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1

Formation of cis-Coniferin in Cell-Free Extracts of Fagus grandifolia Ehrh Bark 1  

PubMed Central

American beech (Fagus grandifolia Ehrh) bark exclusively accumulates cis-monolignols and their glucosidic conjugates; no evidence for the accumulation of trans-monolignols has been found. The glucosyltransferase from this source exhibits a very unusual substrate specificity for cis, and not trans, monolignols. This is further evidence that cis monolignols are involved in lignin formation in these plant tissues. Preliminary evidence for the existence of a novel trans-cis monolignol isomerase was obtained, in agreement with our contention that this isomerization is not photochemically mediated. PMID:11537477

Yamamoto, Etsuo; Inciong, Ma. Estela J.; Davin, Laurence B.; Lewis, Norman G.

1990-01-01

2

Habitat Differences Influence Genetic Impacts of Human Land Use on the American Beech (Fagus grandifolia).  

PubMed

Natural reforestation after regional forest clearance is a globally common land-use sequence. The genetic recovery of tree populations in these recolonized forests may depend on the biogeographic setting of the landscape, for instance whether they are in the core or in the marginal part of the species' range. Using data from 501 individuals genotyped across 7 microsatellites, we investigated whether regional differences in habitat quality affected the recovery of genetic variation in a wind-pollinated tree species, American beech (Fagus grandifolia) in Massachusetts. We compared populations in forests that were recolonized following agricultural abandonment to those in remnant forests that have only been logged in both central inland and marginal coastal regions. Across all populations in our entire study region, recolonized forests showed limited reduction of genetic diversity as only observed heterozygosity was significantly reduced in these forests (H O = 0.520 and 0.590, respectively). Within inland region, this pattern was observed, whereas in the coast, recolonized populations exhibited no reduction in all genetic diversity estimates. However, genetic differentiation among recolonized populations in marginal coastal habitat increased (F st logged = 0.072; F st secondary = 0.249), with populations showing strong genetic structure, in contrast to inland region. These results indicate that the magnitude of recovery of genetic variation in recolonized populations can vary at different habitats. PMID:25138571

Lumibao, Candice Y; McLachlan, Jason S

2014-01-01

3

Comparisons of protein profiles of beech bark disease resistant and susceptible American beech (Fagus grandifolia)  

PubMed Central

Background Beech bark disease is an insect-fungus complex that damages and often kills American beech trees and has major ecological and economic impacts on forests of the northeastern United States and southeastern Canadian forests. The disease begins when exotic beech scale insects feed on the bark of trees, and is followed by infection of damaged bark tissues by one of the Neonectria species of fungi. Proteomic analysis was conducted of beech bark proteins from diseased trees and healthy trees in areas heavily infested with beech bark disease. All of the diseased trees had signs of Neonectria infection such as cankers or fruiting bodies. In previous tests reported elsewhere, all of the diseased trees were demonstrated to be susceptible to the scale insect and all of the healthy trees were demonstrated to be resistant to the scale insect. Sixteen trees were sampled from eight geographically isolated stands, the sample consisting of 10 healthy (scale-resistant) and 6 diseased/infested (scale-susceptible) trees. Results Proteins were extracted from each tree and analysed in triplicate by isoelectric focusing followed by denaturing gel electrophoresis. Gels were stained and protein spots identified and intensity quantified, then a statistical model was fit to identify significant differences between trees. A subset of BBD differential proteins were analysed by mass spectrometry and matched to known protein sequences for identification. Identified proteins had homology to stress, insect, and pathogen related proteins in other plant systems. Protein spots significantly different in diseased and healthy trees having no stand or disease-by-stand interaction effects were identified. Conclusions Further study of these proteins should help to understand processes critical to resistance to beech bark disease and to develop biomarkers for use in tree breeding programs and for the selection of resistant trees prior to or in early stages of BBD development in stands. Early identification of resistant trees (prior to the full disease development in an area) will allow forest management through the removal of susceptible trees and their root-sprouts prior to the onset of disease, allowing management and mitigation of costs, economic impact, and impacts on ecological systems and services. PMID:23317283

2013-01-01

4

Misidentification of tansy, Tanacetum macrophyllum, as yarrow, Achillea grandifolia: a health risk or benefit?  

PubMed

Tansy, Tanacetum macrophyllum (Waldst. & Kit.) Sch. Bip., is often misidentified by herb collectors as yarrow, Achillea grandifolia Friv. With the former, cases of poisoning induced by its ingestion are well documented, but the latter is widely used for ethnopharmacological purposes. The aim of this study was to estimate, based on the volatile metabolite profiles of the two species, the potential health risk connected with their misidentification. GC and GC-MS analysis of the essential oils hydrodistilled using a Clevenger-type apparatus from A. grandifolia, T. macrophyllum, and two plant samples (reputedly of A. grandifolia, but in fact mixtures of A. grandifolia and T. macrophyllum) obtained from a local market, resulted in the identification of 215 different compounds. The main constituents of A. grandifolia oil were ascaridole (15.5%), alpha-thujone (7.5%), camphor (15.6%), borneol (5.2%) and (Z)-jasmone (6.4%), and of T. macrophyllum oil, 1,8-cineole (8.6%), camphor (6.4%), borneol (9.1%), isobornyl acetate (9.5%), copaborneol (4.2%) and gamma-eudesmol (6.2%). The compositions of the oils extracted from the samples obtained from the market were intermediate to those of A. grandifolia and T. macrophyllum. Significant differences in the corresponding volatile profiles and the literature data concerning the known activities of the pure constituents of the oils, suggested that the pharmacological action of the investigated species (or their unintentional mixtures) would be notably different. It seems, however, that misidentification of T. macrophyllum as A. grandifolia does not represent a health risk and that the absence of the toxic alpha-thujone from T. macrophyllum oil may in fact be regarded as a benefit. PMID:20184036

Radulovi?, Niko S; Blagojevi?, Polina D; Skropeta, Danielle; Zarubica, Aleksandra R; Zlatkovi?, Bojan K; Pali?, Radosav M

2010-01-01

5

Seasonal variations of symbiotic ultrastructure and relationships of two natural ectomycorrhizae of beech ( Fagus sylvatica \\/ Lactarius blennius var. viridis and Fagus sylvatica \\/ Lactarius subdulcis )  

Microsoft Academic Search

This study concerned two perennial ectomycorrhizae of beech: Fagus sylvatica L.\\/Lactarius blennius var. viridis and Fagus sylvatica L.\\/Lactarius subdulcis, collected in a natural forest site. Nutritional exchanges existing between beech roots and fungi were evaluated over a seasonal cycle by studying the variations of ultrastructure, polyphosphate and nitrogenous granules and glycogen content (periodic acid thiocarbohydrazide silver test). The acid phosphatase

P. Genet; A. Prevost; J. C. Pargney

2000-01-01

6

Original article Restoring catalase activity in Staphylococcus aureus subsp.  

E-print Network

Original article Restoring catalase activity in Staphylococcus aureus subsp. anaerobius leads; accepted 15 February 2010) Abstract � Staphylococcus aureus subsp. anaerobius, a microaerophilic / pathogenesis / catalase / abscess disease / sheep 1. INTRODUCTION Staphylococcus aureus subsp. anaerobius

Paris-Sud XI, Université de

7

Wieferich, D, D. B. Hayes, D. McCullough, and N. Schwalm. In press. Distribution of American Beech (Fagus grandifolia) and Beech Scale (Cryptococcus fagisuga Lind.) in Michigan from 2005 to 2009.  

