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Sample records for dato stenocereus griseus

  1. Efficient production of nonactin by Streptomyces griseus subsp. griseus.

    PubMed

    Zhan, Yulian; Zheng, Shaolun

    2016-08-01

    Here we report the production of the cyclic macrotetrolide nonactin from the fermentation culture of Streptomyces griseus subsp. griseus. Nonactin is a member of a family of naturally occurring cyclic ionophores known as the macrotetrolide antibiotics. Our fermentation procedure of Streptomyces griseus was performed at 30 °C and 200 rev·min(-1) for 5 days on a rotary shaker. Diaion HP-20 and Amberlite XAD-16 were added to the fermentation medium. Isolated yield of nonactin was up to 80 mg·L(-1) using our methodology. Nonactin is commonly known as an ammonium ionophore and also exhibits antibacterial, antiviral, and antitumor activities. It is also widely used for the preparation of ion-selective electrodes and sensors. Chemical synthesis of nonactin has been achieved by some groups; however, overall yields are very low, making efficient biosynthesis an attractive means of production. PMID:27405846

  2. Genetic recombination in Streptomyces griseus.

    PubMed Central

    Parag, Y

    1978-01-01

    Low-frequency (10(-6)) genetic recombination was observed in a cephamycin-producing strain of Streptomyces griseus. The recombinants were predominantly heteroclones. Heteroclone analysis was performed involving four heteroclones of one cross. In 100 mutants correlation was found between the type of auxotrophy and the level of antibiotic activity. A cross of this strain with a streptomycin-producing strain of S. griesus is described. PMID:415037

  3. Novel Biotransformations of 7-Ethoxycoumarin by Streptomyces griseus

    PubMed Central

    Sariaslani, F. Sima; Rosazza, John P.

    1983-01-01

    Biotransformation of 7-ethoxycoumarin by Streptomyces griseus resulted in the accumulation of two metabolites which were isolated and identified as 7-hydroxycoumarin and 7-hydroxy-6-methoxycoumarin. A novel series of biotransformation reactions is implicated in the conversion of the ethoxycoumarin substrate to these products, including O-deethylation, 6-hydroxylation to form a 6,7-dihydroxycoumarin catechol, and subsequent O-methylation. Either 7-hydroxycoumarin or 6,7-dihydroxycoumarin was biotransformed to 7-hydroxy-6-methoxycoumarin by S. griseus. Trace amounts of the isomeric 6-hydroxy-7-methoxycoumarin were detected when 6,7-dihydroxycoumarin was used as the substrate. Efforts to obtain a cell-free catechol-O-methyltransferase enzyme system from S. griseus were unsuccessful. However, [methyl-14C]methionine was used with cultures of S. griseus to form 7-hydroxy-6-[14C]methoxycoumarin. PMID:16346369

  4. Primary structure of Streptomyces griseus metalloendopeptidase II.

    PubMed

    Kojima, S; Kumazaki, T; Ishii, S; Miura, K

    1998-07-01

    Streptomyces griseus metalloendopeptidase II (SGMPII) is a unique protease, since it shows anomalous susceptibility to the proteinaceous "serine protease inhibitors" produced by Streptomyces, such as Streptomyces subtilisin inhibitor (SSI) and its homologous proteins. In this study, we analyzed the amino acid sequence of SGMPII by analyzing various peptide fragments produced enzymatically. The sequence of SGMPII, which is composed of 334 amino acids, showed no extensive similarity to SSI-insensitive metalloproteases produced by other species of Streptomyces, except for the amino acid residues essential for catalysis and zinc binding. However, SGMPII is 35-41% similar to thermolysin and its related metalloproteases, which are not inhibited by SSI, and the residues presumed to be critical for catalysis and zinc-binding are well conserved in SGMPII. Glu137 in a "His-Glu-Xaa-His" motif of SGMPII was identified as the residue modified by CICH2 CO-DL-(N-OH)Leu-Ala-Gly-NH2, an active-site-directed irreversible inhibitor of thermolysin-like metalloproteases. Based on the sequence comparison of SGMPII and other bacterial metalloproteases, we discuss the structural basis for the differences in substrate specificity and stability between SGMPII and other thermolysin-like proteases. A possible SSI-binding locus of SGMPII is also proposed. PMID:9720222

  5. Echolocation in the Risso's dolphin, Grampus griseus

    NASA Astrophysics Data System (ADS)

    Philips, Jennifer D.; Nachtigall, Paul E.; Au, Whitlow W. L.; Pawloski, Jeffrey L.; Roitblat, Herbert L.

    2003-01-01

    The Risso's dolphin (Grampus griseus) is an exclusively cephalopod-consuming delphinid with a distinctive vertical indentation along its forehead. To investigate whether or not the species echolocates, a female Risso's dolphin was trained to discriminate an aluminum cylinder from a nylon sphere (experiment 1) or an aluminum sphere (experiment 2) while wearing eyecups and free swimming in an open-water pen in Kaneohe Bay, Hawaii. The dolphin completed the task with little difficulty despite being blindfolded. Clicks emitted by the dolphin were acquired at average amplitudes of 192.6 dB re 1 μPa, with estimated sources levels up to 216 dB re 1 μPa-1 m. Clicks were acquired with peak frequencies as high as 104.7 kHz (Mfp=47.9 kHz), center frequencies as high as 85.7 kHz (Mf0=56.5 kHz), 3-dB bandwidths up to 94.1 kHz (MBW=39.7 kHz), and root-mean-square bandwidths up to 32.8 kHz (MRMS=23.3 kHz). Click durations were between 40 and 70 μs. The data establish that the Risso's dolphin echolocates, and that, aside from slightly lower amplitudes and frequencies, the clicks emitted by the dolphin were similar to those emitted by other echolocating odontocetes. The particular acoustic and behavioral findings in the study are discussed with respect to the possible direction of the sonar transmission beam of the species.

  6. Managing diversity: Domestication and gene flow in Stenocereus stellatus Riccob. (Cactaceae) in Mexico

    PubMed Central

    Cruse-Sanders, Jennifer M; Parker, Kathleen C; Friar, Elizabeth A; Huang, Daisie I; Mashayekhi, Saeideh; Prince, Linda M; Otero-Arnaiz, Adriana; Casas, Alejandro

    2013-01-01

    Microsatellite markers (N = 5) were developed for analysis of genetic variation in 15 populations of the columnar cactus Stenocereus stellatus, managed under traditional agriculture practices in central Mexico. Microsatellite diversity was analyzed within and among populations, between geographic regions, and among population management types to provide detailed insight into historical gene flow rates and population dynamics associated with domestication. Our results corroborate a greater diversity in populations managed by farmers compared with wild ones (HE = 0.64 vs. 0.55), but with regional variation between populations among regions. Although farmers propagated S. stellatus vegetatively in home gardens to diversify their stock, asexual recruitment also occurred naturally in populations where more marginal conditions have limited sexual recruitment, resulting in lower genetic diversity. Therefore, a clear-cut relationship between the occurrence of asexual recruitment and genetic diversity was not evident. Two managed populations adjacent to towns were identified as major sources of gene movement in each sampled region, with significant migration to distant as well as nearby populations. Coupled with the absence of significant bottlenecks, this suggests a mechanism for promoting genetic diversity in managed populations through long distance gene exchange. Cultivation of S. stellatus in close proximity to wild populations has led to complex patterns of genetic variation across the landscape that reflects the interaction of natural and cultural processes. As molecular markers become available for nontraditional crops and novel analysis techniques allow us to detect and evaluate patterns of genetic diversity, genetic studies provide valuable insights into managing crop genetic resources into the future against a backdrop of global change. Traditional agriculture systems play an important role in maintaining genetic diversity for plant species. PMID:23762520

  7. Transmission beam characteristics of a Risso's dolphin (Grampus griseus).

    PubMed

    Smith, Adam B; Kloepper, Laura N; Yang, Wei-Cheng; Huang, Wan-Hsiu; Jen, I-Fan; Rideout, Brendan P; Nachtigall, Paul E

    2016-01-01

    The echolocation system of the Risso's dolphin (Grampus griseus) remains poorly studied compared to other odontocete species. In this study, echolocation signals were recorded from a stationary Risso's dolphin with an array of 16 hydrophones and the two-dimensional beam shape was explored using frequency-dependent amplitude plots. Click source parameters were similar to those already described for this species. Centroid frequency of click signals increased with increasing sound pressure level, while the beamwidth decreased with increasing center frequency. Analysis revealed primarily single-lobed, and occasionally vertically dual-lobed, beam shapes. Overall beam directivity was found to be greater than that of the harbor porpoise, bottlenose dolphin, and a false killer whale. The relationship between frequency content, beam directivity, and head size for this Risso's dolphin deviated from the trend described for other species. These are the first reported measurements of echolocation beam shape and directivity in G. griseus. PMID:26827004

  8. Regulation of trehalose metabolism by Streptomyces griseus spores.

    PubMed Central

    McBride, M J; Ensign, J C

    1990-01-01

    Spores of Streptomyces griseus contain trehalose and trehalase, but trehalose is not readily hydrolyzed until spore germination is initiated. Trehalase in crude extracts of spores, germinated spores, and mycelia of S. griseus had a pH optimum of approximately 6.2, had a Km value for trehalose of approximately 11 mM, and was most active in buffers having ionic strengths of 50 to 200 mM. Inhibitors or activators or trehalase activity were not detected in extracts of spores or mycelia. Several lines of evidence indicated that trehalose and trehalase are both located in the spore cytoplasm. Spores retained their trehalose and most of their trehalase activity following brief exposure to dilute acid. Protoplasts formed by enzymatic removal of the spore walls in buffer containing high concentrations of solutes also retained their trehalose and trehalase activity. Protoplasts formed in buffer containing lower levels of solutes contained low levels of trehalose. The mechanism by which trehalose metabolism is regulated in S. griseus spores is unresolved. A low level of hydration of the cytoplasm of the dormant spores and an increased level of hydration during germination may account for the apparent inactivity of trehalase in dormant spores and the rapid hydrolysis of trehalose upon initiation of germination. Images PMID:2113908

  9. Microbial colonization of injured cactus tissue (Stenocereus gummosus) and its relationship to the ecology of cactophilic Drosophila mojavensis.

    PubMed Central

    Fogleman, J C; Foster, J L

    1989-01-01

    Necrotic tissue of agria cactus (Stenocereus gummosus) serves as a feeding and breeding substrate for Drosophila mojavensis. This fly species is one of the four endemic Drosophila species in the Sonoran Desert. Freeze injuries were created in arms of agria cactus in Mexico to study the events of microbial colonization. Facultative anaerobic bacteria were the first microbes to be detected, and the exclusion of large arthropods by covering the injuries with netting did not affect bacterial colonization. Yeast growth lagged behind bacterial growth by 2 days, and excluding arthropods delayed the detection of yeasts by an additional 2 days. Thus, insects (such as Drosophila species) and other arthropods do play a role in the colonization of agria rots by yeasts. All injuries were attractive to D. mojavensis within 5 days, and these flies were shown to be carrying significant densities of both bacteria and yeasts. Analysis of the volatile compounds present in the developing rots over time indicated that the volatile pattern is dynamic. Ethanol and acetic acid were the two volatile substances most likely responsible for the initial attraction of the injuries for Drosophila species. PMID:2705763

  10. Quantification of polyphenols and flavonoid content and evaluation of anti-inflammatory and antimicrobial activities of Stenocereus stellatus extracts.

    PubMed

    Soto-Cabrera, Diego; Salazar, Juan R; Nogueda-Gutiérrez, Inés; Torres-Olvera, Mariana; Cerón-Nava, Anabelle; Rosales-Guevara, Juan; Terrazas, Teresa; Rosas-Acevedo, Hortensia

    2016-08-01

    The hexanic, ethyl acetate and methanolic extracts from branches of Stenocereus stellatus were tested in both the 12-O-tetradecanoylphorbol-13-acetate (TPA) - induced ear oedema model and antimicrobial activity assay. The % of oedema inhibition, the Minimum Inhibitory Concentration (MIC), as well as the polyphenolic and flavonoid content were determined. Also, extracts were analysed by gas chromatography-mass spectrometry (GC-MS). In TPA model, the three extracts showed moderate oedema inhibition. In the antimicrobial activity assay, methanolic extract shows better MIC against all strains. The lowest MICs were for Candida albicans (31 μg/mL) and Rhizopus sp. (15 μg/mL). Also, 50.78 mg eq. of gallic acid/g extract of polyphenol and 115.12 mg eq. of catequine/g extract of flavonoids content were founded in ethyl acetate extract. In the chromatographic analysis, β-sitosterol, β-amyrine, betulin and some other molecules were identified. The results show that S. stellatus possess antimicrobial activities against some fungus species. PMID:26395173

  11. Engineering the primary substrate specificity of Streptomyces griseus trypsin.

    PubMed

    Page, Michael J; Wong, Sui-Lam; Hewitt, Jeff; Strynadka, Natalie C J; MacGillivray, Ross T A

    2003-08-01

    Streptomyces griseus trypsin (SGT) was chosen as a model scaffold for the development of serine proteases with enhanced substrate specificity. Recombinant SGT has been produced in a Bacillus subtilis expression system in a soluble active form and purified to homogeneity. The recombinant and native proteases have nearly identical enzymatic properties and structures. Four SGT mutants with alterations in the S1 substrate binding pocket (T190A, T190P, T190S, and T190V) were also expressed. The T190P mutant demonstrated the largest shift to a preference for Arg versus Lys in the P1 site. This was shown by a minor reduction in catalytic activity toward an Arg-containing substrate (k(cat) reduction of 25%). The crystal structures of the recombinant SGT and the T190P mutant in a complex with the inhibitor benzamidine were obtained at high resolution (approximately 1.9 A). The increase in P1 specificity, achieved with minimal effect on the catalytic efficiency, demonstrates that the T190P mutant is an ideal candidate for the design of additional substrate specificity engineered into the S2 to S4 binding pockets. PMID:12885239

  12. Purification and characterization of Streptomyces griseus metalloendopeptidases I and II.

    PubMed

    Tsuyuki, H; Kajiwara, K; Fujita, A; Kumazaki, T; Ishii, S

    1991-09-01

    Two metalloendopeptidases, designated as Streptomyces griseus metalloendopeptidases I and II (SGMPI and SGMPII), were isolated from a commercial Pronase P by a method including affinity chromatography on carbobenzoxy-L-alaninyl-triethylenetetraminyl-Sepharose (Z-Ala-T-Sepharose). The two enzymes differed from each other in behavior on ion-exchange chromatography but showed the same amino-terminal sequence at least up to the 20th residue. Their molecular weights were both estimated to be 37,000 by SDS-polyacrylamide gel electrophoresis. Elemental and amino acid composition analyses indicated that both of them contained about 1 g atom of zinc and one cystine residue per mol of protein. Cleavage specificities of the two enzymes toward synthetic peptide-substrates were very similar to those observed with thermolysin. EDTA, o-phenanthroline, and phosphoramidon strongly inhibited these enzymes, while typical serine-protease inhibitors and cysteine-protease inhibitors had no effect. The findings clearly indicate that SGMPI and SGMPII can be classified into the family of zinc-endopeptidases. It was unexpectedly found, however, that these metalloendopeptidases were strongly inhibited by protein serine-protease inhibitors produced by Streptomycetes, such as Streptomyces subtilisin inhibitor (SSI), alkaline protease inhibitor-2c' (API-2c'), and plasminostreptin (PS). PMID:1769959

  13. Studies on biological reduction of chromate by Streptomyces griseus.

    PubMed

    Poopal, Ashwini C; Laxman, R Seeta

    2009-09-30

    Chromium is a toxic heavy metal used in various industries and leads to environmental pollution due to improper handling. The most toxic form of chromium Cr(VI) can be converted to less toxic Cr(III) by reduction. Among the actinomycetes tested for chromate reduction, thirteen strains reduced Cr(VI) to Cr(III), of which one strain of Streptomyces griseus (NCIM 2020) was most efficient showing complete reduction within 24h. The organism was able to use a number of carbon sources as electron donors. Sulphate, nitrate, chloride and carbonate had no effect on chromate reduction during growth while cations such as Cd, Ni, Co and Cu were inhibitory to varying degrees. Chromate reduction was associated with the bacterial cells and sonication was the best method of cell breakage to release the enzyme. The enzyme was constitutive and did not require presence of chromate during growth for expression of activity. Chromate reduction with cell free extract (CFE) was observed without added NADH. However, addition of NAD(P)H resulted in 2-3-fold increase in activity. Chromate reductase showed optimum activity at 28 degrees C and pH 7. PMID:19410364

  14. [Lysis of the cell walls of streptococcus group A by Streptomyces griseus pronase].

    PubMed

    Savel'ev, E P; Petrov, G I

    1978-01-01

    The effect of Streptomyces griseus pronase on Streptococcus group A cell walls was studied. Cell walls were shown to be lysed by pronase, the lysis level being dependent on the molarity of the potassium-phosphate buffer used. With an increase in the buffer molarity from 0.005 M to 0.05 M lysis of cell walls decreased from 70-80% to 30%. By DEAE-cellulose chromatography lysates were separated into two fractions the first of which contained a group specific polysaccharide. A preparative method of obtaining a group specific polysaccharide of Streptococcus group A using Streptomyces griseus pronase under mild conditions is described. PMID:416431

  15. DISSEMINATED TOXOPLASMOSIS IN A MEDITERRANEAN PREGNANT RISSO'S DOLPHIN (GRAMPUS GRISEUS) WITH TRANSPLACENTAL FETAL INFECTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatal disseminated toxoplasmosis was diagnosed in a Risso's dolphin (Grampus griseus) dam and its fetus based on pathologic findings, immunohistochemistry, and the structure of the parasite. The dolphin was stranded alive on the Spanish Mediterranean coast, and died a few hrs later. At necropsy the ...

  16. Purification of an antifungal endochitinase from a potential biocontrol Agent Streptomyces griseus.

    PubMed

    Rabeeth, M; Anitha, A; Srikanth, Geetha

    2011-08-15

    Streptomyces griseus (MTCC 9723) is a chitinolytic bacterium isolated from prawn cultivated pond soil of Peddapuram Village; East Godavari District was studied in detailed. Chitinase (EC 3.2.1.14) was extracted from the culture filtrate of Streptomyces griseus and purified by ammonium sulfate precipitation, DEAE-cellulose ionexchange chromatography, Sephadex G-100 and Sephadex G-200 gel filtration chromatography. The molecular mass of the purified chitinase was estimated to be 34, 32 kDa by SDS gel electrophoresis and confirmed by activity staining with Calcofluor White M2R. Chitinase was optimally active at pH of 6.0 and at 40 degrees C. The enzyme was stable from pH 5-9 and up to 20-50 degrees C. The chitinase exhibited Km and Vmax values of 400 mg and 180 IU mL(-1) for colloidal chitin. Among the metals and inhibitors that were tested, the Hg+, Hg2+ and P-chloromercuribenzoic acid completely inhibited the chitinase activity at 1 mM concentration. The purified chitinase showed high activity on colloidal chitin, chitobiose, and chitooligosaccharide. An in vitro assay proved that the crude chitinase, actively growing cells of S. griseus having antifungal activity against all studied fungal pathogen. This result implies that characteristics of S. griseus producing endochitinase made them suitable for biotechnological purpose such as for degradation of chitin containing waste and it might be a promising biocontrol agent for plant pathogens. PMID:22545353

  17. Interaction of trypsin-like protease from Streptomyces griseus with an immobilized inhibitor from kidney bean.

    PubMed

    Mosolov, V V; Fedurkina, N V; Valueva, T A

    1978-01-12

    An immobilized double-headed inhibitor from Phaseolus vulgaris L. selectively binds the trypsin-like enzyme produced by Streptomyces griseus. Binding takes place at pH 8.0, and at pH 2.0 the protease can be quantitatively released from the complex. Purified by affinity chromatography, the trypsin-like enzyme is homogeneous according to polyacrylamide gel electrophoresis and ultracentrifugation data. Physico-chemical and enzymic properties of the enzyme are identical to those exhibited by the enzyme purified by ion-exchange chromatography. Chymoelastases from Str. griseus as well as the subtilisin-like enzyme do not interact with an immobilized inhibitor. In solution, the inhibitor from P. vulgaris gives a stable ternary complex with bovine trypsin and chymotrypsin, whereas with an immobilized inhibitor the trypsin, if present, tends to displace chymotrypsin in an chymotrypsin inhibitor complex. This evidence suggests that immobilization results in considerable changes in inhibitor properties. PMID:413581

  18. Molecular characterization of a gene encoding a photolyase from Streptomyces griseus.

    PubMed Central

    Kobayashi, T; Takao, M; Oikawa, A; Yasui, A

    1989-01-01

    By using a synthetic DNA probe derived from an amino acid sequence in the most conserved region of three known photolyases (Escherichia coli, Anacystis nidulans and Saccharomyces cerevisiae), we isolated a DNA fragment containing two long open reading frames (ORFs) from a genomic DNA library of Streptomyces griseus. One ORF encodes a polypeptide of 455 amino acids (Mr 50594), which exhibits substantial similarities with the other three photolyases. Photoreactivation-repair deficient E. coli cells could be converted into photoreactivatable ones by introduction of plasmids harboring this ORF, indicating that this is the photolyase gene of S. griseus. The deduced aa sequence of Streptomyces photolyase was most similar to that of E. coli. The putative DNA binding site as well as cofactor binding regions were proposed. Images PMID:2501760

  19. Transcriptional Control by A-Factor of Two Trypsin Genes in Streptomyces griseus

    PubMed Central

    Kato, Jun-ya; Chi, Won-Jae; Ohnishi, Yasuo; Hong, Soon-Kwang; Horinouchi, Sueharu

    2005-01-01

    AdpA is the key transcriptional activator for a number of genes of various functions in the A-factor regulatory cascade in Streptomyces griseus, forming an AdpA regulon. Trypsin-like activity was detected at a late stage of growth in the wild-type strain but not in an A-factor-deficient mutant. Consistent with these observations, two trypsin genes, sprT and sprU, in S. griseus were found to be members of the AdpA regulon; AdpA activated the transcription of both genes by binding to the operators located at about −50 nucleotide positions with respect to the transcriptional start point. The transcription of sprT and sprU, induced by AdpA, was most active at the onset of sporulation. Most trypsin activity exerted by S. griseus was attributed to SprT, because trypsin activity in an sprT-disrupted mutant was greatly reduced but that in an sprU-disrupted mutant was only slightly reduced. This was consistent with the observation that the amount of the sprT mRNA was much greater than that of the sprU transcript. Disruption of both sprT and sprU (mutant ΔsprTU) reduced trypsin activity to almost zero, indicating that no trypsin genes other than these two were present in S. griseus. Even the double mutant ΔsprTU grew normally and developed aerial hyphae and spores over the same time course as the wild-type strain. PMID:15601713

  20. Genome Sequence of the Streptomycin-Producing Microorganism Streptomyces griseus IFO 13350▿ †

    PubMed Central

    Ohnishi, Yasuo; Ishikawa, Jun; Hara, Hirofumi; Suzuki, Hirokazu; Ikenoya, Miwa; Ikeda, Haruo; Yamashita, Atsushi; Hattori, Masahira; Horinouchi, Sueharu

    2008-01-01

    We determined the complete genome sequence of Streptomyces griseus IFO 13350, a soil bacterium producing an antituberculosis agent, streptomycin, which is the first aminoglycoside antibiotic, discovered more than 60 years ago. The linear chromosome consists of 8,545,929 base pairs (bp), with an average G+C content of 72.2%, predicting 7,138 open reading frames, six rRNA operons (16S-23S-5S), and 66 tRNA genes. It contains extremely long terminal inverted repeats (TIRs) of 132,910 bp each. The telomere's nucleotide sequence and secondary structure, consisting of several palindromes with a loop sequence of 5′-GGA-3′, are different from those of typical telomeres conserved among other Streptomyces species. In accordance with the difference, the chromosome has pseudogenes for a conserved terminal protein (Tpg) and a telomere-associated protein (Tap), and a novel pair of Tpg and Tap proteins is instead encoded by the TIRs. Comparisons with the genomes of two related species, Streptomyces coelicolor A3(2) and Streptomyces avermitilis, clarified not only the characteristics of the S. griseus genome but also the existence of 24 Streptomyces-specific proteins. The S. griseus genome contains 34 gene clusters or genes for the biosynthesis of known or unknown secondary metabolites. Transcriptome analysis using a DNA microarray showed that at least four of these clusters, in addition to the streptomycin biosynthesis gene cluster, were activated directly or indirectly by AdpA, which is a central transcriptional activator for secondary metabolism and morphogenesis in the A-factor (a γ-butyrolactone signaling molecule) regulatory cascade in S. griseus. PMID:18375553

  1. An ABC transporter involved in the control of streptomycin production in Streptomyces griseus.

    PubMed

    Takano, Hideaki; Toriumi, Naoe; Hirata, Mariko; Amano, Taisuke; Ohya, Takaaki; Shimada, Reona; Kusada, Hiroyuki; Amano, Sho-Ichi; Matsuda, Ko-Ichi; Beppu, Teruhiko; Ueda, Kenji

    2016-07-01

    We screened for a gene that inhibits streptomycin production in Streptomyces griseus when it is introduced on a high-copy-number plasmid pIJ702, and obtained a plasmid pKM545. The introduction of pKM545 abolished streptomycin production on all media tested including YMP-sugar and Nutrient broth. S1 protection analysis demonstrated that the introduction of this plasmid downregulated the transcriptional activity of the promoter preceding strR, the pathway-specific transcriptional regulator for streptomycin biosynthesis. The 2.8-kb BamHI fragment cloned onto pKM545 contained two coding sequences SGR_5442 and 5443. These coding sequences and the two downstream ones (SGR_5444 and 5445) constituted a possible operon structure designated to be rspABCD (regulation of streptomycin production). RspB and RspC exhibited a marked similarity with an ATP-binding domain and a membrane-associating domain of an ABC-2 type transporter, respectively, suggesting that the Rsp proteins comprise a membrane exporter. The gene cluster consisting of the rsp operon and the upstream divergent small coding sequence (SGR_5441) was widely distributed to Streptomyces genome. An rspB mutant of S. griseus produced 3-fold streptomycin of the parental strain in YMP liquid medium. The evidence implies that the Rsp translocator is involved in the export of a substance that specifies the expression level of streptomycin biosynthesis genes in S. griseus. PMID:27268270

  2. Detection and properties of A-factor-binding protein from Streptomyces griseus

    SciTech Connect

    Miyake, K.; Horinouchi, S.; Yoshida, M.; Chiba, N.; Mori, K.; Nogawa, N.; Morikawa, N.; Beppu, T. )

    1989-08-01

    The optically active form of tritium-labeled A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone), a pleiotropic autoregulator responsible for streptomycin production, streptomycin resistance, and sporulation in Streptomyces griseus, was chemically synthesized. By using the radioactive A-factor, a binding protein for A-factor was detected in the cytoplasmic fraction of this organism. The binding protein had an apparent molecular weight of approximately 26,000, as determined by gel filtration. Scatchard analysis suggested that A-factor bound the protein in the molar ratio of 1:1 with a binding constant, Kd, of 0.7 nM. The number of the binding protein was roughly estimated to be 37 per genome. The inducing material virginiae butanolide C (VB-C), which has a structure very similar to that of A-factor and is essential for virginiamycin production in Streptomyces virginiae, did not inhibit binding. In addition, no protein capable of specifically binding {sup 3}H-labeled VB-C was found in S. griseus. Together with the observation that VB-C had almost no biological activity on the restoration of streptomycin production or sporulation in an A-factor-deficient mutant of S. griseus, these results indicated that the binding protein had a strict ligand specificity. Examination for an A-factor-binding protein in Streptomyces coelicolor A3(2) and Streptomyces lividans showed the absence of any specifically binding protein.

  3. Synthetic analogues of chymostatin. Inhibition of chymotrypsin and Streptomyces griseus proteinase A.

    PubMed Central

    Tomkinson, N P; Galpin, I J; Beynon, R J

    1992-01-01

    A series of analogues of chymostatin, including Z-Arg-Leu-Phe-aldehyde (Z-Arg-Leu-Phe-H), have been synthesized. Analysis of the inhibitory potential of these analogues permits identification of residues and interactions that are important for inhibitory activity. Moreover, the structure-function relationship for Z-Arg-Leu-Phe-H and chymostatin inhibition of chymotrypsin and Streptomyces griseus proteinase A (SGPA) was probed further with the aid of molecular mechanics. This analysis identified interactions that provide an explanation for the enhanced activity of the natural product, chymostatin, over the synthetic analogues in the inhibition of chymotrypsin but not SGPA. PMID:1530579

  4. Multicentric Benign Epithelial Inclusions in a Free-ranging Risso's Dolphin (Grampus griseus).

    PubMed

    Diaz-Delgado, J; Quesada-Canales, O; Arbelo, M; Sierra, E; Edwards, J F; Suarez-Bonnet, A; Santana-Suarez, C; Espinosa de Los Monteros, A; Fernandez, A

    2016-01-01

    This report describes the histological and immunohistochemical features of multicentric, benign, epithelial inclusions (BEIs) in a free-ranging, adult, female Risso's dolphin (Grampus griseus). The differential diagnoses included ectopic hamartomatous epithelial inclusions, non-Müllerian choristoma, Müllerian choristoma and low-grade metastatic carcinoma/mesothelioma. The most likely diagnosis of such BEIs was multicentric, embolic, reactive mesothelium, as suggested by cytomorphological and immunophenotypical features of the BEIs, the occurrence of focal pleural rupture and the immunophenotype of the pleural mesothelium. The former represents a pathological condition not previously reported in a marine mammal species, rarely described in animals, and relatively infrequently recognized in man. PMID:27392421

  5. Differential Regulation of ftsZ Transcription during Septation of Streptomyces griseus

    PubMed Central

    Kwak, Jangyul; Dharmatilake, Amitha J.; Jiang, Hao; Kendrick, Kathleen E.

    2001-01-01

    Streptomyces has been known to form two types of septa. The data in this research demonstrated that Streptomyces griseus forms another type of septum near the base of sporogenic hyphae (basal septum). To understand the regulation of the septation machinery in S. griseus, we investigated the expression of the ftsZ gene. S1 nuclease protection assays revealed that four ftsZ transcripts were differentially expressed during morphological differentiation. The vegetative transcript (emanating from Pveg) is present at a moderate level during vegetative growth, but is switched off within the first 2 h of sporulation. Two sporulation-specific transcripts predominantly accumulated, and the levels increased by approximately fivefold together shortly before sporulation septa begin to form. Consistently, the sporulation-specific transcripts were expressed much earlier and more abundantly in a group of nonsporulating mutants that form their sporulation septa prematurely. Promoter-probe studies with two different reporter systems confirmed the activities of the putative promoters identified from the 5′ end point of the transcripts. The levels and expression timing of promoter activities were consistent with the results of nuclease protection assays. The aseptate phenotype of the Pspo mutant indicated that the increased transcription from Pspo is required for sporulation septation, but not for vegetative or basal septum formation. PMID:11489862

  6. Purification of histidase from Streptomyces griseus and nucleotide sequence of the hutH structural gene.

    PubMed Central

    Wu, P C; Kroening, T A; White, P J; Kendrick, K E

    1992-01-01

    Histidine ammonia-lyase (histidase) was purified to homogeneity from vegetative mycelia of Streptomyces griseus. The enzyme was specific for L-histidine and showed no activity against the substrate analog, D-histidine. Histidinol phosphate was a potent competitive inhibitor. Histidase displayed saturation kinetics with no detectable sigmoidal response. Neither thiol reagents nor a variety of divalent cations had any effect on the activity of the purified enzyme. High concentrations of potassium cyanide inactivated histidase in the absence of its substrate or histidinol phosphate, suggesting that, as in other histidases, dehydroalanine plays an important role in catalysis. The N-terminal amino acid sequence of histidase was used to construct a mixed oligonucleotide probe to identify and clone the histidase structural gene, hutH, from genomic DNA of the wild-type strain of S. griseus. The cloned DNA restored the ability of a histidase structural gene mutant to grow on L-histidine as the sole nitrogen source. The deduced amino acid sequence of hutH shows significant relatedness with histidase from bacteria and a mammal as well as phenylalanine ammonia-lyase from plants and fungi. Images PMID:1537807

  7. Molecular cloning of tetracycline resistance genes from Streptomyces rimosus in Streptomyces griseus and characterization of the cloned genes.

    PubMed Central

    Ohnuki, T; Katoh, T; Imanaka, T; Aiba, S

    1985-01-01

    Two tetracycline resistance genes of Streptomyces rimosus, an oxytetracycline producer, were cloned in Streptomyces griseus by using pOA15 as a vector plasmid. Expression of the cloned genes, designated as tetA and tetB was inducible in S. griseus as well as in the donor strain. The tetracycline resistance directed by tetA and tetB was characterized by examining the uptake of tetracycline and in vitro polyphenylalanine synthesis by the sensitive host and transformants with the resultant hybrid plasmids. Polyphenylalanine synthesis with crude ribosomes and the S150 fraction from S. griseus carrying the tetA plasmid was resistant to tetracycline, and, by a cross-test of ribosomes and S150 fraction coming from both the sensitive host and the resistant transformant, the resistance directed by tetA was revealed to reside mainly in crude ribosomes and slightly in the S150 fraction. However, the resistance in the crude ribosomes disappeared when they were washed with 1 M ammonium chloride. These results suggest that tetA specified the tetracycline resistance of the machinery for protein synthesis not through ribosomal subunits, but via an unidentified cytoplasmic factor. In contrast, S. griseus carrying the tetB plasmid accumulated less intracellular tetracycline than did the host, and the protein synthesis by reconstituting the ribosomes and S150 fraction was sensitive to the drug. Therefore, it is conceivable that tetB coded a tetracycline resistance determinant responsible for the reduced accumulation of tetracycline. Images PMID:2982781

  8. Evolution under domestication: ongoing artificial selection and divergence of wild and managed Stenocereus pruinosus (Cactaceae) populations in the Tehuacán Valley, Mexico

    PubMed Central

    Parra, Fabiola; Casas, Alejandro; Peñaloza-Ramírez, Juan Manuel; Cortés-Palomec, Aurea C.; Rocha-Ramírez, Víctor; González-Rodríguez, Antonio

    2010-01-01

    Background and Aims The Tehuacán Valley in Mexico is a principal area of plant domestication in Mesoamerica. There, artificial selection is currently practised on nearly 120 native plant species with coexisting wild, silvicultural and cultivated populations, providing an excellent setting for studying ongoing mechanisms of evolution under domestication. One of these species is the columnar cactus Stenocereus pruinosus, in which we studied how artificial selection is operating through traditional management and whether it has determined morphological and genetic divergence between wild and managed populations. Methods Semi-structured interviews were conducted with 83 households of three villages to investigate motives and mechanisms of artificial selection. Management effects were studied by comparing variation patterns of 14 morphological characters and population genetics (four microsatellite loci) of 264 plants from nine wild, silvicultural and cultivated populations. Key Results Variation in fruit characters was recognized by most people, and was the principal target of artificial selection directed to favour larger and sweeter fruits with thinner or thicker peel, fewer spines and pulp colours others than red. Artificial selection operates in agroforestry systems favouring abundance (through not felling plants and planting branches) of the preferred phenotypes, and acts more intensely in household gardens. Significant morphological divergence between wild and managed populations was observed in fruit characters and plant vigour. On average, genetic diversity in silvicultural populations (HE = 0·743) was higher than in wild (HE = 0·726) and cultivated (HE = 0·700) populations. Most of the genetic variation (90·58 %) occurred within populations. High gene flow (NmFST > 2) was identified among almost all populations studied, but was slightly limited by mountains among wild populations, and by artificial selection among wild and managed populations. Conclusions

  9. Interactions of Streptomyces serine-protease inhibitors with Streptomyces griseus metalloendopeptidase II.

    PubMed

    Kajiwara, K; Fujita, A; Tsuyuki, H; Kumazaki, T; Ishii, S

    1991-09-01

    Streptomyces griseus metalloendopeptidase II (SGMPII) was shown to form tight complexes with several Streptomyces protein inhibitors which had been believed to be specific to serine proteases, such as Streptomyces subtilisin inhibitor (SSI), plasminostreptin (PS), and alkaline protease inhibitor-2c' (API-2c'), as well as with Streptomyces metalloprotease inhibitor (SMPI). The dissociation constants of complexes between SGMPII and these inhibitors were successfully determined by using a novel fluorogenic bimane-peptide substrate. The values ranged from nM to pM. The results of studies by gel chromatographic and enzymatic analyses indicated that SGMPII is liberated from the complex with SSI by the addition of subtilisin BPN'. SGMPII and subtilisin BPN' proved, therefore, to interact with SSI in a competitive manner, despite the difference in the chemical nature of their active sites. PMID:1769961

  10. Aeromonas dhakensis pneumonia and sepsis in a neonate Risso's dolphin Grampus griseus from the Mediterranean Sea.

    PubMed

    Pérez, Lola; Abarca, M Lourdes; Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Figueras, M José; Domingo, Mariano

    2015-09-17

    A neonate Risso's dolphin Grampus griseus was found stranded alive on a beach in Catalonia, Spain. Rehabilitation attempts were unsuccessful and it died 2 d later, showing pneumonia and sepsis. A pure bacterial culture was obtained from all tissues and blood and identified as Aeromonas hydrophila using the API 20NE. However, sequencing the rpoD gene showed that the strain in fact belongs to A. dhakensis, making this the first report of fatal haemorrhagic-necrotizing pneumonia and sepsis due to this species in a marine mammal. The A. dhakensis strain GMV-704 produced β-haemolysis, possessed several virulence genes and showed sensitivity to several antimicrobials. This study provides a new potential host for A. dhakensis, and its potential virulence in dolphins and its presence in the marine environment may warrant considering this species a potential threat to marine mammals. PMID:26378409

  11. A modular family 19 chitinase found in the prokaryotic organism Streptomyces griseus HUT 6037.

    PubMed Central

    Ohno, T; Armand, S; Hata, T; Nikaidou, N; Henrissat, B; Mitsutomi, M; Watanabe, T

    1996-01-01

    The specificity of chitinase C-1 of Streptomyces griseus HUT 6037 for the hydrolysis of the beta-1,4-glycosidic linkages in partially acetylated chitosan is different from that of other microbial chitinases. In order to study the primary structure of this unique chitinase, the chiC gene specifying chitinase C-1 was cloned and its nucleotide sequence was determined. The gene encodes a polypeptide of 294 amino acids with a calculated size of 31.4 kDa. Comparison of the amino acid sequence of the deduced polypeptide with that of other proteins revealed a C-terminal catalytic domain displaying considerable sequence similarity to the catalytic domain of plant class I, II, and IV chitinases which form glycosyl hydrolase family 19. The N-terminal domain of the deduced polypeptide exhibits sequence similarity to substrate-binding domains of several microbial chitinases and cellulases but not to the chitin-binding domains of plant chitinases. The previously purified chitinase C-1 from S. griseus is suggested to be generated by proteolytic removal of the N-terminal chitin-binding domain and corresponds to the catalytic domain of the chitinase encoded by the chiC gene. High-performance liquid chromatography analysis of the hydrolysis products from N-acetyl chitotetraose revealed that chitinase C-1 catalyzes hydrolysis of the glycosidic bond with inversion of the anomeric configuration, in agreement with the previously reported inverting mechanism of plant class I chitinases. This is the first report of a family 19 chitinase found in an organism other than higher plants. PMID:8752320

  12. Biofiltration technology for the removal of toluene from polluted air using Streptomyces griseus.

    PubMed

    Mohamed, Elham F; Awad, Gamal; Andriantsiferana, Caroline; El-Diwany, Ahmed I

    2016-05-01

    Biofiltration technology has been recognized as a promising biotechnology for treating the volatile organic compounds (VOCs) present in polluted air. This study aims to investigate the performance of a biofiltration system of Streptomyces griseus sp. DSM-40759 immobilized on activated carbon (PICA S23) towards the adsorption and degradation of toluene vapour as well as to regenerate the activated carbon in situ. The batch studies were performed using nutrient agar medium and basal salt medium (BSM) for microbial growth. Initially the pre-cultures were incubated at a temperature of 28°C on a rotary shaker at 150 rpm. After two days, the strain S. griseus DSM-40759 was immobilized on a known weight of activated carbon (12 g). The results of biofilter performance showed three different stages with a quick adsorption phase with approximately 95% of toluene removal after 70 min, a slow biotransformation phase by immobilized cells. In the later, the removal efficiency decreased significantly with the extension of time and reached 60% during this stage. Moreover, a final quick removal phase by the immobilized cells had an average removal efficiency of toluene around 95% after 500 min. The toluene degradation was found to be more than 84% after the second cycle and the biofilter was still capable of removing additional toluene. Thus, the results demonstrated the feasibility and reusability of a new biofilter system for toluene removal as well as extending the activated carbon's capacity and this could be a potential solution to reuse the activated carbon in industrial application. PMID:26469210

  13. Landscape management and domestication of Stenocereus pruinosus (Cactaceae) in the Tehuacán Valley: human guided selection and gene flow

    PubMed Central

    2012-01-01

    Background Use of plant resources and ecosystems practiced by indigenous peoples of Mesoamerica commonly involves domestication of plant populations and landscapes. Our study analyzed interactions of coexisting wild and managed populations of the pitaya Stenocereus pruinosus, a columnar cactus used for its edible fruit occurring in natural forests, silviculturally managed in milpa agroforestry systems, and agriculturally managed in homegardens of the Tehuacán Valley, Mexico. We aimed at analyzing criteria of artificial selection and their consequences on phenotypic diversity and differentiation, as well as documenting management of propagules at landscape level and their possible contribution to gene flow among populations. Methods Semi-structured interviews were conducted to 83 households of the region to document perception of variation, criteria of artificial selection, and patterns of moving propagules among wild and managed populations. Morphological variation of trees from nine wild, silviculturally and agriculturally managed populations was analyzed for 37 characters through univariate and multivariate statistical methods. In addition, indexes of morphological diversity (MD) per population and phenotypic differentiation (PD) among populations were calculated using character states and frequencies. Results People recognized 15 pitaya varieties based on their pulp color, fruit size, form, flavor, and thorniness. On average, in wild populations we recorded one variety per population, in silviculturally managed populations 1.58 ± 0.77 varieties per parcel, and in agriculturally managed populations 2.19 ± 1.12 varieties per homegarden. Farmers select in favor of sweet flavor (71% of households interviewed) and pulp color (46%) mainly red, orange and yellow. Artificial selection is practiced in homegardens and 65% of people interviewed also do it in agroforestry systems. People obtain fruit and branches from different population types and move

  14. Accumulation of silicon in cacti native to the United States: characterization of silica bodies and cyclic oligosiloxanes in Stenocereus thurberi, Opuntia littoralis, Opuntia ficus-indica, and Opuntia stricta.

