Leu, Ile, Val, Met, Phe, Tyr, Trp, Lys, and Arg) while Pyrococcus furiosus DSM 3638 required only Ile and Val. The hyperthermophilic fermentative eubacterium Thermotoga neapolitana DSM 4359 did not require any amino acids for growth. Images PMID:8085828

  8. Subnanometer resolution cryo-EM structure of a nucleotide free heterodimeric ABC exporter

    PubMed Central

    Kim, JungMin; Wu, Shenping; Tomasiak, Thomas; Mergel, Claudia; Winter, Michael B.; Stiller, Sebastian B.; Robles-Colmanares, Yaneth; Stroud, Robert M.; Tampé, Robert; Craik, Charles S.; Cheng, Yifan

    2015-01-01

    ATP-binding cassette (ABC) transporters translocate substrates across cell membranes, using energy harnessed from ATP binding and hydrolysis at their nucleotide binding domains (NBDs)1,2. ABC exporters are present in both prokaryotes and eukaryotes with examples implicated in multidrug resistance of pathogens and cancer cells, as well as in many human diseases3,4. TmrAB is a heterodimeric ABC exporter from the thermophilic Gram-negative eubacterium Thermus thermophilus homologous to various multidrug transporters and containing one degenerate site with a non-catalytic residue next to the Walker B motif5. Here we report a subnanometer resolution structure of detergent-solubilized TmrAB in a nucleotide-free, inward-facing conformation by single particle electron cryomicroscopy (cryo-EM). The reconstructions clearly resolved characteristic features of ABC transporters, including helices in the transmembrane domain (TMD) and NBDs. A cavity in the TMD is accessible laterally from the cytoplasmic side of the membrane as well as from the cytoplasm, indicating that the transporter lies in an inward-facing open conformation. The two NBDs remain in contact via their C-terminal helices. Furthermore, comparison between our structure and the crystal structures of other ABC transporters suggests a possible trajectory of conformational changes that involves a sliding and rotating motion between the two NBDs during the transition from the inward facing to outward facing conformations. PMID:25363761

  9. Cultivation of shear stress sensitive microorganisms in disposable bag reactor systems.

    PubMed

    Jonczyk, Patrick; Takenberg, Meike; Hartwig, Steffen; Beutel, Sascha; Berger, Ralf G; Scheper, Thomas

    2013-09-20

    Technical scale (≥5l) cultivations of shear stress sensitive microorganisms are often difficult to perform, as common bioreactors are usually designed to maximize the oxygen input into the culture medium. This is achieved by mechanical stirrers, causing high shear stress. Examples for shear stress sensitive microorganisms, for which no specific cultivation systems exist, are many anaerobic bacteria and fungi, such as basidiomycetes. In this work a disposable bag bioreactor developed for cultivation of mammalian cells was investigated to evaluate its potential to cultivate shear stress sensitive anaerobic Eubacterium ramulus and shear stress sensitive basidiomycetes Flammulina velutipes and Pleurotus sapidus. All cultivations were compared with conventional stainless steel stirred tank reactors (STR) cultivations. Good growth of all investigated microorganisms cultivated in the bag reactor was found. E. ramulus showed growth rates of μ=0.56 h⁻¹ (bag) and μ=0.53 h⁻¹ (STR). Differences concerning morphology, enzymatic activities and growth in fungal cultivations were observed. In the bag reactor growth in form of small, independent pellets was observed while STR cultivations showed intense aggregation. F. velutipes reached higher biomass concentrations (21.2 g l⁻¹ DCW vs. 16.8 g l⁻¹ DCW) and up to 2-fold higher peptidolytic activities in comparison to cell cultivation in stirred tank reactors. PMID:23892193

  10. Effects of dietary fibre source on microbiota composition in the large intestine of suckling piglets.

    PubMed

    Zhang, Lingli; Mu, Chunlong; He, Xiangyu; Su, Yong; Mao, Shengyong; Zhang, Jing; Smidt, Hauke; Zhu, Weiyun