E-print Network

of the Stronach Dam Removal on Fish in the Pine River, Manistee County, Michigan. Transactions of the American. Northern Journal of Applied Forestry Hansen, J. and D. B. Hayes. In press. Long-Term Implications of Dam Removal for Macroinvertebrate Communities In Michigan and Wisconsin Rivers, United States. River Research

8

Lactobacillus plantarum subsp. argentoratensis subsp. nov., isolated from vegetable matrices.  

PubMed

Fourteen strains isolated from vegetable sources and identified as belonging to Lactobacillus plantarum presented an atypical pattern of amplification with a species-specific multiplex-PCR assay. Phylogenetic analysis of two protein-encoding genes, recA (encoding the recombinase A protein) and cpn60 (encoding the GroEL chaperonin), as well as phenotypic and genomic traits revealed a homogeneous group of very closely related strains for which subspecies status is proposed, with the name Lactobacillus plantarum subsp. argentoratensis. The type strain is DKO 22(T) (=CIP 108320(T)=DSM 16365(T)). PMID:16014493

Bringel, Franoise; Castioni, Anna; Olukoya, Daniel K; Felis, Giovanna E; Torriani, Sandra; Dellaglio, Franco

2005-07-01

9

Phylogeography of Francisella tularensis subsp. holarctica, Europe  

PubMed Central

Francisella tularensis subsp. holarctica isolates from Austria, Germany, Hungary, Italy, and Romania were placed into an existing phylogeographic framework. Isolates from Italy were assigned to phylogenetic group B.FTNF00200; the other isolates, to group B.13. Most F. tularensis subsp. holarctica isolates from Europe belong to these 2 geographically segregated groups. PMID:22305204

Gyuranecz, Miklos; Birdsell, Dawn N.; Splettstoesser, Wolf; Seibold, Erik; Beckstrom-Sternberg, Stephen M.; Makrai, Laszlo; Fodor, Laszlo; Fabbi, Massimo; Vicari, Nadia; Johansson, Anders; Busch, Joseph D.; Vogler, Amy J.; Keim, Paul

2012-01-01

10

Clavibacter michiganensis subsp. phaseoli subsp. nov., pathogenic in bean.  

PubMed

A yellow Gram-reaction-positive bacterium isolated from bean seeds (Phaseolus vulgaris L.) was identified as Clavibacter michiganensis by 16S rRNA gene sequencing. Molecular methods were employed in order to identify the subspecies. Such methods included the amplification of specific sequences by PCR, 16S amplified rDNA restriction analysis (ARDRA), RFLP and multilocus sequence analysis as well as the analysis of biochemical and phenotypic traits including API 50CH and API ZYM results. The results showed that strain LPPA 982T did not represent any known subspecies of C. michiganensis. Pathogenicity tests revealed that the strain is a bean pathogen causing a newly identified bacterial disease that we name bacterial bean leaf yellowing. On the basis of these results, strain LPPA 982T is regarded as representing a novel subspecies for which the name Clavibacter michiganensis subsp. phaseoli subsp. nov. is proposed. The type strain is LPPA 982T (=CECT 8144T=LMG 27667T). PMID:24554636

Gonzlez, Ana J; Trapiello, Estefana

2014-05-01

11

Identification of Mycobacterium avium subsp. hominissuis Isolated From Drinking Water  

EPA Science Inventory

Mycobacterium avium (MA) is divided into four subspecies based primarily on host-range and consists of MA subsp. avium (birds), MA subsp. silvaticum (wood pigeons), MA subsp. paratuberculosis (broad, poorly-defined host range), and the recently described MA subsp. hominissuis (hu...

12

Effects of fertilization on the vascular ground vegetation of European beech (Fagus sylvatica L.) and sessile oak (Quercus petraea (Matt.) Lieb.) stands  

E-print Network

pubescens Fagus sylvatica Holcus lanatus Picea abies Poa nemoralis Poa trivialis Quercus sp. Rubuspubescens Fagus sylvatica Holcus lanatus Lapsana communis Picea abies Poa nemoralis Poa trivialis Quercus sp. Rubus

Misson, Laurent

2001-01-01

13

Enterobacter hormaechei subsp. oharae subsp. nov., E. hormaechei subsp. hormaechei comb. nov., and E. hormaechei subsp. steigerwaltii subsp. nov., Three New Subspecies of Clinical Importance  

PubMed Central

Six species and six additional genovars are combined within the so-called Enterobacter cloacae complex, with one of them being the species Enterobacter hormaechei. In a recent population genetic study, two genetic clusters were found in close phylogenetic proximity to the genetic cluster of E. hormaechei. In order to prove the hypothesis that these three genetic clusters belong to the same species, we performed cross-hybridization experiments in microplates with DNAs of representatives of each genetic cluster. The close phylogenetic relationship among the clusters was reflected by their relatively low ?Tm values, ranging from 0.3 to 4.8, confirming the hypothesis that the clusters are parts of the same species. These clusters can be distinguished from the other species of the E. cloacae complex, which have ?Tm values of 5.6 to 10.3. Forty-eight E. hormaechei strains from the different genetic clusters were phenotypically characterized with 129 biochemical tests. In this way, E. hormaechei could be differentiated from the other species of the E. cloacae complex because it tests negative in the 3-hydroxy-butyrate test. The three genetic clusters of E. hormaechei could also be differentiated from each other by using phenotypic tests. Hence, we propose three new subspecies of E. hormaechei corresponding to genetic clusters VI, VII, and VIII of the E. cloacae complex. E. hormaechei subsp. hormaechei comb. nov. corresponds to the original species description, as it gives negative results for the adonitol, d-arabitol, d-sorbitol, and d-melibiose tests and a positive result for the dulcitol test. E. hormaechei subsp. oharae subsp. nov. gives negative results for the dulcitol, adonitol, and d-arabitol tests and positive results for the d-sorbitol and d-melibiose tests. E. hormaechei subsp. steigerwaltii subsp. nov. gives a negative result for the dulcitol test and positive results for the adonitol, d-arabitol, d-sorbitol, and d-melibiose tests. Among the members of the E. cloacae complex, E. hormaechei seems to be the species most frequently recovered from clinical specimens. PMID:16000451

Hoffmann, Harald; Stindl, Sibylle; Ludwig, Wolfgang; Stumpf, Anita; Mehlen, Andre; Monget, Daniel; Pierard, Denis; Ziesing, Stefan; Heesemann, Jurgen; Roggenkamp, Andreas; Schleifer, Karl H.

2005-01-01

14

Original article Mycoplasma mycoides subsp. mycoides SC  

E-print Network

Original article Mycoplasma mycoides subsp. mycoides SC identification by PCR in sperm of seminal) diagnosis for the detection and identification of Mycoplasma, we investigated mycoplasmas contaminating was neg- ative. Furthermore, we have investigated mycoplasmas isolated from semen of healthy breeding

Paris-Sud XI, Université de

15

Leaf and stem CO uptake in the three subfamilies of the Cactaceae. [Pereskia aculeata; Pereskia grandifolia; Maihuenia poeppigii; Carnegiea gigantea; Ferocactus acanthodes; Coryphantha vivipara; Mammillaria dioica; Opuntia ficus-inidica; Pereskiopsis porteri; Quiabentia chacoensis; Austrocylindropuntia subulata  

Microsoft Academic Search

Net CO uptake over 24-hour periods was examined for the leaves and for the stems of 11 species of cacti representing all three subfamilies. For Pereskia aculeata, Pereskia grandifolia, and Maihuenia poeppigii (subfamily Pereskioideae), all the net shoot CO uptake was by the leaves and during the daytime. In contrast, for the leafless species Carnegiea gigantea, Ferocactus acanthodes, Coryphantha vivipara,

P. S. Nobel; T. L. Hartsock

1986-01-01

16

Differential temperature dependencies of antioxidative enzymes in two contrasting species: Fagus sylvatica and Coleus blumei  

Microsoft Academic Search

In order to characterise the sensitivity of antioxidative systems to temperature-induced oxidative stress, two species (Coleus blumei and Fagus sylvatica, L.) representative of environments with contrasting temperature characteristics have been exposed to low or high temperatures of 10 or 35C, respectively. Beech leaves were harvested in light and darkness. Coleus leaves were separated into green and white leaf tissue. The

Detlef Peltzer; Erwin Dreyer; Andrea Polle

2002-01-01

17

Campylobacter fetus subsp. testudinum subsp. nov., isolated from humans and reptiles.  