    PubMed

    Wright, Cynthia R; Waddell, Emanuel A; Setzer, William N

    2014-06-01

    Four different cactus species growing in the United States, Stenocereus thurberi growing in Organ Pipe Cactus National Monument, Arizona, Opuntia littoralis and Opuntia ficus-indica, growing on Santa Catalina Island, California, and Opuntia stricta, growing in northern Alabama, were examined for the presence of silica bodies (opaline phytoliths). Silica bodies were found in all four of these cactus species, parallelepiped-shaped crystals in S. thurberi, and starburst-shaped crystalline structures in the three Opuntia species. In addition, the essential oils of the four cactus species were obtained by hydrodistillation and analyzed by gas chromatography - mass spectrometry. To our surprise, S. thurberi, O. littoralis, and O. ficus-indica (but not O. stricta) essential oils contained cyclic oligosiloxanes. To our knowledge, cyclic oligosiloxanes have not been previously found as essential oil components. PMID:25115104

  15. Evidence suggests vocal production learning in a cross-fostered Risso's dolphin (Grampus griseus).

    PubMed

    Favaro, Livio; Neves, Silvana; Furlati, Stefano; Pessani, Daniela; Martin, Vidal; Janik, Vincent M

    2016-07-01

    Vocal learning is a rare skill in mammals, and we have limited information about the contexts in which they use it. Previous studies suggested that cetaceans in general are skilled at imitating sounds, but only few species have been studied to date. To expand this investigation to another species and to investigate the possible influence of the social environment on vocal learning, we studied the whistle repertoire of a female Risso's dolphin (Grampus griseus) that was stranded at an early age and was subsequently raised in a group of bottlenose dolphins (Tursiops truncatus). We show that this cross-fostered animal produced vocal signals more akin to those of its Tursiops poolmates than those of Risso's dolphins in the wild. This is one of very few systematic cross-fostering studies in cetaceans and the first to suggest vocal production learning in the Risso's dolphin. Our findings also suggest that social experience is a major factor in the development of the vocal repertoire in this species. PMID:26874843

  16. Inhibition of Streptomyces griseus metallo-endopeptidase II (SGMPII) by active-site-directed inhibitors.

    PubMed

    Kumazaki, T; Ishii, S; Yokosawa, H

    1994-03-01

    Inactivation of Streptomyces griseus metallo-endopeptidase II (SGMPII) by ClCH2CO-DL-(N-OH)Leu-OCH3 and by ClCH2CO-DL-(N-OH)Leu-Ala-Gly-NH2 was studied kinetically. These reagents cause irreversible inhibition of the enzyme in a pseudo-first order reaction, and the inhibition reaction exhibits saturation kinetics. The second-order rate constants for inactivation of SGMPII by ClCH2CO-DL-(N-OH)Leu-OCH3 and by ClCH2CO-DL-(N-OH)Leu-Ala-Gly-NH2 were measured to be 0.12 and 8.9 M-1.s-1, respectively. The order of affinities of metallo-endopeptidases towards these irreversible inhibitors is thermolysin > SGMPII > Pseudomonas aeruginosa elastase. A competitive inhibitor of SGMPII, L-Val-L-Trp, protects the enzyme against inactivation by ClCH2CO-DL-(N-OH)Leu-Ala-Gly-NH2 in a competitive manner. Furthermore, the pH profile of the inactivation closely resembles that for the hydrolysis of synthetic peptide substrates by the enzyme. These findings suggest that these reagents bind reversibly and react irreversibly at the active site of the enzyme. PMID:8056768

  17. Streptomyces griseus aminopeptidase is a calcium-activated zinc metalloprotein. Purification and properties of the enzyme.

    PubMed

    Spungin, A; Blumberg, S

    1989-08-01

    A heat-stable aminopeptidase with an N-terminal Ala-Pro-Asp-Ile-Pro-Leu sequence has been purified from Streptomyces griseus by heat treatment followed by gel-exclusion and anion-exchange chromatographic procedures. The enzyme is a monomeric zinc metalloenzyme showing an apparent molecular mass of 33 kDa by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and 21 kDa by gel filtration on Superose 12. Calcium ions bind to the enzyme, pKCa 4.5, and activate it about sixfold when the substrate is leucine-4-nitroanilide (0.4 mM in 50 mM Tris/HCl pH 8.0, 25 degrees C). Binding of Ca2+ also contributes to the thermal stability of the protein. This aminopeptidase may be useful for two-stage assays of bacterial and mammalian metalloendopeptidases; it may also serve in studies of proteolytic enzyme activation by calcium ions. PMID:2503378

  18. Improved Production of Active Streptomyces griseus Trypsin with a Novel Auto-Catalyzed Strategy

    PubMed Central

    Zhang, Yunfeng; Ling, Zhenmin; Du, Guocheng; Chen, Jian; Kang, Zhen

    2016-01-01

    N-terminal sequences play crucial roles in regulating expression, translation, activation and enzymatic properties of proteins. To reduce cell toxicity of intracellular trypsin and increase secretory expression, we developed a novel auto-catalyzed strategy to produce recombinant trypsin by engineering the N-terminus of mature Streptomyces griseus trypsin (SGT). The engineered N-terminal peptide of SGT was composed of the thioredoxin, glycine-serine linker, His6-tag and the partial bovine trypsinogen pro-peptide (DDDDK). Furthermore, we constructed a variant TLEI with insertion of the artificial peptide at N-terminus and site-directed mutagenesis of the autolysis residue R145. In fed-batch fermentation, the production of extracellular trypsin activity was significantly improved to 47.4 ± 1.2 U·ml−1 (amidase activity, 8532 ± 142.2 U·ml−1 BAEE activity) with a productivity of 0.49 U·ml−1·h−1, which was 329% greater than that of parent strain Pichia pastoris GS115-SGT. This work has significant potential to be scaled-up for microbial production of SGT. In addition, the N-terminal peptide engineering strategy can be extended to improve heterologous expression of other toxic enzymes. PMID:26983398

  19. Hearing abilities and sound reception of broadband sounds in an adult Risso's dolphin (Grampus griseus).

    PubMed

    Mooney, T Aran; Yang, Wei-Cheng; Yu, Hsin-Yi; Ketten, Darlene R; Jen, I-Fan

    2015-08-01

    While odontocetes do not have an external pinna that guides sound to the middle ear, they are considered to receive sound through specialized regions of the head and lower jaw. Yet odontocetes differ in the shape of the lower jaw suggesting that hearing pathways may vary between species, potentially influencing hearing directionality and noise impacts. This work measured the audiogram and received sensitivity of a Risso's dolphin (Grampus griseus) in an effort to comparatively examine how this species receives sound. Jaw hearing thresholds were lowest (most sensitive) at two locations along the anterior, midline region of the lower jaw (the lower jaw tip and anterior part of the throat). Responses were similarly low along a more posterior region of the lower mandible, considered the area of best hearing in bottlenose dolphins. Left- and right-side differences were also noted suggesting possible left-right asymmetries in sound reception or differences in ear sensitivities. The results indicate best hearing pathways may vary between the Risso's dolphin and other odontocetes measured. This animal received sound well, supporting a proposed throat pathway. For Risso's dolphins in particular, good ventral hearing would support their acoustic ecology by facilitating echo-detection from their proposed downward oriented echolocation beam. PMID:25925434

  20. Faeriefungin: a new broad-spectrum antibiotic from Streptomyces griseus var. autotrophicus.

    PubMed

    Nair, M G; Putnam, A R; Mishra, S K; Mulks, M H; Taft, W H; Keller, J E; Miller, J R; Zhu, P P; Meinhart, J D; Lynn, D G

    1989-01-01

    Faeriefungin, a polyol polyene macrolide lactone antibiotic, was isolated from the mycelium of Streptomyces griseus var. autotrophicus, MSU-32058/ATCC 53668, collected from the soil sample of a fairy ring in an old lawn in Lansing, Michigan. Faeriefungin has some properties similar to the previously reported polyene macrolides, mycoticin and flavofungin, but possesses different physiochemical and biological properties. Aspergillus, Fusarium, Microsporum, Trichophyton, and Alternaria spp. were completely inhibited by faeriefungin at 3.2 micrograms/ml, Candida spp. at 5.5 micrograms/ml, and Pythium, Phialophora, Leptosphaeria spp., and some selected Gram-negative penicillin-resistant strains of Neisseria gonorrhoeae at 16.0 micrograms/ml. At a concentration of 100 ppm, it caused 100% mortality of mosquito larvae (Aedes aegypti, Rockefeller strain) and free-living nematodes (Panagrellus redivivus). Unlike the related polyene macrolides, faeriefungin is crystalline and stable with broad-spectrum antimicrobial and insecticidal activity. Preliminary cytotoxicity studies with human erythrocytes and rat liver epithelial cells indicated that faeriefungin and amphotericin B have comparable toxicity. Solution nmr study has indicated that faeriefungin is a mixture of two compounds, faerifungins A [1] and B [2], and that they differ in the attachment of a H or an Me at C-33. PMID:2509636

  1. Distribution of the Lyme Disease Spirochete Borrelia burgdorferi in Naturally and Experimentally Infected Western Gray Squirrels (Sciurus griseus)

    PubMed Central

    Jensen, Kelly; Salkeld, Daniel J.; Lane, Robert S.

    2010-01-01

    Abstract The dynamics of Borrelia burgdorferi infections within its natural hosts are poorly understood. We necropsied four wild-caught western gray squirrels (Sciurus griseus) that were acquired during a previous study that evaluated the reservoir competence of this rodent for the Lyme disease spirochete. One animal was infected experimentally, whereas the others were infected in the wild before capture. To investigate dissemination of B. burgdorferi and concurrent histopathologic lesions in different tissues, blood specimens, synovial and cerebrospinal fluid, ear-punch biopsies, and diverse tissue samples from skin and various organs were taken and examined by culture, polymerase chain reaction, and histology. Borrelia-positive cultures were obtained from three of the squirrels, that is, from skin biopsies (7 of 20 samples), ear-punch biopsies (2 of 8), and one (1 of 5) lymph node. Sequencing of amplicons confirmed B. burgdorferi sensu stricto (s.s.) infection in 9 of 10 culture-positive samples and in DNA extracted from all 10 positive cultures. The experimentally infected squirrel yielded most of the positive samples. In contrast, bodily fluids, all other organ specimens from these animals, and all samples from one naturally infected squirrel were negative for Borrelia for both assays. None of the necropsied squirrels exhibited specific clinical signs associated with B. burgdorferi. Similarly, necropsy and histological examination of tissues indicated the presence of underlying infectious processes, none of which could be ascribed conclusively to B. burgdorferi infection. Based on these results, obtained from a small number of animals investigated at a single time point, we suggest that B. burgdorferi s.s. infection in S. griseus may result in rather localized dissemination of spirochetes, and that mild or nonclinical disease might be more common after several months of infection duration. Since spirochetes could be detected in squirrels 7–21 months

  2. Interaction of Streptomyces subtilisin inhibitor (SSI) with Streptomyces griseus metallo-endopeptidase II (SGMP II).

    PubMed

    Kumazaki, T; Kajiwara, K; Kojima, S; Miura, K; Ishii, S

    1993-10-01

    We have unexpectedly found that Streptomyces subtilisin inhibitor (SSI) and some other similar serine protease inhibitors produced by Streptomycetes strongly inhibit Streptomyces griseus metallo-endopeptidase II (SGMP II) [Kajiwara, K. et al. (1991) J. Biochem. 110, 350-354]. In order to elucidate the mode of their unusual interaction with SGMP II in more detail, we prepared twelve kinds of SSI analogues, in which one or two amino acid residues in the peptide segment from Thr64 to Val74 of wild-type SSI had been replaced or deleted by site-directed mutagenesis, and determined the dissociation constants of their complexes with SGMP II. Six analogues among them showed dissociation constants one order of magnitude lower than that of the wild type. Three had higher values. The results suggest that at least some residues in this segment are interacting with SGMP II in the complex. We also prepared an SSI mutant in which the disulfide bridge between Cys71 and Cys101 had been eliminated by replacing the two Cys residues with Ser residues. This mutated SSI inhibited SGMP II as strongly as the wild-type SSI did. While peptide bonds in the wild-type molecule did not suffer from the hydrolytic action of SGMP II except those at the amino-terminal fragile portion, the Pro72-Met73 bond of the mutant was specifically cleaved by the enzyme. This peptide bond, therefore, seems to play the role of the reactive site in the interaction of SSI with SGMP II. PMID:8276770

  3. Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei.

    PubMed

    Nakamura, Itsumi; Meyer, Carl G; Sato, Katsufumi

    2015-01-01

    We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two species of deep-sea sharks (bluntnose sixgill sharks, Hexanchus griseus, and a prickly shark, Echinorhinus cookei) in their natural habitat, we used accelerometer-magnetometer data loggers to measure their swimming performance. Both species of deep-sea sharks showed similar diel vertical migrations: they swam at depths of 200-300 m at night and deeper than 500 m during the day. Ambient water temperature was around 15°C at 200-300 m but below 7°C at depths greater than 500 m. During vertical movements, all deep-sea sharks showed higher swimming efforts during descent than ascent to maintain a given swimming speed, and were able to glide uphill for extended periods (several minutes), indicating that these deep-sea sharks are in fact positively buoyant in their natural habitats. This positive buoyancy may adaptive for stealthy hunting (i.e. upward gliding to surprise prey from underneath) or may facilitate evening upward migrations when muscle temperatures are coolest, and swimming most sluggish, after spending the day in deep, cold water. Positive buoyancy could potentially be widespread in fish conducting daily vertical migration in deep-sea habitats. PMID:26061525

  4. Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei

    PubMed Central

    Nakamura, Itsumi; Meyer, Carl G.; Sato, Katsufumi

    2015-01-01

    We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two species of deep-sea sharks (bluntnose sixgill sharks, Hexanchus griseus, and a prickly shark, Echinorhinus cookei) in their natural habitat, we used accelerometer-magnetometer data loggers to measure their swimming performance. Both species of deep-sea sharks showed similar diel vertical migrations: they swam at depths of 200–300 m at night and deeper than 500 m during the day. Ambient water temperature was around 15°C at 200–300 m but below 7°C at depths greater than 500 m. During vertical movements, all deep-sea sharks showed higher swimming efforts during descent than ascent to maintain a given swimming speed, and were able to glide uphill for extended periods (several minutes), indicating that these deep-sea sharks are in fact positively buoyant in their natural habitats. This positive buoyancy may adaptive for stealthy hunting (i.e. upward gliding to surprise prey from underneath) or may facilitate evening upward migrations when muscle temperatures are coolest, and swimming most sluggish, after spending the day in deep, cold water. Positive buoyancy could potentially be widespread in fish conducting daily vertical migration in deep-sea habitats. PMID:26061525

  5. A small lytic polysaccharide monooxygenase from Streptomyces griseus targeting α- and β-chitin.

    PubMed

    Nakagawa, Yuko S; Kudo, Madoka; Loose, Jennifer S M; Ishikawa, Takahiro; Totani, Kazuhide; Eijsink, Vincent G H; Vaaje-Kolstad, Gustav

    2015-03-01

    The lytic polysaccharide monooxygenases (LPMOs) have received considerable attention subsequent to their discovery because of their ability to boost the enzymatic conversion of recalcitrant polysaccharides. In the present study, we describe the enzymatic properties of SgLPMO10F, a small (15 kDa) auxilliary activity (AA) family 10 LPMO from Streptomyces griseus belonging to a clade of the phylogenetic tree without any characterized representative. The protein was expressed using a Brevibacillus-based expression system that had not been used previously for LPMO expression and that also ensures correct processing of the N-terminus crucial for LPMO activity. The enzyme was active towards both α- and β-chitin and showed stronger binding and a greater release of soluble oxidized products for the latter allomorph. In chitinase synergy assays, however, SgLPMO10F worked slightly better for α-chitin, increasing chitin solubilization yields by up to 30-fold and 20-fold for α- and β-chitin, respectively. Synergy experiments with various chitinases showed that the addition of SgLPMO10F leads to a substantial increase in the (GlcNAc)2 :GlcNAc product ratio, in reactions with α-chitin only. This underpins the structural differences between the substrates and also shows that, on α-chitin, SgLPMO10F affects the binding mode and/or degree of processivity of the chitinases tested. Variation in the only exposed aromatic residue in the substrate-binding surface of LPMO10s has previously been linked to preferential binding for α-chitin (exposed Trp) or β-chitin (exposed Tyr). Mutation of this residue, Tyr56, in SgLPMO10F to Trp had no detectable effect on substrate-binding preferences but, in synergy experiments, the mutant appeared to be more efficient on α-chitin. PMID:25605134

  6. Gender, season and management affect fecal glucocorticoid metabolite concentrations in captive goral (Naemorhedus griseus) in Thailand.

    PubMed

    Khonmee, Jaruwan; Brown, Janine L; Rojanasthien, Suvichai; Aunsusin, Anurut; Thumasanukul, Dissakul; Kongphoemphun, Adisorn; Siriaroonrat, Boripat; Tipkantha, Wanlaya; Punyapornwithaya, Veerasak; Thitaram, Chatchote

    2014-01-01

    Chinese goral (Naemorhedus griseus) are a threatened species in Thailand and the focus of captive breeding for possible reintroduction. However, little is known of their biology or what factors in the captive environment affect welfare. Our objective was to determine the impact of gender, season, and management on goral adrenal activity. We hypothesized that differences in fecal glucocorticoid concentrations would be related to animal density. Fecal samples were collected 3 days/week for 1 year from 63 individuals (n = 32 males, 31 females) at two facilities that house the majority of goral in Thailand: Omkoi Wildlife Sanctuary (Omkoi), an off-exhibit breeding center that houses goral in individual pens (16 pens; n = 8 males, 8 females) and in small family groups (8 pens; n = 8 males, 8 females); and the Chiang Mai Night Safari (NS), a zoo that maintains 31 goral (n = 17 males, 14 females) in one large pen. Glucocorticoid metabolite concentrations were higher in male than female goral at Omkoi throughout the year, and there was a seasonal effect on adrenal activity (p<0.05). Goral at Omkoi and NS were used to test the effect of animal density on fecal glucocorticoid excretion of goral housed in similar-sized enclosures. Overall, the highest levels were found at NS (n = 31 adults/pen; 27 m2 per animal) compared to Omkoi (n = 2 adults/pen; 400 m2 per animal) (p<0.05). Overall findings support our hypothesis that animal density and aspects of the captive environment impact adrenal steroid activity in captive goral. In addition, gender and season also had significant effects on glucocorticoid metabolite production. Potential stressors pertaining to the welfare of this species were identified, which will guide future efforts to improve management and create self-sustaining and healthy populations of this threatened species. PMID:24637886

  7. Gender, Season and Management Affect Fecal Glucocorticoid Metabolite Concentrations in Captive Goral (Naemorhedus griseus) in Thailand

    PubMed Central

    Khonmee, Jaruwan; Brown, Janine L.; Rojanasthien, Suvichai; Aunsusin, Anurut; Thumasanukul, Dissakul; Kongphoemphun, Adisorn; Siriaroonrat, Boripat; Tipkantha, Wanlaya; Punyapornwithaya, Veerasak; Thitaram, Chatchote

    2014-01-01

    Chinese goral (Naemorhedus griseus) are a threatened species in Thailand and the focus of captive breeding for possible reintroduction. However, little is known of their biology or what factors in the captive environment affect welfare. Our objective was to determine the impact of gender, season, and management on goral adrenal activity. We hypothesized that differences in fecal glucocorticoid concentrations would be related to animal density. Fecal samples were collected 3 days/week for 1 year from 63 individuals (n = 32 males, 31 females) at two facilities that house the majority of goral in Thailand: Omkoi Wildlife Sanctuary (Omkoi), an off-exhibit breeding center that houses goral in individual pens (16 pens; n = 8 males, 8 females) and in small family groups (8 pens; n = 8 males, 8 females); and the Chiang Mai Night Safari (NS), a zoo that maintains 31 goral (n = 17 males, 14 females) in one large pen. Glucocorticoid metabolite concentrations were higher in male than female goral at Omkoi throughout the year, and there was a seasonal effect on adrenal activity (p<0.05). Goral at Omkoi and NS were used to test the effect of animal density on fecal glucocorticoid excretion of goral housed in similar-sized enclosures. Overall, the highest levels were found at NS (n = 31 adults/pen; 27 m2 per animal) compared to Omkoi (n = 2 adults/pen; 400 m2 per animal) (p<0.05). Overall findings support our hypothesis that animal density and aspects of the captive environment impact adrenal steroid activity in captive goral. In addition, gender and season also had significant effects on glucocorticoid metabolite production. Potential stressors pertaining to the welfare of this species were identified, which will guide future efforts to improve management and create self-sustaining and healthy populations of this threatened species. PMID:24637886

  8. Characterization of ssfR and ssgA, Two Genes Involved in Sporulation of Streptomyces griseus

    PubMed Central

    Jiang, Hao; Kendrick, Kathleen E.

    2000-01-01

    In the presence of cefoxitin, which inhibits septum formation during sporulation, Streptomyces griseus is unable to sporulate, retaining the sonication sensitivity of nonsporulating hyphae. Cefoxitin- and sonication-resistant mutant SKK2600 was isolated and showed many morphological differences from its parental strain. A 3.6-kb DNA fragment that complemented the mutations of SKK2600 contained two open reading frames (ORFs), either of which could complement SKK2600. One ORF, designated ssfR, encoded a protein containing a potential DNA-binding helix-turn-helix motif close to its N terminus. SsfR is similar to members of a large family of transcriptional regulators, particularly IclR of Escherichia coli. The second ORF was identified as ssgA, a previously described sporulation gene from S. griseus (S. Kawamoto and J. C. Ensign, Actinomycetology 9:136–151, 1995). A point mutation of C to T seven nucleotides upstream of the UGA stop codon of ssfR was responsible for the phenotype of isolated mutant strain SKK2600. Surprisingly, this mutation should not change the primary structure of SsfR. The ssfR and ssgA disruption mutants were constructed and showed the “white” mutant phenotype, with some growth medium dependence. In addition, the ssfR null mutant sporulated ectopically in phosphate starvation medium. PMID:10986257

  9. Effects of geolocation archival tags on reproduction and adult body mass of sooty shearwaters (Puffinus griseus)

    USGS Publications Warehouse

    Adams, J.; Scott, D.; McKechnie, S.; Blackwell, G.; Shaffer, S.A.; Moller, H.

    2009-01-01

    We attached 11 g (1.4% body-mass equivalent) global location sensing (GLS) archival tag packages to tarsi of 25 breeding sooty shearwaters (Puffinus griseus, titi) on Whenua Hou (Codfish Island), New Zealand during the chick-rearing period in 2005. Compared with chicks reared by non-handled adults that did not carry tags, deployment of tags on one or both adult parents ultimately resulted in 35% reduction in chick body mass and significantly reduced chick skeletal size preceding fledging (19 April). However, body mass between chick groups was not significantly different after controlling for skeletal size. Effects on chicks were more pronounced in six pairs where both parents carried tags. Chick mass was negatively related to the duration that adults carried tags. In this study, none of the chicks reared by pairs where both parents were tagged, 54% of chicks reared by pairs where one parent was tagged, and 83% of chicks reared by non-handled and non-tagged parents achieved a previously determined pre-fledging mass threshold (564 g; Sagar & Horning 1998). Body mass of adults carrying tags and returning from transequatorial migration the following year were 4% lighter on average than non-tagged birds, but this difference was not statistically significant. Reduced mass among chicks reared by adults carrying tags during the chick-provisioning period indicated that adults altered "normal" provisioning behaviours to maintain their own body condition at the expense of their chicks. Population-level information derived from telemetry studies can reveal important habitat-linked behaviours, unique aspects of seabird foraging behaviours, and migration ecology. Information for some species (e.g., overlap with fisheries) can aid conservation and marine ecosystem management. We advise caution, however, when interpreting certain data related to adult provisioning behaviours (e.g., time spent foraging, provisioning rates, etc.). If effects on individuals are of concern, we suggest

  10. Assessment of ovarian activity in captive goral (Naemorhedus griseus) using noninvasive fecal steroid monitoring.

    PubMed

    Khonmee, Jaruwan; Brown, Janine L; Taya, Kazuyoshi; Rojanasthien, Suvichai; Punyapornwithaya, Veerasak; Thumasanukul, Dissakul; Kongphoemphun, Adisorn; Siriaroonrat, Boripat; Tipkantha, Wanlaya; Pongpiachan, Petai; Thitaram, Chatchote

    2014-10-15

    To date, there is no information on gonadal steroidogenic activity of female goral (Naemorhedus griseus), a threatened species of Thailand. Captive goral populations have been established to produce animals for ex situ conservation and reintroduction, but as yet none are self-sustaining. The objectives of the present study were to (1) determine the influence of season on ovarian steriodogenic function; and (2) examine the relationship between gonadal hormone excretion and sexual behaviors throughout the year. Fecal samples were collected 5 to 7 days/wk for 15 months from 8 adult females housed at Omkoi Wildlife Breeding Center in Thailand and analyzed for ovarian steroid metabolites using validated enzyme immunoassays. Observations of sexual behaviors and mating were conducted each morning for 30 min/session. Based on fecal estrogen and progestagen metabolite concentrations, the overall estrous cycle length was about 21 days, with a 2- to 3-day follicular phase and an 18- to 20-day luteal phase. Sexual behaviors, most notably tail-up, increased for 2 to 3 days during the time estrogens were elevated during mating. Fecal progestagens were elevated during luteal phases and increased further during gestation, which lasted approximately 7 months. The lactation period was 5 months, and females were anestrus for 2 to 5 of those months, with the exception of one that cycled continuously throughout. Two females conceived around 2 months postpartum and so were pregnant during lactation. Birth records over the past 21 years indicated young are born throughout the year. This combined with the hormonal data suggests that female gorals are not strongly seasonal, at least in captivity, although there was considerable variation among females in estrogen and progestagen patterns. In conclusion, fecal steroid metabolite monitoring is an effective means of assessing ovarian function in this species and will be a useful tool for breeding management and planned development of

  11. Epidemiological studies on intestinal helminth parasites of the patagonian grey fox (Pseudalopex griseus) in Tierra del Fuego, Patagonia Argentina.

    PubMed

    Zanini, Fabián; Laferrara, Miguel; Bitsch, Matías; Pérez, Héctor; Elissondo, Maria Celina

    2006-03-31

    The present work was performed to study the intestinal helminths of the patagonian grey fox (Pseudalopex griseus) and to obtain information about its possible role in the sylvatic life cycle of Echinococcu granulosus in Tierra del Fuego, Patagonia Argentina. Eighty-one foxes were captured and subject to post-mortem analysis. Thirty-one foxes (38.3%) harboured helminths. A total of six helminth species were recovered. Only one adult of E. granulosus was found in the studied samples. The current study is the first report of the intestinal helminths of the patagonian grey fox in Tierra del Fuego, Argentina and showed that this specie is probably not an important reservoir host for E. granulosus. PMID:16414190

  12. CebR as a master regulator for cellulose/cellooligosaccharide catabolism affects morphological development in Streptomyces griseus.

    PubMed

    Marushima, Kazuya; Ohnishi, Yasuo; Horinouchi, Sueharu

    2009-10-01

    Streptomyces griseus mutants exhibiting deficient glucose repression of beta-galactosidase activity on lactose-containing minimal medium supplemented with a high concentration of glucose were isolated. One of these mutants had a 12-bp deletion in cebR, which encodes a LacI/GalR family regulator. Disruption of cebR in the wild-type strain caused the same phenotype as the mutant, indicating that CebR is required for glucose repression of beta-galactosidase activity. Recombinant CebR protein bound to a 14-bp inverted-repeat sequence (designated the CebR box) present in the promoter regions of cebR and the putative cellobiose utilization operon, cebEFG-bglC. The DNA-binding activity of CebR was impaired by cellooligosaccharides, including cellobiose, cellotriose, cellotetraose, cellopentaose, and cellohexaose. In agreement with this observation, transcription from the cebE and cebR promoters was greatly enhanced by the addition of cellobiose to the medium. Seven other genes containing one or two CebR boxes in their upstream regions were found in the S. griseus genome. Five of these genes encode putative secreted proteins: two cellulases, a cellulose-binding protein, a pectate lyase, and a protein of unknown function. These five genes and cebEFG-bglC were transcribed at levels 4 to 130 times higher in the DeltacebR mutant than in the wild-type strain, as determined by quantitative reverse transcription-PCR. These findings indicate that CebR is a master regulator of cellulose/cellooligosaccharide catabolism. Unexpectedly, the DeltacebR mutant formed very few aerial hyphae on lactose-containing medium, demonstrating a link between carbon source utilization and morphological development. PMID:19648249

  13. Biosynthesis of the antitumor chromomycin A3 in Streptomyces griseus: analysis of the gene cluster and rational design of novel chromomycin analogs.

    PubMed

    Menéndez, Nuria; Nur-e-Alam, Mohammad; Braña, Alfredo F; Rohr, Jürgen; Salas, José A; Méndez, Carmen

    2004-01-01

    The biosynthetic gene cluster of the aureolic acid type antitumor drug chromomycin A3 from S. griseus subsp. griseus has been identified and characterized. It spans 43 kb and contains 36 genes involved in polyketide biosynthesis and modification, deoxysugar biosynthesis and sugar transfer, pathway regulation and resistance. The organization of the cluster clearly differs from that of the closely related mithramycin. Involvement of the cluster in chromomycin A3 biosynthesis was demonstrated by disrupting the cmmWI gene encoding a polyketide reductase involved in side chain reduction. Three novel chromomycin derivatives were obtained, named chromomycin SK, chromomycin SA, and chromomycin SDK, which show antitumor activity and differ with respect to their 3-side chains. A pathway for the biosynthesis of chromomycin A3 and its deoxysugars is proposed. PMID:15112992

  14. Purification and characterization of an acidic amino acid specific endopeptidase of Streptomyces griseus obtained from a commercial preparation (Pronase).

    PubMed

    Yoshida, N; Tsuruyama, S; Nagata, K; Hirayama, K; Noda, K; Makisumi, S

    1988-09-01

    A protease was purified 163-fold from Pronase, a commercial product from culture filtrate of Streptomyces griseus, by a series of column chromatographies on CM-Toyopearl (Fractogel), Sephadex G-50, hydroxyapatite, and Z-Gly-D-Phe-AH-Sepharose 4B using Boc-Ala-Ala-Pro-Glu-pNA as a substrate. The final preparation was homogeneous by polyacrylamide gel electrophoresis (PAGE), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), and gel isoelectric focusing. Studies on the substrate specificity with peptide p-nitroanilides revealed that this protease preferentially hydrolyzed peptide bonds on the carbonyl-terminal side of either glutamic acid or aspartic acid. It was most active at pH 8.8 for the hydrolysis of Boc-Ala-Ala-Pro-Glu-pNA. The molecular weight of the protease was estimated to be 20,000 by gel filtration on Sepharose 6B using 6 M guanidine hydrochloride as an eluent, and 22,000 by SDS-PAGE in the presence of 2-mercaptoethanol. The isoelectric point of the enzyme was 8.4. The enzyme was inactivated by diisopropyl phosphofluoridate (DFP) but not by p-chloromercuribenzoate (PCMB) or EDTA. PMID:3149277

  15. First isolation of Leptospira interrogans from Lycalopex griseus (South American gray fox) in Argentina shows new MLVA genotype.

    PubMed

    Scialfa, Exequiel; Brihuega, Bibiana; Venzano, Agustín; Morris, Winston Eduardo; Bolpe, Jorge; Schettino, Mateo

    2013-01-01

    To identify carriers of Leptospira spp. in Argentina, wild animals were trapped in Buenos Aires Province during three nights, capturing 12 Didelphis albiventris (white-eared opossum), six Chaetophractus villosus (big hairy armadillo), five Lycalopex griseus (South American gray fox), and two Conepatus chinga (Molina's hog-nosed skunk). All were tested by microscopic agglutination test, and five (two gray foxes, two armadillos, and one skunk) were positive for Leptospira interrogans serovars Canicola and Icterohaemorrhagiae, L. borgpetersenii serovar Castellonis, and L. kirschneri serovar Grippotyphosa, at titers of 1:50 and 1:100. Kidney tissue from all animals was cultured, and one isolate of L. interrogans from a gray fox was obtained. Hamsters inoculated with the isolate died after 6 days with no macroscopic lesions at necropsy. However, histologic examination revealed glomerulonephritis, interstitial nephritis, and pneumonia. The Leptospira strain from the South American gray fox was analyzed serologically and its pathogenicity was established. Genotyping through multiple-locus variable-number tandem repeat analysis showed that the strain was a new genotype related to the L. interrogans serogroup Icterohaemorrhagiae. PMID:23307384

  16. Copper Levels in Tissues of Dolphins Tursiops truncatus, Stenella coeruleoalba and Grampus griseus from the Croatian Adriatic Coast.

    PubMed

    Bilandžić, Nina; Đokić, Maja; Sedak, Marija; Đuras, Martina; Gomerčić, Tomislav; Benić, Miroslav

    2016-09-01

    Copper concentrations were determined in muscle, liver, kidney, spleen and lung tissues of three dolphin species. Dolphins of Tursiops truncatus (young and adult), Stenella coeruleoalba and Grampus griseus were stranded along the Croatian coast. Concentrations in tissues of all three dolphin species were highest in the liver (4.92-16.5 μg/g) followed by kidney (2.85-5.29 μg/g). Similar levels were measured in muscle, spleen and lung in range 1.13-3.67 μg/g. Statistics analysis showed significant differences of Cu concentrations for muscle (p = 0.008), kidney (p = 0.04) and liver (p = 0.02) between the three dolphin species. Also, for all three species significant differences between tissue types of the same species were determined (p < 0.001, all). However, there were no significant differences in Cu levels of the same tissues between males and females within same species. Also, significant differences of body length and weight between three dolphin were found (p < 0.001, both). PMID:27246724

  17. Intracellular distribution of estradiol and estrogen binding sites in the uterus and oviducts of the green monkey (cercopithecus griseus)

    SciTech Connect

    Alekseeva, M.L.; Fanchenko, N.D.; Novikov, E.A.; Shchedrina, R.N.

    1986-03-01

    This paper describes a comparative investigation of changes in estradoil (E/sub 2/) and progesterone (P) concentrations in the blood plasma and concentrations of E/sub 2/ and estrogen binding sites (EBS) in the uterus and oviducts of C. griseus in the course of the menstrual cycle. A 0.25 aqueous solution of sucrose, 10mM Tris-HC1 buffer containing 1.5 mM EDTA, a 0.1M phosphate buffer containing 0.01% and 0.1% gelatin, antisera against E/sub 2/-17beta and P, labeled 3 /SUB H/ -E/sub 2/-17beta and /sup 3/H-P (specific radioactivity 104 and 96 Ci/nmole respectively), and their unlabeled analogs, 0.5, 1, and 5% suspensions of activated charcoal in buffer with the addition of 0.1% gelatin, and scintillation fluid consisting of 0.5% PPO and 0.05% POPOP in toluene were used. Indirect evidence shows the absence of any additional intracellular mechanisms affecting translocation of activated cytoplasmic estrogenreceptor complexes into the nucleus.