    2016-07-01

    This study aimed to investigate the effects of dietary fibre sources on the gut microbiota in suckling piglets, and to test the hypothesis that a moderate increase of dietary fibre may affect the gut microbiota during the suckling period. Suckling piglets were fed different fibre-containing diets or a control diet from postnatal day 7 to 22. Digesta samples from cecum, proximal colon and distal colon were used for Pig Intestinal Tract Chip analysis. The data showed that the effects of fibre-containing diet on the gut microbiota differed in the fibre source and gut location. The alfalfa diet increased Clostridium cluster XIVb and Sporobacter termitidis in the cecum compared to the pure cellulose diet. Compared to the control diet, the alfalfa diet also increased Coprococcus eutactus in the distal colon, while the pure cellulose diet decreased Eubacterium pyruvativorans in the cecum. The pure cellulose diet increased Prevotella ruminicola compared to the wheat bran diet. Interestingly, the alfalfa group had the lowest abundance of the potential pathogen Streptococcus suis in the cecum and distal colon. These results indicated that a moderate increase in dietary fibres affected the microbial composition in suckling piglets, and that the alfalfa inclusion produced some beneficial effects on the microbial communities. PMID:27231242

  11. Co-evolution of quaternary organization and novel RNA tertiary interactions revealed in the crystal structure of a bacterial protein–RNA toxin–antitoxin system

    PubMed Central

    Rao, Feng; Short, Francesca L.; Voss, Jarrod E.; Blower, Tim R.; Orme, Anastasia L.; Whittaker, Tom E.; Luisi, Ben F.; Salmond, George P. C.

    2015-01-01

    Genes encoding toxin–antitoxin (TA) systems are near ubiquitous in bacterial genomes and they play key roles in important aspects of bacterial physiology, including genomic stability, formation of persister cells under antibiotic stress, and resistance to phage infection. The CptIN locus from Eubacterium rectale is a member of the recently-discovered Type III class of TA systems, defined by a protein toxin suppressed by direct interaction with a structured RNA antitoxin. Here, we present the crystal structure of the CptIN protein–RNA complex to 2.2 Å resolution. The structure reveals a new heterotetrameric quaternary organization for the Type III TA class, and the RNA antitoxin bears a novel structural feature of an extended A-twist motif within the pseudoknot fold. The retention of a conserved ribonuclease active site as well as traits normally associated with TA systems, such as plasmid maintenance, implicates a wider functional role for Type III TA systems. We present evidence for the co-variation of the Type III component pair, highlighting a distinctive evolutionary process in which an enzyme and its substrate co-evolve. PMID:26350213

  12. Evolution of the mitochondrial genetic system: an overview.

    PubMed

    Saccone, C; Gissi, C; Lanave, C; Larizza, A; Pesole, G; Reyes, A

    2000-12-30

    Mitochondria, semi-autonomous organelles possessing their own genetic system, are commonly accepted to descend from free-living eubacteria, namely hydrogen-producing alpha-proteobacteria. The progressive loss of genes from the primitive eubacterium to the nucleus of the eukaryotic cell is strongly justified by the Muller rachet principle, which postulates that asexual genomes, like mitochondrial ones, accumulate deleterious and sublethal mutations faster than sexual genomes, like the nucleus. According to this principle, the mitochondrial genome would be doomed to death; instead, we observe that the mitochondrial genome has a variable size and structure in the different organisms, though it contains more or less the same set of genes. This is an example of genetic conservation versus structural diversity. From an evolutionary point of view the genetic system of organelles is clearly under strong selective pressure and for its survival it needs to utilize strategies to slow down or halt the ratchet. Anyway, the mitochondrial genome changes with time, and the rate of evolution is different for both diverse regions of the mtDNA and between lineages, as demonstrated in the case of mammalian mt genomes. We report here our data on the evolution of the mitochondrial DNA in mammals which demonstrate the suitability of mtDNA as a molecular tool for evolutionary analyses. PMID:11164046