PubMed

A polyphasic study was undertaken to determine the taxonomic position of 13 Campylobacter fetus-like strains from humans (n?=?8) and reptiles (n?=?5). The results of matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) MS and genomic data from sap analysis, 16S rRNA gene and hsp60 sequence comparison, pulsed-field gel electrophoresis, amplified fragment length polymorphism analysis, DNA-DNA hybridization and whole genome sequencing demonstrated that these strains are closely related to C. fetus but clearly differentiated from recognized subspecies of C. fetus. Therefore, this unique cluster of 13 strains represents a novel subspecies within the species C. fetus, for which the name Campylobacter fetus subsp. testudinum subsp. nov. is proposed, with strain 03-427(T) (?=?ATCC BAA-2539(T)?=?LMG 27499(T)) as the type strain. Although this novel taxon could not be differentiated from C. fetus subsp. fetus and C. fetus subsp. venerealis using conventional phenotypic tests, MALDI-TOF MS revealed the presence of multiple phenotypic biomarkers which distinguish Campylobacter fetus subsp. testudinum subsp. nov. from recognized subspecies of C. fetus. PMID:24899653

Fitzgerald, Collette; Tu, Zheng Chao; Patrick, Mary; Stiles, Tracy; Lawson, Andy J; Santovenia, Monica; Gilbert, Maarten J; van Bergen, Marcel; Joyce, Kevin; Pruckler, Janet; Stroika, Steven; Duim, Birgitta; Miller, William G; Loparev, Vladimir; Sinnige, Jan C; Fields, Patricia I; Tauxe, Robert V; Blaser, Martin J; Wagenaar, Jaap A

2014-09-01

18

Identification and characterization of differentially expressed genes from Fagus sylvatica roots after infection with Phytophthora citricola  

Microsoft Academic Search

Phytophthora species are major plant pathogens infecting herbaceous and woody plants including European beech, the dominant or co-dominant\\u000a tree in temperate Europe and an economically important species. For the analysis of the interaction of Phytophthora citricola with Fagus sylvatica suppression subtractive hybridization was used to isolate transcripts induced during infection and 1,149 sequences were generated.\\u000a Hybridizations with driver and tester

Katja Schlink

2009-01-01

19

Biocontrol of Pectobacterium carotovorum subsp. carotovorum using bacteriophage PP1.  

PubMed

Pectobacterium carotovorum subsp. carotovorum (formerly Erwinia carotovora subsp. carotovora) is a plant pathogen that causes soft rot and stem rot diseases in several crops, including Chinese cabbage, potato, and tomato. To control this bacterium, we isolated a bacteriophage, PP1, with lytic activity against P. carotovorum subsp. carotovorum. Transmission electron microscopy revealed that the PP1 phage belongs to the Podoviridae family of the order Caudovirales, which exhibit icosahedral heads and short non-contractile tails. PP1 phage showed high specificity for P. carotovorum subsp. carotovorum, and several bacteria belonging to different species and phyla were resistant to PP1. This phage showed rapid and strong lytic activity against its host bacteria in liquid medium and was stable over a broad range of pH values. Disease caused by P. carotovorum subsp. carotovorum was significantly reduced by PP1 treatment. Overall, PP1 bacteriophage effectively controls P. carotovorum subsp. carotovorum. PMID:23727798

Lim, Jeong-A; Jee, Samnyu; Lee, Dong Hwan; Roh, Eunjung; Jung, Kyusuk; Oh, Changsik; Heu, Sunggi

2013-08-01

20

Fluorescence In Situ Hybridization Using Peptide Nucleic Acid Probes for Rapid Detection of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. paratuberculosis in Potable-Water Biofilms  

Microsoft Academic Search

Here, we present for the first time a high-affinity peptide nucleic acid (PNA) oligonucleotide sequence for detecting Mycobacterium avium bacteria, including the opportunistically pathogenic subspecies M. avium subsp. avium, M. avium subsp. paratuberculosis, and M. avium subsp. silvaticum, by the fluorescence in situ hybrid- ization (FISH) method. There is evidence that M. avium subsp. avium especially is able to survive

Markku J. Lehtola; Eila Torvinen; Ilkka T. Miettinen; C. William Keevil

2006-01-01

21

Deoxyribonucleic Acid Homology Studies of Lactobacillus casei, Lactobacillus paracasei sp. nov., subsp. paracasei and subsp. tolerans, and Lactobacillus rhamnosus sp. nov., comb. nov  

Microsoft Academic Search

Deoxyribonucleic acid (DNA)-DNA hybridizations were performed on strains of Lactobacillus casei. Our results indicate that this species as presently constituted is genomically very heterogeneous. The majority of strains designated L. casei subsp. casei, together with members of L. casei subsp. alactosus, L. casei subsp. pseudoplantarum, and L. casei subsp. tolerans, exhibited high levels of DNA relatedness with each other but

MATTHEW D. COLLINS; BRIAN A. PHILLIPS; PAOLO ZANONI

22

Phylogeny of Photorhabdus and Xenorhabdus based on universally conserved protein-coding sequences and implications for the taxonomy of these two genera. Proposal of new taxa: X. vietnamensis sp. nov., P. luminescens subsp. caribbeanensis subsp. nov., P. luminescens subsp. hainanensis subsp. nov., P. temperata subsp. khanii subsp. nov., P. temperata subsp. tasmaniensis subsp. nov., and the reclassification of P. luminescens subsp. thracensis as P. temperata subsp. thracensis comb. nov.  

PubMed

We used the information from a set of concatenated sequences from four genes (recA, gyrB, dnaN and gltX) to investigate the phylogeny of the genera Photorhabdus and Xenorhabdus (entomopathogenic bacteria associated with nematodes of the genera Heterorhabditis and Steinernema, respectively). The robustness of the phylogenetic tree obtained by this multigene approach was significantly better than that of the tree obtained by a single gene approach. The comparison of the topologies of single gene phylogenetic trees highlighted discrepancies which have implications for the classification of strains and new isolates; in particular, we propose the transfer of Photorhabdus luminescens subsp. thracensis to Photorhabdus temperata subsp. thracensis comb. nov. (type strain CIP 108426T =DSM 15199T). We found that, within the genus Xenorhabdus, strains or isolates that shared less than 97 % nucleotide identity (NI), calculated on the concatenated sequences of the four gene fragments (recA, gyrB, dnaN and gltX) encompassing 3395 nucleotides, did not belong to the same species. Thus, at the 97% NI cutoff, we confirm the current 20 species of the genus Xenorhabdus and propose the description of a novel species, Xenorhabdus vietnamensis sp. nov. (type strain VN01T =CIP 109945T =DSM 22392T). Within each of the three current species of the genus Photorhabdus, P. asymbiotica, P. luminescens and P. temperata, strains or isolates which shared less than 97% NI did not belong to the same subspecies. Comparisons of the four gene fragments plus the rplB gene fragment analysed separately led us to propose four novel subspecies: Photorhabdus luminescens subsp. caribbeanensis subsp. nov. (type strain HG29T =CIP 109949T =DSM 22391T), P. luminescens subsp. hainanensis subsp. nov. (type strain C8404T = CIP 109946T =DSM 22397T), P. temperata subsp. khanii subsp. nov. (type strain C1T =NC19(T) =CIP 109947T =DSM 3369T), and P. temperata subsp. tasmaniensis subsp. nov. (type strain T327T =CIP 109948T =DSM 22387T). PMID:19783607