  18. [Effect of preservation conditions on the viability and activity of Streptomyces griseus--producer of the antibiotic grizin].

    PubMed

    Trenina, G A; Lavrova, L N; Iustratova, L S; Kuklin, V V

    1983-03-01

    Strain AURIGenetics- 1552 of Str. griseus producing grisin used as a feed additive was obtained in the course of stepped selection. It is deposited at the Central Collection of Industrial Microorganisms of the USSR and designated as strain S-248. The strain was stored under varying conditions and their effect on its viability, morphological variation and antibiotic potency was studied. Investigation of the strain variation with respect to the cultural and morphological properties and the antibiotic production revealed definite correlation between the morphological properties of the culture and its capacity for the synthesis of the antibiotic. The medium G-1 containing KNO3 as the only source of nitrogen was found to be advantageous for maintaining the strain potency on storage with the method of subcultures or under a layer of mineral oil. It was shown that the strain can be successfully stored by lyophilization. This method in combination with selection of active variants from populations of lyophilized cells provided not only maintenance of the culture potency at the required level but also its increase. PMID:6407387

  19. Observations on Abundance of Bluntnose Sixgill Sharks, Hexanchus griseus, in an Urban Waterway in Puget Sound, 2003-2005

    PubMed Central

    Griffing, Denise; Larson, Shawn; Hollander, Joel; Carpenter, Tim; Christiansen, Jeff; Doss, Charles

    2014-01-01

    The bluntnose sixgill shark, Hexanchus griseus, is a widely distributed but poorly understood large, apex predator. Anecdotal reports of diver-shark encounters in the late 1990’s and early 2000’s in the Pacific Northwest stimulated interest in the normally deep-dwelling shark and its presence in the shallow waters of Puget Sound. Analysis of underwater video documenting sharks at the Seattle Aquarium’s sixgill research site in Elliott Bay and mark-resight techniques were used to answer research questions about abundance and seasonality. Seasonal changes in relative abundance in Puget Sound from 2003–2005 are reported here. At the Seattle Aquarium study site, 45 sixgills were tagged with modified Floy visual marker tags, along with an estimated 197 observations of untagged sharks plus 31 returning tagged sharks, for a total of 273 sixgill observations recorded. A mark-resight statistical model based on analysis of underwater video estimated a range of abundance from a high of 98 sharks seen in July of 2004 to a low of 32 sharks seen in March of 2004. Both analyses found sixgills significantly more abundant in the summer months at the Seattle Aquarium’s research station. PMID:24475229

  20. Severe glomerular disease in juvenile grey snapper Lutjanus griseus L. in the Gulf of Mexico caused by the myxozoan Sphaerospora motemarini n. sp.

    PubMed Central

    Holzer, Astrid S.; Pecková, Hanka; Patra, Sneha; Brennan, Nathan P.; Yanes-Roca, Carlos; Main, Kevan L.

    2013-01-01

    In the eastern Gulf of Mexico, off the coast of Florida, grey snapper, Lutjanus griseus was found to be infected with the myxozoan parasite Sphaerospora motemarini n. sp., with high prevalence (83%) and intensity of infection occuring in age-0 fish, and with parasite levels decreasing with age (age-1 snapper 40%; age-2 snapper 0%). The morphological, molecular and phylogenetic characterisation of the myxozoan showed that it is a member of the typically marine, polysporoplasmid Sphaerospora spp. which form a subclade within the Sphaerospora sensu stricto clade of myxozoans, which is characterised by large expansion segments in their SSU rDNA sequences. Presporogonic stages of S. motemarini n. sp. were detected in the blood, using PCR. Pseudoplasmodia and spores were found to develop in the renal corpuscles of the host, causing their massive expansion. Macroscopic and histopathological changes were observed in age-0 fish and show that S. motemarini n. sp. causes severe glomerulonephritis in L. griseus leading to a compromised host condition, which makes it more susceptible to stress (catch-and-release, predators, water quality) and can result in mortalities. These results are discussed in relation to the exploitation of grey snapper populations by commercial and recreational fisheries and with the observed increased mortalities with temperature along the coast of Florida. In the future, we would like to determine prevalence and intensity of infection with S. motemarini n. sp. in juvenile L. griseus in different areas of the Gulf of Mexico in order to be able to estimate the temperature dependence of S. motemarini n. sp. proliferation and to be able to predict its distribution and severity during climatic changes in the Gulf. PMID:24533325

  1. Affinity chromatography of trypsin and related enzymes. III. Purification of Streptomyces griseus trypsin using an affinity adsorbent containing a tryptic digest of protamine as a ligand.

    PubMed

    Yokosawa, H; Hanba, T; Ishii, S

    1976-04-01

    A new, simple method has been developed for the purification of Streptomyces griseus trypsin [EC 3.4.21.4] from Pronase. Only a single operation of affinity chromatography on an agarose derivative, which was easily prepared by coupling a tryptic digest of salmine to cyanogen bromide-activated Sepharose 4B, was required. A high degree of homogeneity was demonstrated for the purified enzyme by disc electrophoresis, SDS-polyacrylamide gel electrophoresis and gel filtration, as well as by active-site titration. The behavior of a carboxypeptides B [EC 3.4.12.3]-like enzyme present in Pronase is also discussed. PMID:819428

  2. Control by A-Factor of a Metalloendopeptidase Gene Involved in Aerial Mycelium Formation in Streptomyces griseus

    PubMed Central

    Kato, Jun-ya; Suzuki, Ayano; Yamazaki, Haruka; Ohnishi, Yasuo; Horinouchi, Sueharu

    2002-01-01

    In Streptomyces griseus, A-factor (2-isocapryloyl-3R-hydroxymethyl-γ-butyrolactone) switches on aerial mycelium formation and secondary metabolite biosynthesis. An A-factor-dependent transcriptional activator, AdpA, activates multiple genes required for morphological development and secondary metabolism in a programmed manner. A region upstream of a zinc-containing metalloendopeptidase gene (sgmA) was found among the DNA fragments that had been isolated as AdpA-binding sites. The primary product of sgmA consisted of N-terminal pre, N-terminal pro, mature, and C-terminal pro regions. sgmA was transcribed in an AdpA-dependent manner, and its transcription was markedly enhanced at the timing of aerial mycelium formation. AdpA bound two sites in the region upstream of the sgmA promoter; one was at about nucleotide position −60 (A site) with respect to the transcriptional start point of sgmA, and the other was at about position −260 (B site), as determined by DNase I footprinting. Transcriptional analysis with mutated promoters showed that the A site was essential for the switching on of sgmA transcription and that the B site was necessary for the marked enhancement of transcription at the timing of aerial mycelium formation. Disruption of the chromosomal sgmA gene resulted in a delay in aerial hypha formation by half a day. SgmA is therefore suggested to be associated with the programmed morphological development of Streptomyces, in which this peptidase, perhaps together with other hydrolytic enzymes, plays a role in the degradation of proteins in substrate hyphae for reuse in aerial hypha formation. PMID:12374836

  3. Control by A-factor of a metalloendopeptidase gene involved in aerial mycelium formation in Streptomyces griseus.

    PubMed

    Kato, Jun-ya; Suzuki, Ayano; Yamazaki, Haruka; Ohnishi, Yasuo; Horinouchi, Sueharu

    2002-11-01

    In Streptomyces griseus, A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) switches on aerial mycelium formation and secondary metabolite biosynthesis. An A-factor-dependent transcriptional activator, AdpA, activates multiple genes required for morphological development and secondary metabolism in a programmed manner. A region upstream of a zinc-containing metalloendopeptidase gene (sgmA) was found among the DNA fragments that had been isolated as AdpA-binding sites. The primary product of sgmA consisted of N-terminal pre, N-terminal pro, mature, and C-terminal pro regions. sgmA was transcribed in an AdpA-dependent manner, and its transcription was markedly enhanced at the timing of aerial mycelium formation. AdpA bound two sites in the region upstream of the sgmA promoter; one was at about nucleotide position -60 (A site) with respect to the transcriptional start point of sgmA, and the other was at about position -260 (B site), as determined by DNase I footprinting. Transcriptional analysis with mutated promoters showed that the A site was essential for the switching on of sgmA transcription and that the B site was necessary for the marked enhancement of transcription at the timing of aerial mycelium formation. Disruption of the chromosomal sgmA gene resulted in a delay in aerial hypha formation by half a day. SgmA is therefore suggested to be associated with the programmed morphological development of Streptomyces, in which this peptidase, perhaps together with other hydrolytic enzymes, plays a role in the degradation of proteins in substrate hyphae for reuse in aerial hypha formation. PMID:12374836

  4. Characterization of FdmV as an Amide Synthetase for Fredericamycin A Biosynthesis in Streptomyces griseus ATCC 43944*

    PubMed Central

    Chen, Yihua; Wendt-Pienkowski, Evelyn; Ju, Jianhua; Lin, Shuangjun; Rajski, Scott R.; Shen, Ben

    2010-01-01

    Fredericamycin (FDM) A is a pentadecaketide natural product that features an amide linkage. Analysis of the fdm cluster from Streptomyces griseus ATCC 43944, however, failed to reveal genes encoding the types of amide synthetases commonly seen in natural product biosynthesis. Here, we report in vivo and in vitro characterizations of FdmV, an asparagine synthetase (AS) B-like protein, as an amide synthetase that catalyzes the amide bond formation in FDM A biosynthesis. This is supported by the findings that (i) inactivation of fdmV in vivo afforded the ΔfdmV mutant strain SB4027 that abolished FDM A and FDM E production but accumulated FDM C, a biosynthetic intermediate devoid of the characteristic amide linkage; (ii) FdmV in vitro catalyzes conversion of FDM C to FDM B, a known intermediate for FDM A biosynthesis (apparent Km = 162 ± 67 μm and kcat = 0.11 ± 0.02 min−1); and (iii) FdmV also catalyzes the amidation of FDM M-3, a structural analog of FDM C, to afford amide FDM M-6 in vitro, albeit at significantly reduced efficiency. Preliminary enzymatic studies revealed that, in addition to the common nitrogen sources (l-Gln and free amine) of class II glutamine amidotransferases (to which AS B belongs), FdmV can also utilize l-Asn as a nitrogen donor. The amide bond formation in FDM A biosynthesis is proposed to occur after C-8 hydroxylation but before the carbaspirocycle formation. PMID:20926388

  5. Seasonal Sexual Segregation by Monomorphic Sooty Shearwaters Puffinus griseus Reflects Different Reproductive Roles during the Pre-Laying Period

    PubMed Central

    Hedd, April; Montevecchi, William A.; Phillips, Richard A.; Fifield, David A.

    2014-01-01

    Tracking technology has revolutionized knowledge of seabird movements; yet, few studies have examined sex differences in distribution and behavior of small to medium-sized, sexually-monomorphic seabirds. Application of bird-borne geolocation-immersion loggers revealed seasonal segregation in the sexually-monomorphic Sooty Shearwater Puffinus griseus, mainly in the pre-laying period, when there were clear differences in reproductive roles. Shearwaters first returned to the Falkland Islands on 27 Sept±8 d; males, on average, 8 d earlier than females. Prior to egg-laying, distribution at sea, colony attendance and behaviour depended on sex. Males foraged locally over the southern Patagonian Shelf and Burdwood Bank, spending mainly single days at sea and intervening nights in the burrow. Females, who flew for more of the day during this time, foraged in more distant areas of the northern Patagonian Shelf and Argentine Basin that were deeper, warmer and relatively more productive. Attendance of females at the colony was also more variable than that of males and, overall, males were present for significantly more of the pre-laying period (38 vs. 19% of time). Sex differences were reduced following egg-laying, with males and females using similar foraging areas and making trips of similar mean duration in incubation (7.6±2.7 d) and chick-rearing (1.4±1.3 d). Congruence continued into the non-breeding period, with both sexes showing similar patterns of activity and areas of occupancy in the NW Atlantic. Thus, seasonal changes in reproductive roles influenced patterns of sexual segregation; this occurred only early in the season, when male Sooty Shearwaters foraged locally, returning regularly to the colony to defend (or maintain) the burrow or the mate, while females concentrated on building resources for egg development in distant and relatively more productive waters. PMID:24416429

  6. Pathologic findings in Western gray squirrels (Sciurus griseus) from a notoedric mange epidemic in the San Bernardino Mountains, California.

    PubMed

    Stephenson, Nicole; Swift, Pam; Villepique, Jeffrey T; Clifford, Deana L; Nyaoke, Akinyi; De la Mora, Alfonso; Moore, Janet; Foley, Janet

    2013-12-01

    Notoedric mange, caused by the contagious, burrowing mite Notoedres centrifera, has been associated with several large-scale population declines of western gray squirrels (Sciurus griseus) and has been a significant obstacle to population recovery in Washington State where the species is listed as threatened. In 2009, residents and wildlife rehabilitators in the isolated San Bernardino Mountains of southern California reported a dramatic die-off of western gray squirrels, in what had been a previously dense and robust population. Individuals were observed suffering from abnormal neurologic behaviors (ataxia and obtundation) and severe skin disease. Full necropsy of five squirrels from the epidemic showed that all had moderate to severe infestation with mange mites and severe dermatitis characterized by hyperkeratosis, acanthosis, intralesional mites, intracorneal pustules and superficial bacteria. Mites from affected squirrels were evaluated by light and electron microscopy and identified as N. centrifera based on morphologic criteria. Additionally, the internal transcribed spacer-2 region of the mite was cloned, sequenced and accessioned in GenBank. The cause for the abnormal neurologic behavior was not confirmed on post-mortem examination. However, we hypothesize that mange can cause incoordination and obtundation as a result of malnutrition and dehydration, and intense pruritis may induce abnormal or erratic behavior that could be mistaken for neurologic signs. While we have characterized the severe impact this disease can have on individual animals, more work is needed to understand the impact on squirrel populations, particularly in view of the anecdotal reports of dramatic population declines that may take decades to recover. PMID:24533345

  7. Pathologic findings in Western gray squirrels (Sciurus griseus) from a notoedric mange epidemic in the San Bernardino Mountains, California☆

    PubMed Central

    Stephenson, Nicole; Swift, Pam; Villepique, Jeffrey T.; Clifford, Deana L.; Nyaoke, Akinyi; De la Mora, Alfonso; Moore, Janet; Foley, Janet

    2013-01-01

    Notoedric mange, caused by the contagious, burrowing mite Notoedres centrifera, has been associated with several large-scale population declines of western gray squirrels (Sciurus griseus) and has been a significant obstacle to population recovery in Washington State where the species is listed as threatened. In 2009, residents and wildlife rehabilitators in the isolated San Bernardino Mountains of southern California reported a dramatic die-off of western gray squirrels, in what had been a previously dense and robust population. Individuals were observed suffering from abnormal neurologic behaviors (ataxia and obtundation) and severe skin disease. Full necropsy of five squirrels from the epidemic showed that all had moderate to severe infestation with mange mites and severe dermatitis characterized by hyperkeratosis, acanthosis, intralesional mites, intracorneal pustules and superficial bacteria. Mites from affected squirrels were evaluated by light and electron microscopy and identified as N. centrifera based on morphologic criteria. Additionally, the internal transcribed spacer-2 region of the mite was cloned, sequenced and accessioned in GenBank. The cause for the abnormal neurologic behavior was not confirmed on post-mortem examination. However, we hypothesize that mange can cause incoordination and obtundation as a result of malnutrition and dehydration, and intense pruritis may induce abnormal or erratic behavior that could be mistaken for neurologic signs. While we have characterized the severe impact this disease can have on individual animals, more work is needed to understand the impact on squirrel populations, particularly in view of the anecdotal reports of dramatic population declines that may take decades to recover. PMID:24533345

  8. Seasonal sexual segregation by monomorphic Sooty Shearwaters Puffinus griseus reflects different reproductive roles during the pre-laying period.

    PubMed

    Hedd, April; Montevecchi, William A; Phillips, Richard A; Fifield, David A

    2014-01-01

    Tracking technology has revolutionized knowledge of seabird movements; yet, few studies have examined sex differences in distribution and behavior of small to medium-sized, sexually-monomorphic seabirds. Application of bird-borne geolocation-immersion loggers revealed seasonal segregation in the sexually-monomorphic Sooty Shearwater Puffinus griseus, mainly in the pre-laying period, when there were clear differences in reproductive roles. Shearwaters first returned to the Falkland Islands on 27 Sept±8 d; males, on average, 8 d earlier than females. Prior to egg-laying, distribution at sea, colony attendance and behaviour depended on sex. Males foraged locally over the southern Patagonian Shelf and Burdwood Bank, spending mainly single days at sea and intervening nights in the burrow. Females, who flew for more of the day during this time, foraged in more distant areas of the northern Patagonian Shelf and Argentine Basin that were deeper, warmer and relatively more productive. Attendance of females at the colony was also more variable than that of males and, overall, males were present for significantly more of the pre-laying period (38 vs. 19% of time). Sex differences were reduced following egg-laying, with males and females using similar foraging areas and making trips of similar mean duration in incubation (7.6±2.7 d) and chick-rearing (1.4±1.3 d). Congruence continued into the non-breeding period, with both sexes showing similar patterns of activity and areas of occupancy in the NW Atlantic. Thus, seasonal changes in reproductive roles influenced patterns of sexual segregation; this occurred only early in the season, when male Sooty Shearwaters foraged locally, returning regularly to the colony to defend (or maintain) the burrow or the mate, while females concentrated on building resources for egg development in distant and relatively more productive waters. PMID:24416429

  9. Substrate Recognition Mechanism and Substrate-Dependent Conformational Changes of an ROK Family Glucokinase from Streptomyces griseus

    PubMed Central

    Miyazono, Ken-ichi; Tabei, Nobumitsu; Morita, Sho; Ohnishi, Yasuo; Horinouchi, Sueharu

    2012-01-01

    Carbon catabolite repression (CCR) is a widespread phenomenon in many bacteria that is defined as the repression of catabolic enzyme activities for an unfavorable carbon source by the presence of a preferable carbon source. In Streptomyces, secondary metabolite production often is negatively affected by the carbon source, indicating the involvement of CCR in secondary metabolism. Although the CCR mechanism in Streptomyces still is unclear, glucokinase is presumably a central player in CCR. SgGlkA, a glucokinase from S. griseus, belongs to the ROK family glucokinases, which have two consensus sequence motifs (1 and 2). Here, we report the crystal structures of apo-SgGlkA, SgGlkA in complex with glucose, and SgGlkA in complex with glucose and adenylyl imidodiphosphate (AMPPNP), which are the first structures of an ROK family glucokinase. SgGlkA is divided into a small α/β domain and a large α+β domain, and it forms a dimer-of-dimer tetrameric configuration. SgGlkA binds a β-anomer of glucose between the two domains, and His157 in consensus sequence 1 plays an important role in the glucose-binding mechanism and anomer specificity of SgGlkA. In the structures of SgGlkA, His157 forms an HC3-type zinc finger motif with three cysteine residues in consensus sequence 2 to bind a zinc ion, and it forms two hydrogen bonds with the C1 and C2 hydroxyls of glucose. When the three structures are compared, the structure of SgGlkA is found to be modified by the binding of substrates. The substrate-dependent conformational changes of SgGlkA may be related to the CCR mechanism in Streptomyces. PMID:22101842

  10. l-Asparaginase from Streptomyces griseus NIOT-VKMA29: optimization of process variables using factorial designs and molecular characterization of l-asparaginase gene

    PubMed Central

    Meena, Balakrishnan; Anburajan, Lawrance; Sathish, Thadikamala; Vijaya Raghavan, Rangamaran; Dharani, Gopal; Valsalan Vinithkumar, Nambali; Kirubagaran, Ramalingam

    2015-01-01

    Marine actinobacteria are known to be a rich source for novel metabolites with diverse biological activities. In this study, a potential extracellular L-asparaginase was characterised from the Streptomyces griseus NIOT-VKMA29. Box-Behnken based optimization was used to determine the culture medium components to enhance the L-asparaginase production. pH, starch, yeast extract and L-asparagine has a direct correlation for enzyme production with a maximum yield of 56.78 IU mL−1. A verification experiment was performed to validate the experiment and more than 99% validity was established. L-Asparaginase biosynthesis gene (ansA) from Streptomyces griseus NIOT-VKMA29 was heterologously expressed in Escherichia coli M15 and the enzyme production was increased threefold (123 IU mL−1) over the native strain. The ansA gene sequences reported in this study encloses several base substitutions with that of reported sequences in GenBank, resulting in altered amino acid sequences of the translated protein. PMID:26206135

  11. L-Asparaginase from Streptomyces griseus NIOT-VKMA29: optimization of process variables using factorial designs and molecular characterization of L-asparaginase gene

    NASA Astrophysics Data System (ADS)

    Meena, Balakrishnan; Anburajan, Lawrance; Sathish, Thadikamala; Vijaya Raghavan, Rangamaran; Dharani, Gopal; Valsalan Vinithkumar, Nambali; Kirubagaran, Ramalingam

    2015-07-01

    Marine actinobacteria are known to be a rich source for novel metabolites with diverse biological activities. In this study, a potential extracellular L-asparaginase was characterised from the Streptomyces griseus NIOT-VKMA29. Box-Behnken based optimization was used to determine the culture medium components to enhance the L-asparaginase production. pH, starch, yeast extract and L-asparagine has a direct correlation for enzyme production with a maximum yield of 56.78 IU mL-1. A verification experiment was performed to validate the experiment and more than 99% validity was established. L-Asparaginase biosynthesis gene (ansA) from Streptomyces griseus NIOT-VKMA29 was heterologously expressed in Escherichia coli M15 and the enzyme production was increased threefold (123 IU mL-1) over the native strain. The ansA gene sequences reported in this study encloses several base substitutions with that of reported sequences in GenBank, resulting in altered amino acid sequences of the translated protein.

  12. Karyotype morphology suggests that the Nyctibius griseus (Gmelin, 1789) carries an ancestral ZW-chromosome pair to the order Caprimulgiformes (Aves).

    PubMed

    Nieto, Leonardo Martin; Kretschmer, Rafael; Ledesma, Mario Angel; Garnero, Analía Del Valle; Gunski, Ricardo José

    2012-01-01

    Studies of karyotypes have been revealing important information on the taxonomic relationships and evolutionary patterns in various groups of birds. However, the order Caprimulgiformes is one of the least known in terms of its cytotaxonomy. So far, there are no cytogenetic data in the literature on birds belonging to 3 of 5 families of this order -Nyctibiidae, Steatornithidae and Aegothelidae. For this reason, the aim of our study was to describe the karyotype of Nyctibius griseus (Gmelin, 1789) (Aves, Nyctibiidae, Caprimulgiformes) and contribute with new data that could help to clarify the evolutionary relationships in this group. Bone marrow was cultured directly to obtain material for the chromosome study. C-banding was used to visualize the constitutive heterochromatin and Ag-NOR-banding to reveal nucleolus organizer regions. The diploid number observed was 2n=86±. Using sequential Giemsa/C-banding staining, we determined that the W chromosome was entirely C-band positive with the two most prominent markers in the interstitial and distal regions of the long arm. The nucleolus organizer regions showed a typical location in a pair of microchromosomes that exhibited Ag-NOR.The results obtained for Nyctibius griseus suggest that, of all the species studied in the references cited, it has the most ancestral sex chromosome composition of the order Caprimulgiformes. PMID:24260678

  13. Coinfection of western gray squirrel (Sciurus griseus) and other sciurid rodents with Borrelia burgdorferi sensu stricto and Anaplasma phagocytophilum in California.

    PubMed

    Nieto, Nathan C; Leonhard, Sarah; Foley, Janet E; Lane, Robert S

    2010-01-01

    Overlapping geographic distributions of tick-borne disease agents utilizing the same tick vectors are common, and coinfection of humans, domestic animals, wildlife, and ticks with both Borrelia burgdorferi and Anaplasma phagocytophilum has been frequently reported. This study was undertaken in order to evaluate the prevalence of both B. burgdorferi sensu stricto (hereinafter referred to as B. burgdorferi) and A. phagocytophilum in several species of sciurid rodents from northern California, USA. Rodents were either collected dead as road-kills or live-trapped in four state parks from 13 counties. Thirty-seven western gray squirrels (Sciurus griseus), nine nonnative eastern gray squirrels (S. carolinensis) and an eastern fox squirrel (S. niger), four Douglas squirrels (Tamiasciurus douglasii), and two northern flying squirrels (Glaucomys sabrinus) were tested by polymerase chain reaction (PCR) and serology for evidence of coinfection. Of the 14 individual S. griseus that were PCR-positive for B. burgdorferi, two (14%) also were PCR-positive for A. phagocytophilum and 11 (79%) had serologic evidence of A. phagocytophilum exposure. Two of the four Douglas squirrels were PCR positive for B. burgdorferi and seropositive to A. phagocytophilum. Evidence of coinfection with these zoonotic pathogens in western gray squirrels suggests that both bacteria may be maintained in a similar transmission cycle involving this sciurid and the western black-legged tick Ixodes pacificus, the primary bridging vector to humans in the far-western US. PMID:20090047

  14. ATP-Binding Cassette Transport System Involved in Regulation of Morphological Differentiation in Response to Glucose in Streptomyces griseus

    PubMed Central

    Seo, Jeong-Woo; Ohnishi, Yasuo; Hirata, Aiko; Horinouchi, Sueharu

    2002-01-01

    Streptomyces griseus NP4, which was derived by UV mutagenesis from strain IFO13350, showed a bald and wrinkled colony morphology in response to glucose. Mutant NP4 formed ectopic septa at intervals along substrate hyphae, and each of the compartments developed into a spore which was indistinguishable from an aerial spore in size, shape, and thickness of the spore wall and in susceptibility to lysozyme and heat. The ectopic spores of NP4 formed in liquid medium differed from “submerged spores” in lysozyme sensitivity. Shotgun cloning experiments with a library of the chromosomal DNA of the parental strain and mutant NP4 as the host gave rise to DNA fragments giving two different phenotypes; one complementing the bald phenotype of the host, and the other causing much severe wrinkled morphology in the host. Subcloning identified a gene (dasR) encoding a transcriptional repressor belonging to the GntR family that was responsible for the reversal of the bald phenotype and a gene (dasA) encoding a lipoprotein probably serving as a substrate-binding protein in an ATP-binding cassette (ABC) transport system that was responsible for the severe wrinkled morphology. These genes were adjacent but divergently encoded. Two genes, named dasB and dasC, encoding a membrane-spanning protein were present downstream of dasA, which suggested that dasRABC comprises a gene cluster for an ABC transporter, probably for sugar import. dasR was transcribed actively during vegetative growth, and dasA was transcribed just after commencement of aerial hypha formation and during sporulation, indicating that both were developmentally regulated. Transcriptional analysis and direct sequencing of dasRA in mutant NP4 suggested a defect of this mutant in the regulatory system to control the expression of these genes. Introduction of multicopies of dasA into the wild-type strain caused ectopic septation in very young substrate hyphae after only 1 day of growth and subsequent sporulation in response

  15. Control of the Streptomyces Subtilisin Inhibitor Gene by AdpA in the A-Factor Regulatory Cascade in Streptomyces griseus

    PubMed Central

    Hirano, Setsu; Kato, Jun-ya; Ohnishi, Yasuo; Horinouchi, Sueharu

    2006-01-01

    AdpA in the A-factor regulatory cascade in Streptomyces griseus activates a number of genes required for secondary metabolism and morphological differentiation, forming an AdpA regulon. The Streptomyces subtilisin inhibitor (SSI) gene, sgiA, in S. griseus was transcribed in response to AdpA, showing that sgiA is a member of the AdpA regulon. AdpA bound a single site upstream of the sgiA promoter at approximately position −70 with respect to its transcriptional start point. Mutational analysis of the AdpA-binding site showed that the AdpA-binding site was essential for transcriptional activation. Mutants in which sgiA was disrupted had higher trypsin, chymotrypsin, metalloendopeptidase, and total protease activities than the wild-type strain, which showed that SgiA modulated the activities of these extracellularly produced proteases. Because a number of genes encoding chymotrypsins, trypsins, and metalloendopeptidases, most of which are SSI-sensitive proteases, are also under the control of AdpA, the A-factor regulatory cascade was thought to play a crucial role in modulating the extracellular protease activities by triggering simultaneous production of the proteases and their inhibitor at a specific timing during growth. Mutants in which sgiA was disrupted grew normally and formed aerial hyphae and spores with the same time course as the wild-type strain. However, exogenous addition of purified SgiA to substrate mycelium grown on agar medium resulted in a delay in aerial mycelium formation, indicating that SgiA is involved in aerial hypha formation in conjunction with proteases. PMID:16923887

  16. Control of the Streptomyces Subtilisin inhibitor gene by AdpA in the A-factor regulatory cascade in Streptomyces griseus.

    PubMed

    Hirano, Setsu; Kato, Jun-ya; Ohnishi, Yasuo; Horinouchi, Sueharu

    2006-09-01

    AdpA in the A-factor regulatory cascade in Streptomyces griseus activates a number of genes required for secondary metabolism and morphological differentiation, forming an AdpA regulon. The Streptomyces subtilisin inhibitor (SSI) gene, sgiA, in S. griseus was transcribed in response to AdpA, showing that sgiA is a member of the AdpA regulon. AdpA bound a single site upstream of the sgiA promoter at approximately position -70 with respect to its transcriptional start point. Mutational analysis of the AdpA-binding site showed that the AdpA-binding site was essential for transcriptional activation. Mutants in which sgiA was disrupted had higher trypsin, chymotrypsin, metalloendopeptidase, and total protease activities than the wild-type strain, which showed that SgiA modulated the activities of these extracellularly produced proteases. Because a number of genes encoding chymotrypsins, trypsins, and metalloendopeptidases, most of which are SSI-sensitive proteases, are also under the control of AdpA, the A-factor regulatory cascade was thought to play a crucial role in modulating the extracellular protease activities by triggering simultaneous production of the proteases and their inhibitor at a specific timing during growth. Mutants in which sgiA was disrupted grew normally and formed aerial hyphae and spores with the same time course as the wild-type strain. However, exogenous addition of purified SgiA to substrate mycelium grown on agar medium resulted in a delay in aerial mycelium formation, indicating that SgiA is involved in aerial hypha formation in conjunction with proteases. PMID:16923887

  17. Three Chymotrypsin Genes Are Members of the AdpA Regulon in the A-Factor Regulatory Cascade in Streptomyces griseus

    PubMed Central

    Tomono, Ayami; Tsai, Yisan; Ohnishi, Yasuo; Horinouchi, Sueharu

    2005-01-01

    AdpA is a key transcriptional activator in the A-factor regulatory cascade in Streptomyces griseus, activating a number of genes required for secondary metabolism and morphological differentiation. Of the five chymotrypsin-type serine protease genes, sprA, sprB, and sprD were transcribed in response to AdpA, showing that these protease genes are members of the AdpA regulon. These proteases were predicted to play the same physiological role, since these protease genes were transcribed in a similar time course during growth and the matured enzymes showed high end-to-end similarity to one another. AdpA bound two sites upstream of the sprA promoter approximately at positions −375 and −50 with respect to the transcriptional start point of sprA. Mutational analysis of the AdpA-binding sites showed that both AdpA-binding sites were essential for transcriptional activation. AdpA bound a single site at position −50 in front of the sprB promoter and greatly enhanced the transcription of sprB. The AdpA-binding site at position −40 was essential for transcription of sprD, although there was an additional AdpA-binding site at position −180. Most chymotrypsin activity excreted by S. griseus was attributed to SprA and SprB, because mutant ΔsprAB, having a deletion in both sprA and sprB, lost almost all chymotrypsin activity, as did mutant ΔadpA. Even the double mutant ΔsprAB and triple mutant ΔsprABD grew normally and developed aerial hyphae and spores over the same time course as the wild-type strain. PMID:16159767

  18. Transcriptional Control by A-Factor of strR, the Pathway-Specific Transcriptional Activator for Streptomycin Biosynthesis in Streptomyces griseus

    PubMed Central

    Tomono, Ayami; Tsai, Yisan; Yamazaki, Haruka; Ohnishi, Yasuo; Horinouchi, Sueharu

    2005-01-01

    A-factor (2-isocapryloyl-3R-hydroxymethyl-γ-butyrolactone) triggers streptomycin production by inducing the transcription of strR, encoding the pathway-specific transcriptional activator, through signal transduction in the A-factor regulatory cascade in Streptomyces griseus. AdpA, one of the key transcriptional activators in the cascade, bound two upstream activation sites, approximately at nucleotide positions −270 and −50 with respect to the transcriptional start point of strR, as determined by gel mobility shift assays and DNase I footprinting. Transcriptional analysis of the strR promoter with mutated AdpA-binding sites showed that both sites were required for full transcriptional activation of strR by AdpA. Potassium permanganate footprinting showed that AdpA assisted RNA polymerase in forming an open complex at an appropriate position for transcriptional initiation of strR. Nine transcriptional units within the streptomycin biosynthesis gene cluster, including the strR-aphD operon, depended on StrR, indicating that StrR is the pathway-specific transcriptional activator for the whole gene cluster. Consistent with this, expression of strR under the control of a constitutively expressed promoter in an adpA null mutant caused the host to produce streptomycin. PMID:16077104

  19. A Single Target Is Sufficient To Account for the Biological Effects of the A-Factor Receptor Protein of Streptomyces griseus

    PubMed Central

    Kato, Jun-ya; Miyahisa, Ikuo; Mashiko, Mari; Ohnishi, Yasuo; Horinouchi, Sueharu

    2004-01-01

    In the model of the A-factor (2-isocapryloyl-3R-hydroxymethyl-γ-butyrolactone) regulatory cascade in Streptomyces griseus, A-factor binds ArpA, the A-factor receptor protein, that has bound to the adpA promoter and dissociates it from the DNA, thus inducing the transcription of adpA. AdpA switches on the transcription of a number of genes required for secondary metabolism and morphological differentiation, forming an AdpA regulon. Consistent with this model, arpA null mutants produced streptomycin and a yellow pigment in larger amounts and formed aerial hyphae from an earlier growth stage than the wild-type strain. On the other hand, mutant MK2, expressing a mutant ArpA (Trp119Ala), neither produced secondary metabolites nor formed aerial hyphae, because this A-factor-insensitive mutant ArpA always bound to and repressed the adpA promoter due to the amino acid replacement of Trp-119 with Ala. Introduction of adpA under the control of a foreign promoter into mutant MK2 restored all of the phenotypes that we could observe, which suggests that the only significant target of ArpA is adpA. In contrast to other γ-butyrolactone regulatory systems, disruption of arpA had no effect on A-factor production, indicating that ArpA does not regulate A-factor biosynthesis. Instead, A-factor production was found to be repressed by AdpA in a two-step regulatory feedback loop. PMID:15028707

  20. The proteolytic enzymes of the K-1 strain of Streptomyces griseus obtained from a commercial preparation (Pronase). Specificity and immobilization of aminopeptidase.

    PubMed

    Vosbeck, K D; Greenberg, B D; Awad, W M

    1975-05-25

    We recently described the purification of two aminopeptidases from Streptomyces griseus (Vosbeck, K.D., Chow, K.-F., and Awad, W.M., Jr. (1973) J. Biol. Chem. 248, 6329-6034). An analysis of the amino acid composition reveals very little differences in the two proteins. Each protein has alanine as the NH2-terminal residue. The aminopeptidases were treated separately with acetic anhydride; as noted in the past, the presence of glycerol is required to achieve excellent yields of acetylated active derivatives (Siegel, S., and Awad, W.M., Jr. (1973 J. Biol. Chem. 248, 3233-3240). However, in the present case much higher concentrations of glycerol (50%) are needed during acetylation to obtain derivatives with completely reacted NH2-terminal residues. The epsilon-amino groups were not completely acetylated. In contrast to the native enzymes, the acetylated derivatives show an affinity for DEAE-cellulose, a property consonant with the changes in net charge. The kinetic constants for each enzyme against L-leucine-p-nitroanilide do not change significantly after acetylation. The specificities of the two aminopeptidases were examined extensively on a semiquantitative basis. The activities are not restricted by the length of substrate chains. Each enzyme shows a preference for hydrophobic residues at the ultimate and penultimate positions. Charge residues are released a slower rates. No prolidase activity is demonstrable even at high enzyme to substrate ratios; however, NH2-terminal proline residues are released readily. D-Amino acid residues at the ultimate or penultimate position substantially reduce the rate of hydrolysis; D-leucyl-D-leucine is not hydrolyzed... PMID:805135

  1. Transcriptional Switch On of ssgA by A-Factor, Which Is Essential for Spore Septum Formation in Streptomyces griseus

    PubMed Central

    Yamazaki, Haruka; Ohnishi, Yasuo; Horinouchi, Sueharu

    2003-01-01

    A-factor (2-isocapryloyl-3R-hydroxymethyl-γ-butyrolactone) triggers morphological development and secondary metabolism in Streptomyces griseus. A transcriptional activator (AdpA) in the A-factor regulatory cascade switches on a number of genes required for both processes. AdBS11 was identified in a library of the DNA fragments that are bound by AdpA and mapped upstream of ssgA, which is essential for septum formation in aerial hyphae. Gel mobility shift assays and DNase I footprinting revealed three AdpA-binding sites at nucleotide positions about −235 (site 1), −110 (site 2), and +60 (site 3) with respect to the transcriptional start point, p1, of ssgA. ssgA had two transcriptional start points, one starting at 124 nucleotides (p1) and the other starting at 79 nucleotides (p2) upstream of the start codon of ssgA. Of the three binding sites, only sites 1 and 2 were required for transcriptional activation of p1 and p2 by AdpA. The transcriptional switch on of ssgA required the extracytoplasmic function sigma factor, σAdsA, in addition to AdpA. However, it was unlikely that σAdsA recognized the two ssgA promoters, since their −35 and −10 sequences were not similar to the promoter sequence motifs recognized by σBldN, a σAdsA homologue of Streptomyces coelicolor A3(2). An ssgA disruptant formed aerial hyphae, but did not form spores, irrespective of the carbon source of the medium, which indicated that ssgA is a member of the whi genes. Transcriptional analysis of ssfR, located just upstream of ssgA and encoding an IclR-type transcriptional regulator, suggested that no read-through from ssfR into ssgA occurred, and ssgA was transcribed in the absence of ssfR. ssgA was thus found to be controlled by AdpA and not by SsfR to a detectable extent. SsfR appeared to regulate spore septum formation independently of SsgA or through interaction with SsgA in some unknown way, because an ssfR disruptant also showed a whi phenotype. PMID:12562798

  2. Complex Structure of the DNA-binding Domain of AdpA, the Global Transcription Factor in Streptomyces griseus, and a Target Duplex DNA Reveals the Structural Basis of Its Tolerant DNA Sequence Specificity*

    PubMed Central

    Yao, Ming Dong; Ohtsuka, Jun; Nagata, Koji; Miyazono, Ken-ichi; Zhi, Yuehua; Ohnishi, Yasuo; Tanokura, Masaru

    2013-01-01

    AdpA serves as the global transcription factor in the A-factor regulatory cascade, controlling the secondary metabolism and morphological differentiation of the filamentous bacterium Streptomyces griseus. AdpA binds to over 500 operator regions with the consensus sequence 5′-TGGCSNGWWY-3′ (where S is G or C, W is A or T, Y is T or C, and N is any nucleotide). However, it is still obscure how AdpA can control hundreds of genes. To elucidate the structural basis of this tolerant DNA recognition by AdpA, we focused on the interaction between the DNA-binding domain of AdpA (AdpA-DBD), which consists of two helix-turn-helix motifs, and a target duplex DNA containing the consensus sequence 5′-TGGCGGGTTC-3′. The crystal structure of the AdpA-DBD-DNA complex and the mutant analysis of AdpA-DBD revealed its unique manner of DNA recognition, whereby only two arginine residues directly recognize the consensus sequence, explaining the strict recognition of G and C at positions 2 and 4, respectively, and the tolerant recognition of other positions of the consensus sequence. AdpA-DBD confers tolerant DNA sequence specificity to AdpA, allowing it to control hundreds of genes as a global transcription factor. PMID:24019524

  3. Hydrochemical and isotopic properties of the Mahmutlu and Bağdatoğlu mineralized thermal springs, Krşehir, Turkey

    NASA Astrophysics Data System (ADS)

    Ünsal, N.; Afşin, M.