  13. Comparative in vitro fermentations of cranberry and grape seed polyphenols with colonic microbiota.

    PubMed

    Sánchez-Patán, Fernando; Barroso, Elvira; van de Wiele, Tom; Jiménez-Girón, Ana; Martín-Alvarez, Pedro J; Moreno-Arribas, M Victoria; Martínez-Cuesta, M Carmen; Peláez, Carmen; Requena, Teresa; Bartolomé, Begoña

    2015-09-15

    In this study, we have assessed the phenolic metabolism of a cranberry extract by microbiota obtained from the ascending colon and descending colon compartments of a dynamic gastrointestinal simulator (SHIME). For comparison, parallel fermentations with a grape seed extract were carried out. Extracts were used directly without previous intestinal digestion. Among the 60 phenolic compounds targeted, our results confirmed the formation of phenylacetic, phenylpropionic and benzoic acids as well as phenols such as catechol and its derivatives from the action of colonic microbiota on cranberry polyphenols. Benzoic acid (38.4μg/ml), 4-hydroxy-5-(3'-hydroxyphenyl)-valeric acid (26.2μg/ml) and phenylacetic acid (19.5μg/ml) reached the highest concentrations. Under the same conditions, microbial degradation of grape seed polyphenols took place to a lesser extent compared to cranberry polyphenols, which was consistent with the more pronounced antimicrobial effect observed for the grape seed polyphenols, particularly against Bacteroides, Prevotella and Blautia coccoides-Eubacterium rectale. PMID:25863636

  14. Heme A synthase in bacteria depends on one pair of cysteinyls for activity.

    PubMed

    Lewin, Anna; Hederstedt, Lars

    2016-02-01

    Heme A is a prosthetic group unique for cytochrome a-type respiratory oxidases in mammals, plants and many microorganisms. The poorly understood integral membrane protein heme A synthase catalyzes the synthesis of heme A from heme O. In bacteria, but not in mitochondria, this enzyme contains one or two pairs of cysteine residues that are present in predicted hydrophilic polypeptide loops on the extracytoplasmic side of the membrane. We used heme A synthase from the eubacterium Bacillus subtilis and the hyperthermophilic archeon Aeropyrum pernix to investigate the functional role of these cysteine residues. Results with B. subtilis amino acid substituted proteins indicated the pair of cysteine residues in the loop connecting transmembrane segments I and II as being essential for catalysis but not required for binding of the enzyme substrate, heme O. Experiments with isolated A. pernix and B. subtilis heme A synthase demonstrated that a disulfide bond can form between the cysteine residues in the same loop and also between loops showing close proximity of the two loops in the folded enzyme protein. Based on the findings, we propose a classification scheme for the four discrete types of heme A synthase found so far in different organisms and propose that essential cysteinyls mediate transfer of reducing equivalents required for the oxygen-dependent catalysis of heme A synthesis from heme O. PMID:26592143

  15. Effect of dietary copper sulfate, Aureo SP250, or clinoptilolite on ureolytic bacteria found in the pig large intestine.

    PubMed Central

    Varel, V H; Robinson, I M; Pond, W G

    1987-01-01

    The predominant ureolytic bacteria in the pig large intestine were determined while growing pigs were fed a basal diet or basal diet plus copper sulfate, Aureo SP250, or clinoptilolite. Fecal samples were collected from four pigs fed each diet at 3, 9, and 14 weeks and analyzed for total colony counts and percent ureolytic bacteria. Fecal urease activity, ammonia nitrogen, and identity of the ureolytic bacteria were determined at 14 weeks. Copper sulfate and Aureo SP250 reduced the number of ureolytic organisms, with a marked decrease occurring in the Streptococcus spp., which made up 74% of the ureolytic isolates from the pigs on the basal diet. Other ureolytic species detected at lower concentrations were Staphylococcus spp., Selenomonas ruminantium, Bacteroides multiacidus, and Eubacterium limosum. Copper sulfate also reduced fecal urease activity (P less than 0.10). Fecal ammonia concentrations were not different between pigs fed the various diets. These data suggest that the streptococci are the most numerous ureolytic species in the pig intestinal tract and are significantly reduced by copper sulfate and Aureo SP250; however, only copper sulfate reduced intestinal urease activity. PMID:2823707

  16. Effect of dietary copper sulfate, Aureo SP250, or clinoptilolite on ureolytic bacteria found in the pig large intestine.