Tailliez, Patrick; Laroui, Christine; Ginibre, Nadge; Paule, Armelle; Pags, Sylvie; Boemare, Nol

2010-08-01

23

Bartonella vinsonii subsp. arupensis in Humans, Thailand  

PubMed Central

We identified Bartonella vinsonii subsp. arupensis in pre-enriched blood of 4 patients from Thailand. Nucleotide sequences for transfer-messenger RNA gene, citrate synthase gene, and the 16S23S rRNA internal transcribed spacer were identical or closely related to those for the strain that has been considered pathogenic since initially isolated from a human in Wyoming, USA. PMID:22607728

Kosoy, Michael Y.; Diaz, Maureen H.; Winchell, Jonas; Baggett, Henry; Maloney, Susan A.; Boonmar, Sumalee; Bhengsri, Saithip; Sawatwong, Pongpun; Peruski, Leonard F.

2012-01-01

24

Use of PCR-Based Methods for Rapid Differentiation of Lactobacillus delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis  

Microsoft Academic Search

Two PCR-based methods, specific PCR and randomly amplified polymorphic DNA PCR (RAPD-PCR), were used for rapid and reliable differentiation of Lactobacillus delbrueckii subsp. bulgaricus and L. delbrueckii subsp. lactis. PCR with a single combination of primers which targeted the proline iminopeptidase (pepIP) gene of L. delbrueckii subsp. bulgaricus allowed amplification of genomic fragments specific for the two subspecies when either

SANDRA TORRIANI; GIACOMO ZAPPAROLI; FRANCO DELLAGLIO

1999-01-01

25

Genome Sequence of Salmonella enterica subsp. enterica Strain Durban.  

PubMed

We report the genome sequence of Salmonella enterica subsp. enterica strain Durban, isolated from a patient with salmonellosis and typhoid fever. The strain is closely related to S.enterica subsp. enterica strain P125109 but differs in loss of the SE20 prophage and acquisition of a prophage similar to ELPhiS. PMID:24812224

Russell, Daniel A; Bowman, Charles A; Hatfull, Graham F

2014-01-01

26

Composition and antimicrobial activity of the essential oils of Achillea nobilis L. subsp. sipylea and subsp. neilreichii  

Microsoft Academic Search

plant materials are not known in some studies. The present study was carried out for the first time to determine the chemical composition of the essential oils of A. nobilis subsp. sipylea and A. nobilis subsp. neilreichii collected from Turkey, and their antimicrobial activities were tested against eight Gram positive and Gram negative bacteria strains and Candida albicans. The percentage

C. Karamenderes; N. U. Karabay Yavasoglu; U. Zeybek

2007-01-01

27

Discrimination of Mycobacterium abscessus subsp. massiliense from Mycobacterium abscessus subsp. abscessus in Clinical Isolates by Multiplex PCR  

PubMed Central

The rapidly growing mycobacterium M. abscessus sensu lato is the causative agent of emerging pulmonary and skin diseases and of infections following cosmetic surgery and postsurgical procedures. M. abscessus sensu lato can be divided into at least three subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. Clinical isolates of rapidly growing mycobacteria were previously identified as M. abscessus by DNA-DNA hybridization. More than 30% of these 117 clinical isolates were differentiated as M. abscessus subsp. massiliense using combinations of multilocus genotyping analyses. A much more cost-effective technique to distinguish M. abscessus subsp. massiliense from M. abscessus subsp. abscessus, a multiplex PCR assay, was developed using the whole-genome sequence of M. abscessus subsp. massiliense JCM15300 as a reference. Several primer sets were designed for single PCR to discriminate between the strains based on amplicons of different sizes. Two of these single-PCR target sites were chosen for development of the multiplex PCR assay. Multiplex PCR was successful in distinguishing clinical isolates of M. abscessus subsp. massiliense from samples previously identified as M. abscessus. This approach, which spans whole-genome sequencing and clinical diagnosis, will facilitate the acquisition of more-precise information about bacterial genomes, aid in the choice of more relevant therapies, and promote the advancement of novel discrimination and differential diagnostic assays. PMID:24197885

Sekizuka, Tsuyoshi; Fukano, Hanako; Sakakibara, Yumi; Takeuchi, Fumihiko; Wada, Shinpei; Ishii, Norihisa; Makino, Masahiko; Hoshino, Yoshihiko

2014-01-01

28

Photorhabdus luminescens subsp. noenieputensis subsp. nov., a symbiotic bacterium associated with a novel Heterorhabditis species related to Heterorhabditis indica.  

PubMed

The bacterial symbiont AM7(T), isolated from a novel entomopathogenic nematode species of the genus Heterorhabditis, displays the main phenotypic traits of the genus Photorhabdus and is highly pathogenic to Galleria mellonella. Phylogenetic analysis based on a multigene approach (16S rRNA, recA, gyrB, dnaN, gltX and infB) confirmed the classification of isolate AM7(T) within the species Photorhabdus luminescens and revealed its close relatedness to Photorhabdus luminescens subsp. caribbeanensis, P. luminescens subsp. akhurstii and P. luminescens subsp. hainanensis. The five concatenated protein-encoding sequences (4197 nt) of strain AM7(T) revealed 95.8, 95.4 and 94.9?% nucleotide identity to sequences of P. luminescens subsp. caribbeanensis HG29(T), P. luminescens subsp. akhurstii FRG04(T) and P. luminescens subsp. hainanensis C8404(T), respectively. These identity values are less than the threshold of 97?% proposed for classification within one of the existing subspecies of P. luminescens. Unlike other strains described for P. luminescens, strain AM7(T) produces acid from adonitol, sorbitol and xylitol, assimilates xylitol and has no lipase activity on medium containing Tween 20 or 60. Strain AM7(T) is differentiated from P. luminescens subsp. caribbeanensis by the assimilation of N-acetylglucosamine and the absence of haemolytic activity. Unlike P. luminescens subsp. akhurstii, strain AM7(T) does not assimilate mannitol, and it is distinguished from P. luminescens subsp. hainanensis by the assimilation of trehalose and citrate, the inability to produce indole from tryptophan and the presence of acetoin production and urease activity. Strain AM7(T) (?=?ATCC BAA-2407(T) ?=?DSM 25462(T)) belongs to a novel subspecies, and is proposed as the type strain of Photorhabdus luminescens subsp. noenieputensis sp. nov. PMID:22984141

Ferreira, Tiarin; van Reenen, Carol; Pags, Sylvie; Tailliez, Patrick; Malan, Antoinette P; Dicks, Leon M T

2013-05-01

29

Reclassification of Leuconostoc gasicomitatum as Leuconostoc gelidum subsp. gasicomitatum comb. nov., description of Leuconostoc gelidum subsp. aenigmaticum subsp. nov., designation of Leuconostoc gelidum subsp. gelidum subsp. nov. and emended description of Leuconostoc gelidum.  