    1999-12-01

    The present study identifies the hydrochemical and isotopic properties of the Mahmutlu and Bağdatoğlu mineralized thermal springs in Krşehir province, a geothermal field in central Anatolia, Turkey. Based on these properties, a hydrogeological regime is proposed in order to explain the Mahmutlu-Bağdatoğlu geothermal system. The relation between the concentrations of the environmental stable isotopes deuterium and oxygen-18 in the water is similar to the relationship in global meteoric water, indicating that the water is of meteoric origin. Evaluation of the geochemical characteristics of the water reveals that these two thermal springs belong to the same hydrogeological system. The hydrogeological system comprises a fractured limestone member of the Çevirme Formation and the Kervansaray Formation as reservoir rocks, and the Delicermak Formation as an overlying aquitard. The waters of the Mahmutlu and Bağdatoğlu springs are mainly of the Na-Cl-SO4 type that originate from the Pohrenk evaporite. The thermal waters are undersaturated with respect to calcite, dolomite, halite, and gypsum. The δ18O and δ2H contents indicate a δ18O shift in the Mahmutlu and Bağdatoğlu waters. The temperature range of the two reservoirs is estimated to be 98-158 °C, on the basis of Na+K+Ca and SiO2 geothermometers. RésuméCette étude présente les caractéristiques chimiques et isotopiques des sources thermales minéralisées de Mahmutlu et de Bağdatoğlu, dans la province de Krşehir, un champ géothermal d'Anatolie centrale (Turquie). Un fonctionnement hydrogéologique est proposéà partir de ces caractéristiques, permettant d'expliquer le système géothermal de Mahmatlu-Bağdatoğlu. La relation entre les teneurs en deutérium et celles en oxygène-18 des eaux est semblable à celle des eaux météoriques mondiales, ce qui indique que l'eau est d'origine météorique. Les caractéristiques géochimiques des eaux de ces deux sources montrent qu'elles appartiennent au

  4. Feeding Behavior of Subadult Sixgill Sharks (Hexanchus griseus) at a Bait Station.

    PubMed

    McNeil, Bryan; Lowry, Dayv; Larson, Shawn; Griffing, Denise

    2016-01-01

    This is the first in-situ study of feeding behaviors exhibited by bluntnose sixgill sharks. Bait was placed beneath the Seattle Aquarium pier situated on the waterfront in Elliott Bay, Puget Sound, Washington at 20m of water depth. Cameras and lights were placed around the bait box to record sixgill shark presence and behavior while feeding. Analysis of feeding behavior revealed that sixgills utilize a bite comparable to many other elasmobranchs and aquatic vertebrates, have the ability to protrude their upper jaw, change their feeding behavior based on the situation, and employ sawing and lateral tearing during manipulation. The versatility of their feeding mechanism and the ability of sixgills to change their capture and food manipulation behaviors may have contributed to the species' worldwide distribution and evolutionary success. PMID:27243237

  5. Feeding Behavior of Subadult Sixgill Sharks (Hexanchus griseus) at a Bait Station

    PubMed Central

    McNeil, Bryan; Lowry, Dayv; Larson, Shawn; Griffing, Denise

    2016-01-01

    This is the first in-situ study of feeding behaviors exhibited by bluntnose sixgill sharks. Bait was placed beneath the Seattle Aquarium pier situated on the waterfront in Elliott Bay, Puget Sound, Washington at 20m of water depth. Cameras and lights were placed around the bait box to record sixgill shark presence and behavior while feeding. Analysis of feeding behavior revealed that sixgills utilize a bite comparable to many other elasmobranchs and aquatic vertebrates, have the ability to protrude their upper jaw, change their feeding behavior based on the situation, and employ sawing and lateral tearing during manipulation. The versatility of their feeding mechanism and the ability of sixgills to change their capture and food manipulation behaviors may have contributed to the species’ worldwide distribution and evolutionary success. PMID:27243237

  6. Proteolytic enzymes of the K-1 strain of Streptomyces griseus obtained from a commercial preparation (Pronase). Purification and characterization of the carboxypeptidase.

    PubMed

    Seber, J F; Toomey, T P; Powell, J T; Brew, K; Awad, W M

    1976-01-10

    We described earlier the facilitated purifications of the trypsin and aminopeptidase components present in Pronase (Vosbeck, K. D., Chow, K. -F., and Awad, W. M., Jr. (1973) J. Biol. Chem. 248, 6029-6034). A partially resolved protein mixture left over after one of the steps in that procedure was passed through a Sephadex G-75 column. By this means, a component with carboxypeptidase activity was separated from associated serine endopeptidases. Further purification of this exopeptidase to apparent homogeneity was acheived by refiltration through the same Sephadex column and by CM-cellulose chromatography. A single protein band was observed after acrylamide gel electrophoresis; analysis by sedimentation equilibrium using the meniscus depletion method gave a molecular weight of 30,300. This enzyme demonstrates activity against Nalpha-benzyloxycarbonylglycyl-L-leucine and hippuryl-D,L-phenyllactate; no activity was found against Nalpha-acetyl-L-tyrosine ethyl ester, Nalpha-benzoyl-D,L-arginine-p-nitroanilide, or L-leuckne-p-nitroanilide. The maximum activity lies between pH values of 7 and 8; the enzyme is stable between pH values of 6 and 10. At room temperature 1,10-phenanthroline inactivates the enzyme completely whereas EDTA has no effect. Of the many cations tested, only Co2+, Ni2+, or Zn2+ restores activity to the 1,10-phenanthroline-treated enzyme; Co2+ provided 3 times the native activity. The metal in the native protein was found to be zinc. These findings are similar to those recorded with bovine pancreatic carboxypeptidase A, and suggest the possibility that the present enzyme may ge genetically related to the mammalian protein, as in previously noted examples of homology of three Pronase endopeptidases to pancreatic serine enzymes. PMID:399

  7. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (South Florida): Gray, lane, mutton, and yellowtail snappers. [Lutjanus griseus; Lutjanus synagris; Lutjanus analis; Ocyurus chrysurus

    SciTech Connect

    Bortone, S.A.; Williams, J.L.

    1986-06-01

    These four snapper species have similar morphologies as well as life history and environmental requirements. With some exceptions they are restricted to tropical and subtropical coastal areas of the western Atlantic. Adults often associate with coral reef and other hard-bottom communities. Juveniles and pre-adults usually inhabit shallow, inshore areas and are often found in seagrass beds. Reproduction usually takes place offshore in the warmer months of the year. Fecundity is positively related to female body size, but there is substantial variation both within and among the species. Juveniles obtain adult body proportions at about 50 mm SL. Approximate total maximum lengths of adults are 900 mm for gray snapper, 446 mm for lane snapper, and 750 mm for mutton and yellowtail snappers. Otoliths are the most preferred body part used to determine age. Most snappers attain sexual maturity after 3 to 5 years at a size range of 180 to 350 mm FL. Males mature at a smaller size than females. Recent commercial catches of gray and lane snappers have been increasing, whereas mutton and yellowtail snappers show no clear trends. Sport fishing probably has a substantial impact on the stocks of all four species. All four snappers feed predominantly on small benthic fishes and crustaceans, but yellowtail snapper feed on more pelagic animals. Upper water temperature tolerance limits are 27.2 to 32.5/sup 0/C and lower limits are 11 to 14/sup 0/C.

  8. Projecting Range Limits with Coupled Thermal Tolerance - Climate Change Models: An Example Based on Gray Snapper (Lutjanus griseus) along the U.S. East Coast

    PubMed Central

    Hare, Jonathan A.; Wuenschel, Mark J.; Kimball, Matthew E.

    2012-01-01

    We couple a species range limit hypothesis with the output of an ensemble of general circulation models to project the poleward range limit of gray snapper. Using laboratory-derived thermal limits and statistical downscaling from IPCC AR4 general circulation models, we project that gray snapper will shift northwards; the magnitude of this shift is dependent on the magnitude of climate change. We also evaluate the uncertainty in our projection and find that statistical uncertainty associated with the experimentally-derived thermal limits is the largest contributor (∼ 65%) to overall quantified uncertainty. This finding argues for more experimental work aimed at understanding and parameterizing the effects of climate change and variability on marine species. PMID:23284974

  9. Laminar and cytoarchitectonic features of the cerebral cortex in the Risso's dolphin (Grampus griseus), striped dolphin (Stenella coeruleoalba), and bottlenose dolphin (Tursiops truncatus).

    PubMed

    Furutani, Rui

    2008-09-01

    The present investigation carried out Nissl, Klüver-Barrera, and Golgi studies of the cerebral cortex in three distinct genera of oceanic dolphins (Risso's dolphin, striped dolphin and bottlenose dolphin) to identify and classify cortical laminar and cytoarchitectonic structures in four distinct functional areas, including primary motor (M1), primary sensory (S1), primary visual (V1), and primary auditory (A1) cortices. The laminar and cytoarchitectonic organization of each of these cortical areas was similar among the three dolphin species. M1 was visualized as five-layer structure that included the molecular layer (layer I), external granular layer (layer II), external pyramidal layer (layer III), internal pyramidal layer (layer V), and fusiform layer (layer VI). The internal granular layer was absent. The cetacean sensory-related cortical areas S1, V1, and A1 were also found to have a five-layer organization comprising layers I, II, III, V and VI. In particular, A1 was characterized by the broadest layer I, layer II and developed band of pyramidal neurons in layers III (sublayers IIIa, IIIb and IIIc) and V. The patch organization consisting of the layer IIIb-pyramidal neurons was detected in the S1 and V1, but not in A1. The laminar patterns of V1 and S1 were similar, but the cytoarchitectonic structures of the two areas were different. V1 was characterized by a broader layer II than that of S1, and also contained the specialized pyramidal and multipolar stellate neurons in layers III and V. PMID:18625031

  10. Longitudinal HIV Risk Behavior among the Drug Abuse Treatment Outcome Studies (DATOS) Adult Sample

    ERIC Educational Resources Information Center

    Murphy, Debra A.; Brecht, Mary-Lynn; Herbeck, Diane; Evans, Elizabeth; Huang, David; Hser, Yih-Ing

    2008-01-01

    Longitudinal trajectories for HIV risk were examined over 5 years following treatment among 1,393 patients who participated in the nationwide Drug Abuse Treatment Outcome Studies. Both injection drug use and sexual risk behavior declined over time, with most of the decline occurring between intake and the first-year follow-up. However, results of…

  11. Prospective Risk Factors and Treatment Outcomes among Adolescents in DATOS-A.

    ERIC Educational Resources Information Center

    Galaif, Elisha R.; Hser, Yih-Ing; Grella, Christine E.; Joshi, Vandana

    2001-01-01

    Relationships between risk factors and outcomes were examined for Drug Abuse Treatment Outcome Studies for Adolescents participants. For outpatient drug-free participants, drug use severity predicted less treatment retention; family drug involvement predicted more alcohol use after treatment. For residential participants, family drug involvement…

  12. Faridah bt. Dato Talib v. Mohd. Habibullah bin Mahmood [14 October 1989].

    PubMed

    1989-01-01

    The Malaysian court held that a Muslim wife could sue her Muslim husband for damages arising from assault and battery. It rejected the husband's argument that the suit must be adjudicated in a religious court because it was related to marriage, a topic for Muslims handled exclusively by religious courts. It concluded that assault and battery were not marital matters but criminal law matters. Moreover, it ruled for the same reason that the suit was not precluded by the Married Women Ordinance 1957, which prohibits a wife from suing her husband in tort, except for the protection or security of her property. PMID:12344524

  13. Búsqueda de Sitios para CTA: Análisis de Datos Satelitales

    NASA Astrophysics Data System (ADS)

    Suárez, A. E.; Medina, M. C.; Romero, G. E.

    The CTA Consortium has decided to implement a systematic search for sites for the Observatory. This search will be made in two different steps. The first one consists of a general determination of the possible sites on the basis of some very basic selection criteria, such as geographic latitude, altitude and extension of the flat area needed. For those sites passing these criteria, a more intensive characterization should be made, using available satellite data, together with existing ground or air-based measurements. In this work we compare the behavior of different sites analyzing the aerosol content and the total precipitable water vapor, measured by MODIS instrument. FULL TEXT IN SPANISH

  14. Clasificación de asterismos utilizando datos astrométricos

    NASA Astrophysics Data System (ADS)

    de Biasi, M. S.; Orellana, R. B.

    Based on accurate positions and proper motion data up to faint magnitudes, we have studied the regions of twenty three objects known in the literature as asterisms. A parametric method was applied to confirm the nature of these objects. The following objects have been classified: Alessi 11, Alessi 17, Brosch 1, Collinder 21, Dol-Dzim 1, Dolidze 31, Dolidze 43, Dolidze 50, Dolidze 51, NGC 272, NGC2063, NGC 2413, NGC 2664, NGC 5155, NGC 5284, NGC 6222, NGC 6360, NGC 6447, NGC 6476, NGC 6480, NGC 6605, NGC 6659, NGC 6728. FULL TEXT IN SPANISH

  15. Datos Historicos de Puerto Rico (Historical Facts on Puerto Rico). Preliminary Edition.

    ERIC Educational Resources Information Center

    Chicago Board of Education, IL. Dept. of Curriculum.

    A volume of information about Puerto Rican history and culture is designed for use by teachers in the bilingual education program of the Chicago public schools to support cultural awareness among native Spanish-speaking students. Six chapters outline important information concerning: the history of Puerto Rico, some aspects of the life of the…

  16. La Asociación OB Bochum7 combinando datos IR y ópticos

    NASA Astrophysics Data System (ADS)

    Corti, M. A.; Bosch, G. L.; Niemela, V. S.

    We present the results of an analysis of IR data in the region of the galactic OB association Bo7, obtained from the archives of the IRAS satellite mission and the 2MASS survey. Bo7 is located at the end of Perseus spiral arm. Distances of possible members of the Bo7 association were determined calculating the absorption from the E(V-K) colour excess. These members had been previously selected according to their UBV colours and spectra. The distance values obtained with IR excess have a smaller error than those obtained considering the E(B-V) excess. An extended interstellar dust cloud (detected in IRAS maps) is found to be probably associated with the members of Bo7. Two IRAS point sources observed in the region have characteristics of star formation sites. One of these point sources has been observed in CS(2-1) by Bronfman et al. (1996), who determined a value of (LSR) velocity of 44 km/s, close to the velocity of stars in Bo7 (Corti et al. 2003). A group of main sequence O - B0.5 stars appear near the location of the aforementioned IRAS point source, suggesting sequential star formation in the Bo7 region.

  17. Diseno y desarrollo de una base de datos bibliograficos (Design and Development of a Bibliographic Database).

    ERIC Educational Resources Information Center

    Mattenella, L. E.; Velazco, J. W.

    1992-01-01

    This article briefly describes the development of bibliographic retrieval systems in the Instituto de Beneficio di Minerales (IN BE MI) in Salta, Argentina, using the Mini-micro CDS/ISIS software developed by Unesco. (LRW)

  18. NIDA-Drug Addiction Treatment Outcome Study (DATOS) Relapse as a Function of Spirituality/Religiosity

    PubMed Central

    Schoenthaler, Stephen J.; Blum, Kenneth; Braverman, Eric R.; Giordano, John; Thompson, Ben; Oscar-Berman, Marlene; Badgaiyan, Rajendra D.; Madigan, Margaret A.; Dushaj, Kristina; Li, Mona; Demotrovics, Zsolt; Waite, Roger L.; Gold, Mark S.

    2015-01-01

    Background The connection between religion/spirituality and deviance, like substance abuse, was first made by Durkheim who defined socially expected behaviors as norms. He explained that deviance is due in large part to their absence (called anomie), and concluded that spirituality lowers deviance by preserving norms and social bonds. Impairments in brain reward circuitry, as observed in Reward Deficiency Syndrome (RDS), may also result in deviance and as such we wondered if stronger belief in spirituality practice and religious belief could lower relapse from drugs of abuse. Methods The NIDA Drug Addiction Treatment Outcome Study data set was used to examine post hoc relapse rates among 2,947 clients who were interviewed at 12 months after intake broken down by five spirituality measures. Results Our main findings strongly indicate, that those with low spirituality have higher relapse rates and those with high spirituality have higher remission rates with crack use being the sole exception. We found significant differences in terms of cocaine, heroin, alcohol, and marijuana relapse as a function of strength of religious beliefs (x2 = 15.18, p = 0.028; logistic regression = 10.65, p = 0.006); frequency of attending religious services (x2 = 40.78, p < 0.0005; logistic regression = 30.45, p < 0.0005); frequency of reading religious books (x2 = 27.190, p < 0.0005; logistic regression = 17.31, p < 0.0005); frequency of watching religious programs (x2 = 19.02, p = 0.002; logistic regression = ns); and frequency of meditation/prayer (x2 = 11.33, p = 0.045; logistic regression = 9.650, p = 0.002). Across the five measures of spirituality, the spiritual participants reported between 7% and 21% less alcohol, cocaine, heroin, and marijuana use than the non-spiritual subjects. However, the crack users who reported that religion was not important reported significantly less crack use than the spiritual participants. The strongest association between remission and spirituality involves attending religious services weekly, the one marker of the five that involves the highest social interaction/social bonding consistent with Durkheim’s social bond theory. Conclusions Stronger spiritual/religious beliefs and practices are directly associated with remission from abused drugs except crack. Much like the value of having a sponsor, for clients who abuse drugs, regular spiritual practice, particularly weekly attendance at the religious services of their choice is associated with significantly higher remission. These results demonstrate the clinically significant role of spirituality and the social bonds it creates in drug treatment programs. PMID:26052556

  19. Funciones de partición atómicas: Fuentes confiables de datos

    NASA Astrophysics Data System (ADS)

    Merlo, D. C.; Milone, L. A.

    Se llevó a cabo una revisión minuciosa del cálculo de funciones de partición atómicas de átomos livianos, en estados neutro y una vez ionizados, partiendo del Hidrógeno y llegando al Sodio, incluyendo también al K I y el Ca II. Al respecto, se realizó una investigación exhaustiva de referencias bibliográficas existentes hasta el presente, las cuales fueron cotejadas con cálculos propios llevados a cabo mediante el procedimiento de depresión del contínuo (0.001 a 0.5 eV). Nuestros resultados muestran un muy buen acuerdo con las expresiones interpolatorias de Traving et al (1966), al presente, la referencia más completa en cuanto a especies atómicas consideradas. Puntualizamos, además, ciertas deficiencias de estas relaciones de ajuste para decrementos del potencial de ionización altos (Δ χ >= 0.5) eV).

  20. Consideraciones acerca del método de los arcos de reducción de datos VLBI astrométricos

    NASA Astrophysics Data System (ADS)

    de Biasi, M. S.; Arias, E. F.

    Con el propósito de construir un marco de referencia cuasi-inercial, desarrollamos un sistema de coordenadas inercial introduciendo un nuevo observable: el arco entre un par de radiofuentes. Este método proveerá una mejor herramienta para el análisis y reducción de observaciones VLBI. También conducirá a una solución en donde se determinarán independientemente los parámetros astrométricos y geodésicos. En este trabajo analizamos el caso ideal de observaciones simultáneas de un par de radiofuentes y el caso más realista de observaciones cuasisimultáneas.

  1. Extracción de conocimiento en bases de datos astronómicas mediante redes de neuronas artificiales: aplicaciones en la misión Gaia

    NASA Astrophysics Data System (ADS)

    Fustes Villadóniga, Diego

    2014-02-01

    In the so-called IT era, the capabilities of data acquisition systems have increased to such an extent that it has become difficult to store all the information they produce, and analyse it. This explosion of data has recently appeared in the field of Astronomy, where an increasing number of objects are being observed on a regular basis. An example of this is the upcoming Gaia mission, which will pick up multiple properties of a billion stars, whose information will have a volume of approximately a petabyte. The analysis of a similar amount of information inevitably requires the development of new data analysis methods to extract all the knowledge it contains. This thesis is devoted to the development of data analysis methods to be integrated in the Gaia pipeline, such that knowledge can be extracted from the data collected by the mission. In order to analyze the data from the Gaia mission, the European Space Agency organized the Data Processing and Analysis Consortium (DPAC) which is composed of hundreds of scientists and engineers. DPAC is divided into eight Coordination Units (CUs). This thesis is dedicated to algorithm development in CU8, which is responsible for source classification and astrophysical parameters (AP) estimation. Methods based on Artificial Neural Networks (ANNs) are developed to perform the tasks related to two different work packages in CU8: the GSP-Spec package (GWP-823), and the OA package (GWP-836). The GSP-Spec package is responsible for estimating stellar APs by means of the Radial Velocity Spectrograph (RVS) spectrum. This work presents the development of one of the GSP-Spec modules, which is based on the application of feed-forward ANNs. A methodology is described, based on the optimization of genetic algorithms and aimed at obtaining an optimal set of configuration parameters for the ANN in each case, depending on the signal to noise ratio (SNR) in the RVS spectrum and on the type of star to parameterize. Furthermore, in order to improve the AP estimates, wavelet signal processing techniques, applied to the RVS spectrum, are studied. Despite the effectiveness shown by ANNs in estimating APs, in principle they lack the ability to provide an uncertainty value on these estimates, making it impossible to determine their reliability. Because of this, a new architecture for the ANN is presented in which the inputs and outputs are reversed, so that the ANN estimates the RVS spectrum from the APs. Such an architecture is called Generative ANN (GANN) and is applied to the AP estimation of a set of simulated RVS spectra for the Gaia mission, where it is more effective than the conventional ANN model, in the case of faint stars with low SNR. Finally, the GANN can be applied for obtaining the posterior probability of each of the APs according to the RVS spectrum, allowing for their more complete analysis. Given the nature of the Gaia mission, which is the first astronomical mission that will observe, in an unbiased way, the entire sky up to magnitude 20, a large number of outliers are expected. The OA package in CU8 handles the processing of this type of objects, which are defined as those that could not be reliably classified by the methods in the upstream classification packages. OA methods are based on the unsupervised learning of all outliers. Such learning has two parts: clustering and dimensionality reduction. The Self-Organizing Map (SOM) algorithm is selected as a basis for this learning. Its effectiveness is demonstrated when it is applied, with an optimal configuration, to the Gaia simulations. Furthermore, the algorithm is applied to real outliers from the SDSS catalog. Since a subsequent identification of the clusters obtained by the SOM is necessary, two different methods of identification are applied. The first method is based on the similarity between the SOM prototypes and the Gaia simulations, and the second method is based on the recovery of stored classifications in the SIMBAD catalog by cross-matching celestial coordinates. Thanks to the visualization of the SOM planes, and to both

  2. Astrophysics in Schools: Playing with Observational Data. (Spanish Title: Astrofísica Escolar: Jugando con Datos Observacionales.) Astrofísica Escolar: Brincando com Dados Observacionais

    NASA Astrophysics Data System (ADS)

    Navone, Hugo D.; Scancich, Miriam; Vázquez, Rubén A.

    2011-07-01

    The use of observational records in the design of teaching sequences in Astrophysics in High Schools is quite uncommon. It is also uncommon the thematic approach within the context provided by Nature of Science. Besides these shortcomings, we should also consider the lack of proposals to use the computer as a laboratory from which nature is studied. These aspects expose the existence of a disconnection between school science and scientist's science, establishing the need for simple educational projects that promote interdisciplinary dialogue between the two fields of knowledge. Based on these assumptions, this paper presents the school reformulation of the redshift-distance problem as addressed by Hubble in his diagram, and explores the main educational dimensions emerging from it. The proposal is directed not only for senior students of high school and/or early 1st year students at University level, but also for students and teachers from teacher training colleges. Practical evidence shows that this proposal is viable, mobilizes interests about issues of Astrophysics and promotes a ludic and cooperative character among students. La utilización de registros observacionales en el diseño de secuencias didácticas en Astrofísica Escolar no es algo usual en el ámbito de la escuela media. Tampoco lo es el abordaje de temáticas desde el contexto que provee Naturaleza de la Ciencia. A estas carencias se le suma la falta de propuestas que hagan intervenir a la computadora como un laboratorio desde el cual se interpela a la naturaleza. Los aspectos mencionados exponen la existencia de un desajuste entre ciencia escolar y ciencia experta estableciendo la necesidad de elaborar proyectos educativos sencillos que promuevan el diálogo interdisciplinar entre ambos campos del conocimiento. Partiendo de estos presupuestos, en este trabajo se presenta la reformulación escolar del problema abordado por Hubble -que diera lugar al diagrama que lleva su nombre- y se exploran las principales dimensiones educativas que emergen del mismo. La propuesta está destinada a alumnos del último año de nivel medio y primeros años de la universidad, y a estudiantes y profesores de Institutos de Formación Docente. Las puestas en práctica realizadas muestran que la propuesta es viable, que moviliza inquietudes en torno a temáticas de Astrofísica y que se fortalece al adquirir un carácter lúdico y cooperativo. A utilização de registros observacionais na construção de seqüências didáticas em Astrofísica Escolar não é algo usual no ensino médio. Tampouco o é uma abordagem de temáticas dentro do contexto da Natureza da Ciência. Agrega-se a estas carências a falta de propostas que estimulem a utilização do computador como um laboratório para estudar a natureza. Os aspectos mencionados expõem a existência de um desajuste entre ciência escolar e ciência avançada, estabelecendo a necessidade de elaborar projetos educativos simples que promovam o diálogo interdisciplinar entre ambos campos do conhecimento. Partindo destes pressupostos, este trabalho apresenta a reformulação escolar do problema abordado por Hubble -a relação entre redshift e distância das galáxias- e se exploram as principais dimensões educativas que emergem do mesmo. A proposta está destinada a alunos do último ano do nível médio, primeiros anos do curso superior e a estudantes e professores de Institutos de Formação Docente. As atividades práticas realizadas mostram que a proposta é viável, que mobiliza inquietudes em torno da temática e da Astrofísica e que se fortalece ao adquirir um caráter lúdico e cooperativo.

  3. Uso de los Datos de Biomonitoreo para Informar sobre la Evaluacion Infantil (American translation is: USING BIOMONITORING DATA TO INFORM EXPOSURE ASSESSMENT IN CHILDREN)

    EPA Science Inventory

    Discussing the challenges associated with estimating and interpreting toxicant exposures and health risks from biomonitoring data. This extended abstract was translated in Spanish and published in Acta Toxicologica Argentina.

  4. La Aplicacion de las Bases de Datos al Estudio Historico del Espanol (The Application of Databases to the Historical Study of Spanish).

    ERIC Educational Resources Information Center

    Nadal, Gloria Claveria; Lancis, Carlos Sanchez

    1997-01-01

    Notes that the employment of databases to the study of the history of a language is a method that allows for substantial improvement in investigative quality. Illustrates this with the example of the application of this method to two studies of the history of Spanish developed in the Language and Information Seminary of the Independent University…

  5. Extracción de conocimiento en bases de datos astronómicas mediante redes de neuronas artificiales: aplicaciones en la misión Gaia

    NASA Astrophysics Data System (ADS)

    Fustes Villadóniga, Diego

    2014-02-01

    In the so-called IT era, the capabilities of data acquisition systems have increased to such an extent that it has become difficult to store all the information they produce, and analyse it. This explosion of data has recently appeared in the field of Astronomy, where an increasing number of objects are being observed on a regular basis. An example of this is the upcoming Gaia mission, which will pick up multiple properties of a billion stars, whose information will have a volume of approximately a petabyte. The analysis of a similar amount of information inevitably requires the development of new data analysis methods to extract all the knowledge it contains. This thesis is devoted to the development of data analysis methods to be integrated in the Gaia pipeline, such that knowledge can be extracted from the data collected by the mission. In order to analyze the data from the Gaia mission, the European Space Agency organized the Data Processing and Analysis Consortium (DPAC) which is composed of hundreds of scientists and engineers. DPAC is divided into eight Coordination Units (CUs). This thesis is dedicated to algorithm development in CU8, which is responsible for source classification and astrophysical parameters (AP) estimation. Methods based on Artificial Neural Networks (ANNs) are developed to perform the tasks related to two different work packages in CU8: the GSP-Spec package (GWP-823), and the OA package (GWP-836). The GSP-Spec package is responsible for estimating stellar APs by means of the Radial Velocity Spectrograph (RVS) spectrum. This work presents the development of one of the GSP-Spec modules, which is based on the application of feed-forward ANNs. A methodology is described, based on the optimization of genetic algorithms and aimed at obtaining an optimal set of configuration parameters for the ANN in each case, depending on the signal to noise ratio (SNR) in the RVS spectrum and on the type of star to parameterize. Furthermore, in order to improve the AP estimates, wavelet signal processing techniques, applied to the RVS spectrum, are studied. Despite the effectiveness shown by ANNs in estimating APs, in principle they lack the ability to provide an uncertainty value on these estimates, making it impossible to determine their reliability. Because of this, a new architecture for the ANN is presented in which the inputs and outputs are reversed, so that the ANN estimates the RVS spectrum from the APs. Such an architecture is called Generative ANN (GANN) and is applied to the AP estimation of a set of simulated RVS spectra for the Gaia mission, where it is more effective than the conventional ANN model, in the case of faint stars with low SNR. Finally, the GANN can be applied for obtaining the posterior probability of each of the APs according to the RVS spectrum, allowing for their more complete analysis. Given the nature of the Gaia mission, which is the first astronomical mission that will observe, in an unbiased way, the entire sky up to magnitude 20, a large number of outliers are expected. The OA package in CU8 handles the processing of this type of objects, which are defined as those that could not be reliably classified by the methods in the upstream classification packages. OA methods are based on the unsupervised learning of all outliers. Such learning has two parts: clustering and dimensionality reduction. The Self-Organizing Map (SOM) algorithm is selected as a basis for this learning. Its effectiveness is demonstrated when it is applied, with an optimal configuration, to the Gaia simulations. Furthermore, the algorithm is applied to real outliers from the SDSS catalog. Since a subsequent identification of the clusters obtained by the SOM is necessary, two different methods of identification are applied. The first method is based on the similarity between the SOM prototypes and the Gaia simulations, and the second method is based on the recovery of stored classifications in the SIMBAD catalog by cross-matching celestial coordinates. Thanks to the visualization of the SOM planes, and to both methods of identification, it is possible to distinguish between valid observations and observational artifacts. Furthermore, the method allows for the selection of objects of interest for follow-up observations, in order to determine their nature.

  6. 75 FR 38078 - Incidental Taking of Marine Mammals; Taking of Marine Mammals Incidental to the Explosive Removal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ..., 2008 (73 FR 34875), and remain in effect through July 19, 2013. For detailed information on this action... bredanensis), Risso's dolphins (Grampus griseus), melon-headed whales (Peponocephala electra),...

  7. 50 CFR 216.161 - Specified activity and incidental take levels by species.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... breviceps); pilot whale (Globicephala macrorhynchus); Atlantic spotted dolphin (Stenella frontalis); spinner dolphin (S. longirostris); bottlenose dolphin (Tursiops truncatus); Risso's dolphin (Grampus griseus); rough-toothed dolphin (Steno bredanensis); common dolphin (Delphinus delphis), false killer...

  8. 50 CFR 216.180 - Specified activity.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (Dephinapterus leucas), Stenella spp., Risso's dolphin (Grampus griseus), rough-toothed dolphin (Steno bredanensis), Fraser's dolphin (Lagenodelphis hosei), northern right-whale dolphin (Lissodelphis borealis), southern right whale dolphin (Lissodelphis peronii), short-beaked common dolphin (Delphius delphis),...

  9. 50 CFR 216.161 - Specified activity and incidental take levels by species.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... breviceps); pilot whale (Globicephala macrorhynchus); Atlantic spotted dolphin (Stenella frontalis); spinner dolphin (S. longirostris); bottlenose dolphin (Tursiops truncatus); Risso's dolphin (Grampus griseus); rough-toothed dolphin (Steno bredanensis); common dolphin (Delphinus delphis), false killer...

  10. 50 CFR 216.180 - Specified activity.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (Dephinapterus leucas), Stenella spp., Risso's dolphin (Grampus griseus), rough-toothed dolphin (Steno bredanensis), Fraser's dolphin (Lagenodelphis hosei), northern right-whale dolphin (Lissodelphis borealis), southern right whale dolphin (Lissodelphis peronii), short-beaked common dolphin (Delphius delphis),...

  11. 50 CFR 216.161 - Specified activity and incidental take levels by species.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... breviceps); pilot whale (Globicephala macrorhynchus); Atlantic spotted dolphin (Stenella frontalis); spinner dolphin (S. longirostris); bottlenose dolphin (Tursiops truncatus); Risso's dolphin (Grampus griseus); rough-toothed dolphin (Steno bredanensis); common dolphin (Delphinus delphis), false killer...

  12. Taxonomy of the genus Lycalopex (Carnivora: Canidae) in Argentina

    USGS Publications Warehouse

    Zunino, G.E.; Vaccaro, O.B.; Canevari, M.; Gardner, A.L.

    1995-01-01

    Previously treated as species of Pseudalopex, Argentine members of the genus Lycalopex (L. griseus, L. gymnocercus, and L. culpaeus) are examined to clarify the taxonomic status of each named form. Principal components analyses of 26 cranial measurements of 151 adult specimens and 11 pelage characters of 111 specimens, clearly distinguish L. culpaeus from the other two taxa. Lycalopex griseus and L. gymnocercus show clinal variation in cranial measurements and pelage characters. Qualitative cranial characters, used as diagnostic for L. griseus and L. gymnocercus, revealed great nongeographic variation. We conclude that L. griseus and L. gymnocercus are conspecific, and should be known as L. gymnocercus. Therefore, we recognize only two species of the genus Lycalopex (L. culpaeus and L. gymnocercus) in Argentina. We also use this opportunity to review synonymies of the recognized species of Lycalopex.

  13. Investigation of trophic level and niche partitioning of 7 cetacean species by stable isotopes, and cadmium and arsenic tissue concentrations in the western Pacific Ocean.

    PubMed

    Liu, J-Y; Chou, L-S; Chen, M-H

    2015-04-15

    A total of 24 stranded or bycatch cetaceans, including Balaenoptera omurai, Lagenodelphis hosei, Kogia sima, Stenella attenuata, Grampus griseus, Neophocaena phocaenoides, and Sousa chinensis, were collected from 2001 to 2011 in Taiwan. Using the muscular δ(13)C and δ(15)N data, three ecological groups were identified as the oceanic baleen whale, the neritic, and the coastal toothed whale groups, coinciding with their taxonomy, feeding habits and geographical distribution. A horizontal inshore to offshore distribution was found for the sympatric neritic toothed dolphins, G. griseus, K. sima, S. attenuata, and L. hosei in the outermost offshore waters, accompanying their growth. For the first time we identify Taiwan's Chinese white dolphin, S. chinensis, as an exclusive fish eater. Cd and As bioaccumulated in the G. griseus, L. hosei and S. attenuata increase as they grow. Prey-derived As- and Cd-induced health threats were found in L. hosei, and G. griseus. PMID:25684592

  14. 50 CFR Appendix A to Part 635 - Species Tables

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., Carcharhinus isodon C. Pelagic Sharks Blue, Prionace glauca Oceanic whitetip, Carcharhinus longimanus Porbeagle..., Hexanchus griseus Smalltail, Carcharhinus porosus Whale, Rhincodon typus White, Carcharodon carcharias E... obesus Blue shark, Prionace glauca Bluefin tuna, Thunnus thynnus Dolphin fish, Coryphaena...

  15. Interconexión de la Estación Astrofísica de Bosque Alegre y la red local de datos del Observatorio Astronómico de Córdoba

    NASA Astrophysics Data System (ADS)

    Nicotra, M. A.; Anun, S.; Montes, M.; Goldes, G.; Carranza, G.

    We describe the outlines of a project for the interconnection between the Astrophysical Station of Bosque Alegre and the wide area network of the University of Córdoba. The Astrophysical Station is located 38.55 km (23.96 milles) from the Observatory of Córdoba. This location is suitable for radio links in the range of centimeters wavelenghts. In the last years, Spread-Spectrum technology equipments has become popular. Spread-Spectrum signals, contrary to narrow band radio signals, operates within a widthband 20 to 200 times broader than the widthband of the modulated information. Signals are modulated by special spreading codes, in such a way that emulates noisy signals. These codes are known under the generic designation of pseudo-random or pseudo-noise. In addition, the wide band is correlated with a low power density in the emitted signals. Spread-Spectrum equipment links are stable, exhibits low interferences with conventional radio transmitters, and their commercial prices are remarkably lower than those for the conventional microwave devices. Data links are compliant with Ethernet protocol networks and operates with data tramsmition rates up to 4 Mbits per second. The described equipment will enable the access to full-Internet services for visitor astronomers in Bosque Alegre. Also, it will be possible fast transfer for the observational data from telescope to computers in the local area network at Córdoba. This project must be considered as the second stage of another wide purpose project, which has the main purpose in transforming the Bosque Alegre Station as a fully robotic station controlled from the computational center at the Observatory in Cordoba. The advantages of robotic telescopes has recently been the subject of several discussions. However, it is now widely accepted that an automatic station enables some important options in the use of the astronomical instruments, such us the possibility of performing parallel programs, one of which is selected accordingly to environmental conditions in the instant of the observation.

  16. 77 FR 13562 - Marine Mammals; File No. 14241

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-07

    ... INFORMATION: On December 16, 2011, notice was published in the Federal Register (76 FR 78242) that a request... following species in waters off the west coast of North America: Baird's beaked whale (Berardius bairdii), Cuvier's beaked whale (Ziphius cavirostris), Risso's dolphin (Grampus griseus), killer whale...