    PubMed

    Varel, V H; Robinson, I M; Pond, W G

    1987-09-01

    The predominant ureolytic bacteria in the pig large intestine were determined while growing pigs were fed a basal diet or basal diet plus copper sulfate, Aureo SP250, or clinoptilolite. Fecal samples were collected from four pigs fed each diet at 3, 9, and 14 weeks and analyzed for total colony counts and percent ureolytic bacteria. Fecal urease activity, ammonia nitrogen, and identity of the ureolytic bacteria were determined at 14 weeks. Copper sulfate and Aureo SP250 reduced the number of ureolytic organisms, with a marked decrease occurring in the Streptococcus spp., which made up 74% of the ureolytic isolates from the pigs on the basal diet. Other ureolytic species detected at lower concentrations were Staphylococcus spp., Selenomonas ruminantium, Bacteroides multiacidus, and Eubacterium limosum. Copper sulfate also reduced fecal urease activity (P less than 0.10). Fecal ammonia concentrations were not different between pigs fed the various diets. These data suggest that the streptococci are the most numerous ureolytic species in the pig intestinal tract and are significantly reduced by copper sulfate and Aureo SP250; however, only copper sulfate reduced intestinal urease activity. PMID:2823707

  17. Decreased Diversity of the Oral Microbiota of Patients with Hepatitis B Virus-Induced Chronic Liver Disease: A Pilot Project

    PubMed Central

    Ling, Zongxin; Liu, Xia; Cheng, Yiwen; Jiang, Xiawei; Jiang, Haiyin; Wang, Yuezhu; Li, Lanjuan

    2015-01-01

    Increasing evidence suggests that altered gut microbiota is implicated in the pathogenesis of hepatitis B virus-induced chronic liver disease (HBV-CLD). However, the structure and composition of the oral microbiota of patients with HBV-CLD remains unclear. High-throughput pyrosequencing showed that decreased oral bacterial diversity was found in patients with HBV-CLD. The Firmicutes/Bacteroidetes ratio was increased significantly, which indicated that dysbiosis of the oral microbiota participated in the process of HBV-CLD development. However, the changing patterns of the oral microbiota in patients with HBV-induced liver cirrhosis (LC) were almost similar to patients with chronic hepatitis B (CHB). HBV infection resulted in an increase in potential H2S- and CH3SH-producing phylotypes such as Fusobacterium, Filifactor, Eubacterium, Parvimonas and Treponema, which might contribute to the increased oral malodor. These key oral-derived phylotypes might invade into the gut as opportunistic pathogens and contribute to altering the composition of the gut microbiota. This study provided important clues that dysbiosis of the oral microbiota might be involved in the development of HBV-CLD. Greater understanding of the relationships between the dysbiosis of oral microbiota and the development of HBV-CLD might facilitate the development of non-invasive differential diagnostic procedures and targeted treatments of HBV-CLD patients harbouring specific oral phylotypes. PMID:26606973

  18. Effect of prebiotics on the fecal microbiota of elderly volunteers after dietary supplementation of Bacillus coagulans GBI-30, 6086.