PubMed

In the present study we investigated the taxonomic status of 20 lactic acid bacteria (LAB) originating from packaged meat. On the basis of 16S rRNA gene sequence similarity, these strains were shown to belong to the genus Leuconostoc with Leuconostoc gelidum, Leuconostoc inhae and Leuconostoc gasicomitatum as the closest phylogenetic relatives. The novel strains shared more than 70?% DNA-DNA relatedness with type and reference strains of both L. gelidum and L. gasicomitatum. The DNA-DNA relatedness values between L. gelidum type and reference strains and L. gasicomitatum type and reference strains were also above 70?%, showing that all these strains belonged to the same species. Sequence analyses of concatenated atpA, pheS, and rpoA genes demonstrated that the novel strains as well as type and reference strains of L. gelidum and L. gasicomitatum are phylogenetically closely related, but form three clearly separated subgroups. Numerical analysis of HindIII ribopatterns and phenotypic tests supported this subdivision. Based on the data presented in this study, we propose to reclassify Leuconostoc gasicomitatum as Leuconostoc gelidum subsp. gasicomitatum comb. nov. (type strain, LMG 18811(T)?=?DSM 15947(T)). The novel strains isolated in the present study represent a novel subspecies, for which the name Leuconostoc gelidum subsp. aenigmaticum subsp. nov. is proposed, with POUF4d(T) (?=?LMG 27840(T)?=?DSM 19375(T)) as the type strain. The proposal of these two novel subspecies automatically creates the subspecies Leuconostoc gelidum subsp. gelidum subsp. nov. (type strain, NCFB 2775(T)?=?DSM 5578(T)). An emended description of Leuconostoc gelidum is also provided. PMID:24431060

Rahkila, Riitta; De Bruyne, Katrien; Johansson, Per; Vandamme, Peter; Bjrkroth, Johanna

2014-04-01

30

New Phenolics from Linum mucronatum subsp. orientale  

PubMed Central

Introduction: Lignans and flavonoids are widely distributed phenolics in the plant kingdom. Aryltetralin type lignans (podophyllotoxin derivatives) as the major secondary metabolites of Linum species play an important role in the production of chemotherapy drugs. In the present study, lignans and flavonoid glycosides from aerial parts of Linum mucronatum subsp. orientale were isolated and identified. Methods: The phytochemical investigation has been carried out on Hexane, DCM and MeOH extracts of the plant. Separation of chemical constituents was done using different chromatography (CC, prep-TLC, GC/MS and HPLC) methods. The major compounds of dichloromethane (DCM) and methanol extracts were isolated and their structures were elucidated using co-chromatography in the presence of known lignans, HPLC and NMR techniques. Results: Our results showed that podophyllotoxin and 6-MeO-?- peltatin, as new compound, are the major lignans of the DCM extract of L. mucronatum subsp. orientale. Two new flavonoid glycosides were also elucidated in the methanolic extract. Conclusion: The DCM and methanol extracts of L. mucronatum were found to contain aryltetralin-type lignans and flavonoids. The occurrence of 6-MeO-?- peltatin and flavonoids in L. mucronatum has been reported for the first time. PMID:25337464

Zare, Khadijeh; Movafeghi, Ali; Mohammadi, Sayed Abolghasem; Asnaashari, Solmaz; Nazemiyeh, Hossein

2014-01-01

31

Growth of Fagus in transition zones of forest and soil on the western slope of Mt. Chokai, northern Japan  

NASA Astrophysics Data System (ADS)

A wide transition zone for forest structure is expected to distribute on the gentle slope of western side of Mt. Chokai ,Yamagata prefecture, northern Japan (N39 05'57", E14002'55"). The annual mean temperature and total precipitation at summit (2,059 m asl.) are 0.5 C and 3,285mm, respectively. The parent materials of the soils are weathered Andesite associated with non-tephric loess deposits transported from continental China. Representative sites were selected in forests of Quercus mongolica and Fagus crenata to examine characteristics of transition zones of vegetation and soil in the western slope of Mt. Chokai with concern on the growth of Fagus in transition zones. Surveys on vegetation profile and projection diagram of canopy for each site (10-10m plots) were carried out in 7 sites selected along altitudinal sequence on the western slope of Mt. Chokai; Ch1-7: 550-1,100m asl.. Growth rate of Fagus was estimated by the measurement of tree rings from increment core samples. Timber volume of Fagus at each point was calculated based on diameter of breast height; DBH as an indicator of tree biomass. Soil profiles were observed at the above 7 sites and soil samples were collected from each horizon. As for soil analyses, soil pH (H2O, KCl, NaF) values were measured by the glass electrode method in the suspension mixture of soil with a 2.5 times volume of H2O or 1N KCl and 50 times volume of 4% NaF. Pyrophosphate, acid oxalate and dithionite-citrate extractable Al (Alp, Alo, Ald), Fe (Feo, Fed) and Si (Sio, Sid) were measured by ICP-AES. The content of exchangeable Al (AlEX) was obtained by titration of extract with 1N KCl. Sclerotia formed by species of Cenococcum, ectomycorrhizal fungi, were collected for grains of diameter larger than 0.5mm from wet samples. Sclerotia content was obtained by weight (mg g-1 soil). Due to intensive base leaching under extremely high precipitation and the mineralogical properties, Ah and Ae horizons of all profiles had low soil pH values (3.4-4.6 in H2O) and a high content of exchangeable Al (0.20-1.09g kg-1 soil), which could restrict nutrient uptake and growth of trees. From observation of forest structures of each site, transition zone was approximately 750m by horizontal distance including Ch3-5 (710-780m asl.). The DBH of Fagus was more than 45cm at Ch3,4, and the timber volume of Fagus was the largest at Ch3, followed by Ch4, and the smallest at Ch7, followed by Ch6. Among the entire 7 sites, the growth rate of Fagus was the largest at Ch3 where soil pH value was above 4.0 and exchangeable Al content was relatively low. The oldest and highest Fagus was observed at Ch4, where content of exchangeable Al was high (1.0 g kg-1) . While, Fagus at Ch3,5 and 7 had almost same age. Sclerotia content in soils was much larger in transition zone (Ch3,4) than in podzolic soils (Ch6,7) beneath the dwarfed Fagus forest. The activity of mycorrhizae was suggested to be one of the important factors for the growth of Fagus in transition zone.

Kato, S.; Watanabe, M.