  17. 75 FR 29991 - Marine Mammals; receipt of application for permit amendment

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-28

    ... July 15, 2009 (74 FR 3668), authorizes the permit holder to conduct research on cetacean behavior... (Globicephala macrorhynchus), long- finned pilot whale, Risso's dolphin (Grampus griseus), and false killer..., especially Cuvier's beaked whale (Ziphius cavirostris), and large delphinids such as long-finned pilot...

  18. 75 FR 47779 - Marine Mammals; File No. 14241

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-09

    ..., notice was published in the Federal Register (75 FR 29991) that a request for an amendment to the permit... (Grampus griseus), and false killer whale (Pseudorca crassidens). The new species for the project based off... beaked whale (Mesoplodon densirostris), Cuvier's beaked whale (Ziphius cavirostris), short-finned...

  19. 50 CFR 218.181 - Permissible methods of taking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (an average of 2 annually), (ii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (iii) Bottlenose dolphin (Tursiops truncatus)—3,070 (an average of 614 annually); (iv) Atlantic spotted dolphin (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S....

  20. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  1. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  2. 50 CFR 218.112 - Permissible methods of taking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (Globicephala macrorynchus)—10 (an average of 2 annually); (H) Striped dolphin (Stenella coeruleoalba)—200 (an average of 40 annually); (I) Short-beaked common dolphin (Globicephala macrorhynchus)—6280 (an average of 1256 annually); (J) Risso's dolphin (Grampus griseus)—500 (an average of 100 annually); (K)...

  3. 50 CFR 218.112 - Permissible methods of taking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (Globicephala macrorynchus)—10 (an average of 2 annually); (H) Striped dolphin (Stenella coeruleoalba)—200 (an average of 40 annually); (I) Short-beaked common dolphin (Globicephala macrorhynchus)—6280 (an average of 1256 annually); (J) Risso's dolphin (Grampus griseus)—500 (an average of 100 annually); (K)...

  4. 50 CFR 218.181 - Permissible methods of taking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (an average of 2 annually), (ii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (iii) Bottlenose dolphin (Tursiops truncatus)—3,070 (an average of 614 annually); (iv) Atlantic spotted dolphin (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S....

  5. 50 CFR 218.181 - Permissible methods of taking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (an average of 2 annually), (ii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (iii) Bottlenose dolphin (Tursiops truncatus)—3,070 (an average of 614 annually); (iv) Atlantic spotted dolphin (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S....

  6. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  7. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  8. 50 CFR 218.102 - Permissible methods of taking.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (an average of 1,289 annually); (L) Striped dolphin (Stenella coeruleoalba)—44,290 (an average of 8,858 annually); (M) Short-beaked common dolphin (Delphinus delphis)—4,715 (an average of 943 annually); (N) Risso's dolphin (Grampus griseus)—33,865 (an average of 6,773 annually); (O) Bottlenose...

  9. 50 CFR 218.181 - Permissible methods of taking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (an average of 2 annually), (ii) Risso's dolphin (Grampus griseus)—10 (an average of 2 annually); (iii) Bottlenose dolphin (Tursiops truncatus)—3,070 (an average of 614 annually); (iv) Atlantic spotted dolphin (Stenella frontalis)—2,355 (an average of 471 annually); (v) Pantropical spotted dolphin (S....

  10. 50 CFR 218.112 - Permissible methods of taking.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (Globicephala macrorynchus)—10 (an average of 2 annually); (H) Striped dolphin (Stenella coeruleoalba)—200 (an average of 40 annually); (I) Short-beaked common dolphin (Globicephala macrorhynchus)—6280 (an average of 1256 annually); (J) Risso's dolphin (Grampus griseus)—500 (an average of 100 annually); (K)...

  11. 50 CFR 218.112 - Permissible methods of taking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... (Globicephala macrorynchus)—10 (an average of 2 annually); (H) Striped dolphin (Stenella coeruleoalba)—200 (an average of 40 annually); (I) Short-beaked common dolphin (Globicephala macrorhynchus)—6280 (an average of 1256 annually); (J) Risso's dolphin (Grampus griseus)—500 (an average of 100 annually); (K)...

  12. 76 FR 37065 - Marine Mammals; File No. 14502

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ... FR 27286) that a request for a permit to import specimens for scientific research had been submitted... from Risso's (Grampus griseus), spinner (Stenella longirostris), and spotted (S. frontalis) dolphins... muscle, blubber, and teeth samples from Risso's, spinner, and spotted dolphins and short-finned...

  13. 77 FR 12010 - Marine Mammals; File Nos. 1076-1789 and 14502

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-28

    ... (72 FR 13092), authorized the receipt, import and export of marine mammal specimens (cetaceans and... June 17, 2011 (72 FR 13092), authorized the importation of samples from Risso's (Grampus griseus..., Colorado 80234 (Kristi West, Ph.D., Principal Investigator) and Russell Fielding, Ph.D., Department...

  14. A survey of the effects of proteases and glycosidases on culture of rabbit morulae to blastocysts.

    PubMed

    Kane, M T

    1986-09-01

    The effects of a range of commercially available proteases and glycosidases on blastocyst development and hatching were examined on rabbit embryos cultured from the morula stage in a defined medium supplemented with charcoal-treated bovine serum albumin. The proteases tested were trypsin, alpha-chymotrypsin, thrombin, elastase, plasmin, papain, clostripain, collagenase, Streptomyces griseus protease and cathepsin C. The glycosidases tested were neuraminidase, alpha-mannosidase, beta-galactosidase and hyaluronidase. None of these enzymes appeared to stimulate blastocyst growth. The only enzymes which digested the embryonic investments, the zona and mucin coat, sufficiently to cause complete blastocyst hatching were trypsin and Streptomyces griseus protease at relatively low concentrations (250 ng/ml) and chymotrypsin and elastase at higher concentrations. PMID:3531506

  15. First evidence of fish larvae producing sounds

    PubMed Central

    Staaterman, Erica; Paris, Claire B.; Kough, Andrew S.

    2014-01-01

    The acoustic ecology of marine fishes has traditionally focused on adults, while overlooking the early life-history stages. Here, we document the first acoustic recordings of pre-settlement stage grey snapper larvae (Lutjanus griseus). Through a combination of in situ and unprovoked laboratory recordings, we found that L. griseus larvae are acoustically active during the night, producing ‘knock’ and ‘growl’ sounds that are spectrally and temporally similar to those of adults. While the exact function and physiological mechanisms of sound production in fish larvae are unknown, we suggest that these sounds may enable snapper larvae to maintain group cohesion at night when visual cues are reduced. PMID:25274018

  16. Organizational and mutational analysis of a complete FR-008/candicidin gene cluster encoding a structurally related polyene complex.

    PubMed

    Chen, Shi; Huang, Xi; Zhou, Xiufen; Bai, Linquan; He, Jing; Jeong, Ki Jun; Lee, Sang Yup; Deng, Zixin

    2003-11-01

    The complete gene cluster for biosynthesis of a polyene complex, FR-008, spans 137.2 kb of the genome of Streptomyces sp. FR-008 consisting of six genes for a modular PKS and 15 additional genes. The extensive similarity to the partially characterized candicidin gene cluster in Streptomyces griseus IMRU3570, especially for genes involved in mycosamine biosynthesis, prompted us to compare the compounds produced by Streptomyces sp. FR-008 and Streptomyces griseus IMRU3570, and we found that FR-008 and candicidin complex are identical. A model for biosynthesis of a set of four structurally related FR-008/candicidin compounds was proposed. Deletion of the putative regulatory genes abolished antibiotic production, while disruption of putative glycosyltransferase and GDP-ketosugar aminotransferase functionalities led to the productions of a set of nonmycosaminated aglycones and a novel polyene complex with attachment of altered sugar moiety, respectively. PMID:14652074

  17. [Production of vitamin B12 by fermentation].

    PubMed

    Oğultekin, R; Oner, M

    1985-10-01

    In this work, the methods and technology of vitamin B12 production were studied on laboratory scale. The microorganisms used for experiments were Streptomyces olivaceus IFO 3409, Streptomyces olivaceus CBS 355.53 and Streptomyces griseus CBS 161.45 which were brought from foreign countries. Vitamin B12 activity that have been obtained from fermentation experiments of each microorganisms are determined by microbiological assays using Lactobacillus leichmannii IFO 3073 (ATCC 4797) which is a test microorganism. As a result of these assays S. olivaceus IFO 3409 (2 micrograms/ml) was found as the most efficient strain were followed by S. olivaceus CBS 355.53 and S. griseus CBS 16.45 respectively. PMID:3938519

  18. The use of pronase enhances sensitivity of the PAP method in the detection of intracytoplasmic immunoglobulins.

    PubMed

    Pileri, S; Serra, L; Martinelli, G

    1980-01-01

    Application of immunocytochemistry to formalin-fixed, paraffin-embedded material tends to provide capricious results, even when employing the unlabelled antibody peroxidase-antiperoxidase (PAP) method. This study shows that treatment of tissue sections with pronase, a protease isolated from a strain of Streptomyces griseus, prior to performance of the PAP procedure greatly enhances its sensitivity. The optimum conditions for use of this enzyme in detecting intracellular immunoglobulins are given. PMID:6160845

  19. Protease-catalysed direct asymmetric Mannich reaction in organic solvent.

    PubMed

    Xue, Yang; Li, Ling-Po; He, Yan-Hong; Guan, Zhi

    2012-01-01

    We reported the first enzyme-catalysed, direct, three-component asymmetric Mannich reaction using protease type XIV from Streptomyces griseus (SGP) in acetonitrile. Yields of up to 92% with enantioselectivities of up to 88% e.e. and diastereoselectivities of up to 92:8 (syn:anti) were achieved under the optimised conditions. This enzyme's catalytic promiscuity expands the application of this biocatalyst and provides a potential alternative method for asymmetric Mannich reactions. PMID:23094136

  20. Protease-catalysed Direct Asymmetric Mannich Reaction in Organic Solvent

    PubMed Central

    Xue, Yang; Li, Ling-Po; He, Yan-Hong; Guan, Zhi

    2012-01-01

    We reported the first enzyme-catalysed, direct, three-component asymmetric Mannich reaction using protease type XIV from Streptomyces griseus (SGP) in acetonitrile. Yields of up to 92% with enantioselectivities of up to 88% e.e. and diastereoselectivities of up to 92:8 (syn:anti) were achieved under the optimised conditions. This enzyme's catalytic promiscuity expands the application of this biocatalyst and provides a potential alternative method for asymmetric Mannich reactions. PMID:23094136

  1. Protease-catalysed Direct Asymmetric Mannich Reaction in Organic Solvent

    NASA Astrophysics Data System (ADS)

    Xue, Yang; Li, Ling-Po; He, Yan-Hong; Guan, Zhi

    2012-10-01

    We reported the first enzyme-catalysed, direct, three-component asymmetric Mannich reaction using protease type XIV from Streptomyces griseus (SGP) in acetonitrile. Yields of up to 92% with enantioselectivities of up to 88% e.e. and diastereoselectivities of up to 92:8 (syn:anti) were achieved under the optimised conditions. This enzyme's catalytic promiscuity expands the application of this biocatalyst and provides a potential alternative method for asymmetric Mannich reactions.

  2. A Branch Point of Streptomyces Sulfur Amino Acid Metabolism Controls the Production of Albomycin

    PubMed Central

    Kulkarni, Aditya; Zeng, Yu; Zhou, Wei; Van Lanen, Steven; Zhang, Weiwen

    2015-01-01

    Albomycin (ABM), also known as grisein, is a sulfur-containing metabolite produced by Streptomyces griseus ATCC 700974. Genes predicted to be involved in the biosynthesis of ABM and ABM-like molecules are found in the genomes of other actinomycetes. ABM has potent antibacterial activity, and as a result, many attempts have been made to develop ABM into a drug since the last century. Although the productivity of S. griseus can be increased with random mutagenesis methods, understanding of Streptomyces sulfur amino acid (SAA) metabolism, which supplies a precursor for ABM biosynthesis, could lead to improved and stable production. We previously characterized the gene cluster (abm) in the genome-sequenced S. griseus strain and proposed that the sulfur atom of ABM is derived from either cysteine (Cys) or homocysteine (Hcy). The gene product, AbmD, appears to be an important link between primary and secondary sulfur metabolic pathways. Here, we show that propargylglycine or iron supplementation in growth media increased ABM production by significantly changing the relative concentrations of intracellular Cys and Hcy. An SAA metabolic network of S. griseus was constructed. Pathways toward increasing Hcy were shown to positively impact ABM production. The abmD gene and five genes that increased the Hcy/Cys ratio were assembled downstream of hrdBp promoter sequences and integrated into the chromosome for overexpression. The ABM titer of one engineered strain, SCAK3, in a chemically defined medium was consistently improved to levels ∼400% of the wild type. Finally, we analyzed the production and growth of SCAK3 in shake flasks for further process development. PMID:26519385

  3. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  4. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  5. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  6. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  7. 9 CFR 3.104 - Space requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...'s dolphin 1.52 5.0 Delphinapterus leucas Beluga whale 4.27 14.0 Monodon monoceros Narwhale 3.96 13.0... 18.0 Grampus griseus Risso's dolphin 3.66 12.0 Orcinus orca Killer whale 7.32 24.0 Pseudorca carassidens False killer whale 4.35 14.3 Tursiops truncatus (Atlantic) Bottlenose dolphin 2.74 9.0...

  8. A Branch Point of Streptomyces Sulfur Amino Acid Metabolism Controls the Production of Albomycin.

    PubMed

    Kulkarni, Aditya; Zeng, Yu; Zhou, Wei; Van Lanen, Steven; Zhang, Weiwen; Chen, Shawn

    2016-01-01

    Albomycin (ABM), also known as grisein, is a sulfur-containing metabolite produced by Streptomyces griseus ATCC 700974. Genes predicted to be involved in the biosynthesis of ABM and ABM-like molecules are found in the genomes of other actinomycetes. ABM has potent antibacterial activity, and as a result, many attempts have been made to develop ABM into a drug since the last century. Although the productivity of S. griseus can be increased with random mutagenesis methods, understanding of Streptomyces sulfur amino acid (SAA) metabolism, which supplies a precursor for ABM biosynthesis, could lead to improved and stable production. We previously characterized the gene cluster (abm) in the genome-sequenced S. griseus strain and proposed that the sulfur atom of ABM is derived from either cysteine (Cys) or homocysteine (Hcy). The gene product, AbmD, appears to be an important link between primary and secondary sulfur metabolic pathways. Here, we show that propargylglycine or iron supplementation in growth media increased ABM production by significantly changing the relative concentrations of intracellular Cys and Hcy. An SAA metabolic network of S. griseus was constructed. Pathways toward increasing Hcy were shown to positively impact ABM production. The abmD gene and five genes that increased the Hcy/Cys ratio were assembled downstream of hrdBp promoter sequences and integrated into the chromosome for overexpression. The ABM titer of one engineered strain, SCAK3, in a chemically defined medium was consistently improved to levels ∼400% of the wild type. Finally, we analyzed the production and growth of SCAK3 in shake flasks for further process development. PMID:26519385

  9. The chromomycin CmmA acetyltransferase: a membrane-bound enzyme as a tool for increasing structural diversity of the antitumour mithramycin.

    PubMed

    García, Beatriz; González-Sabín, Javier; Menéndez, Nuria; Braña, Alfredo F; Núñez, Luz Elena; Morís, Francisco; Salas, José A; Méndez, Carmen

    2011-03-01

    Mithramycin and chromomycin A(3) are two structurally related antitumour compounds, which differ in the glycosylation profiles and functional group substitutions of the sugars. Chromomycin contains two acetyl groups, which are incorporated during the biosynthesis by the acetyltransferase CmmA in Streptomyces griseus ssp. griseus. A bioconversion strategy using an engineered S. griseus strain generated seven novel acetylated mithramycins. The newly formed compounds were purified and characterized by MS and NMR. These new compounds differ from their parental compounds in the presence of one, two or three acetyl groups, attached at 3E, 4E and/or 4D positions. All new mithramycin analogues showed antitumour activity at micromolar of lower concentrations. Some of the compounds showed improved activities against glioblastoma or pancreas tumour cells. The CmmA acetyltransferase was located in the cell membrane and was shown to accept several acyl-CoA substrates. All these results highlight the potential of CmmA as a tool to create structural diversity in these antitumour compounds. PMID:21342468

  10. Ain't No Neuroscience Mountain High Enough: Experiences of a Neurogardener.

    PubMed

    Abdullah, Jafri Malin

    2015-01-01

    16 years have passed since the idea was mooted in 1999 by five neurosurgeons in the corridors of Hotel Perdana, Kota Bharu. They were Dato' Dr Johari Siregar Bin Adnan, Dato' Professor Dr Ahmad Zubaidi Abdul Latif , Dr Azmin Kass Bin Rosman, Dato' Dr Mohammed Saffari Bin Mohammed Haspani and Professor Dato' Dr Jafri Malin Abdullah. They initiated the beginning of the first programme in Neurosurgery in Malaysia. The rest is history. PMID:26715890

  11. Pleiotropic role of the Sco1/SenC family copper chaperone in the physiology of Streptomyces

    PubMed Central

    Fujimoto, Masahiro; Yamada, Akio; Kurosawa, Junpei; Kawata, Akihiro; Beppu, Teruhiko; Takano, Hideaki; Ueda, Kenji

    2012-01-01

    Summary Antibiotic production and cell differentiation in Streptomyces is stimulated by micromolar levels of Cu2+. Here, we knocked out the Sco1/SenC family copper chaperone (ScoC) encoded in the conserved gene cluster ‘sco’ (the S treptomycescopper utilization) in Streptomyces coelicolor A3(2) and S. griseus. It is known that the Sco1/SenC family incorporates Cu2+ into the active centre of cytochrome oxidase (cox). The knockout caused a marked delay in antibiotic production and aerial mycelium formation on solid medium, temporal pH decline in glucose‐containing liquid medium, and significant reduction of cox activity in S. coelicolor. The scoC mutant produced two‐ to threefold higher cellular mass of the wild type exhibiting a marked cox activity in liquid medium supplied with 10 µM CuSO4, suggesting that ScoC is involved in not only the construction but also the deactivation of cox. The scoC mutant was defective in the monoamine oxidase activity responsible for cell aggregation and sedimentation. These features were similarly observed with regard to the scoC mutant of S. griseus. The scoC mutant of S. griseus was also defective in the extracellular activity oxidizing N,N′‐dimethyl‐p‐phenylenediamine sulfate. Addition of 10 µM CuSO4 repressed the activity of the conserved promoter preceding scoA and caused phenylalanine auxotrophy in some Streptomyces spp. probably because of the repression of pheA; pheA encodes prephenate dehydratase, which is located at the 3′ terminus of the putative operon structure. Overall, the evidence indicates that Sco is crucial for the utilization of copper under a low‐copper condition and for the activation of the multiple Cu2+‐containing oxidases that play divergent roles in the complex physiology of Streptomyces. PMID:22117562

  12. Secretion of Elastinolytic Enzymes and Their Propeptides by Pseudomonas aeruginosa

    PubMed Central

    Braun, Peter; de Groot, Arjan; Bitter, Wilbert; Tommassen, Jan

    1998-01-01

    Elastase of Pseudomonas aeruginosa is synthesized as a preproenzyme. The signal sequence is cleaved off during transport across the inner membrane and, in the periplasm, proelastase is further processed. We demonstrate that the propeptide and the mature elastase are both secreted but that the propeptide is degraded extracellularly. In addition, reduction of the extracellular proteolytic activity led to the accumulation of unprocessed forms of LasA and LasD in the extracellular medium, which shows that these enzymes are secreted in association with their propeptides. Furthermore, a hitherto undefined protein with homology to a Streptomyces griseus aminopeptidase accumulated under these conditions. PMID:9642203

  13. Secretion of elastinolytic enzymes and their propeptides by Pseudomonas aeruginosa.

    PubMed

    Braun, P; de Groot, A; Bitter, W; Tommassen, J

    1998-07-01

    Elastase of Pseudomonas aeruginosa is synthesized as a preproenzyme. The signal sequence is cleaved off during transport across the inner membrane and, in the periplasm, proelastase is further processed. We demonstrate that the propeptide and the mature elastase are both secreted but that the propeptide is degraded extracellularly. In addition, reduction of the extracellular proteolytic activity led to the accumulation of unprocessed forms of LasA and LasD in the extracellular medium, which shows that these enzymes are secreted in association with their propeptides. Furthermore, a hitherto undefined protein with homology to a Streptomyces griseus aminopeptidase accumulated under these conditions. PMID:9642203

  14. Phylogenetic revision of Minyomerus Horn, 1876 sec. Jansen & Franz, 2015 (Coleoptera, Curculionidae) using taxonomic concept annotations and alignments.

    PubMed

    Jansen, M Andrew; Franz, Nico M

    2015-01-01

    This contribution adopts the taxonomic concept annotation and alignment approach. Accordingly, and where indicated, previous and newly inferred meanings of taxonomic names are individuated according to one specific source. Articulations among these concepts and pairwise, logically consistent alignments of original and revisionary classifications are also provided, in addition to conventional nomenclatural provenance information. A phylogenetic revision of the broad-nosed weevil genera Minyomerus Horn, 1876 sec. O'Brien & Wibmer (1982), and Piscatopus Sleeper, 1960 sec. O'Brien & Wibmer (1982) (Curculionidae [non-focal]: Entiminae [non-focal]: Tanymecini [non-focal]) is presented. Prior to this study, Minyomerus sec. O'Brien & Wibmer (1982) contained seven species, whereas the monotypic Piscatopus sec. O'Brien & Wibmer (1982) was comprised solely of Piscatopus griseus Sleeper, 1960 sec. O'Brien & Wibmer (1982). We thoroughly redescribe these recognized species-level entities and furthermore describe ten species as new to science: Minyomerus bulbifrons sec. Jansen & Franz (2015) (henceforth: [JF2015]), sp. n., Minyomerus aeriballux [JF2015], sp. n., Minyomerus cracens [JF2015], sp. n., Minyomerus gravivultus [JF2015], sp. n., Minyomerus imberbus [JF2015], sp. n., Minyomerus reburrus [JF2015], sp. n., Minyomerus politus [JF2015], sp. n., Minyomerus puticulatus [JF2015], sp. n., Minyomerus rutellirostris [JF2015], sp. n., and Minyomerus trisetosus [JF2015], sp. n. A cladistic analysis using 46 morphological characters of 22 terminal taxa (5/17 outgroup/ingroup) yielded a single most-parsimonious cladogram (L = 82, CI = 65, RI = 82). The analysis strongly supports the monophyly of Minyomerus [JF2015] with eight unreversed synapomorphies, and places Piscatopus griseus sec. O'Brien & Wibmer (1982) within the genus as sister to Minyomerus rutellirostris [JF2015]. Accordingly, Piscatopus sec. Sleeper (1960), syn. n. is changed to junior synonymy of Minyomerus [JF2015], and

  15. Agnonistic behavior in short-billed dowitchers feeding on a patchy resource

    USGS Publications Warehouse

    Mallory, E.P.; Schneider, D.C.

    1979-01-01

    In this paper we describe an instance of unusual, agonistic behavior in a flock of migrant Short-billed Dowitchers (Limnodromus griseus) . We compare this behavior to that of other flocks feeding at the same time at other locations in the same estuary and then present evidence suggesting that this behavior resulted from the patchy distribution of the probable foraging resource of this flock, eggs of the horseshoe crab (Limulus polyphemus). We propose that an extremely patchy resource has increased the agonistic behavior within the flock by increasing the variation in foraging success among individuals.

  16. The use of marine reserves in evaluating the dive fishery for the warty sea cucumber, Parastichopus parvimensis in California, U.S.A

    USGS Publications Warehouse

    Schroeder, S.C.; Reed, D.C.; Kushner, D.J.; Estes, J.A.; Ono, D.S.

    2001-01-01

    In this paper we describe an instance of unusual, agonistic behavior in a flock of migrant Short-billed Dowitchers (Limnodromus griseus) . We compare this behavior to that of other flocks feeding at the same time at other locations in the same estuary and then present evidence suggesting that this behavior resulted from the patchy distribution of the probable foraging resource of this flock, eggs of the horseshoe crab (Limulus polyphemus). We propose that an extremely patchy resource has increased the agonistic behavior within the flock by increasing the variation in foraging success among individuals.

  17. Phylogenetic revision of Minyomerus Horn, 1876 sec. Jansen & Franz, 2015 (Coleoptera, Curculionidae) using taxonomic concept annotations and alignments

    PubMed Central

    Jansen, M. Andrew; Franz, Nico M.

    2015-01-01

    Abstract This contribution adopts the taxonomic concept annotation and alignment approach. Accordingly, and where indicated, previous and newly inferred meanings of taxonomic names are individuated according to one specific source. Articulations among these concepts and pairwise, logically consistent alignments of original and revisionary classifications are also provided, in addition to conventional nomenclatural provenance information. A phylogenetic revision of the broad-nosed weevil genera Minyomerus Horn, 1876 sec. O’Brien & Wibmer (1982), and Piscatopus Sleeper, 1960 sec. O’Brien & Wibmer (1982) (Curculionidae [non-focal]: Entiminae [non-focal]: Tanymecini [non-focal]) is presented. Prior to this study, Minyomerus sec. O’Brien & Wibmer (1982) contained seven species, whereas the monotypic Piscatopus sec. O’Brien & Wibmer (1982) was comprised solely of Piscatopus griseus Sleeper, 1960 sec. O’Brien & Wibmer (1982). We thoroughly redescribe these recognized species-level entities and furthermore describe ten species as new to science: Minyomerus bulbifrons sec. Jansen & Franz (2015) (henceforth: [JF2015]), sp. n., Minyomerus aeriballux [JF2015], sp. n., Minyomerus cracens [JF2015], sp. n., Minyomerus gravivultus [JF2015], sp. n., Minyomerus imberbus [JF2015], sp. n., Minyomerus reburrus [JF2015], sp. n., Minyomerus politus [JF2015], sp. n., Minyomerus puticulatus [JF2015], sp. n., Minyomerus rutellirostris [JF2015], sp. n., and Minyomerus trisetosus [JF2015], sp. n. A cladistic analysis using 46 morphological characters of 22 terminal taxa (5/17 outgroup/ingroup) yielded a single most-parsimonious cladogram (L = 82, CI = 65, RI = 82). The analysis strongly supports the monophyly of Minyomerus [JF2015] with eight unreversed synapomorphies, and places Piscatopus griseus sec. O’Brien & Wibmer (1982) within the genus as sister to Minyomerus rutellirostris [JF2015]. Accordingly, Piscatopus sec. Sleeper (1960), syn. n. is changed to junior synonymy of

  18. Holocene vegetation and climate in the Puerto Blanco Mountains, southwestern Arizona

    NASA Astrophysics Data System (ADS)

    Van Devender, Thomas R.

    1987-01-01

    Plant macrofossils from 21 pack rat ( Neotoma sp.) middens at 535-605 m from the Puerto Blanco Mountains, southwestern Arizona, provide and excellent history of vegetation and climate for the last 14, 120 yr B.P. in the Sonoran Desert. A late Wisconsin juniper-Joshua tree woodland gave way to a transitional early Holocene desertscrub with sparse Juniperus californica (California juniper) by 10,540 yr B.P. Important Sonoran Desert plants including Carnegiea gigantea (saguaro) and Encelia farinosa (brittle bush) were dominants. Riparian trees such as Acacia greggii (catclaw acacia), Prosopis velutina (velvet mesquite), and Cerdicium floridum (blue palo verde) grew on dry, south-facing slopes in a middle Holocene Sonoran desertscrub in a warm, wet summer climate with frequent winter freezes. Modern subtropical Sonoran desertscrub formed about 4000 yr B.P. as summer rainfall and winter freezes declined. Cercidium microphyllum (foothills palo verde), Sapium biloculare (Mexican jumping bean), Olneya tesota (ironwood) and Stenocereus thurberi (organ pipe cactus) became dominant as riparian trees retreated to wash habitats. The inferences of a latest Wisconsin/early Holocene summer monsoonal maximum by J. E. Kutzbach (1983), Modeling of Holocene climates. In "Late-Quaternary Environments of the United States," Vol. 2, "The Holocene" (H. E. Wright, Ed.), pp. 271-277. Univ. of Minnesota Press, Minneapolis) are not supported for the Southwest. Apparently the persistence of late Wisconsin circulation patterns offset any increases in insolation.

  19. Population Genetic Structure of a Widespread Bat-Pollinated Columnar Cactus.

    PubMed

    Bustamante, Enriquena; Búrquez, Alberto; Scheinvar, Enrique; Eguiarte, Luis Enrique

    2016-01-01

    Bats are the main pollinators and seed dispersers of Stenocereus thurberi, a xenogamous columnar cactus of northwestern Mexico and a good model to illustrate spatial dynamics of gene flow in long-lived species. Previous studies in this cactus showed differences among populations in the type and abundance of pollinators, and in the timing of flowering and fruiting. In this study we analyzed genetic variability and population differentiation among populations. We used three primers of ISSR to analyze within and among populations genetic variation from eight widely separated populations of S. thurberi in Sonora, Mexico. Sixty-six out of 99 of the ISSR bands (P = 66.7%) were polymorphic. Total heterozygosity for all populations sampled revealed high genetic diversity (Hsp = 0.207, HBT = 0.224). The AMOVA showed that most of the genetic variation was within populations (80.5%). At the species level, estimates of population differentiation, θ = 0.175 and θB = 0.194, indicated moderate gene flow among populations. The absence of a significant correlation between genetic and geographic distances indicated little isolation by geographic distance. The large genetic variation and diversity found in S. thurberi is consistent with its open reproductive system and the high mobility of bats, a major pollinator. However, small changes in number or kind of pollinators and seed dispersal agents, in the directionality of migratory routes, and/or in the timing of flowering and fruiting among populations, can critically affect gene flow dynamics. PMID:27015281

  20. Microbial populations and activities in the rhizoplane of rock-weathering desert plants. I. Root colonization and weathering of igneous rocks.

    PubMed

    Puente, M E; Bashan, Y; Li, C Y; Lebsky, V K

    2004-09-01

    Dense layers of bacteria and fungi in the rhizoplane of three species of cactus (Pachycereus pringlei, Stenocereus thurberi, Opuntia cholla) and a wild fig tree (Ficus palmeri) growing in rocks devoid of soil were revealed by bright-field and fluorescence microscopy and field emission scanning electron microscopy. These desert plants are responsible for rock weathering in an ancient lava flow at La Purisima-San Isidro and in sedimentary rock in the Sierra de La Paz, both in Baja California Sur, Mexico. The dominant bacterial groups colonizing the rhizoplane were fluorescent pseudomonads and bacilli. Seven of these bacterial species were identified by the 16S rRNA molecular method. Unidentified fungal and actimomycete species were also present. Some of the root-colonizing microorganisms fixed in vitro N(2), produced volatile and non-volatile organic acids that subsequently reduced the pH of the rock medium in which the bacteria grew, and significantly dissolved insoluble phosphates, extrusive igneous rock, marble, and limestone. The bacteria were able to release significant amounts of useful minerals, such as P, K, Mg, Mn, Fe, Cu, and Zn from the rocks and were thermo-tolerant, halo-tolerant, and drought-tolerant. The microbial community survived in the rhizoplane of cacti during the annual 10-month dry season. This study indicates that rhizoplane bacteria on cacti roots in rock may be involved in chemical weathering in hot, subtropical deserts. PMID:15375735

  1. CO{sub 2} exchange environmental productivity indices, and productivity of agaves and cacti under current and elevated atmospheric CO{sub 2} concentrations. Final report

    SciTech Connect

    Nobel, P.S.

    1994-12-31

    The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net C0{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.

  2. CO{sub 2} exchange, environmental productivity indices, and productivity of Agaves and Cacti under current and elevated atmospheric CO{sub 2} concentrations. Terminal report

    SciTech Connect

    1995-06-01

    The research described in the proposal investigated net CO{sub 2} uptake and biomass accumulation for an extremely productive CAM plant, the prickly pear cactus Opuntia ficus-indica, under conditions of elevated CO{sub 2} concentrations for relatively long periods. The influences of soil water status, air temperature, and the photosynthetic photon flux (PPF) on net CO{sub 2} uptake over 24-h periods were evaluated to enable predictions to be made based on an Environmental Productivity Index (EPI). Specifically, EPI predicts the fraction of maximal daily net CO{sub 2} uptake based on prevailing environmental conditions. It is the product of indices for temperature, soil water, and intercepted PPF, each of which range from 0.00 when that index factor completely inhibits net CO{sub 2} uptake to 1.00 when no limitation occurs. For instance, the Water Index is 1.00 under wet conditions and decreases to 0.00 during prolonged drought. Although the major emphasis of the research was on net CO{sub 2} uptake and the resulting biomass production for O. ficus-indica, effects of elevated CO{sub 2} concentrations on root: shoot ratios and on the activities of the two carboxylating enzymes were also investigated. Moreover, experiments were also done on other CAM plants, including Agave deserti, Agave salmiana, and Hylocereus undatus, and Stenocereus queretaroensis.

  3. Population Genetic Structure of a Widespread Bat-Pollinated Columnar Cactus

    PubMed Central

    Bustamante, Enriquena; Búrquez, Alberto; Scheinvar, Enrique; Eguiarte, Luis Enrique

    2016-01-01

    Bats are the main pollinators and seed dispersers of Stenocereus thurberi, a xenogamous columnar cactus of northwestern Mexico and a good model to illustrate spatial dynamics of gene flow in long-lived species. Previous studies in this cactus showed differences among populations in the type and abundance of pollinators, and in the timing of flowering and fruiting. In this study we analyzed genetic variability and population differentiation among populations. We used three primers of ISSR to analyze within and among populations genetic variation from eight widely separated populations of S. thurberi in Sonora, Mexico. Sixty-six out of 99 of the ISSR bands (P = 66.7%) were polymorphic. Total heterozygosity for all populations sampled revealed high genetic diversity (Hsp = 0.207, HBT = 0.224). The AMOVA showed that most of the genetic variation was within populations (80.5%). At the species level, estimates of population differentiation, θ = 0.175 and θB = 0.194, indicated moderate gene flow among populations. The absence of a significant correlation between genetic and geographic distances indicated little isolation by geographic distance. The large genetic variation and diversity found in S. thurberi is consistent with its open reproductive system and the high mobility of bats, a major pollinator. However, small changes in number or kind of pollinators and seed dispersal agents, in the directionality of migratory routes, and/or in the timing of flowering and fruiting among populations, can critically affect gene flow dynamics. PMID:27015281

  4. Transglutaminase from Streptomyces mobaraensis is activated by an endogenous metalloprotease.

    PubMed

    Zotzel, J; Keller, P; Fuchsbauer, H-L

    2003-08-01

    Streptomyces mobaraensis secretes a Ca2+-independent transglutaminase (TGase) that is activated by removing an N-terminal peptide from a precursor protein during submerged culture in a complex medium [Pasternack, R., Dorsch, S., Otterbach, J. T., Robenek, I. R., Wolf, S. & Fuchsbauer, H.-L. (1998) Eur. J. Biochem. 257, 570-576]. However, an activating protease could not be identified, probably because of the presence of a 14-kDa protein (P14) belonging to the Streptomyces subtilisin inhibitor family. In contrast, if the microorganism was allowed to grow on a minimal medium, several soluble proteases were extracted, among them the TGase-activating protease (TAMEP). TAMEP was purified by sequential chromatography on DEAE- and Arg-Sepharose and used to determine the cleavage site of TGase. It was clearly shown that the peptide bond between Phe(-4) and Ser(-5) was hydrolyzed, indicating that at least one additional peptidase is necessary to complete TGase processing, even if TAMEP cleavage was sufficient to obtain total activity. Sequence analysis from the N-terminus of TAMEP revealed the close relationship to a zinc endo-protease from S. griseus. The S. griseus protease differs from other members of the M4 protease family, such as thermolysin, in that it may be inhibited by the Streptomyces subtilisin inhibitor. P14 likewise inhibits TAMEP in approximately equimolar concentrations, suggesting its important role in regulating TGase activity. PMID:12869197

  5. Genome-wide Distribution of AdpA, a Global Regulator for Secondary Metabolism and Morphological Differentiation in Streptomyces, Revealed the Extent and Complexity of the AdpA Regulatory Network

    PubMed Central

    Higo, Akiyoshi; Hara, Hirofumi; Horinouchi, Sueharu; Ohnishi, Yasuo

    2012-01-01

    AdpA is a global transcriptional activator triggering morphological differentiation and secondary metabolism in Streptomyces griseus. AdpA influences the expression of >1000 genes; however, the overall picture of the AdpA regulon remains obscure. Here, we took snapshots of the distribution of AdpA across the chromosome in living S. griseus cells using chromatin immunoprecipitation/chromatin affinity precipitation-seq analysis. In both liquid and solid cultures, AdpA bound to >1200 similar sites, which were located on not only in putative regulatory regions (65%), but also in regions (35%) that appeared not to affect transcription. Transcriptome analysis indicated that ∼40% of the AdpA-binding sites in putative regulatory regions were involved in gene regulation. AdpA was indicated to act as a transcriptional repressor as well as an activator. Expression profiles of AdpA-target genes were very different between liquid and solid cultures, despite their similar AdpA-binding profiles. We concluded that AdpA directly controls >500 genes in cooperation with other regulatory proteins. A comprehensive competitive gel mobility shift assay of AdpA with 304 selected AdpA-binding sites revealed several unique characteristics of the DNA-binding property of AdpA. This study provides the first experimental insight into the extent of the AdpA regulon, indicating that many genes are under the direct control of AdpA. PMID:22449632

  6. Identification and characterization of the afsR homologue regulatory gene from Streptomyces peucetius ATCC 27952.

    PubMed

    Parajuli, Niranjan; Viet, Hung Trinh; Ishida, Kenji; Tong, Hang Thi; Lee, Hei Chan; Liou, Kwangkyoung; Sohng, Jae Kyung

    2005-01-01

    We have isolated an afsR homologue, called afsR-p, through genome analysis of Streptomyces peucetius ATCC 27952. AfsR-p shares 60% sequence identity with AfsR from Streptomyces coelicolor A3 (2). afsR-p was expressed under the control of the ermE* promoter in its hosts S. peucetius, Streptomyces lividans TK 24, Streptomyces clavuligerus and Streptomyces griseus. We observed overproduction of doxorubicin (4-fold) in S. peucetius, gamma-actinorhodin (2.6-fold) in S. lividans, clavulanic acid (1.5-fold) in S. clavuligerus and streptomycin (slight) in S. griseus. Overproduction was due to expression of the gene in these strains as compared to the wild-type strains harboring the vector only. Comparative study of the expression of afsR-p revealed that regulatory networking in Streptomyces is not uniform. We speculate that phosphorylated AfsR-p becomes bound to the promoter region of afsS. The latter activates other regulatory genes, including pathway regulatory genes, and induces the production of secondary metabolites including antibiotics. We identified specific conserved amino acids and exploited them for the isolation of the partial sequence of the afsR homologue from S. clavuligerus and Streptomyces achromogens (rubradirin producer). Such findings provide additional evidence for the presence of a serine/threonine and tyrosine kinase-dependent global regulatory network in Streptomyces. PMID:15921897

  7. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae).