    PubMed

    Nyangale, Edna P; Farmer, Sean; Keller, David; Chernoff, David; Gibson, Glenn R

    2014-12-01

    In advancing age, gut populations of beneficial microbes, notably Bifidobacterium spp., show a marked decline. This contributes to an environment less capable of maintaining homoeostasis. This in vitro investigation studied the possible synergistic effects of probiotic supplementation in modulating the gut microbiota enabling prebiotic therapy to in elderly persons. Single stage batch culture anaerobic fermenters were used and inoculated with fecal microbiota obtained from volunteers after taking a 28 day treatment of Bacillus coagulans GBI-30, 6086 (GanedenBC30 (BC30)) or a placebo. The response to prebiotic supplements fructooligosaccharides (FOS) and galactooligosaccharides (GOS) in the fermenters was assessed. Bacterial enumeration was carried out using fluorescent in situ hybridisation and organic acids measured by gas chromatography. Baseline populations of Faecalibacterium prausnitzii, Clostridium lituseburense and Bacillus spp. were significantly higher in those having consumed BC30 compared to the placebo. Both prebiotics increased populations of several purportedly beneficial bacterial groups in both sets of volunteers. Samples from volunteers having ingested the BC30 also increased populations of C. lituseburense, Eubacterium rectale and F. prausnitzii more so than in persons who had consumed the placebo, this also resulted in significantly higher concentrations of butyrate, acetate and propionate. This shows that consumption of BC30 and subsequent use of prebiotics resulted in elevated populations of beneficial genres of bacteria as well as organic acid production. PMID:25219857

  19. Wheat bran promotes enrichment within the human colonic microbiota of butyrate-producing bacteria that release ferulic acid.

    PubMed

    Duncan, Sylvia H; Russell, Wendy R; Quartieri, Andrea; Rossi, Maddalena; Parkhill, Julian; Walker, Alan W; Flint, Harry J

    2016-07-01

    Cereal fibres such as wheat bran are considered to offer human health benefits via their impact on the intestinal microbiota. We show here by 16S rRNA gene-based community analysis that providing amylase-pretreated wheat bran as the sole added energy source to human intestinal microbial communities in anaerobic fermentors leads to the selective and progressive enrichment of a small number of bacterial species. In particular, OTUs corresponding to uncultured Lachnospiraceae (Firmicutes) related to Eubacterium xylanophilum and Butyrivibrio spp. were strongly enriched (by five to 160 fold) over 48 h in four independent experiments performed with different faecal inocula, while nine other Firmicutes OTUs showed > 5-fold enrichment in at least one experiment. Ferulic acid was released from the wheat bran during degradation but was rapidly converted to phenylpropionic acid derivatives via hydrogenation, demethylation and dehydroxylation to give metabolites that are detected in human faecal samples. Pure culture work using bacterial isolates related to the enriched OTUs, including several butyrate-producers, demonstrated that the strains caused substrate weight loss and released ferulic acid, but with limited further conversion. We conclude that breakdown of wheat bran involves specialist primary degraders while the conversion of released ferulic acid is likely to involve a multi-species pathway. PMID:26636660

  20. In Vitro Activities of Dalbavancin and Nine Comparator Agents against Anaerobic Gram-Positive Species and Corynebacteria

    PubMed Central

    Goldstein, Ellie J. C.; Citron, Diane M.; Merriam, C. Vreni; Warren, Yumi; Tyrrell, Kerin; Fernandez, Helen T.

    2003-01-01

    Dalbavancin is a novel semisynthetic glycopeptide with enhanced activity against gram-positive species. Its comparative in vitro activities and those of nine comparator agents, including daptomycin, vancomycin, linezolid, and quinupristin-dalfopristin, against 290 recent gram-positive clinical isolates strains, as determined by the NCCLS agar dilution method, were studied. The MICs of dalbavancin at which 90% of various isolates tested were inhibited were as follows: Actinomyces spp., 0.5 μg/ml; Clostridium clostridioforme, 8 μg/ml; C. difficile, 0.25 μg/ml; C. innocuum, 0.25 μg/ml; C. perfringens, 0.125 μg/ml; C. ramosum, 1 μg/ml; Eubacterium spp., 1 μg/ml; Lactobacillus spp., >32 μg/ml, Propionibacterium spp., 0.5 μg/ml; and Peptostreptococcus spp., 0.25 μg/ml. Dalbavancin was 1 to 3 dilutions more active than vancomycin against most strains. Dalbavancin exhibited excellent activity against gram-positive strains tested and warrants clinical evaluation. PMID:12760876