2012-04-01

32

Genetic Diversity of Pectobacterium carotovorum subsp. brasiliensis Isolated in Korea  

PubMed Central

The plant pathogenic bacterial genus Pectobacteirum consists of heterogeneous strains. The P. carotovorum species is a complex strain showing divergent characteristics, and a new subspecies named P. carotovorum subsp. brasiliensis has been identified recently. In this paper, we re-identified the P. carotovorum subsp. brasiliensis isolates from those classified under the subspecies carotovorum and newly isolated P. carotovorum subsp. brasiliensis strains. All isolates were able to produce plant cell-wall degrading enzymes such as pectate lyase, polygalacturonase, cellulase and protease. We used genetic and biochemical methods to examine the diversity of P. carotovorum subsp. brasiliensis isolates, and found genetic diversity within the brasiliensis subsp. isolates in Korea. The restriction fragment length polymorphism analysis based on the recA gene revealed a unique pattern for the brasiliensis subspecies. The Korean brasiliensis subsp. isolates were divided into four clades based on pulsed-field gel electrophoresis. However, correlations between clades and isolated hosts or year could not be found, suggesting that diverse brasiliensis subsp. isolates existed. PMID:25288994

Lee, Dong Hwan; Kim, Jin-Beom; Lim, Jeong-A; Han, Sang-Wook; Heu, Sunggi

2014-01-01

33

Frequency of inversions affects senescence phenology of Acer pseudoplatanus and Fagus sylvatica  

NASA Astrophysics Data System (ADS)

In mountainous regions, inversion situations with cold-air pools in the valleys occur frequently, especially in fall and winter. With the accumulation of inversion days, trees in lower elevations experience lower temperature sums than those in middle elevations. In a two-year observational study, deciduous trees, such as Acer pseudoplatanus and Fagus sylvatica, on altitudinal transects responded in their fall leaf senescence phenology. Phenological phases were advanced and senescence duration was shortened by the cold temperatures in the valley. This effect was more distinct for late phases than for early phases since they experienced more inversion days. The higher the inversion frequency, the stronger the signal was. Acer pseudoplatanus proved to be more sensitive to cold temperatures compared to Fagus sylvatica. We conclude that cold-air pools have a considerable impact on the vegetation period of deciduous trees. Considering this effect, trees in the mid hillside slopes gain advantages compared to lower elevations. Our findings will help to improve knowledge about ecological drivers and responses in mountainous forest ecosystems.

Schuster, Christina; Kirchner, Manfred; Jakobi, Gert; Menzel, Annette

2014-05-01

34

Frequency of inversions affects senescence phenology of Acer pseudoplatanus and Fagus sylvatica.  

PubMed

In mountainous regions, inversion situations with cold-air pools in the valleys occur frequently, especially in fall and winter. With the accumulation of inversion days, trees in lower elevations experience lower temperature sums than those in middle elevations. In a two-year observational study, deciduous trees, such as Acer pseudoplatanus and Fagus sylvatica, on altitudinal transects responded in their fall leaf senescence phenology. Phenological phases were advanced and senescence duration was shortened by the cold temperatures in the valley. This effect was more distinct for late phases than for early phases since they experienced more inversion days. The higher the inversion frequency, the stronger the signal was. Acer pseudoplatanus proved to be more sensitive to cold temperatures compared to Fagus sylvatica. We conclude that cold-air pools have a considerable impact on the vegetation period of deciduous trees. Considering this effect, trees in the mid hillside slopes gain advantages compared to lower elevations. Our findings will help to improve knowledge about ecological drivers and responses in mountainous forest ecosystems. PMID:23912394

Schuster, Christina; Kirchner, Manfred; Jakobi, Gert; Menzel, Annette

2014-05-01

35

Sources and distribution of Campylobacter fetus subsp. jejuni in turkeys  

E-print Network

and enumeration of C. fetus subsp. jejune from turkey eggs and meat. Enrichment was in Brucella broth supplemented with ferrous sulfate, sodium metabisulfite, sodium pyru- vate, and five antimicrobial agents. Plating was on Brucella agar supplemented... ml of broth were as low as 0. 3 to 3. 3. Also, in this study, an effort was made to identify the source of C. fetus subsp. ~e uni in turkeys. C. fetus subsp. ~e uni was not isolated from fertile turkey eggs or from newly hatched poults...

Acuff, Gary Royce

2012-06-07

36

Comparisons of genetic and morphological distance with heterosis between Medicago sativa subsp. sativa and subsp. falcata  

Microsoft Academic Search

Biomass yield heterosis has been shown to exist between Medicago sativasubsp. sativa and Medica gosativa subsp. falcata. The objective of this study was to gain a better understanding of what morphological and genetic factors were most highly\\u000a correlated with total biomass yield heterosis. We calculated genetic distances among nine sativa and five falcate genotypes\\u000a based on amplified fragment length polymorphism

Heathcliffe Riday; E. Charles Brummer; T. Austin Campbell; Diane Luth; Patricia M. Cazcarro

2003-01-01

37

Growth of Fagus sylvatica saplings in an old-growth forest as affected by soil and light1 conditions2  

E-print Network

1 Growth of Fagus sylvatica saplings in an old-growth forest as affected by soil and light1 (Fontainebleau forest, biological reserve of La Tillaie, France),13 under varying humus and light conditions of the A horizon, typical of zones with poor18 mineralization of organic matter. Light conditions were more

Boyer, Edmond

38

Structure and dynamics of Japanese beech (Fagus japonica Maxim.) stools and sprouts in the regeneration of the natural forests  

Microsoft Academic Search

Structure and spatial distribution of stools and root-collar sprouts of Japanese beech (Fagus japonica) were studied to clarify the regeneration processes of the stool and the population, and the ecological importance of this stool formation in five quadrats of the natural forests with different forest floor vegetation on the Pacific side of Japan. F. japonica dominates in the canopy of

T. Ohkubo

1992-01-01

39

Adenine nucleotides and energy charge during dormancy breaking in embryo axes of Acer platanoides and Fagus sylvatica seeds  

Microsoft Academic Search

We analysed changes in AMP, ADP, and ATP concentrations and adenylate energy charge in Norway maple (Acer platanoides L.) and European beech (Fagus sylvatica L.) seeds during dormancy breaking (at 3 C) and in the control variant at 15 C. Values of the studied indicators in stratified\\u000a beech seeds were generally higher at 15 C, at least until germination (+3

Kazimierz Krawiarz; Zofia Szczotka

2005-01-01

40

Antioxidant potentials and rosmarinic acid levels of the methanolic extracts of Salvia verticillata (L.) subsp. verticillata and S. verticillata (L.) subsp. amasiaca (Freyn & Bornm.) Bornm  

Microsoft Academic Search

This study was designed to examine the in vitro antioxidant activities and rosmarinic acid levels of the methanol extracts of Salvia verticillata subsp. verticillata and S. verticillata subsp. amasiaca. The extracts were screened for their possible antioxidant activity by two complementary test systems, namely DPPH free radical-scavenging and ?-carotene\\/linoleic acid systems. In the first case, S. verticillata subsp. verticillata was

Bektas Tepe; Ozgur Eminagaoglu; H. Askin Akpulat; Enes Aydin

2007-01-01

41

Streptococcus dysgalactiae subsp. equisimilis bacteremia: an emerging infection.  

PubMed

The importance of group C and G Streptococcus dysgalactiae subspecies equisimilis (S. dysgalactiae subsp. equisimilis) as a significant pathogen has recently been better recognized. S. dysgalactiae subsp. equisimilis disease can range in severity from milder skin and soft-tissue conditions such as wound infection, erysipelas, and cellulitis, to life-threatening necrotizing fasciitis and streptococcal toxic shock syndrome, thus sharing the clinical picture with S. pyogenes. The most common clinical manifestation of bacteremia is cellulitis. An increase in the incidence of S. dysgalactiae subsp. equisimilis bacteremia has been recognized. Invasive forms of this infection are most commonly found in elderly patients with underlying comorbidities and skin breakdown. The case fatality in bacteremia has been reported to be 15-18%. In this review, the epidemiology, clinical characteristics, and emm types of S. dysgalactiae subsp. equisimilis bacteremia are summarized. PMID:24682845

Rantala, S

2014-08-01

42

Genome Sequence of Bacillus thuringiensis subsp. kurstaki Strain HD-1  

PubMed Central

We report here the complete genome sequence of Bacillus thuringiensis subsp. kurstaki strain HD-1, which serves as the primary U.S. reference standard for all commercial insecticidal formulations of B.thuringiensis manufactured around the world. PMID:25035322