    PubMed

    Tchaicka, Ligia; Freitas, Thales Renato Ochotorena de; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E; Wayne, Robert K; Eizirik, Eduardo

    2016-01-01

    To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27560989

  8. Bacterial degradation of natural and synthetic rubber.

    PubMed

    Bode, H B; Kerkhoff, K; Jendrossek, D

    2001-01-01

    The degradation of natural rubber (NR), synthetic poly(cis-1,4-isoprene) (SR), and cross-linked NR (latex gloves) by Gram-positive and Gram-negative bacteria was analyzed by weight loss, gel permeation chromatography, and determination of the protein content. Weight losses of 11-18% and an increase in protein up to 850 microg/mL after incubation of Nocardia sp. DSMZ43191, Streptomyces coelicolor, Streptomyces griseus, bacterial isolate 18a, Acinetobacter calcoaceticus, and Xanthomonas sp. with latex gloves as a carbon source indicated degradation of the polymer. An increase of protein up to 1250 microg/mL was obtained upon incubation of the bacteria with SR. No or only little weight losses and no increase in the protein content were found for nondegrading control strains such as Streptomyces lividans and Streptomyces exfoliatus and for mutants of degrading strains of S. coelicolor and S. griseus, which have been identified by their inability to produce clearing zones on opaque latex agar. Measurement of the average molecular weight of synthetic rubber before and after degradation showed a time-dependent shift to lower values for the degrading strains. Diketone derivates of oligo(cis-1,4-isoprene) were identified as metabolites of rubber degradation. An oxidative degradation pathway of poly(cis-1,4-isoprene) to acetyl-coenzymeA and propionyl-coenzymeA by beta-oxidation is suggested for bacterial degradation of isoprene rubber. PMID:11749186

  9. Diversity among Streptomyces Strains Causing Potato Scab

    PubMed Central

    Doering-Saad, Christiane; Kämpfer, Peter; Manulis, Shulamit; Kritzman, Giora; Schneider, Jörg; Zakrzewska-Czerwinska, Jolanta; Schrempf, Hildgund; Barash, Isaac

    1992-01-01

    Eighty Streptomyces isolates, including 35 potato scab-inducing strains and 12 reference strains of Streptomyces scabies, were physiologically characterized by a total of 329 miniaturized tests. Overall similarities of all strains were determined by numerical taxonomy, with the unweighted average linkage (UPGMA) algorithm and simple matching (Ssm) and Jaccard (Sj) coefficients used as measures for similarity. Three cluster groups (A to C) were defined at a similarity level of 80.1% (Ssm); these groups contained 14 clusters and 24 unclustered strains defined at a similarity level of 86.5% (Ssm). Cluster group A contained strains phenotypically related to S. griseus or S. exfoliatus, whereas cluster group B contained strains which were phenotypically related to S. violaceus or S. rochei. The majority of the pathogenic isolates and reference strains were assigned to S. violaceus (57%) and S. griseus (22%). A DNA probe derived from the rRNA operon of S. coelicolor IMET 40271 was used to detect restriction fragment length polymorphisms (RELPs) among 40 pathogenic and nonpathogenic Streptomyces isolates. Southern blots revealed a high degree of diversity among the pathogenic strains tested. No significant correlation between numerical classification and RFLP grouping of Streptomyces strains could be revealed. The results obtained suggest that RFLP data are of minor importance in classification of Streptomyces species and that genes for pathogenicity determinants are spread among different Streptomyces species by mobilizable elements. Images PMID:16348823

  10. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae)

    PubMed Central

    Tchaicka, Ligia; de Freitas, Thales Renato Ochotorena; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E.; Wayne, Robert K.; Eizirik, Eduardo

    2016-01-01

    Abstract To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27560989

  11. Trophic Relationships and Habitat Preferences of Delphinids from the Southeastern Brazilian Coast Determined by Carbon and Nitrogen Stable Isotope Composition

    PubMed Central

    Bisi, Tatiana Lemos; Dorneles, Paulo Renato; Lailson-Brito, José; Lepoint, Gilles; Azevedo, Alexandre de Freitas; Flach, Leonardo; Malm, Olaf; Das, Krishna

    2013-01-01

    To investigate the foraging habitats of delphinids in southeastern Brazil, we analyzed stable carbon (δ13C) and nitrogen (δ15N) isotopes in muscle samples of the following 10 delphinid species: Sotalia guianensis, Stenella frontalis, Tursiops truncatus, Steno bredanensis, Pseudorca crassidens, Delphinus sp., Lagenodelphis hosei, Stenella attenuata, Stenella longirostris and Grampus griseus. We also compared the δ13C and δ15N values among four populations of S. guianensis. Variation in carbon isotope results from coast to ocean indicated that there was a significant decrease in δ13C values from estuarine dolphins to oceanic species. S. guianensis from Guanabara Bay had the highest mean δ13C value, while oceanic species showed significantly lower δ13C values. The highest δ15N values were observed for P. crassidens and T. truncatus, suggesting that these species occupy the highest trophic position among the delphinids studied here. The oceanic species S. attenuata, G. griseus and L. hosei had the lowest δ15N values. Stable isotope analysis showed that the three populations of S. guianensis in coastal bays had different δ13C values, but similar δ15N results. Guiana dolphins from Sepetiba and Ilha Grande bays had different foraging habitat, with specimens from Ilha Grande showing more negative δ13C values. This study provides further information on the feeding ecology of delphinids occurring in southeastern Brazil, with evidence of distinctive foraging habitats and the occupation of different ecological niches by these species in the study area. PMID:24358155

  12. Trophic relationships and habitat preferences of delphinids from the southeastern Brazilian coast determined by carbon and nitrogen stable isotope composition.

    PubMed

    Bisi, Tatiana Lemos; Dorneles, Paulo Renato; Lailson-Brito, José; Lepoint, Gilles; Azevedo, Alexandre de Freitas; Flach, Leonardo; Malm, Olaf; Das, Krishna

    2013-01-01

    To investigate the foraging habitats of delphinids in southeastern Brazil, we analyzed stable carbon (δ(13)C) and nitrogen (δ(15)N) isotopes in muscle samples of the following 10 delphinid species: Sotalia guianensis, Stenella frontalis, Tursiops truncatus, Steno bredanensis, Pseudorca crassidens, Delphinus sp., Lagenodelphis hosei, Stenella attenuata, Stenella longirostris and Grampus griseus. We also compared the δ(13)C and δ(15)N values among four populations of S. guianensis. Variation in carbon isotope results from coast to ocean indicated that there was a significant decrease in δ(13)C values from estuarine dolphins to oceanic species. S. guianensis from Guanabara Bay had the highest mean δ(13)C value, while oceanic species showed significantly lower δ(13)C values. The highest δ(15)N values were observed for P. crassidens and T. truncatus, suggesting that these species occupy the highest trophic position among the delphinids studied here. The oceanic species S. attenuata, G. griseus and L. hosei had the lowest δ(15)N values. Stable isotope analysis showed that the three populations of S. guianensis in coastal bays had different δ(13)C values, but similar δ(15)N results. Guiana dolphins from Sepetiba and Ilha Grande bays had different foraging habitat, with specimens from Ilha Grande showing more negative δ(13)C values. This study provides further information on the feeding ecology of delphinids occurring in southeastern Brazil, with evidence of distinctive foraging habitats and the occupation of different ecological niches by these species in the study area. PMID:24358155

  13. Molecular and Functional Analyses of the Gene (eshA) Encoding the 52-Kilodalton Protein of Streptomyces coelicolor A3(2) Required for Antibiotic Production

    PubMed Central

    Kawamoto, Shinichi; Watanabe, Masakatsu; Saito, Natsumi; Hesketh, Andrew; Vachalova, Katerina; Matsubara, Keiko; Ochi, Kozo

    2001-01-01

    Analysis of proteins recovered in the S100 precipitate fraction of Streptomyces griseus after ultracentrifugation led to the identification of a 52-kDa protein which is produced during the late growth phase. The gene (eshA) which codes for this protein was cloned from S. griseus, and then its homologue was cloned from Streptomyces coelicolor A3(2). The protein was deduced to be 471 amino acids in length. The protein EshA is characterized by a central region that shows homology to the eukaryotic-type cyclic nucleotide-binding domains. Significant homology was also found to MMPI in Mycobacterium leprae, a major antigenic protein to humans. The eshA gene mapped near the chromosome end and was not essential for viability, as demonstrated by gene disruption experiments, but its disruption resulted in the abolishment of an antibiotic (actinorhodin but not undecylprodigiosin) production. Aerial mycelium was produced as abundantly as by the parent strain. Expression analysis of the EshA protein by Western blotting revealed that EshA is present only in late-growth-phase cells. The eshA gene was transcribed just preceding intracellular accumulation of the EshA protein, as determined by S1 nuclease protection, indicating that EshA expression is regulated at the transcription level. The expression of EshA was unaffected by introduction of the relA mutation, which blocks ppGpp synthesis. PMID:11567001

  14. The Level of AdpA Directly Affects Expression of Developmental Genes in Streptomyces coelicolor ▿ †

    PubMed Central

    Wolański, Marcin; Donczew, Rafał; Kois-Ostrowska, Agnieszka; Masiewicz, Paweł; Jakimowicz, Dagmara; Zakrzewska-Czerwińska, Jolanta

    2011-01-01

    AdpA is a key regulator of morphological differentiation in Streptomyces. In contrast to Streptomyces griseus, relatively little is known about AdpA protein functions in Streptomyces coelicolor. Here, we report for the first time the translation accumulation profile of the S. coelicolor adpA (adpASc) gene; the level of S. coelicolor AdpA (AdpASc) increased, reaching a maximum in the early stage of aerial mycelium formation (after 36 h), and remained relatively stable for the next several hours (48 to 60 h), and then the signal intensity decreased considerably. AdpASc specifically binds the adpASc promoter region in vitro and in vivo, suggesting that its expression is autoregulated; surprisingly, in contrast to S. griseus, the protein presumably acts as a transcriptional activator. We also demonstrate a direct influence of AdpASc on the expression of several genes whose products play key roles in the differentiation of S. coelicolor: STI, a protease inhibitor; RamR, an atypical response regulator that itself activates expression of the genes for a small modified peptide that is required for aerial growth; and ClpP1, an ATP-dependent protease. The diverse influence of AdpASc protein on the expression of the analyzed genes presumably results mainly from different affinities of AdpASc protein to individual promoters. PMID:21926228

  15. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae).

    PubMed

    Tchaicka, Ligia; Freitas, Thales Renato Ochotorena de; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E; Wayne, Robert K; Eizirik, Eduardo

    2016-07-25

    To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27459260

  16. Inhibition of alcohol dehydrogenase after 2-propanol exposure in different geographic races of Drosophila mojavensis: lack of evidence for selection at the Adh-2 locus.

    PubMed

    Pfeiler, Edward; Reed, Laura K; Markow, Therese A

    2005-03-15

    High frequencies of the fast allele of alcohol dehydrogenase-2 (Adh-2F) are found in populations of Drosophila mojavensis that inhabit the Baja California peninsula (race BII) whereas the slow allele (Adh-2S) predominates at most other localities within the species' geographic range. Race BII flies utilize necrotic tissue of pitaya agria cactus (Stenocereus gummosus) which contains high levels of 2-propanol, whereas flies from most other localities utilize different cactus hosts in which 2-propanol levels are low. To test if 2-propanol acts as a selective force on Adh-2 genotype, or whether some other yet undetermined genetic factor is responsible, mature males of D. mojavensis lines derived from the Grand Canyon (race A) and Santa Catalina Island (race C), each with individuals homozygous for Adh-2F and Adh-2S, were exposed to 2-propanol for 24 h and ADH-2 specific activity was then determined on each genotype. Flies from five other localities homozygous for either the fast or slow allele also were examined. Results for all reported races of D. mojavensis were obtained. 2-propanol exposure inhibited ADH-2 specific activity in both genotypes from all localities, but inhibition was significantly less in two populations of race BII flies homozygous for Adh-2F. When F/F and S/S genotypes in flies from the same locality were compared, both genotypes showed high 2-propanol inhibition that was not statistically different, indicating that the F/F genotype alone does not provide a benefit against the inhibitory effects of 2-propanol. ADH-1 activity in female ovaries was inhibited less by 2-propanol than ADH-2. These results do not support the hypothesis that 2-propanol acts as a selective factor favoring the Adh-2F allele. PMID:15726639

  17. Genomics of Ecological Adaptation in Cactophilic Drosophila

    PubMed Central

    Guillén, Yolanda; Rius, Núria; Delprat, Alejandra; Williford, Anna; Muyas, Francesc; Puig, Marta; Casillas, Sònia; Ràmia, Miquel; Egea, Raquel; Negre, Barbara; Mir, Gisela; Camps, Jordi; Moncunill, Valentí; Ruiz-Ruano, Francisco J.; Cabrero, Josefa; de Lima, Leonardo G.; Dias, Guilherme B.; Ruiz, Jeronimo C.; Kapusta, Aurélie; Garcia-Mas, Jordi; Gut, Marta; Gut, Ivo G.; Torrents, David; Camacho, Juan P.; Kuhn, Gustavo C.S.; Feschotte, Cédric; Clark, Andrew G.; Betrán, Esther; Barbadilla, Antonio; Ruiz, Alfredo

    2015-01-01

    Cactophilic Drosophila species provide a valuable model to study gene–environment interactions and ecological adaptation. Drosophila buzzatii and Drosophila mojavensis are two cactophilic species that belong to the repleta group, but have very different geographical distributions and primary host plants. To investigate the genomic basis of ecological adaptation, we sequenced the genome and developmental transcriptome of D. buzzatii and compared its gene content with that of D. mojavensis and two other noncactophilic Drosophila species in the same subgenus. The newly sequenced D. buzzatii genome (161.5 Mb) comprises 826 scaffolds (>3 kb) and contains 13,657 annotated protein-coding genes. Using RNA sequencing data of five life-stages we found expression of 15,026 genes, 80% protein-coding genes, and 20% noncoding RNA genes. In total, we detected 1,294 genes putatively under positive selection. Interestingly, among genes under positive selection in the D. mojavensis lineage, there is an excess of genes involved in metabolism of heterocyclic compounds that are abundant in Stenocereus cacti and toxic to nonresident Drosophila species. We found 117 orphan genes in the shared D. buzzatii–D. mojavensis lineage. In addition, gene duplication analysis identified lineage-specific expanded families with functional annotations associated with proteolysis, zinc ion binding, chitin binding, sensory perception, ethanol tolerance, immunity, physiology, and reproduction. In summary, we identified genetic signatures of adaptation in the shared D. buzzatii–D. mojavensis lineage, and in the two separate D. buzzatii and D. mojavensis lineages. Many of the novel lineage-specific genomic features are promising candidates for explaining the adaptation of these species to their distinct ecological niches. PMID:25552534

  18. Effects of natural and artificial selection on survival of columnar cacti seedlings: the role of adaptation to xeric and mesic environments

    PubMed Central

    Guillén, Susana; Terrazas, Teresa; Casas, Alejandro

    2015-01-01

    Escontria chiotilla, Polaskia chichipe, and Stenocereus pruinosus are species of Mexican columnar cacti that are economically important because of their edible fruits. These species are managed by gathering fruits from the wild, silvicultural management in agroforestry systems, and cultivation in home gardens. Previous studies reported that artificial selection favored individuals that produced larger fruits, which indirectly led to the production of larger seeds and seedlings, with possible effects on survival. We hypothesized that seedlings from managed populations would be larger but more susceptible to xeric conditions than those from wild populations. We evaluated the effects of artificial and natural selection on seedling survival of the three species in wild and managed populations, which were managed with low and high intensity, respectively. We tested seedling performance in gradients of shade (0, 40, and 80%) and humidity (low and high). A GLM of seedling survival showed significant differences among species, shade, and humidity treatments, with each species having environmental requirements associated with their particular adaptations. High humidity decreased seedling survival of all species, and high solar radiation decreased survival of S. pruinosus and P. chichipe. The effect of management type was significant only in S. pruinosus. Significant differences in the initial growth of seedlings among species were detected with ANOVA. In optimal conditions, the hypocotyl and the cotyledons decreased in size and the epicotyl grew, whereas under stress, these structures remained unchanged. The optimum conditions of shade and humidity varied among species and management types. The seedlings of S. pruinosus were the largest and the most susceptible, but in all species, seedlings from managed populations were more susceptible to environmental conditions. Thus, artificial selection influenced the susceptibility of these cacti to xeric environments. PMID

  19. Determinate primary root growth as an adaptation to aridity in Cactaceae: towards an understanding of the evolution and genetic control of the trait

    PubMed Central

    Shishkova, Svetlana; Las Peñas, María Laura; Napsucialy-Mendivil, Selene; Matvienko, Marta; Kozik, Alex; Montiel, Jesús; Patiño, Anallely; Dubrovsky, Joseph G.

    2013-01-01

    Background and Aims Species of Cactaceae are well adapted to arid habitats. Determinate growth of the primary root, which involves early and complete root apical meristem (RAM) exhaustion and differentiation of cells at the root tip, has been reported for some Cactoideae species as a root adaptation to aridity. In this study, the primary root growth patterns of Cactaceae taxa from diverse habitats are classified as being determinate or indeterminate, and the molecular mechanisms underlying RAM maintenance in Cactaceae are explored. Genes that were induced in the primary root of Stenocereus gummosus before RAM exhaustion are identified. Methods Primary root growth was analysed in Cactaceae seedlings cultivated in vertically oriented Petri dishes. Differentially expressed transcripts were identified after reverse northern blots of clones from a suppression subtractive hybridization cDNA library. Key Results All species analysed from six tribes of the Cactoideae subfamily that inhabit arid and semi-arid regions exhibited determinate primary root growth. However, species from the Hylocereeae tribe, which inhabit mesic regions, exhibited mostly indeterminate primary root growth. Preliminary results suggest that seedlings of members of the Opuntioideae subfamily have mostly determinate primary root growth, whereas those of the Maihuenioideae and Pereskioideae subfamilies have mostly indeterminate primary root growth. Seven selected transcripts encoding homologues of heat stress transcription factor B4, histone deacetylase, fibrillarin, phosphoethanolamine methyltransferase, cytochrome P450 and gibberellin-regulated protein were upregulated in S. gummosus root tips during the initial growth phase. Conclusions Primary root growth in Cactoideae species matches their environment. The data imply that determinate growth of the primary root became fixed after separation of the Cactiodeae/Opuntioideae and Maihuenioideae/Pereskioideae lineages, and that the genetic regulation of

  20. Western gray squirrel (Rodentia: Sciuridae): a primary reservoir host of Borrelia burgdorferi in Californian oak woodlands?

    PubMed

    Lane, Robert S; Mun, Jeomhee; Eisen, Rebecca J; Eisen, Lars

    2005-05-01

    In California, dense woodlands have been recognized as important biotopes where humans are exposed to the nymphal stage of the western blacklegged tick, Ixodes pacificus Cooley & Kohls, the primary vector of the Lyme disease spirochete Borrelia burgdorferi sensu stricto (s.s.), in the far-western United States. To identify the principal reservoir host(s) of this spirochete, and of closely related spirochetes in the B. burgdorferi sensu lato (s.l.) complex, in dense woodlands in Mendocino County, California, approximately 50 species of birds and mammals, including wood rats and kangaroo rats, were evaluated as potential hosts for vector ticks and borreliae in 2002 and 2003. Although polymerase chain reaction (PCR) and sequencing analyses revealed that many vertebrate species had been exposed to one or more members of the B. burgdorferi s.l. spirochetal complex, only the western gray squirrel, Sciurus griseus, fulfilled the major criteria for a reservoir host of B. burgdorferi s.s. Ear-punch biopsies from eight of 10 squirrels collected from five separate woodlands were PCR-positive for B. burgdorferi s.s., 47% of I. pacificus larvae (n = 64) and 31% of nymphs (n = 49) removed from squirrels contained B. burgdorferi s.l., and the engorgement status of I. pacificus larvae was associated positively with acquisition of spirochetes. Overall, 83 and 100% of the amplicons sequenced from PCR-positive I. pacificus larvae and nymphs, respectively, were identified as B. burgdorferi s.s, Among the five remaining positive I. pacificus larvae, three contained B. bissettii and two had uncharacterized B. burgdorferi s.l. Borrelia burgdorferi s.s. was detected in one of five larvae and zero of two nymphs of the Pacific Coast tick, Dermacentor occidentalis Marx, that likewise had been removed from squirrels. The rickettsial agent of human anaplasmosis, Anaplasma phagocytophilum, was detected in the blood or ear biopsies of two squirrels and in one (1.6%) of 64 I. pacificus larvae and

  1. Kinetics of leaping primates: influence of substrate orientation and compliance.

    PubMed

    Demes, B; Jungers, W L; Gross, T S; Fleagle, J G

    1995-04-01

    Our current knowledge about the forces leapers generate and absorb is very limited and based exclusively on rigid force platform measurements. In their natural environments, however, leapers take off and land on branches and tree trunks, and these may be compliant. We evaluated the influence of substrate properties on leaping kinetics in prosimian leapers by using a combined field and laboratory approach. Tree sway and the timing of takeoffs relative to the movements of trees were documented for animals under natural conditions in Madagascar. Field data collected on three species (Indri indri, Propithecus diadema, Propithecus verreauxi) indicate that in the majority of takeoffs, the substrate sways and the animals takeoff before the elastic rebound of the substrate. This implies that force is "wasted" to deform supports. Takeoff and landing forces were measured in an experimental setting with a compliant force pole at the Duke University Primate Center. Forces were recorded for 2 Propithecus verreauxi and 3 Hapalemur griseus. Peak takeoff forces were 9.6 (P. verreauxi) and 10.3 (H. griseus) times body weight, whereas peak landing forces were 6.7 (P. verreauxi) and 8.4 (H. griseus) times body weight. As part of the impulse generated does not translate into leaping distance but is used to deform the pole, greater effort is required to reach a given target substrate, and, consequently, takeoff forces are high. The landing forces, on the other hand, are damped by the pole/substrate yield that increases the time available for deceleration. Our results contrast with previous studies of leaping forces recorded with rigid platform measuring systems that usually report higher landing than takeoff forces. We conclude that 1) Leapers generate and are exposed to exceptionally high locomotory forces. The takeoff forces are higher than the landing forces when using compliant supports, indicating that the takeoff rather than the landing may be critical in interpreting leaping

  2. Flotation of cadmium-loaded biomass.

    PubMed

    Matis, K A; Zouboulis, A I

    1994-07-01

    Biosorption of heavy metal ions such as Cd(2+) by dead biomass has been recognized as a potential alternative to existing removal technologies applied to wastewater treatment. Two bacterial strains were studied in the laboratory, streptomyces griseus and S. clavuligerus, an industrial by-product. Both washed and unwashed samples were examined. Foam flotation proposed in this work as the separation state following biosorption. Effective biomass separation was conducted in the presence of a frother, ethanol. The pH of the solution was a crucial parameter for flotation and also for metal binding. Other basic parameters of flotation examined were the initial cadmium concentration in the dilute aqueous solution and the quantity of biomass used. A study of zeta-potential measurements of the actinomycetes was carried out under the conditions used in the separation; surface tension was also measured. These provided useful information on the process. PMID:18618752

  3. Molecular characterization of a gene encoding extracellular serine protease isolated from a subtilisin inhibitor-deficient mutant of Streptomyces albogriseolus S-3253.

    PubMed Central

    Taguchi, S; Odaka, A; Watanabe, Y; Momose, H

    1995-01-01

    An extracellular serine protease produced by a mutant, M1, derived from Streptomyces albogriseolus S-3253 that no longer produces a protease inhibitor (Streptomyces subtilisin inhibitor [SSI]) was isolated. A 20-kDa protein was purified by its affinity for SSI and designated SAM-P20. The amino acid sequence of the amino-terminal region of SAM-P20 revealed high homology with the sequences of Streptomyces griseus proteases A and B, and the gene sequence confirmed the relationships. The sequence also revealed a putative amino acid signal sequence for SAM-P20 that apparently functioned to allow secretion of SAM-P20 from Escherichia coli carrying the recombinant gene. SAM-P20 produced by E. coli cells was shown to be sensitive to SSI inhibition. PMID:7887600

  4. [Structure and functions of bacterial proteinase precursors].

    PubMed

    Serkina, A V; Shevelev, A B; Chestukhina, G G

    2001-01-01

    The data on the precursors of bacterial proteases were generalized. The structure and special features of processing of the precursors of bacillary subtilisins, the alpha-lytic protease from Lysobacter enzymogenes and the related chymotrypsin-like proteases from Streptomyces griseus, and the metalloproteases from bacilli and Pseudomonas aeruginosa were discussed. The approaches to producing the precursors and the protease propeptides and to in vitro characterizing them were particularly analyzed. The following physiological functions of the propeptides within the protease precursors were considered probable: (a) inhibition of the proteases to protect the host cells from the proteolytic damage; (b) participation in the folding of the mature enzyme; and (c) providing for the protease interaction with the bacterial cell surveillance mechanisms, including protease translocation through the cell wall. PMID:11641907

  5. Purification, characterization cloning, and sequencing of metalloendopeptidase from Streptomyces septatus TH-2.

    PubMed

    Hatanaka, Tadashi; Yoshiko Uesugi, Jiro Arima; Iwabuchi, Masaki

    2005-02-15

    Streptomyces septatus TH-2 secretes a large amount of a protease when cultured on a medium containing K(2)HPO(4) and glucose. The enzyme was purified to homogeneity by a three-step procedure. This enzyme had a molecular mass of approximately 35kDa, and was particularly inhibited by EDTA and phosphoramidon. Its substrate specificity was investigated using novel fluorescence energy transfer combinatorial libraries. The protease was found to prefer Phe and Tyr at the P(1) position, a hydrophobic or basic residue at the P(2) position, and a basic or small residue at the P(3) position. Its gene was cloned and sequenced, and its deduced amino acid sequence contained an HEXXH consensus sequence for zinc binding, confirming that it encodes metalloendopeptidase. The primary structure of the enzyme showed 40 and 69% identities with that of thermolysin from Bacillus thermoproteolyticus and that of a metalloendopeptidase from Streptomyces griseus, respectively. PMID:15639229

  6. Peptide sequence information derived by pronase digestion and ammonium sulfate in-source decay matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    PubMed

    Marzilli, L A; Golden, T R; Cotter, R J; Woods, A S

    2000-11-01

    We present the use of Pronase digestion and in-source decay in the presence of ammonium sulfate as complementary techniques to confirm the amino acid sequence of a peptide. Pronase, a commercial preparation from Streptomyces griseus, is a combination of proteolytic enzymes. It produces carboxypeptidase and aminopeptidase ladders using a single Pronase digestion and represents an inexpensive, nonspecific, and fast supplement to traditional sequencing enzymes. However, N-terminal peptidase activity appears dependent on the terminal amino acid residue. We also introduce the use of saturated ammonium sulfate as an "on-slide" sample additive to promote in-source fragmentation of peptides. Use of saturated ammonium sulfate resulted in a simple way to increase peptide backbone fragmentation and essentially produced either a cn or yn ion series. Together these techniques provide useful supplements to existing methods for peptide sequence information. PMID:11073263

  7. Inhibition of metalloendopeptidases by 2-mercaptoacetyl-dipeptides.

    PubMed

    Blumberg, S; Tauber, Z

    1983-10-17

    A series of 2-mercaptoacetyl-dipeptides, a potential group of metalloendopeptidase inhibitors, has been synthesized by coupling the N-hydroxysuccinimide ester of S-acetyl-2-mercaptoacetic acid with hydrophobic dipeptide methyl ester hydrochlorides, followed by hydrolysis with NaOH in aqueous methanol and acidification with HCl. Thus, the 2-mercaptoacetyl derivatives of L-phenylalanyl-L-leucine, L-leucyl-L-phenylalanine and L-leucyl-D-phenylalanine were prepared. The first two compounds inhibit effectively thermolysin from Bacillus thermoproteolyticus and a metalloendopeptidase isolated from Streptomyces griseus, with Ki values in the micromolar range or below. The third compound inhibits the two enzymes only poorly, showing the stereospecificity of the inhibition process. These inhibitors should provide a useful tool for the study of bacterial and mammalian metalloendopeptidases (or dipeptidyl carboxypeptidases) and for the assessment of their physiological role. PMID:6413206

  8. [The effect of enzymatic treatment using proteases on properties of persistent sodium current in CA1 pyramidal neurons of rat hippocampus].

    PubMed

    Lun'ko, O O; Isaiev, D S; Maxymiuk, O P; Kryshtal', O O; Isaieva, O V

    2014-01-01

    We investigated the effect of proteases, widely used for neuron isolation in electrophysiological studies, on the amplitude and kinetic characteristics of persistent sodium current (I(NaP)) in hippocampal CA1 pyramidal neurons. Properties of I(NaP) were studied on neurons isolated by mechanical treatment (control group) and by mechanical and enzymatic treatment using pronase E (from Streptomyces griseus) or protease type XXIII (from Aspergillus oryzae). We show that in neurons isolated with pronase E kinetic of activation and density of I(NaP) was unaltered. Enzymatic treatment with protease type XXIII did not alter I(NaP) activation but result in significant decrease in I(NaP) density. Our data indicates that enzymatic treatment using pronase E for neuron isolation is preferable for investigation of I(NaP). PMID:25097934

  9. Morphologic characteristics of pulmonary macrophages in cetaceans: particular reference to pulmonary intravascular macrophages as a newly identified type.

    PubMed

    Kawashima, M; Kuwamura, M; Takeya, M; Yamate, J

    2004-11-01

    We examined the morphologic characteristics of pulmonary macrophages in 42 specimens of Odontoceti (Globicephala macrorhynchus, Grampus griseus, Tursiops truncatus, Stenella attenuata, Stenella coeruleoalba, Berardius bairdii), using light and electron microscopes as well as immunohistochemistry with SRA-E5. SRA-E5-positive alveolar macrophages and pulmonary interstitial macrophages contained graphitic soots, indicating the clearance of airborne, aspirated foreign bodies. Pulmonary intravascular macrophages (PIMs), positive with SRA-E5, were present within pulmonary capillaries, attaching to applied endothelial cells by cell junctions. They showed cytoplasmic tubular structures of micropinocytosis vermiformis and erythrophagocytosis, indicating their contributory role in the clearance of blood-borne particles. The uptake of pathogens by PIMs may be associated with the inducement of acute lung injury, especially bacterial infectious pneumonia. This study revealed for the first time the presence of PIMs in cetaceans. PMID:15557077

  10. Retinal projections in two crocodilian species, Caiman crocodilus and Crocodylus niloticus.

    PubMed

    Derobert, Y; Médina, M; Rio, J P; Ward, R; Repérant, J; Marchand, M J; Miceli, D

    1999-08-01

    The retinal projections of Caiman crocodilus and Crocodylus niloticus were investigated by means of the orthograde axonal transport of either rhodamine beta-isothiocyanate or tritiated proline. In these two species, each tracer revealed contralateral retinal projections to three hypothalamic regions (subventricular gray matter, nucleus suprachiasmaticus, and area optica hypothalami lateralis), five thalamic regions (nuclei ovalis, dorsolateralis anterior, ventrolateralis and ventrobasalis, and lateral geniculate complex, of which six subcomponents can be distinguished), six pretectal regions (nuclei posterodorsalis, lentiformis mesencephali, griseus tectalis, geniculatus pretectalis, area optica commissurae posterior and area optica pretectalis lateroventralis), six outermost layers of the optic tectum, and the nucleus opticus tegmenti. Weak ipsilateral retinal projections have been observed in two hypothalamic nuclei and in the nucleus opticus tegmenti. Comparative analysis with other data show that the contralateral retinal projections of crocodiles are considerably more reptilian than avian. Moreover, crocodiles share with birds an extremely poor contingent of ipsilateral retinal projections. PMID:10424875

  11. Shorebird diet and size selection of nereid polychaetes in South Carolina coastal diked wetlands

    USGS Publications Warehouse

    Weber, Louise M.; Haig, Susan M.

    1997-01-01

    Coastal wetlands that are diked and managed may supplement declining natural habitat for migrating shorebirds (Charadriiformes). However, data on shorebird diet in these diked wetlands are scarce. We examined shorebird diet and prey size selection in brackish diked wetlands at the Yawkey Center on South Island, South Carolina, USA. Gut contents of seven Lesser Yellowlegs (Tringa flavipes) and seven Short-billed Dowitchers (Limnodromus griseus) were examined. The most common items in gut contents were mandibles of the nereid polychaete, Laeonereis culveri, followed by insects. L. culveri eaten by Short-billed Dowitchers were significantly larger than those eaten by Lesser Yellowlegs. This difference may be related to differences in bill length and feeding tactics. We make suggestions on how to maintain high numbers of L. culveri in diked wetlands, but more research on the timing of colonization by invertebrates is needed in shorebird conservation efforts.

  12. Identification of a cryptic type III polyketide synthase (1,3,6,8-tetrahydroxynaphthalene synthase) from Streptomyces peucetius ATCC 27952.

    PubMed

    Ghimire, Gopal Prasad; Oh, Tae-Jin; Liou, Kwangkyoung; Sohng, Jae Kyung

    2008-10-31

    We identified a 1,134-bp putative type III polyketide synthase from the sequence analysis of Streptomyces peucetius ATCC 27952, named Sp-RppA, which is characterized as 1,3,6,8-tetrahydroxynaphthalene synthase and shares 33% identity with SCO1206 from S. coelicolor A3(2) and 32% identity with RppA from S. griseus. The 1,3,6,8-tetrahydroxynaphthalene synthase is known to catalyze the sequential decarboxylative condensation, intramolecular cyclization, and aromatization of an oligoketide derived from five units of malonyl-CoA to give 1,3,6,8-tetrahydroxynaphthalene, which spontaneously oxidizes to form 2,5,7-trihydroxy-1,4-naphthoquinone (flaviolin). In this study, we report the in vivo expression and in vitro synthesis of flaviolin from purified gene product (Sp-RppA). PMID:18612244

  13. Engineering Protein Allostery: 1.05 Å Resolution Structure and Enzymatic Properties of a Na[superscript +]-activated Trypsin

    SciTech Connect

    Page, Michael J.; Carrell, Christopher J.; Di Cera, Enrico

    2008-05-28

    Some trypsin-like proteases are endowed with Na{sup +}-dependent allosteric enhancement of catalytic activity, but this important mechanism has been difficult to engineer in other members of the family. Replacement of 19 amino acids in Streptomyces griseus trypsin targeting the active site and the Na{sup +}-binding site were found necessary to generate efficient Na{sup +} activation. Remarkably, this property was linked to the acquisition of a new substrate selectivity profile similar to that of factor Xa, a Na{sup -} activated protease involved in blood coagulation. The X-ray crystal structure of the mutant trypsin solved to 1.05 {angstrom} resolution defines the engineered Na{sup +} site and active site loops in unprecedented detail. The results demonstrate that trypsin can be engineered into an efficient allosteric protease, and that Na+ activation is interwoven with substrate selectivity in the trypsin scaffold.

  14. Distribution of Cd and As in organs and tissues of four marine mammal species stranded along the Italian coasts.

    PubMed

    Bellante, Antonio; Sprovieri, Mario; Buscaino, Giuseppa; Buffa, Gaspare; Di Stefano, Vincenzo; Manta, Daniela Salvagio; Barra, Marco; Filiciotto, Francesco; Bonanno, Angelo; Mazzola, Salvatore

    2012-09-01

    Concentrations of Cd and As were determined in organs and tissues (muscle, heart, kidney, lung and liver) of four cetacean species (Stenella coeruleoalba, Truncatus truncatus, Grampus griseus and Ziphius cavirostris) stranded along the Italian coasts during the period 2000-2009. Significant differences were found between Cd concentrations in the different analysed tissues. Particularly, the kidney shows the highest concentrations of Cd in all analysed specimens, followed by the liver. No systematic or statistically significant difference in As concentrations was found in the analysed tissues. Considerable differences of Cd and As values in samples from different geographical areas (Sicily Channel, Adriatic Sea and Tyrrhenian Sea) were found, with the highest values measured in samples from the Sicily Channel. This basically suggests that anthropogenic and natural sources significantly affect Cd and As content in cetaceans. PMID:22797766

  15. Kinetics of Methyl t-Butyl Ether Cometabolism at Low Concentrations by Pure Cultures of Butane-Degrading Bacteria

    PubMed Central

    Liu, Catherine Y.; Speitel, Gerald E.; Georgiou, George

    2001-01-01

    Butane-oxidizing Arthrobacter (ATCC 27778) bacteria were shown to degrade low concentrations of methyl t-butyl ether (MTBE; range, 100 to 800 μg/liter) with an apparent half-saturation concentration (Ks) of 2.14 mg/liter and a maximum substrate utilization rate (kc) of 0.43 mg/mg of total suspended solids per day. Arthrobacter bacteria demonstrated MTBE degradation activity when grown on butane but not when grown on glucose, butanol, or tryptose phosphate broth. The presence of butane, tert-butyl alcohol, or acetylene had a negative impact on the MTBE degradation rate. Neither Methylosinus trichosporium OB3b nor Streptomyces griseus was able to cometabolize MTBE. PMID:11319100

  16. Winter status of White-eyed Vireos in northeastern Louisiana

    USGS Publications Warehouse

    Somershoe, S.G.; Twedt, D.J.

    2005-01-01

    In December 2004, February 2005, and June 2005, we recaptured a White-eyed Vireo (Vireo griseus) that was banded on 19 May 2004 at the same location on the Tensas River National Wildlife Refuge, Madison Parish, LA. This is the first documented permanent resident White-eyed Vireo outside of resident populations known from Florida and southern Texas. This individual appears to be resident near the northern limit of the winter range for the species. Although White-eyed Vireos are uncommon in northeastern Louisiana during winter, we detected other White-eyed Vireos during line transect surveys and banding during winters 2003-2004 and 2004-2005. The lack of research and observation of winter birds in northern Louisiana and the secretive and inconspicuous behavior of White-eyed Vireos in winter may have led to an underestimation of abundance at the northern limits of their winter range.

  17. First record of interspecific breeding of Least Bell's Vireo and White-eyed Vireo

    USGS Publications Warehouse

    Blundell, Melissa A.; Kus, Barbara E.

    2011-01-01

    We provide the first known documentation of a male Least Bell's Vireo (Vireo bellii pusillus) breeding with a female White-eyed Vireo (V. griseus) and the first report of a White-eyed Vireo breeding in California at the San Luis Rey River, Oceanside, San Diego County. We discovered the pair building a nest on 12 May 2010. The female laid four eggs, and the pair successfully raised and fledged four nestlings. We collected DNA samples from each nestling and the female during the nestling stage and banded them with a numbered federal leg band for future identification. We obtained detailed nest measurements after fledging and monitored the territory for further nesting attempts. No additional nesting attempts were detected.

  18. Common procedures in hedgehogs, prairie dogs, exotic rodents, and companion marsupials.

    PubMed

    Johnson-Delaney, Cathy A

    2006-05-01

    Nondomesticated species are commonly being kept as companion animals. These include the African pygmy hedgehog (Atelerix albi-ventris), the North American black-tailed prairie dog (Cynomys lu-dovicianus), and exotic rodents such as the degu (Octodon degus)and duprasi or fat-tailed gerbil (Pachyuromys duprasi). Common companion marsupials include the sugar glider (Petaurus breviceps),Bennett's or Tammar (Dama) wallabies (Macropus rufogriseus rufo-griseus and Macropus eugenii, respectively), the Brazilian or South American gray short-tailed opossum (Monodelphis domestica), and the North American Virginia opossum (Didelphis virginiana). Although many of these animals are now bred domestically and are fairly docile when human-raised, they are essentially wild animals and hence have strong instincts to hide illness and pain. PMID:16759954

  19. Residency of Reef Fish During Pile Driving Within a Shallow Pierside Environment.

    PubMed

    Iafrate, Joseph D; Watwood, Stephanie L; Reyier, Eric A; Gilchrest, Matthew; Crocker, Steven E

    2016-01-01

    The potential effects of pile driving on fish populations and commercial fisheries have received significant attention given the prevalence of construction occurring in coastal habitats throughout the world. In this study, we used acoustic telemetry to assess the movement and survival of free-ranging reef fish in Port Canaveral, FL, in response to 35 days of pile driving at an existing wharf complex. The site fidelity and behavior of 15 sheepshead (Archosargus probatocephalus) and 10 gray snapper (Lutjanus griseus) were determined before, during, and after pile driving. No obvious signs of mortality or injury to tagged fish were evident from the data. There was a significant decline in the residency index for mangrove snapper at the construction wharf after pile driving compared with the baseline, although this may be influenced by natural movements of this species in the study area rather than a direct response to pile driving. PMID:26610995

  20. Chitinase activity on amorphous chitin thin films: a quartz crystal microbalance with dissipation monitoring and atomic force microscopy study.

    PubMed

    Wang, Chao; Kittle, Joshua D; Qian, Chen; Roman, Maren; Esker, Alan R

    2013-08-12

    Chitinases are widely distributed in nature and have wide-ranging pharmaceutical and biotechnological applications. This work highlights a real-time and label-free method to assay Chitinase activity via a quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM). The chitin substrate was prepared by spincoating a trimethylsilyl chitin solution onto a silica substrate, followed by regeneration to amorphous chitin (RChi). The QCM-D and AFM results clearly showed that the hydrolysis rate of RChi films increased as Chitinase (from Streptomyces griseus) concentrations increased, and the optimal temperature and pH for Chitinase activity were around 37 °C and 6-8, respectively. The Chitinase showed greater activity on chitin substrates, having a high degree of acetylation, than on chitosan substrates, having a low degree of acetylation. PMID:23822524

  1. Purification and Characterization of a Keratinolytic Serine Proteinase from Streptomyces albidoflavus

    PubMed Central

    Bressollier, Philippe; Letourneau, François; Urdaci, Maria; Verneuil, Bernard

    1999-01-01

    Streptomyces strain K1-02, which was identified as a strain of Streptomyces albidoflavus, secreted at least six extracellular proteases when it was cultured on feather meal-based medium. The major keratinolytic serine proteinase was purified to homogeneity by a two-step procedure. This enzyme had a molecular weight of 18,000 and was optimally active at pH values ranging from 6 to 9.5 and at temperatures ranging from 40 to 70°C. Its sensitivity to protease inhibitors, its specificity on synthetic substrates, and its remarkably high level of NH2-terminal sequence homology with Streptomyces griseus protease B (SGPB) showed that the new enzyme, designated SAKase, was homologous to SGPB. We tested the activity of SAKase with soluble and fibrous substrates (elastin, keratin, and type I collagen) and found that it was very specific for keratinous substrates compared to SGPB and proteinase K. PMID:10347045

  2. Divergent effects of desferrioxamine on bacterial growth and characteristics.

    PubMed

    Eto, Daisei; Watanabe, Kenta; Saeki, Hisafumi; Oinuma, Ken-ichi; Otani, Ko-ichi; Nobukuni, Megumi; Shiratori-Takano, Hatsumi; Takano, Hideaki; Beppu, Teruhiko; Ueda, Kenji

    2013-04-01

    Desferrioxamines (DF's) are siderophores produced by some groups of bacteria. Previously, we discovered that DFE, produced by Streptomyces griseus, induced divergent developmental phenotypes in various Streptomyces isolates. In this study, we isolated bacteria whose phenotype was affected by the presence of 0.1 mM DFB from soil samples, and studied their phylogenetic position via 16 S rRNA gene-based analysis. Isolates belonging to Microbacterium grew only in the presence of DFB in the medium. DFB promoted growth of some isolates, while significantly inhibiting that of other divergent bacteria. Different groups of isolates were affected, not because of growth-related changes, but because of changes in the colony morphology based on possible stimulation of motility. An isolate affiliated with Janthinobacterium was stimulated for violacein production as well as for pilus formation. The wide and divergent effects of DFB suggest that availability of siderophores significantly affect the structure of microbial community. PMID:23232933

  3. Interaction between aspergilli and streptomycetes in the soil of potted indoor plants: a preliminary report (contribution to the epidemiology of human aspergillosis).

    PubMed

    Staib, F; Mishra, S K; Blisse, A

    1980-02-29

    The soil of potted ornamental plants as a reservoir for Aspergillus species pathogenic for man is of epidemiological and ecological interest. Isolation of A. niger as the sole hyphomycete from the soil of potted African violets (Saintpaulia ionantha, Gesneriaceae), prompted us to look for A. inger on the surface of the roots of this plant. Small pieces of the roots were inoculated in the nutrient-free agar-gel with and without antibiotics. On the antibiotic-free gel, a dense growth of Streptomyces griseus was consistently observed around the root pieces. But the gel fortified with antibiotics showed pure growth of only A. niger. One of the two strains of S. ariseus isolated from the African violet, showed inhibitory effect against a number of fungi including A. niger but the other strain had no effect on this fungus. The possible influence of streptomycetes on the occurrence of aspergilli in the soil of potted ornamental plants is discussed. PMID:6769046

  4. Flotation of cadmium-loaded biomass

    SciTech Connect

    Matis, K.A.; Zouboulis, A.I. . Chemical Technology Div.)

    1994-07-01

    Biosorption of heavy metal ions such as Cd[sup 2+] by dead biomass has been recognized as a potential alternative to existing removal technologies applied to wastewater treatment. Two bacterial strains were studied in the laboratory, Streptomyces griseus and S. clavuligerus, an industrial by-product. Both washed and unwashed samples were examined. Foam flotation is proposed in this work as the separation stage following biosorption. Effective biomass separation was conducted in the presence of a frother, ethanol. The pH of the solution was a crucial parameter for flotation and also for metal binding. Other basic parameters of flotation examined were the initial cadmium concentration in the dilute aqueous solution and the quantity of biomass used. A study of [zeta]-potential measurements of the actinomycetes was carried out under the conditions used in the separation; surface tension was also measured. These provided useful information on the process.

  5. Challenges in the Synthesis of a Unique Mono-Carboxylic Acid Antibiotic (+)-Zincophorin

    PubMed Central

    Song, Zhenlei; Lohse, Andrew G.; Hsung, Richard P.

    2009-01-01

    (+)-Zincophorin, also referred to as M144255 or griseochellin, is a polyoxygenated ionophoric antibiotic that was isolated from Streptomyces griseus in 1984. It possesses strong in vivo activity against Gram-positive bacteria and Clostridium coelchii. Its methyl ester was reported in a patent as having strong inhibitory properties against influenza WSN/virus with reduced toxicity for the host cell. Its ability to strongly bind with Zn2+, which is also present in its X-ray structure, is the basis for its name. Over the last two decades, (+)-zincophorin h as attracted an impressive array of synthetic efforts including Danishefsky's first total synthesis along with two recent elegant total syntheses reported by Cossy and Miyashita as well as our own formal total synthesis. This Account provides a comparison of the different synthetic efforts on this novel mono-carboxylic acid antibiotic and documents its interesting isolation, structure determination, and biological activities. PMID:19642422

  6. Behavioral Response of Reef Fish and Green Sea Turtles to Midfrequency Sonar.

    PubMed

    Watwood, Stephanie L; Iafrate, Joseph D; Reyier, Eric A; Redfoot, William E

    2016-01-01

    There is growing concern over the potential effects of high-intensity sonar on wild fish populations and commercial fisheries. Acoustic telemetry was employed to measure the movements of free-ranging reef fish and sea turtles in Port Canaveral, FL, in response to routine submarine sonar testing. Twenty-five sheepshead (Archosargus probatocephalus), 28 gray snapper (Lutjanus griseus), and 29 green sea turtles (Chelonia mydas) were tagged, with movements monitored for a period of up to 4 months using an array of passive acoustic receivers. Baseline residency was examined for fish and sea turtles before, during, and after the test event. No mortality of tagged fish or sea turtles was evident from the sonar test event. There was a significant increase in the daily residency index for both sheepshead and gray snapper at the testing wharf subsequent to the event. No broad-scale movement from the study site was observed during or immediately after the test. PMID:26611089

  7. Insights using a molecular approach into the life cycle of a tapeworm infecting great white sharks.

    PubMed

    Randhawa, Haseeb S

    2011-04-01

    The great white shark Carcharodon carcharias Linnaeus, 1758 is a versatile and fierce predator (and responsible for many shark attacks on humans). This apex predator feeds on a wide range of organisms including teleosts, other elasmobranchs, cephalopods, pinnipeds, and cetaceans. Although much is known about its diet, no trophic links have been empirically identified as being involved in the transmission of its tapeworm parasites. Recently, the use of molecular tools combined with phylogenetics has proven useful to identify larval and immature stages of marine tapeworms; utilization of the technique has been increasing rapidly. However, the usefulness of this approach remains limited by the availability of molecular data. Here, I employed gene sequence data from the D2 region of the large subunit of ribosomal DNA to link adults of the tapeworm Clistobothrium carcharodoni Dailey and Vogelbein, 1990 (Cestoda: Tetraphyllidea) to larvae for which sequence data for this gene are available. The sequences from the adult tapeworms were genetically identical (0% sequence divergence) to those available on GenBank for "SP" 'small' Scolex pleuronectis recovered from the striped dolphin (Stenella coeruleoalba) and Risso's dolphin (Grampus griseus). This study is the first to provide empirical evidence linking the trophic interaction between great white sharks and cetaceans as a definitive route for the successful transmission of a tetraphyllidean tapeworm. Using the intensity of infection data from this shark and from cetaceans as proxies for the extent of predation, I estimate that this individual shark would have consumed between 9 to 83 G. griseus , fresh, dead, or both, in its lifetime. PMID:21506792

  8. [Morphology of gametes in sea urchins from Peter the Great Bay, Sea of Japan].

    PubMed

    Drozdov, A L; Vinnikova, V V

    2010-01-01

    The fine structure of the gametes in six sea urchin species of the Sea of Japan was studied. The spermatozoons in Strongylocentrotus nudus, S. intermedius, Echinocardium cordatum, Scaphechinus mirabilis, Sc. grizeus and Echinarachnius parma are species-specific. The conical head and symmetrically disposed ring-shape mitochondrion are common to regular sea urchin sperm cells. S. nudus is characterized by the bulb-shaped head of the zoosperm; S. intermedius, by a bullet-shaped one. The zoosperm spearhead and small amount of postacrosome material are common to irregular sea urchins; the sperm width: length ratio varies for different species, with the highest for Sc. mirabilis. The zoosperm of Sc. griseus is characterized by two lipid drops in the cell center. Asymmetrical mitochondrion disposal is usual for E. parma. Actin filaments are found in the postacrosome material in the zoosperm of cordiform sea urchins. The differences in the fine structure of zoosperm in eurybiont species Ech. cordatum inhabiting the Sea of Japan and coastal areas of the Northeast Atlantic may bear record to the complex existence of species Ech. cordatum. The fine structure of zoosperm is unique for each of the studied families, Strongylocentrotidae, Scutellidae, and Loveniidae. The eggs of all the species are characterized by vitelline and tremelloid membranes. The vitelline membrane is formed by cytoplasm protrusions; the area between them is filled with fubrillary material. The tremelloid membrane is formed by fubrillary material associated with apical parts of microvilli of the vitelline membrane. The irregular sea urchins Sc. griseus, Sc. mirabilis and E. parma are characterized by chromatophores situated in the tremelloid membrane, with the highest abundance in Sc. mirabilis. PMID:20184121

  9. Intraguild Predation in Heteroptera: Effects of Density and Predator Identity on Dipteran Prey.

    PubMed

    Brahma, S; Sharma, D; Kundu, M; Saha, N; Saha, G K; Aditya, G

    2015-08-01

    In tropical freshwaters, different species of water bugs (Heteroptera) constitute a guild sharing similar prey resources including chironomid and mosquito larvae. Assuming possibilities of intraguild predation (IGP) among the constituent members, an attempt was made to evaluate the effects of prey and predator density on the mortality of mosquito and chironomid larvae (shared prey), using Laccotrephes griseus Guérin-Méneville (Hemiptera: Nepidae) and Ranatra filiformis Fabricius (Hemiptera: Nepidae) as IG predators and Anisops bouvieri Kirkaldy (Hemiptera: Notonectidae) as IG prey. The predation on mosquito and chironomid larvae varied with the density and combinations of the predators. When present as conspecific IG predators, L. griseus exhibited greater effect on the prey mortality than R. filiformis. The effects on shared prey suggest that the two predators are not substitutable in terms of the effect on the shared prey mortality. The mortality of A. bouvieri (IG prey) at low shared prey density was significantly different (p < 0.05) from high shared prey density. In view of predatory effect of the heteropteran predators on the dipteran larvae, the results suggest possible interference by the presence of A. bouvieri as an intermediate predator. It seems that the presence of heteropteran predators including A. bouvieri as IG prey may benefit the dipteran prey under situations when the density is low in tropical waters. The intensity of the predatory effect may differ based on the species composition at IG predator level. For mosquito biological control, the interactions between the predators may not be substitutable and are independent in their effects. PMID:26174962

  10. Distribution and Phylogenetic Analysis of Family 19 Chitinases in Actinobacteria

    PubMed Central

    Kawase, Tomokazu; Saito, Akihiro; Sato, Toshiya; Kanai, Ryo; Fujii, Takeshi; Nikaidou, Naoki; Miyashita, Kiyotaka; Watanabe, Takeshi

    2004-01-01

    In organisms other than higher plants, family 19 chitinase was first discovered in Streptomyces griseus HUT6037, and later, the general occurrence of this enzyme in Streptomyces species was demonstrated. In the present study, the distribution of family 19 chitinases in the class Actinobacteria and the phylogenetic relationship of Actinobacteria family 19 chitinases with family 19 chitinases of other organisms were investigated. Forty-nine strains were chosen to cover almost all the suborders of the class Actinobacteria, and chitinase production was examined. Of the 49 strains, 22 formed cleared zones on agar plates containing colloidal chitin and thus appeared to produce chitinases. These 22 chitinase-positive strains were subjected to Southern hybridization analysis by using a labeled DNA fragment corresponding to the catalytic domain of ChiC, and the presence of genes similar to chiC of S. griseus HUT6037 in at least 13 strains was suggested by the results. PCR amplification and sequencing of the DNA fragments corresponding to the major part of the catalytic domains of the family 19 chitinase genes confirmed the presence of family 19 chitinase genes in these 13 strains. The strains possessing family 19 chitinase genes belong to 6 of the 10 suborders in the order Actinomycetales, which account for the greatest part of the Actinobacteria. Phylogenetic analysis suggested that there is a close evolutionary relationship between family 19 chitinases found in Actinobacteria and plant class IV chitinases. The general occurrence of family 19 chitinase genes in Streptomycineae and the high sequence similarity among the genes found in Actinobacteria suggest that the family 19 chitinase gene was first acquired by an ancestor of the Streptomycineae and spread among the Actinobacteria through horizontal gene transfer. PMID:14766598

  11. Naturally Occurring Isoleucyl-tRNA Synthetase without tRNA-dependent Pre-transfer Editing*

    PubMed Central

    Cvetesic, Nevena; Dulic, Morana; Bilus, Mirna; Sostaric, Nikolina; Lenhard, Boris; Gruic-Sovulj, Ita

    2016-01-01

    Isoleucyl-tRNA synthetase (IleRS) is unusual among aminoacyl-tRNA synthetases in having a tRNA-dependent pre-transfer editing activity. Alongside the typical bacterial IleRS (such as Escherichia coli IleRS), some bacteria also have the enzymes (eukaryote-like) that cluster with eukaryotic IleRSs and exhibit low sensitivity to the antibiotic mupirocin. Our phylogenetic analysis suggests that the ileS1 and ileS2 genes of contemporary bacteria are the descendants of genes that might have arisen by an ancient duplication event before the separation of bacteria and archaea. We present the analysis of evolutionary constraints of the synthetic and editing reactions in eukaryotic/eukaryote-like IleRSs, which share a common origin but diverged through adaptation to different cell environments. The enzyme from the yeast cytosol exhibits tRNA-dependent pre-transfer editing analogous to E. coli IleRS. This argues for the presence of this proofreading in the common ancestor of both IleRS types and an ancient origin of the synthetic site-based quality control step. Yet surprisingly, the eukaryote-like enzyme from Streptomyces griseus IleRS lacks this capacity; at the same time, its synthetic site displays the 103-fold drop in sensitivity to antibiotic mupirocin relative to the yeast enzyme. The discovery that pre-transfer editing is optional in IleRSs lends support to the notion that the conserved post-transfer editing domain is the main checkpoint in these enzymes. We substantiated this by showing that under error-prone conditions S. griseus IleRS is able to rescue the growth of an E. coli lacking functional IleRS, providing the first evidence that tRNA-dependent pre-transfer editing in IleRS is not essential for cell viability. PMID:26921320

  12. Phosphorylation of the AfsR product, a global regulatory protein for secondary-metabolite formation in Streptomyces coelicolor A3(2).

    PubMed Central

    Hong, S K; Kito, M; Beppu, T; Horinouchi, S

    1991-01-01

    The AfsR protein is essential for the biosynthesis at the wild-type level of A-factor, actinorhodin, and undecylprodigiosin in Streptomyces coelicolor A3(2) and Streptomyces lividans. Because overexpression of the afsR gene caused some deleterious effect on these strains, a multicopy plasmid carrying the whole afsR gene was introduced into Streptomyces griseus, from which a crude cell lysate was prepared as a protein source. The AfsR protein was purified to homogeneity from the cytoplasmic fraction through several steps of chromatography, including affinity column chromatography with ATP-agarose and use of anti-AfsR antibody for its detection. The molecular weight of AfsR was estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by gel filtration to be 105,300, which is in good agreement with that deduced from the nucleotide sequence of afsR. The purified AfsR protein was found to be phosphorylated through the transfer of the gamma-phosphate group of ATP in the presence of the cell extracts of S. coelicolor A3(2) and S. lividans. This phosphorylation proceeded very rapidly, and no competition was observed with CTP, GTP, UTP, or cyclic AMP. In the cell extract of S. griseus, no activity phosphorylating the AfsR protein was detected, suggesting that this activity is not generally present in Streptomyces spp. but is specific to certain species. It is conceivable that the extent of phosphorylation of the AfsR protein modulates its regulatory activity which, in turn, regulates expression of some target gene(s) involved in the secondary-metabolite formation in S. coelicolor A3(2). Images PMID:2007554

  13. Identification and functional analysis of genes controlling biosynthesis of 2-methylisoborneol

    PubMed Central

    Komatsu, Mamoru; Tsuda, Muneya; Ōmura, Satoshi; Oikawa, Hideaki; Ikeda, Haruo

    2008-01-01

    To identify the genes for biosynthesis of the off-flavor terpenoid alcohol, 2-methylisoborneol (2-MIB), the key genes encoding monoterpene cyclase were located in bacterial genome databases by using a combination of hidden Markov models, protein–family search, and the sequence alignment of their gene products. Predicted terpene cyclases were classified into three groups: sesquiterpene, diterpene, and other terpene cyclases. Genes of the terpene cyclase group that form an operon with a gene encoding S-adenosyl-l-methionine (SAM)-dependent methyltransferase were found in genome data of seven microorganisms belonging to actinomycetes, Streptomyces ambofaciens ISP5053, Streptomyces coelicolor A3(2), Streptomyces griseus IFO13350, Streptomyces lasaliensis NRRL3382R, Streptomyces scabies 87.22, Saccharopolyspora erythraea NRRL2338, and Micromonospora olivasterospora KY11048. Among six microorganisms tested, S. ambofaciens, S. coelicolor A3(2), S. griseus, and S. lasaliensis produced 2-MIB but M. olivasterospora produced 2-methylenebornane (2-MB) instead. The regions containing monoterpene cyclase and methyltransferase genes were amplified by PCR from S. ambofaciens, S. lasaliensis, and Saccharopolyspora erythraea, respectively, and their genes were heterologously expressed in Streptomyces avermitilis, which was naturally deficient of 2-MIB biosynthesis by insertion and deletion. All exoconjugants of S. avermitilis produced 2-MIB. Full-length recombinant proteins, monoterpene cyclase and methyltransferase of S. lasaliensis were expressed at high level in Escherichia coli. The recombinant methyltransferase catalyzed methylation at the C2 position of geranyl diphosphate (GPP) in the presence of SAM. 2-MIB was generated by incubation with GPP, SAM, recombinant methyltransferase, and terpene cyclase. We concluded that the biosynthetic pathway involves the methylation of GPP by GPP methyltransferase and its subsequent cyclization by monoterpene cyclase to 2-MIB. PMID

  14. Phylogenetic relationships among Lemuridae (Primates): evidence from mtDNA.

    PubMed

    Pastorini, Jennifer; Forstner, Michael R J; Martin, Robert D

    2002-10-01

    The family Lemuridae includes four genera: Eulemur, Hapalemur, Lemur,Varecia. Taxonomy and phylogenetic relationships between L. catta, Eulemur and Hapalemur, and of Varecia to these other lemurids, continue to be hotly debated. Nodal relationships among the five Eulemur species also remain contentious. A mitochondrial DNA sequence dataset from the ND 3, ND 4 L, ND 4 genes and five tRNAs (Gly, Arg, His, Ser, Leu) was generated to try to clarify phylogenetic relationships w ithin the Lemuridae. Samples (n=39) from all ten lemurid species were collected and analysed. Three Daubentonia madagascariensis were included as outgroup taxa. The approximately 2400 bp sequences were analysed using maximum parsimony, neighbor-joining and maximum likelihood methods. The results support monophyly of Eulemur, a basal divergence of Varecia, and a sister-group relationship for Lemur/Hapalemur. Based on tree topology, bootstrap values, and pairwise distance comparisons, we conclude thatVarecia and Eulemur both represent distinct genera separate from L. catta. H. griseus andH. aureus form a clade with strong support, but the sequence data do not permit robust resolution of the trichotomy involving H. simus, H. aureus/H. griseus and L. catta. Within Eulemur there is strong support for a clade containing E. fulvus, E. mongoz and E. rubriventer. However, analyses failed to clearly resolve relationships among those three species or with the more distantly related E. coronatus and E. macaco. Our sequencing data support the current subspecific status of E.m. macaco and E.m. flavifrons, and that of V.v. variegata and V.v. rubra. However, tree topology and relatively large genetic distances among individual V.v. variegata indicate that there may be more phylogenetic structure within this taxon than is indicated by current taxonomy. PMID:12393004

  15. Grados de comprobación de estudios de terapias integrales (PDQ®)—Versión para profesionales de salud

    Cancer.gov

    Información acerca de cómo sopesar la fuerza de los datos probatorios obtenidos de los estudios de investigación sobre terapias integrales, alternativas y complementarias en seres humanos con cáncer.

  16. Stem biomechanics of three columnar cacti from the Sonoran Desert.

    PubMed

    Molina-Freaner, F; Tinoco-Ojanguren, C; Niklas, K

    1998-08-01

    The allometric relationship of stem length L with respect to mean stem diameter D was determined for 80 shoots of each of three columnar cactus species (Stenocereus thurberi, Lophocereus schottii, and S. gummosus) to determine whether this relationship accords with that predicted by each of three contending models purporting to describe the mechanical architecture of vertical shoots (i.e., geometric, stress, and elastic similitude, which predict L proportional to D(alpha), with alpha = 1/1, 1/2, and 2/3, respectively). In addition, anatomical, physical, and biomechanical stem properties were measured to determine how the stems of these three species maintain their elastic stability as they increase in size. Reduced major axis regression of L with respect to D showed that alpha = 2.82 ± 0.14 for S. thurberi, 2.32 ± 0.19 for L. schottii, and 4.21 ± 0.31 for S. gummosus. Thus, the scaling exponents for the allometry of L differed significantly from that predicted by each of the three biomechanical models. In contrast, these exponents were similar to that for the allometry previously reported for saguaro. Analyses of biomechanical data derived from bending tests performed on 30 stems selected from each of the three species indicated that the bulk stem tissue stiffness was roughly proportional to L2, while stem flexural rigidity (i.e., the ability to resist a bending force) scaled roughly as L3. Stem length was significantly and positively correlated with the volume fraction of wood, while regression analysis of the pooled data from the three species (i.e., 90 stems) indicated that bulk tissue stiffness scaled roughly as the 5/3-power of the volume fraction of wood in stems. These data were interpreted to indicate that wood served as the major stiffening agent in stems and that this tissue accumulates at a sufficient rate to afford unusually high scaling exponents tot stem length with respect to stem diameter (i.e., disproportionately large increments of stem length

  17. In situ Management and Domestication of Plants in Mesoamerica

    PubMed Central

    Casas, Alejandro; Otero-Arnaiz, Adriana; Pérez-Negrón, Edgar; Valiente-Banuet, Alfonso

    2007-01-01

    Background and Aims Ethnobotanical studies in Mexico have documented that Mesoamerican peoples practise systems of in situ management of wild and weedy vegetation directed to control availability of useful plants. In situ management includes let standing, encouraging growing and protection of individual plants of useful species during clearance of vegetation, which in some cases may involve artificial selection. The aim of this study was to review, complement and re-analyse information from three case studies which examined patterns of morphological, physiological and genetic effects of artificial selection in plant populations under in situ management in the region. Methods Information on wild and in situ managed populations of the herbaceous weedy plants Anoda cristata and Crotalaria pumila, the tree Leucaena esculenta subsp. esculenta and the columnar cacti Escontria chiotilla, Polaskia chichipe and Stenocereus stellatus from Central Mexico was re-analysed. Analyses compared morphology and frequency of morphological variants, germination patterns, and population genetics parameters between wild and managed in situ populations of the species studied. Species of columnar cacti are under different management intensities and their populations, including cultivated stands of P. chichipe and S. stellatus, were also compared between species. Key Results Significant differences in morphology, germination patterns and genetic variation documented between wild, in situ managed and cultivated populations of the species studied are associated with higher frequencies of phenotypes favoured by humans in managed populations. Genetic diversity in managed populations of E. chiotilla and P. chichipe is slightly lower than in wild populations but in managed populations of S. stellatus variation was higher than in the wild. However, genetic distance between populations was generally small and influenced more by geographic distance than by management. Conclusions Artificial

  18. [Oleksandr Solomonovych Tsyperovych--gifted enzymologist, scientist and practician].

    PubMed

    Vynohradova, R P; Kolodzeĭs'ka, M V

    2007-01-01

    Professor O. S. Tsyperovich (15.12.1910-20.12.1976), Doctor of biology, was born in the city of Odessa, graduated from the Faculty of Chemistry of Shevchenko Kyiv State University as a specialist in organic chemistry (1930-1935). In 1935-1941 he worked at the Institute of Biochemistry of the Academy of Sciences of the Ukr.SSR (Kyiv) as a junior research worker, and then as a senior research worker at the Department of Enzymology. In 1941 O. S. Tsyperovich defended the thesis for the Candidate's degree dedicated to the investigation of synthetic effect of proteolytic enzymes, and he was awarded the title of the senior research worker. In 1941-1945 O. S. Tsyperovich struggled in the ranks of the Soviet Army, was awarded the Red Star Order, medals For Defense of Caucasus, For the Victory over Germany in the Great Patriotic War of 1941-1945. In 1946-1976 O. S. Tsyperovich worked at the Institute of Biochemistry of the Academy of Sciences of Ukraine. When investigating the mechanism of proteins denaturation he discovered the phenomenon of their "denaturational stabilization". New technological schemes of production of pepsin preparations were elaborated on the basis of the method of autholysis proposed by him. In 1954 O. S. Tsyperovich defended the thesis for the Doctor's Degree and was awarded the order The Badge of Honor. Beginning from 1963 he headed the laboratory, and from 1966 -- the Department of Chemistry and Biochemistry of Enzymes, in 1969 the title of professor was conferred on him. In the 60-70's O. S. Tsyperovich investigated hydrolytic enzymes of microorganisms with the purpose of their use in industry. Thus, the method of production of the preparation "pronasa" from Streptomyces griseus was developed, aminopeptidases, dipeptidases, a-amylase, cellulases, were investigated. Investigations in the field of preparative enzymology resulted in the development of technological scheme for creation of the following drugs for the purposes of medicine: medical

  19. Hospital Universiti Sains Malaysia (HUSM): 25 Years Of Excellent Service.

    PubMed

    Kamari, Zaidun

    2009-01-01

    Our Hospital University Sains Malaysia (HUSM) was given the Cabinet approval to exist under the Ministry of Education on 23 November 1982. The Deputy Prime Minister during that period, Yang Berhormat Tun Musa Hitam announced this after the cabinet meeting was held together with the presence of the Yang Berhormat Ministers of Health; and Education, Director of the Public Works Department and the Implementation and Coordinating Unit, Prime Minister's Department. The first patients moved in on 14 March 1983 and the inauguration of HUSM was done on 26 August 1984 by the Duli Yang Maha Mulia Tuanku Ismail Petra Ibni Al-Marhum Sultan Yahya Petra, the Sultan of Kelantan Darul Naim. HUSM celebrated it's 25th anniversary at the Dewan Utama, USM Health Campus on the 15th December 2008 which was inaugurated by Yang Berhormat, Minister of Higher Education Dato' Seri Mohamed Khaled Nordin. USM's Vice Chancellor Professor Tan Sri Dato' Dzulkifli Abdul Razak, Chairman of the USM Board of Directors Tan Sri Dato' Haji Dr. Ani bin Arope, Health Campus Director Professor Dato' Dr. Mafauzy Mohamed, former Campus Director, Dato' Prof Mohd Roslani Abdul Majid, the current and previous Hospital Directors and Deputy Directors since 1983 were present. The achievements of HUSM since its establishment and its vision to fulfil the University's Accelerated Programme for Excellence (APEX) are elaborated. PMID:22589644

  20. Fluorescent microbead-based immunoassay for anti-Erysipelothrix rhusiopathiae antibody detection in cetaceans.

    PubMed

    Melero, Mar; Giménez-Lirola, Luis G; Rubio-Guerri, Consuelo; Crespo-Picazo, José Luis; Sierra, Eva; García-Párraga, Daniel; García-Peña, Francisco Javier; Arbelo, Manuel; Álvaro, Teresa; Valls, Mónica; Sánchez-Vizcaíno, José Manuel

    2016-01-13

    A fluorescent microbead-based immunoassay (FMIA) for detection of anti-Erysipelothrix rhusiopathiae antibodies in pigs was adapted for use in cetaceans. The FMIA was validated and adjusted using serum samples from 10 vaccinated captive bottlenose dolphins Tursiops truncatus collected between 1 and 13 mo after immunization. The technique was then used to analyze specimens from 15 free-ranging cetaceans stranded alive on the Valencian Mediterranean coast between 2006 and 2014: 11 striped dolphins Stenella coeruleoalba, 3 Risso's dolphins Grampus griseus and 1 bottlenose dolphin Tursiops truncatus. One of these wild animals was confirmed to have died from E. rhusiopathiae septicemia, but no anti-E. rhusiopathiae antibodies were detected in its serum, pericardial fluid or milk samples. Another free-ranging individual, which lacked any signs or lesions that might be indicative of E. rhusiopathiae infection, showed high fluorescence intensity similar to that measured in captive dolphins at 6-13 mo after vaccination. These results suggest that this animal underwent an E. rhusiopathiae infection several months before stranding. The findings in the present study suggest that FMIA can be useful for detecting anti-E. rhusiopathiae antibodies in cetaceans, and its application to free-ranging animals is particularly interesting because of the great value of these specimens. Furthermore, the FMIA can be multiplexed to allow the determination of up to 100 analytes per sample in a single well, thereby reducing the cost, time and sample volume needed. PMID:26758657

  1. Prey preferences among the community of deep-diving odontocetes from the Bay of Biscay, Northeast Atlantic

    NASA Astrophysics Data System (ADS)

    Spitz, Jérôme; Cherel, Yves; Bertin, Stéphane; Kiszka, Jeremy; Dewez, Alexandre; Ridoux, Vincent

    2011-03-01

    Long-finned pilot whales ( Globicephala melas), Risso's dolphins ( Grampus griseus), melon-headed whales ( Peponocephala electra), Cuvier's beaked whales ( Ziphius cavirostris), Sowerby's beaked whales ( Mesoplodon bidens), northern bottlenose whales ( Hyperoodon ampullatus), sperm whales ( Physeter macrocephalus), dwarf sperm whales ( Kogia sima) and pygmy sperm whales ( Kogia breviceps) make up the large community of deep-diving odontocetes occurring off the Bay of Biscay, northeast Atlantic. The ecology of these toothed cetaceans is poorly documented worldwide. The present study described their prey preferences from stomach content analysis and showed resource partitioning within the assemblage. The majority of the species appeared to be mostly teutophageous. Fish was an important food source only for the Sowerby's beaked whale and, to a lesser extent, for the long-finned pilot whale. In terms of foraging habitats inferred from prey composition, either pelagic oceanic or demersal neritic habitats were exploited by toothed whales in the Bay of Biscay, with only the long-finned pilot whale foraging in the two habitats. Finally, with more than 14,000 identified cephalopods from 39 species, the present study highlighted also the poorly known deep-sea cephalopod community off the Bay of Biscay using top predators as biological samplers.

  2. Resynthesis of reactive site peptide bond and temporary inhibition of Streptomyces metalloproteinase inhibitor.

    PubMed

    Seeram, S S; Hiraga, K; Oda, K

    1997-10-01

    Streptomyces metalloproteinase inhibitor (SMPI) is a small proteinaceous inhibitor which inhibits metalloproteinases such as thermolysin (Ki =1.14 x 10(-10) M). When incubated with the enzyme, it is gradually hydrolyzed at the Cys64-Val65 peptide bond, which was identified as the reactive site by mutational analysis. To achieve a further understanding of the inhibition mechanism, we attempted to resynthesize the cleaved reactive site by using the enzyme catalytic action. The native inhibitor was resynthesized from the modified inhibitor (Ki =2.18 x 10(-8) M) by incubation with a catalytic amount of thermolysin under the same conditions as used for hydrolysis (pH 7.5, 25 degrees C), suggesting that SMPI follows the standard mechanism of inhibition of serine proteinase inhibitors. Temporary inhibition was observed when the native inhibitor and thermolysin were incubated at a 1:100 (mol/mol) enzyme-inhibitor ratio at 37 degrees C. SMPI showed temporary inhibition towards all the enzymes it inhibited. The inhibitory spectrum of SMPI was analyzed with various metalloproteinases based on the Ki values and limited proteolysis patterns. Pseudomonas elastase and Streptomyces griseus metalloproteinase II formed more stable complexes and showed much lower Ki values (approximately 2 pM) than thermolysin. In the limited proteolysis experiments weak inhibitors were degraded by the enzymes. SMPI did not inhibit almelysin, Streptomyces caespitosus neutral proteinase or matrix metalloproteinases. SMPI specifically inhibits metalloproteinases which are sensitive to phosphoramidon. PMID:9399583

  3. Sequence analysis of the aminoacylase-1 family. A new proposed signature for metalloexopeptidases.

    PubMed

    Biagini, A; Puigserver, A

    2001-03-01

    The amino acid sequence analysis of the human and porcine aminoacylases-1, the carboxypeptidase S precursor from Saccharomyces cerevisiae, the succinyl-diaminopimelate desuccinylase from Escherichia coli, Haemophilus influenzae and Corynebacterium glutamicum, the acetylornithine deacetylase from Escherichia coli and Dictyostelium discoideum and the carboxypeptidase G(2) precursor from Pseudomonas strain, using the Basic Local Alignment Search Tool (BLAST) and the Position-Specific Iterated BLAST (PSI-BLAST), allowed us to suggest that all these enzymes, which share common functional and biochemical features, belong to the same structural family. The three amino acid blocks which were found to be highly conserved, using the CLUSTAL W program, could be assigned to the catalytic active site, based on the general three-dimensional structure of the carboxypeptidase G(2) from the Pseudomonas strain precursor. Six additional proteins with the same signature have been retrieved after performing two successive PSI-BLAST iterations using the sequence of the conserved motif, namely Lactobacillus delbrueckii aminoacyl-histidine dipeptidase, Streptomyces griseus aminopeptidase, Saccharomyces cerevisiae aminopeptidase Y precursor, two Bacillus stearothermophilus N-carbamyl-L-amino acid amidohydrolases and Pseudomonas sp. hydantoin utilization protein C. The three conserved amino acid motifs corresponded to the following blocks: (i) [S, G, A]-H-x-D-x-V; (ii) G-x-x-D; and (iii) x-E-E. This new sequence signature is clearly different from that commonly reported in the literature for proteins belonging to the ArgE/DapE/CPG2/YscS family. PMID:11250542

  4. Recombinant expression, biochemical characterization and stabilization through proteolysis of an L-glutamate oxidase from Streptomyces sp. X-119-6.