Day, Michael; Ibrahim, Mohamed; Dyer, David

2014-01-01

43

Original article Natural black pine (Pinus nigra subsp salzmannii)  

E-print Network

Pinus nigra subsp salzmannii has its cen- tral core of distribution in the dolomite-lime- stone mountain granitic range, representing a special paleogeographic and phytogenetic interest (Regato et al, 1992

Paris-Sud XI, Université de

44

Zur cytotaxonomie von Veronica chamaedrys L. agg., II.: subsp. micans M. Fischer , subsp. nova, eine weitere diploide Sippe  

Microsoft Academic Search

Veronica chamaedrys L. subsp.micans M.Fischer\\u000a , unterscheidet sich vonV. chamaedrys L. subsp.chamaedrys hauptschlich durch die meist hellgrn gefrbten und im Leben oberseits stets schwach glnzenden Laubbltter, deren Blattrand durchschnittlich mehr (911) Zhne aufweist, durch die stets drsenlose Infloreszenzbehaarung, die kleineren Blten mit schmleren Sepalen und hellblau (nicht leuchtend-sattblau) gefrbten Corollen sowie durch die diploide Chromosomenzahl (2 n=16). Sie tritt in

Manfred Fischer

1973-01-01

45

Ophiostoma arduennense sp. nov. (Ophiostomatales, Ascomycota) from Fagus sylvatica in southern Belgium.  

PubMed

Ophiostoma arduennense sp. nov. is described from several cultures isolated from Fagus sylvatica in southern Belgium. The species is mainly characterized by globose perithecia with small button-like bases ornamented with brown hyphal hairs of variable length and, long cylindrical necks ending in ostiolate hyphae. It is homothallic with small reniform ascospores and no apparent anamorph. It is closely associated with the ambrosia beetles Xyloterus domesticus and X. signatus. Its phylogenetic relationships within Ophiostoma are discussed and the species is compared with other Ophiostoma species associated with European beech or other broad-leaved trees in Europe, especially species of the O. quercus-O. piceae complex. The species is responsible for a dark brown staining of the sapwood and its role in the decline of beech in Southern Belgium is also discussed. PMID:16828272

Carlier, Franois-Xavier; Decock, Cony; Jacobs, Karin; Maraite, Henri

2006-07-01

46

Nitrogen storage dynamics are affected by masting events in Fagus crenata.  

PubMed

It is generally assumed that the production of a large crop of seeds depletes stores of resources and that these take more than 1 year to replenish; this is accepted, theoretically, as the proximate mechanism of mast seeding (resource budget model). However, direct evidence of resource depletion in masting trees is very rare. Here, we trace seasonal and inter-annual variations in nitrogen (N) concentration and estimate the N storage pool of individuals after full masting of Fagus crenata in two stands. In 2005, a full masting year, the amount of N in fruit litter represented half of the N present in mature leaves in an old stand (age 190-260 years), and was about equivalent to the amount of N in mature leaves in a younger stand (age 83-84 years). Due to this additional burden, both tissue N concentration and individual N storage decreased in 2006; this was followed by significant replenishment in 2007, although a substantial N store remained even after full masting. These results indicate that internal storage may be important and that N may be the limiting factor for fruiting. In the 4 years following full masting, the old stand experienced two moderate masting events separated by 2 years, whilst trees in the younger stand did not fruit. This different fruiting behavior may be related to different "costs of reproduction" in the full masting year 2005, thus providing more evidence that N may limit fruiting. Compared to the non-fruiting stand, individuals in the fruiting stand exhibited an additional increase in N concentrations in roots early in the 2007 growing season, suggesting additional N uptake from the soil to supply resource demand. The enhanced uptake may alleviate the N storage depletion observed in the full masting year. This study suggests that masting affects N cycle dynamics in mature Fagus crenata and N may be one factor limiting fruiting. PMID:24221082

Han, Qingmin; Kabeya, Daisuke; Iio, Atsuhiro; Inagaki, Yoshiyuki; Kakubari, Yoshitaka

2014-03-01

47

Leaf litter decomposition in temperate deciduous forest stands with a decreasing fraction of beech (Fagus sylvatica).  

PubMed

We hypothesised that the decomposition rates of leaf litter will increase along a gradient of decreasing fraction of the European beech (Fagus sylvatica) and increasing tree species diversity in the generally beech-dominated Central European temperate deciduous forests due to an increase in litter quality. We studied the decomposition of leaf litter including its lignin fraction in monospecific (pure beech) stands and in stands with up to five tree genera (Acer spp., Carpinus betulus, Fagus sylvatica, Fraxinus excelsior, Tilia spp.) using a litterbag approach. Litter and lignin decomposition was more rapid in stand-representative litter from multispecific stands than in litter from pure beech stands. Except for beech litter, the decomposition rates of species-specific tree litter did not differ significantly among the stand types, but were most rapid in Fraxinus excelsior and slowest in beech in an interspecific comparison. Pairwise comparisons of the decomposition of beech litter with litter of the other tree species (except for Acer platanoides) revealed a "home field advantage" of up to 20% (more rapid litter decomposition in stands with a high fraction of its own species than in stands with a different tree species composition). Decomposition of stand-representative litter mixtures displayed additive characteristics, not significantly more rapid than predicted by the decomposition of litter from the individual tree species. Leaf litter decomposition rates were positively correlated with the initial N and Ca concentrations of the litter, and negatively with the initial C:N, C:P and lignin:N ratios. The results support our hypothesis that the overall decomposition rates are mainly influenced by the chemical composition of the individual litter species. Thus, the fraction of individual tree species in the species composition seems to be more important for the litter decomposition rates than tree species diversity itself. PMID:20596729

Jacob, Mascha; Viedenz, Karin; Polle, Andrea; Thomas, Frank M

2010-12-01

48

Leaf litter decomposition in temperate deciduous forest stands with a decreasing fraction of beech (Fagus sylvatica)  

PubMed Central

We hypothesised that the decomposition rates of leaf litter will increase along a gradient of decreasing fraction of the European beech (Fagus sylvatica) and increasing tree species diversity in the generally beech-dominated Central European temperate deciduous forests due to an increase in litter quality. We studied the decomposition of leaf litter including its lignin fraction in monospecific (pure beech) stands and in stands with up to five tree genera (Acer spp., Carpinus betulus, Fagus sylvatica, Fraxinus excelsior, Tilia spp.) using a litterbag approach. Litter and lignin decomposition was more rapid in stand-representative litter from multispecific stands than in litter from pure beech stands. Except for beech litter, the decomposition rates of species-specific tree litter did not differ significantly among the stand types, but were most rapid in Fraxinus excelsior and slowest in beech in an interspecific comparison. Pairwise comparisons of the decomposition of beech litter with litter of the other tree species (except for Acerplatanoides) revealed a home field advantage of up to 20% (more rapid litter decomposition in stands with a high fraction of its own species than in stands with a different tree species composition). Decomposition of stand-representative litter mixtures displayed additive characteristics, not significantly more rapid than predicted by the decomposition of litter from the individual tree species. Leaf litter decomposition rates were positively correlated with the initial N and Ca concentrations of the litter, and negatively with the initial C:N, C:P and lignin:N ratios. The results support our hypothesis that the overall decomposition rates are mainly influenced by the chemical composition of the individual litter species. Thus, the fraction of individual tree species in the species composition seems to be more important for the litter decomposition rates than tree species diversity itself. PMID:20596729

Jacob, Mascha; Viedenz, Karin; Polle, Andrea

2010-01-01

49

Complete Genome Sequence of Mycoplasma capricolum subsp. capripneumoniae Strain 9231-Abomsa.  