    PubMed

    Arima, Jiro; Tamura, Takashi; Kusakabe, Hitoshi; Ashiuchi, Makoto; Yagi, Toshiharu; Tanaka, Hidehiko; Inagaki, Kenji

    2003-12-01

    L-glutamate oxidase (LGOX) from Streptomyces sp. X-119-6 is a protein of 150 kDa that has hexamer structure alpha2beta2gamma2. The gene encoding LGOX was cloned and heterologously expressed in Escherichia coli. LGOX isolated from the E. coli transformant had the structure of a one chain polypeptide. Although the recombinant LGOX exhibited catalytic activity, it was inferior to the LGOX isolated from Streptomyces sp. X-119-6 in catalytic efficiency. The recombinant LGOX exhibited low thermostability compared to the LGOX isolated from Streptomyces sp. X-119-6 and was an aggregated form. Proteolysis of the recombinant LGOX with the metalloendopeptidase from Streptomyces griseus (Sgmp) improved its catalytic efficiency at various pH. Furthermore, the Sgmp-treated recombinant LGOX had a subunit structure of alpha2beta2gamma2 and nearly the same enzymological character as the LGOX isolated from Streptomyces sp. X-119-6. A higher molecular species observed for the recombinant LGOX was not detected for the Sgmp-treated recombinant LGOX. These results prove that proteolysis by Sgmp is involved in the stabilization of the recombinant LGOX. PMID:14769868

  5. Non-specific depolymerization of chitosan by pronase and characterization of the resultant products.

    PubMed

    Kumar, Acharya B Vishu; Gowda, Lalitha R; Tharanathan, Rudrapatnam N

    2004-02-01

    Pronase (type XXV serine protease from Streptomyces griseus) efficiently depolymerizes chitosan, a linear beta-->1,4-linked polysaccharide of 2-amino-deoxyglucose and 2-amino-2-N-acetylamino-D-glucose, to low-molecular weight chitosans (LMWC), chito-oligomers (degree of polymerization, 2-6) and monomer. The maximum depolymerization occurred at pH 3.5 and 37 degrees C, and the reaction obeyed Michaelis-Menten kinetics with a Km of 5.21 mg.mL(-1) and Vmax of 138.55 nmoles.min(-1).mg(-1). The molecular mass of the major product, LMWC, varied between 9.0 +/- 0.5 kDa depending on the reaction time. Scanning electron microscopy of LMWC showed an approximately eightfold decrease in particle size and characterization by infrared spectroscopy, circular dichroism, X-ray diffractometry and 13C-NMR revealed them to possess a lower degree of acetylation, hydration and crystallinity compared to chitosan. Chitosanolysis by pronase is an alternative and inexpensive method to produce a variety of chitosan degradation products that have wide and varied biofunctionalities. PMID:14764087

  6. The role of Cu(I)-thiolate clusters during the proteolysis of Cu-thionein.

    PubMed

    Weser, U; Mutter, W; Hartmann, H J

    1986-03-01

    Rat liver Cu,Zn-[35S]thionein and yeast Cu-thionein were subjected to proteolysis in vitro using equilibrium dialysis. The partially copper-loaded vertebrate thionein (2-7 Cu/mol) was affected by different proteases including thermolysin, proteinase K, protease from Streptomyces griseus and lysosomal enzymes. Unlike the 2Cu-thionein the respective 7Cu-thiolate-centred metallothionein was hardly proteolytically digested. In contrast to fully copper-loaded native yeast Cu-thionein both the H2O2-oxidized and the metal-free protein were effectively cleaved in the presence of proteinase K. It is important to realize that the native Cu(I)-thiolate chromophore survives the proteolytic attack. When the copper-sulphur bonding is broken and the same amount of copper is unspecifically bound to the thionein portion, proteolysis proceeds identically with respect to the rate observed in the presence of the apoprotein. The unsuccessful proteolysis of native Cu-thionein is not attributable to a simple copper-dependent inhibition of the proteinases. It is suggested that prior to proteolysis the copper-sulphur clusters must be destroyed. PMID:3081372

  7. Anoikis-resistant MDCK cells carrying susceptibilities to TNF-alpha and verotoxin that are suitable for influenza virus cultivation.

    PubMed

    Tsutsumi, Reiko; Fujisaki, Shigemi; Shozushima, Masanori; Saito, Koichi; Sato, Shigehiro

    2006-10-01

    Madin-Darby canine kidney (MDCK) cells were originally anchorage-dependent epithelial cells. Here, we have isolated a novel MDCK-derived cell population, termed 6 M-4, by means of culturing MDCK cells in suspension for nearly 6 months in the presence of Streptomyces griseus metalloendopeptidase (MEP). The isolated cells showed unique proliferation characteristics, which differed from parental MDCK cells. They proliferated adherently on a polystyrene matrix, but proliferated non-adherently both in the presence of MEP and on a non-adhesive matrix coated with poly 2-methacryloyloxyethyl phosphorylcholine (MPC). The 6 M-4 cells consisted of at least two cell types. One type, termed 6 M-4-TR7, would not grow in soft agar and showed a novel phenotype in that the cells were susceptible to both TNF-alpha and verotoxin 1 (VT1). In addition, the isolated adhesion-independent cells sustained epithelial traits of parental MDCK cells. We further show that these MDCK-derivative cells are suitable for influenza virus cultivation. Hemagglutination (HA) titers of influenzaviruses A and B were increased in the suspension culture of 6 M-4-TR7 cells supplemented with the MEP in comparison to adherently growing cells in the presence of trypsin. PMID:19002866

  8. Disulfide bridge structure of ascidian trypsin inhibitor I: similarity to Kazal-type inhibitors.

    PubMed

    Kumazaki, T; Ishii, S

    1990-03-01

    The primary structures of ascidian trypsin inhibitors (iso-inhibitors I and II) were reported in the preceding paper (Kumazaki, T. et al. (1990) J. Biochem. 107, 409-413). Both of them have eight half-cystines in a molecule composed of 55 amino acid residues with a sequence showing no extensive homology to other known protease inhibitors. To locate the four disulfide bridges in the molecule, native inhibitor I was digested with thermolysin to yield cystine-containing peptides. The peptides were separated from each other by reversed-phase HPLC. A core peptide still containing six closely located half-cystines (e.g. -Cys-Arg-Cys and -Cys-Cys-) was further digested with Streptomyces griseus trypsin for cleavage of the Arg-Cys bond. On the other hand, the Cys-Cys bond was split by applying manual Edman degradation to the core peptide. Amino acid composition analyses of the resulting cystine peptides allowed us to define the whole disulfide bridge structure in the parent molecule. The topological relation between the disulfide loops and the reactive site suggested that the ascidian trypsin inhibitor may be classified as a member of the Kazal-type inhibitor family. PMID:2111316

  9. Application of bimane-peptide substrates to spectrofluorometric assays of metalloendopeptidases.

    PubMed

    Kajiwara, K; Kumazaki, T; Sato, E; Kanaoka, Y; Ishii, S

    1991-09-01

    A spectrofluorometric method for sensitive determination of metalloendopeptidase activity has been developed by using a bimane-peptide containing a tryptophan residue, i.e. 1,7-dioxo-2,5,6-trimethyl-1H,7H-pyrazolo[1,2-alpha]pyrazol-3-yl-methyl- thiomethylcarbonyl-phenylalanyl-tryptophanyl-leucine (Bim-SCH2CO-Phe-Trp-Leu-OH). Such an "intramolecularly quenched" substrate was originally designed for a sensitive assay of angiotensin I converting enzyme (ACE) [Sato, E. et al. (1989) Chem. Pharm. Bull. 37, 145-147]. All the typical metalloendopeptidases tested, such as thermolysin, Pseudomonas aeruginosa (Ps.) elastase, Streptomyces griseus metalloendopeptidases I and II (SGMPI and SGMPII), and alkinonase A, a metalloendopeptidase from Streptomyces violaceorectus, cleaved this substrate strictly at a Phe-Trp bond, leading to a marked increase in fluorescence. Kinetic parameters of the enzymatic hydrolyses of five kinds of analogous bimane substrates were compared to examine how the nature of neighboring amino acid residues on either side of the cleavable bond affects the catalytic efficiency of each of the metalloendopeptidases. Bim-SCH2CO-Phe-Trp-Leu-OH was most efficiently hydrolyzed by all of these enzymes. The use of this substrate made it possible to determine minute amounts of metalloendopeptidases, especially those originating from Streptomycetes (for example, as little as 10 fmol of SGMPII). PMID:1769960

  10. Identification of highly brominated analogues of Q1 in marine mammals.

    PubMed

    Teuten, Emma L; Pedler, Byron E; Hangsterfer, Alexandra N; Reddy, Christopher M

    2006-11-01

    Three novel halogenated organic compounds (HOCs) have been identified in the blubber of marine mammals from coastal New England with the molecular formulae C(9)H(3)N(2)Br(6)Cl, C(9)H(3)N(2)Br(7), and C(9)H(4)N(2)Br(5)Cl. They were identified using high and low resolution gas chromatography mass spectrometry (GCMS) and appear to be highly brominated analogues of Q1, a heptachlorinated HOC suspected to be naturally produced. These compounds were found in Atlantic white sided dolphin (Lagenorhynchus acutus), bottlenose dolphin (Tursiops truncatus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena), beluga whale (Delphinapterus leucas), fin whale (Balaenoptera physalus), grey seal (Halichoerus grypus), harp seal (Phoca groenlandica) and a potential food source (Loligo pealei) with concentrations as high as 2.7 microg/g (lipid weight). The regiospecificity of C(9)H(3)N(2)Br(6)Cl is suggestive of a biogenic origin. Debromination of C(9)H(3)N(2)Br(6)Cl may be significant in the formation of C(9)H(4)N(2)Br(5)Cl. PMID:16517037

  11. Static inflation and deflation pressure-volume curves from excised lungs of marine mammals.

    PubMed

    Fahlman, Andreas; Loring, Stephen H; Ferrigno, Massimo; Moore, Colby; Early, Greg; Niemeyer, Misty; Lentell, Betty; Wenzel, Frederic; Joy, Ruth; Moore, Michael J

    2011-11-15

    Excised lungs from eight marine mammal species [harp seal (Pagophilus groenlandicus), harbor seal (Phoca vitulina), gray seal (Halichoerus grypush), Atlantic white-sided dolphin (Lagenorhynchus acutus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), long-finned pilot whale (Globicephala melas) and harbor porpoise (Phocoena phocoena)] were used to determine the minimum air volume of the relaxed lung (MAV, N=15), the elastic properties (pressure-volume curves, N=24) of the respiratory system and the total lung capacity (TLC). Our data indicate that mass-specific TLC (sTLC, l kg(-1)) does not differ between species or groups (odontocete vs phocid) and agree with that estimated (TLC(est)) from body mass (M(b)) by applying the equation: TLC(est)=0.135 M(b)(0.92). Measured MAV was on average 7% of TLC, with a range from 0 to 16%. The pressure-volume curves were similar among species on inflation but diverged during deflation in phocids in comparison with odontocetes. These differences provide a structural basis for observed species differences in the depth at which lungs collapse and gas exchange ceases. PMID:22031747

  12. Impact of forest type and management strategy on avian densities in the Mississippi Alluvial Valley, USA

    USGS Publications Warehouse

    Twedt, D.J.; Wilson, R.R.; Henne-Kerr, J.L.; Hamilton, R.B.

    1999-01-01

    Avian territory densities were determined from 20 Breeding Bird Censuses in mature (>30 years) bottomland hardwood stand: and 18 Breeding Bird Censuses in young (6-9 years old) cottonwood (Populas deltoides) plantations in the Mississippi Alluvial Valley. Avian species richness, diversity, and territory density were greater (p 0.05). Even so, detrended correspondence analysis based on avian territory densities readily segregated forest types and silvicultural treatments. Timber harvest within bottomland hardwood stands resulted in a shift in bird communities toward those found in cottonwood stands by increasing the densities of early-successional species such as Indigo Bunting (Passerina cyanea), Yellow-breasted Chat (Icteria virens), and Common Yellowthroat (Geothlypis trichas). Conversely, regenerating cottonwood stands from root sprouts, rather than planting stem cuttings, resulted in a shift in bird communities toward those found in bottomland hardwood stands by increasing densities of species such as White-eyed Vireo (Vireo griseus) and Wood Thrush (Hylocichla mustelina). Tree species diversity, angular canopy cover, and midstory density were positively associated with bird species assemblages in bottomland hardwood stands, whereas vegetation density at ground level was positively associated with bird communities in cottonwood plantations. Conversion of agricultural fields to short-rotation cottonwood plantations results in increased breeding bird populations by adding up to 140 additional territories 40 ha-1. Even so, relative conservation values, derive, from indicator species analysis and Partners in Flight concern scores, suggest that mature bottomland hardwood forests are twice as 'valuable' for bird conservation as are cottonwood plantations.

  13. Biosystematics of alkaliphilic streptomycetes isolated from seven locations across a beach and dune sand system.

    PubMed

    Antony-Babu, Sanjay; Goodfellow, Michael

    2008-11-01

    Alkaliphilic streptomycetes were isolated from composite sand samples collected from six out of seven locations across a beach and dune sand system using starch-casein-nitrate agar supplemented with cycloheximide and buffered to pH 10.5. The isolates had colonial and chemotaxonomic properties consistent with their classification in the genus Streptomyces. They were assigned to 49 multimembered and 114 single-membered colour-groups given their ability to produce pigments on oatmeal and peptone-yeast-extract-iron agars and to corresponding taxa based on whole-genome rep-PCR banding patterns. Twenty-four isolates representing the colour and rep-PCR groups grew well from pH 5 to 11, and optimally at pH 9, as did phylogenetically close members of the Streptomyces griseus 16S rRNA gene clade. One hundred and twelve representative alkaliphilic streptomycetes formed a heterogeneous but distinct clade in the Streptomyces 16S rRNA gene tree. A 3-dimensional representation of 16S rRNA sequence data showed that the alkaliphilic streptomycetes formed a distinct group in multidimensional taxospace. It is evident that alkaliphilic streptomycetes are common in the beach and dune sand system and that representatives of this community form new centers of taxonomic variation within the genus Streptomyces that can be equated with species. PMID:18777141

  14. Variation in acoustic behavior of delphinids in the Pacific Ocean based on school size and species composition

    NASA Astrophysics Data System (ADS)

    Rankin, Shannon; Barlow, Jay

    2005-04-01

    Variation in acoustic behavior based on school size and species composition was examined for surveys in the eastern tropical Pacific (2000), along the U.S. West Coast (2001), and in the U.S. EEZ surrounding Hawaii (2002). Sounds were monitored using a towed hydrophone array, and vocal schools were defined as those producing any combination of whistles, burst pulses, and/or echolocation clicks. Delphinid schools containing mixed species were consistently more vocal than single species schools. Vocal schools of Stenella attenuata, S. longirostris, Delphinus delphis, and Lissodelphis borealis were significantly larger than non-vocal schools. Vocal schools of Tursiops truncatus and Grampus griseus were somewhat larger than non-vocal schools, although this relationship was not significant. There was no relationship between group size and vocal activity for S. coeruleoalba, Steno bredanensis, and Globicephala spp. For species without a strong group size effect, all but T. truncatus were more vocal in the Hawaiian waters. The ability to use acoustic techniques in dolphin population estimation depends on their effectiveness in consistently detecting dolphin schools. This study suggests that small single-species schools of S. attenuata, S. longirostris, D. delphis, and L. borealis are more likely to be missed during acoustic monitoring in these regions.

  15. Historical and current records of aquarium cetaceans in China.

    PubMed

    Zhang, Peijun; Sun, Ni; Yao, Zhiping; Zhang, Xianfeng

    2012-01-01

    The number of cetaceans housed in aquariums in China is increasing. Detailed information on the historical and current population status has not been reported, despite its importance for successful breeding and population management. Questionnaires were conducted between December 2006 and May 2009, and the information was used to construct studbooks. Our survey showed that 10 species had been introduced to aquariums since 1978, including 26 (with 15 in the current population) finless porpoises (Neophocaena phocaenoides), 5 (5) false killer whales (Pseudorca crassidens), 94 (80) common bottlenose dolphins (Tursiops truncatus), 48 (30) Indo-Pacific bottlenose dolphins (Tursiops aduncus), 36 (32) beluga whales (Delphinapterus leucas), 10 (10) pantropical spotted dolphins (Stenella attenuata), 8 (8) Risso's dolphins (Grampus griseus), 2 (2) short-finned pilot whales (Globicephala macrorhynchus), 2 (2) Pacific white-sided dolphins (Lagenorhynchus obliquidens), and 5 (0) baiji dolphins (Lipotes vexillifer). The number of cetaceans has increased markedly in the past 32 years, especially since 1995. Currently, 184 individuals are under human care throughout China, a number larger than any other country with an International Species Information System membership. In addition, the Annual Survival Rates of bottlenose dolphins (0.959) and beluga whales (0.968) were found higher than those reported previously (0.93-0.951 and 0.94-0.954, respectively). PMID:21674602

  16. Population identification of western hemisphere shorebirds throughout the annual cycle

    USGS Publications Warehouse

    Haig, Susan M.; Gratto-Trevor, C. L.; Mullins, Thomas D.; Colwell, M.A.

    1997-01-01

    Identification of relationships among geographically distinct populations of migratory species can provide an understanding of breeding and natal philopatry, migration pathways, and population mixing during winter. We used random amplified polymorphic DNA (RAPD) analyses to search for markers specific to difficult-to-differentiate shorebird species (e.g. long-billed dowitcher Limnodromus scolopaceus and short-billed dowitcher L. griseus) as well as geographically distinct breeding populations of Hudsonian godwits Limosa haemastica, red-necked phalaropes Phalaropus lobatus, semipalmated plovers Charadrius semipalmatus, dunlin Calidris alpina, pectoral sandpipers C. melanotos, semipalmated sandpipers C. pusilla and western sandpipers C. mauri. Markers clearly differentiated all shorebird species. Estimates of population differentiation varied greatly among species (FST= 0.095a??0.685) and correlated with interspecific variation in philopatry and geographical separation of breeding populations. We assigned individuals to putative breeding locales with greater certainty in well-differentiated species than in poorly differentiated species. Our findings indicate specific phylogeographical structure varies among species, which has strong implications for conservation of habitats within migratory corridors. We suggest that RAPDs are useful in identifying geographical populations of migratory species and that molecular markers should be considered for tracking migratory birds throughout the annual cycle.

  17. Automatic classification of delphinids based on the representative frequencies of whistles.

    PubMed

    Lin, Tzu-Hao; Chou, Lien-Siang

    2015-08-01

    Classification of odontocete species remains a challenging task for passive acoustic monitoring. Classifiers that have been developed use spectral features extracted from echolocation clicks and whistle contours. Most of these contour-based classifiers require complete contours to reduce measurement errors. Therefore, overlapping contours and partially detected contours in an automatic detection algorithm may increase the bias for contour-based classifiers. In this study, classification was conducted on each recording section without extracting individual contours. The local-max detector was used to extract representative frequencies of delphinid whistles and each section was divided into multiple non-overlapping fragments. Three acoustical parameters were measured from the distribution of representative frequencies in each fragment. By using the statistical features of the acoustical parameters and the percentage of overlapping whistles, correct classification rate of 70.3% was reached for the recordings of seven species (Tursiops truncatus, Delphinus delphis, Delphinus capensis, Peponocephala electra, Grampus griseus, Stenella longirostris longirostris, and Stenella attenuata) archived in MobySound.org. In addition, correct classification rate was not dramatically reduced in various simulated noise conditions. This algorithm can be employed in acoustic observatories to classify different delphinid species and facilitate future studies on the community ecology of odontocetes. PMID:26328716

  18. Retransformation of marker-free potato for enhanced resistance against fungal pathogens by pyramiding chitinase and wasabi defensin genes.

    PubMed

    Khan, Raham Sher; Darwish, Nader Ahmed; Khattak, Bushra; Ntui, Valentine Otang; Kong, Kynet; Shimomae, Kazuki; Nakamura, Ikuo; Mii, Masahiro

    2014-09-01

    Multi-auto-transformation vector system has been one of the strategies to produce marker-free transgenic plants without using selective chemicals and plant growth regulators and thus facilitating transgene stacking. In the study reported here, retransformation was carried out in marker-free transgenic potato CV. May Queen containing ChiC gene (isolated from Streptomyces griseus strain HUT 6037) with wasabi defensin (WD) gene (isolated from Wasabia japonica) to pyramid the two disease resistant genes. Molecular analyses of the developed shoots confirmed the existence of both the genes of interest (ChiC and WD) in transgenic plants. Co-expression of the genes was confirmed by RT-PCR, northern blot, and western blot analyses. Disease resistance assay of in vitro plants showed that the transgenic lines co-expressing both the ChiC and WD genes had higher resistance against the fungal pathogens, Fusarium oxysporum (Fusarium wilt) and Alternaria solani (early blight) compared to the non-transformed control and the transgenic lines expressing either of the ChiC or WD genes. The disease resistance potential of the transgenic plants could be increased by transgene stacking or multiple transformations. PMID:24802621

  19. 3-Amino-4-hydroxybenzoic acid production from sweet sorghum juice by recombinant Corynebacterium glutamicum.

    PubMed

    Kawaguchi, Hideo; Sasaki, Kengo; Uematsu, Kouji; Tsuge, Yota; Teramura, Hiroshi; Okai, Naoko; Nakamura-Tsuruta, Sachiko; Katsuyama, Yohei; Sugai, Yoshinori; Ohnishi, Yasuo; Hirano, Ko; Sazuka, Takashi; Ogino, Chiaki; Kondo, Akihiko

    2015-12-01

    The production of the bioplastic precursor 3-amino-4-hydroxybenzoic acid (3,4-AHBA) from sweet sorghum juice, which contains amino acids and the fermentable sugars sucrose, glucose and fructose, was assessed to address the limitations of producing bio-based chemicals from renewable feedstocks. Recombinant Corynebacterium glutamicum strain KT01 expressing griH and griI derived from Streptomyces griseus produced 3,4-AHBA from the sweet sorghum juice of cultivar SIL-05 at a final concentration (1.0 g l(-1)) that was 5-fold higher than that from pure sucrose. Fractionation of sweet sorghum juice by nanofiltration (NF) membrane separation (molecular weight cut-off 150) revealed that the NF-concentrated fraction, which contained the highest concentrations of amino acids, increased 3,4-AHBA production, whereas the NF-filtrated fraction inhibited 3,4-AHBA biosynthesis. Amino acid supplementation experiments revealed that leucine specifically enhanced 3,4-AHBA production by strain KT01. Taken together, these results suggest that sweet sorghum juice is a potentially suitable feedstock for 3,4-AHBA production by recombinant C. glutamicum. PMID:26409852

  20. Protein-mediated adhesion of the dissimilatory Fe(III)-reducing bacterium Shewanella alga BrY to hydrous ferric oxide

    SciTech Connect

    Caccavo, F. Jr.

    1999-11-01

    The rate and extent of bacterial Fe(III) mineral reduction are governed by molecular-scale interactions between the bacterial cell surface and the mineral surface. These interactions are poorly understood. This study examined the role of surface proteins in the adhesion of Shewanella alga BrY to hydrous ferric oxide (HFO). Enzymatic degradation of cell surface polysaccharides had no effect on cell adhesion to HFO. The proteolytic enzymes Streptomyces griseus protease and chymotrypsin inhibited the adhesion of S. alga BrY cells to HFO through catalytic degradation of surface proteins. Trypsin inhibited S. alga BrY adhesion solely through surface-coating effects. Protease and chymotrypsin also mediated desorption of adhered S. alga BrY cells from HFO while trypsin did not mediate cell desorption. Protease removed a single peptide band that represented a protein with an apparent molecular mass of 50 kDa. Chymotrypsin removed two peptide bands that represented proteins with apparent molecular masses of 60 and 31 kDa. These proteins represent putative HGO adhesion molecules. A. alga BrY adhesion was inhibited by up to 46% when cells were cultured at sub-MICs of chloramphenicol, suggesting that protein synthesis is necessary for adhesion. Proteins extracted from the surface of S. alga BrY cells inhibited adhesion to HFO by up to 41%. A number of these proteins bound specifically to HFO, suggesting that a complex system of surface proteins mediates S. alga BrY adhesion to HFO.

  1. Cetaceans of the Atlantic Frontier, north and west of Scotland

    NASA Astrophysics Data System (ADS)

    Weir, C. R.; Pollock, C.; Cronin, C.; Taylor, S.

    2001-05-01

    Surveys carried out to the north and west of Scotland have recorded 15 species of cetacean between 1979 and 1998. These were fin whale ( Balaenoptera physalus) , sei whale ( B. borealis) , minke whale ( B. acutorostrata) , humpback whale ( Megaptera novaeangliae) , sperm whale ( Physeter macrocephalus) , northern bottlenose whale ( Hyperoodon ampullatus) , Sowerby's beaked whale ( Mesoplodon bidens) , killer whale ( Orcinus orca) , long-finned pilot whale ( Globicephala melas) , Atlantic white-sided dolphin ( Lagenorhynchus acutus) , white-beaked dolphin ( L. albirostris) , Risso's dolphin ( Grampus griseus) , bottlenose dolphin ( Tursiops truncatus) , common dolphin ( Delphinus delphis) and harbour porpoise ( Phocoena phocoena) . Atlantic white-sided dolphin was the most abundant species in the region with a total of 6317 animals recorded. Harbour porpoise was the most frequently sighted cetacean species. The geographical distribution of sightings indicate that cetacean species have varying ecological requirements, with species such as sperm whale, pilot whale and white-sided dolphin favouring deep water off the continental shelf edge, while minke whale, white-beaked dolphin and harbour porpoise were apparently limited to the continental shelf. The diversity of species recorded in the region suggests that the Atlantic Frontier is an important habitat for cetaceans.

  2. Use of In-Biofilm Expression Technology To Identify Genes Involved in Pseudomonas aeruginosa Biofilm Development†

    PubMed Central

    Finelli, Antonio; Gallant, Claude V.; Jarvi, Keith; Burrows, Lori L.

    2003-01-01

    Mature Pseudomonas aeruginosa biofilms form complex three-dimensional architecture and are tolerant of antibiotics and other antimicrobial compounds. In this work, an in vivo expression technology system, originally designed to study virulence-associated genes in complex mammalian environments, was used to identify genes up-regulated in P. aeruginosa grown to a mature (5-day) biofilm. Five unique cloned promoters unable to promote in vitro growth in the absence of purines after recovery from the biofilm environment were identified. The open reading frames downstream of the cloned promoter regions were identified, and knockout mutants were generated. Insertional mutation of PA5065, a homologue of Escherichia coli ubiB, was lethal, while inactivation of PA0240 (a porin homologue), PA3710 (a putative alcohol dehydrogenase), and PA3782 (a homologue of the Streptomyces griseus developmental regulator adpA) had no effect on planktonic growth but caused defects in biofilm formation in static and flowing systems. In competition experiments, mutants demonstrated reduced fitness compared with the parent strain, comprising less than 0.0001% of total biofilm cells after 5 days. Therefore, using in-biofilm expression technology, we have identified novel genes that do not affect planktonic growth but are important for biofilm formation, development, and fitness. PMID:12700249

  3. Evolutionary Relations of Hexanchiformes Deep-Sea Sharks Elucidated by Whole Mitochondrial Genome Sequences

    PubMed Central

    Tanaka, Keiko; Tomita, Taketeru; Suzuki, Shingo; Hosomichi, Kazuyoshi; Sano, Kazumi; Doi, Hiroyuki; Kono, Azumi; Inoko, Hidetoshi; Kulski, Jerzy K.; Tanaka, Sho

    2013-01-01

    Hexanchiformes is regarded as a monophyletic taxon, but the morphological and genetic relationships between the five extant species within the order are still uncertain. In this study, we determined the whole mitochondrial DNA (mtDNA) sequences of seven sharks including representatives of the five Hexanchiformes, one squaliform, and one carcharhiniform and inferred the phylogenetic relationships among those species and 12 other Chondrichthyes (cartilaginous fishes) species for which the complete mitogenome is available. The monophyly of Hexanchiformes and its close relation with all other Squaliformes sharks were strongly supported by likelihood and Bayesian phylogenetic analysis of 13,749 aligned nucleotides of 13 protein coding genes and two rRNA genes that were derived from the whole mDNA sequences of the 19 species. The phylogeny suggested that Hexanchiformes is in the superorder Squalomorphi, Chlamydoselachus anguineus (frilled shark) is the sister species to all other Hexanchiformes, and the relations within Hexanchiformes are well resolved as Chlamydoselachus, (Notorynchus, (Heptranchias, (Hexanchus griseus, H. nakamurai))). Based on our phylogeny, we discussed evolutionary scenarios of the jaw suspension mechanism and gill slit numbers that are significant features in the sharks. PMID:24089661

  4. Structure of an MmyB-Like Regulator from C. aurantiacus, Member of a New Transcription Factor Family Linked to Antibiotic Metabolism in Actinomycetes

    PubMed Central

    Xu, Qingping; van Wezel, Gilles P.; Chiu, Hsiu-Ju; Jaroszewski, Lukasz; Klock, Heath E.; Knuth, Mark W.; Miller, Mitchell D.; Lesley, Scott A.; Godzik, Adam; Elsliger, Marc-André; Deacon, Ashley M.; Wilson, Ian A.

    2012-01-01

    Actinomycetes are important bacterial sources of antibiotics and other secondary metabolites. Many antibiotic gene clusters are controlled by pathway-specific activators that act in response to growth conditions. Here we present the crystal structure of an MmyB-like transcription regulator MltR (PDB code 3pxp) (Caur_2278) from Chloroflexus aurantiacus, in complex with a fatty acid (myristic acid). MltR is a distant homolog of the methylenomycin activator MmyB and consists of an Xre-type N-terminal DNA-binding domain and a C-terminal ligand-binding module that is related to the Per-Arnt-Sim (PAS) domain. This structure has enabled identification of a new family of bacterial transcription factors that are distributed predominantly in actinomycetes. Bioinformatics analysis of MltR and other characterized family members suggest that they are likely associated with antibiotic and fatty acid metabolism in actinomycetes. Streptomyces coelicolor SCO4944 is a candidate as an ancestral member of the family. Its ortholog in S. griseus, SGR_6891, is induced by A-factor, a γ-butyrolactone that controls antibiotic production and development, and is adjacent to the A-factor synthase gen, afsA. The location of mltR/mmyB homologs, in particular those adjacent to less well-studied antibiotic-related genes, makes them interesting genetic markers for identifying new antibiotic genes. A model for signal-triggered DNA-binding by MltR is proposed. PMID:22844465

  5. Differences in foraging activity of deep sea diving odontocetes in the Ligurian Sea as determined by passive acoustic recorders

    NASA Astrophysics Data System (ADS)

    Giorli, Giacomo; Au, Whitlow W. L.; Neuheimer, Anna

    2016-01-01

    Characterizing the trophic roles of deep-diving odontocete species and how they vary in space and time is challenged by our ability to observe foraging behavior. Though sampling methods are limited, foraging activity of deep-diving odontocetes can be monitored by recording their biosonar emissions. Daily occurrence of echolocation clicks was monitored acoustically for five months (July-December 2011) in the Ligurian Sea (Mediterranean Sea) using five passive acoustic recorders. Detected odontocetes included Cuvier's beaked whales (Zipuhius cavirostris), sperm whales (Physeter macrocephalus), Risso's dolphins (Grampus griseus), and long-finned pilot whales (Globicephala melas). The results indicated that the foraging strategies varied significantly over time, with sperm whales switching to nocturnal foraging in late September whereas Risso's dolphins and pilot whales foraged mainly at night throughout the sampling period. In the study area, winter nights are about five hours longer than summer nights and an analysis showed that pilot whales and Risso's dolphins adjusted their foraging activity with the length of the night, foraging longer during the longer winter nights. This is the first study to show that marine mammals exhibit diurnal foraging patterns closely correlated to sunrise and sunset.

  6. Data from camera surveys identifying co-occurrence and occupancy linkages between fishers (Pekania pennanti), rodent prey, mesocarnivores, and larger predators in mixed-conifer forests.

    PubMed

    Sweitzer, Rick A; Furnas, Brett J

    2016-03-01

    These data provide additional information relevant to the frequency of fisher detections by camera traps, and single-season occupancy and local persistence of fishers in small patches of forest habitats detailed elsewhere, "Landscape Fuel Reduction, Forest Fire, and Biophysical Linkages to Local Habitat Use and Local Persistence of Fishers (Pekania pennanti) in Sierra Nevada Mixed-conifer Forests" [10]. The data provides insight on camera trap detections of 3 fisher predators (bobcat [Lynx rufus]). Coyote [Canis latrans], mountain lion [Puma concolor], 5 mesocarnivores in the same foraging guild as fishers (gray fox [Urocyon cinereoargenteus]) ringtail [Bassariscus astutus], marten [Martes americana], striped skunk [Mephitis mephitis] spotted skunk [Spilogale gracilis], and 5 Sciuridae rodents that fishers consume as prey (Douglas squirrel [Tamiasciurus douglasii]), gray squirrel [Sciurus griseus], northern flying squirrel [Glaucomys sabrinus], long-eared chipmunk [Neotamias quadrimaculatus], California ground squirrel [Spermophilus beecheyi]. We used these data to identify basic patterns of co-occurrence with fishers, and to evaluate the relative importance of presence of competing mesocarnivores, rodent prey, and predators for fisher occupancy of small, 1 km(2) grid cells of forest habitat. PMID:26937448

  7. First report of gastrocotylinean post-oncomiracidia (Platyhelminthes: Monogenoidea: Heteronchoinea) on gills of flyingfish (Exocoetidae), snapper (Lutjanidae), dolphinfish (Coryphaenidae), and amberjack (Carangidae) from the Gulf of Mexico: decoy hosts and the dilution effect.

    PubMed

    Kritsky, Delane C; Bullard, Stephen A; Bakenhaster, Micah D

    2011-09-01

    Larvae, identified as post-oncomiracidia of the suborder Gastrocotylinea (Monogenoidea), were collected from formalin-fixed gills excised from six species of marine fishes captured from the Gulf of Mexico off Mississippi and Florida: common dolphinfish, Coryphaena hippurus and pompano dolphinfish, Coryphaena equiselis (both Perciformes, Coryphaenidae); gray snapper, Lutjanus griseus (Perciformes, Lutjanidae); greater amberjack, Seriola dumerili (Perciformes, Carangidae); and Atlantic flyingfish, Cheilopogon melanurus and sailfin flyingfish, Parexocoetus hillianus (both Beloniformes and Exocoetidae). Based on a combination of diagnostic morphological features, the specimens were divided into two basic forms, each of which was further subdivided into two morphotypes. No gastrocotylinean post-oncomiracidium had been reported previously from these hosts. Of the six host species, only C. hippurus serves as a host (unconfirmed) for the adult of a gastrocotylinean species, suggesting that the recorded fishes from the Gulf of Mexico comprise dead-end hosts acting as decoys for the oncomiracidia. These comparatively non-susceptible "decoy hosts" apparently dilute the susceptible fish-host population and by intercepting infective larvae (oncomiracidia) decrease the abundance of parasites on their typical hosts. PMID:21497672

  8. Philometrid nematodes infecting fishes from the Everglades National Park, Florida, U.S.A.

    PubMed

    Moravec, Frantisek; Bakenhaster, Micah

    2010-09-01

    The following three species of the Philometridae (Nematoda: Dracunculoidea) are described from marine perciform fishes of the Everglades National Park (northern Gulf of Mexico), Florida, U.S.A.: Philometra brevispicula sp. n. (male and females) from the subcutaneous tissue of mouth of the gray snapper Lutjanus griseus (Linnaeus) (Lutjanidae), Philometroides grandipapillatus sp. n. (only females) from pectoral fin muscle of the crevalle jack Caranx hippos (Linnaeus) (Carangidae), and Caranginema americanum Moravec, Montoya-Mendoza et Salgado-Maldonado, 2008 (females) from the subcutaneous fascia of trunk muscle in crevalle jack C. hippos. Philometra brevispicula is mainly characterized by small cephalic papillae of the external circle, the absence of oesophageal teeth and the presence of small caudal projections in gravid female, markedly short spicules (45 microm) in male, and by its location in the host. Philometroides grandipapillatus differs from congeners mainly in the shape of the cephalic region (narrow, conspicuously protruding), large cephalic papillae of the external circle and the absence of caudal projections in female, and by the site of infection in the host. Caranginema americanum is for the first time recorded from the northern Gulf of Mexico. PMID:20941913

  9. Sylvatic maintenance of Borrelia burgdorferi (Spirochaetales) in Northern California: untangling the web of transmission.

    PubMed

    Brown, R N; Peot, M A; Lane, R S

    2006-07-01

    Lyme borreliosis is associated with several genospecies of Borrelia burgdorferi sensu lato (s.l.) (Spirochaetales), but human disease has been associated only with Borrelia burgdorferi sensu stricto (s.s.) Johnson, Schmid, Hyde, Steigerwalt & Brenner in the western United States. Restriction fragment length polymorphism (RFLP) analysis of rrf-rrl amplicons from 124 tick and mammalian isolates from various habitats yielded 13 RFLP patterns. Of these patterns, six were patterns previously associated either with Borrelia bissettii Postic, Marti Ras, Lane, Hendson & Baranton or Borrelia burgdorferi s.s., and the remaining seven patterns belonged to diverse and previously uncharacterized Borrelia spp. Uncharacterized Borrelia spp. were cultured most frequently from Ixodes spinipalpis Hadwen & Nuttall and California kangaroo rats, Dipodomys californicus Merriam, inhabiting grasslands, and B. bissettii from I. spinipalpis and dusky-footed woodrats, Neotoma fuscipes Baird, associated with oak woodlands or chaparral. B. burgdorferi s.s. typically was isolated from host-seeking Ixodes pacificus Cooley & Kohls collected in dense oak woodlands, woodland-grass, or redwood forests. Although some isolates of B. burgdorferi s.s. were cultured from woodrats, there was no clear association of this human pathogen with any vertebrate host. These findings, along with recent evidence indicating that the western gray squirrel, Sciurus griseus Ord, may be an important reservoir of B. burgdorferi s.s. in Californian oak woodlands, suggest that our earlier hypothesis implicating an enzootic cycle involving woodrats and I. spinipalpis is insufficient to account for observed patterns of infection in nature. PMID:16892634

  10. Introduced and native congeners use different resource allocation strategies to maintain performance during infection.

    PubMed

    Coon, Courtney A C; Brace, Amber J; McWilliams, Scott R; McCue, Marshall D; Martin, Lynn B

    2014-01-01

    Abstract Hosts can manage parasitic infections using an array of tactics, which are likely to vary contingent on coevolutionary history between the host and the parasite. Here we asked whether coping ability of congeners that differ in host-parasite coevolutionary history differed in response to experimental infections with a coccidian parasite. House sparrows (Passer domesticus) and gray-headed sparrows (Passer griseus) are sympatric and ecologically similar, but house sparrows are recent colonizers of Kenya, the site of our comparison, whereas gray-headed sparrows are native. We evaluated three variables as barometers of infection coping ability: vertical flight, pectoral muscle size, and fat score. We also measured routing of a dose of (13)C-labeled leucine, an essential amino acid, among tissues to compare resource allocation strategies in response to infection. We found that burden effects on performance were minimal in both species, but house sparrows maintained considerably higher burdens than gray-headed sparrows regardless of exposure. House sparrows also had more exogeneous leucine tracer in all tissues after 24 h, demonstrating a difference in the way the two species allocate or distribute resources. We argue that house sparrows may be maintaining larger resource reserves to mitigate costs associated with exposure and infection. Additionally, in response to increased parasite exposure, gray-headed sparrows had less leucine tracer in their spleens and more in their gonads, whereas house sparrows did not change allocation, perhaps indicating a trade-off that is not experienced by the introduced species. PMID:24940920