PubMed

Mycoplasma capricolum subsp. capripneumoniae is the etiological agent of contagious caprine pleuropneumonia. We report here the complete and annotated genome sequence of M.capricolum subsp. capripneumoniae strain 9231-Abomsa. PMID:25323727

Dupuy, Virginie; Thiaucourt, Franois

2014-01-01

50

Complete Genome Sequence of Mycoplasma capricolum subsp. capripneumoniae Strain 9231-Abomsa  

PubMed Central

Mycoplasma capricolum subsp. capripneumoniae is the etiological agent of contagious caprine pleuropneumonia. We report here the complete and annotated genome sequence of M.capricolum subsp. capripneumoniae strain 9231-Abomsa. PMID:25323727

Thiaucourt, Francois

2014-01-01

51

The influence of microclimate and tree age on the defense capacityof European beech ( Fagus sylvatica L.) against oxidative stress  

Microsoft Academic Search

Microclimate and tree age have been suggested to be factors influencing the defense capacity against oxidative stress. Therefore, 5-year-old Fagus sylvatica seedlings were grown on a scaffolding in the sun and shade crown of 55-year-old trees throughout one growing season. Independent of tree age sun leaves had a lower specific leaf area, lower pigment contents and a more capacitive antioxidative

Gerhard Wieser; Karin Hecke; Michael Tausz; Thorsten E. E. Grams; Rainer Matyssek

2003-01-01

52

Foliar responses to ozone of Fagus sylvatica L. seedlings grown in shaded and in full sunlight conditions  

Microsoft Academic Search

Ozone (O3) is well known to affect photosynthesis on tree seedlings under experimental conditions. In natural conditions, young trees grow under a competitive environment that may alter light availability. Such conditions were simulated in an open-top chamber (OTC) experiment carried out in Southern Switzerland (Lattecaldo). The experimental set-up consisted of Fagus sylvatica (beech) seedling plots (planted within the same chamber)

Chiara Cascio; Marcus Schaub; Kristopher Novak; Rosanna Desotgiu; Filippo Bussotti; Reto J. Strasser

2010-01-01

53

The physiological advantage of an ecological filter species, Indocalamus longiauritus , over co-occurring Fagus lucida and Castanopsis lamontii seedlings  

Microsoft Academic Search

Indocalamus longiauritus (a dwarf bamboo) dominates forest understory and functions as an ecological filter to hinder the regeneration of canopy tree\\u000a species in many temperate forests. However, the physiological mechanism underlying the function of ecological filters is not\\u000a clear. In this study, we measured leaf-level carbon capture ability and use efficiency of the dwarf bamboo and the co-existing\\u000a Fagus lucida

Kundong Bai; Debing Jiang; Kunfang Cao; Debao Liao; Xianchong Wan

2011-01-01

54

Photosynthetic induction in leaves of co-occurring Fagus lucida and Castanopsis lamontii saplings grown in contrasting light environments  

Microsoft Academic Search

Photosynthetic induction times and photoinhibition in relation to simulated sunflecks (sudden increase of irradiance from\\u000a 20 to 1,500?molm?2s?1) were examined in leaves of co-occurring Fagus lucida (a deciduous tree) and Castanopsis lamontii (an evergreen tree) saplings grown either in a beech forest understory or in an adjacent open site during a late rainy season.\\u000a Two hypotheses were tested: (1) understory

Kun-dong Bai; De-bao Liao; De-bing Jiang; Kun-fang Cao

2008-01-01

55

Dynamics of physicochemical properties and occurrence of fungal fruit bodies during decomposition of coarse woody debris of Fagus crenata  

Microsoft Academic Search

The pattern of changes in the physicochemical properties of wood, and its relationship with fungal succession during decomposition\\u000a of coarse woody debris (CWD) of beech (Fagus crenata Blume) were investigated. In total, 47 snags and 66 logs were assigned to a system of five decay classes, and were used for\\u000a analysis of the decomposition process. The decomposition process consists of

Yu Fukasawa; Takashi Osono; Hiroshi Takeda

2009-01-01

56

Nanoscale Similarities in the Substructure of the Exines of FagusPollen Grains and LycopodiumSpores  

Microsoft Academic Search

The exine substructure of an angiosperm,Fagus sylvatica(beech) pollen and a pteridophyte,Lycopodium clavatum(a club moss) spore was investigated by scanning tunnelling microscopy. These pollen and spores, despite their distinct differences in structure and morphology on a micrometre scale, have very similar substructure on a nanometre scale. The substructure appears to consist of a multi-helix, i.e. a helical chain in turn wound

JESPER WITTBORN; K. V RAO; G EL-GHAZALY; J. R ROWLEY

1998-01-01

57

Single PCR and nested PCR with a mimic molecule for detection of Mycobacterium avium subsp. paratuberculosis  

Microsoft Academic Search

Mycobacterium avium subsp. paratuberculosis is the causative agent of Johnes disease in ruminants. The current methods for detection of M. avium subsp. paratuberculosis are slow and insensitive. We report the use of a polymerase chain reaction (PCR) based on IS900 to confirm growth of M. avium subsp. paratuberculosis in primary bacterial cultures from bovine tissue and fecal samples. The use

Stina Englund; Andrs Ballagi-Pordny; Gran Blske; Karl-Erik Johansson

1999-01-01

58

Bartonella vinsonii subsp. berkhoffii in free-ranging white-tailed deer (Odocoileus virginianus).  

PubMed

Bartonella vinsonii subsp. berkhoffii has not been detected previously in white-tailed deer (Odocoileus virginianus). We tested whole blood from 60 white-tailed deer for Bartonella spp. DNA; three (5%) were positive for Bartonella vinsonii subsp. berkhoffii. This is the first detection of Bartonella vinsonii subsp. berkhoffii in white-tailed deer. PMID:23568932

Chitwood, M Colter; Maggi, Ricardo G; Kennedy-Stoskopf, Suzanne; Toliver, Marce; DePerno, Christopher S

2013-04-01

59

Isolation of Campylobacter fetus subsp. jejuni from migratory waterfowl.  

PubMed Central

Since the sources from which humans acquire Campylobacter enteritis are only partially known, we studied the frequency of carriage of Campylobacter fetus subsp. jejuni in migratory waterfowl. Cecal contents of various species of wild ducks were cultured on selective media that contained antibiotics to inhibit normal flora. Thirty-five percent of the 445 ducks cultured harbored C. fetus subsp. jejuni. Migratory waterfowl are yet another reservoir for this enteric pathogen and may be of public health importance for humans in the contamination of water or when used as food. PMID:7217334

Luechtefeld, N A; Blaser, M J; Reller, L B; Wang, W L

1980-01-01

60

Beech (Fagus sylvatica) response to ozone exposure assessed with a chlorophyll a fluorescence performance index.  

PubMed

This paper describes a relationship between ozone exposure, biomass, visual symptoms and a chlorophyll a fluorescence performance index for young beech trees (Fagus sylvatica). The plants were exposed to four levels of ozone in open-top fumigation chambers (50, 85, 100% of ambient, and 50% of ambient+30 nl l(-1) ozone) that fluctuated in parallel with ambient ozone during a single growing season. The trees were fumigated in the four treatments with ozone levels corresponding to an AOT40 (accumulated exposure above a threshold of 40 nl l(-1)) of 0.01, 3.35, 7.06 and 19.70 microl l(-1) h, respectively. Highly significant differences were found between the 50% of ambient+30 nl l(-1) ozone treatment and all other treatments, with a 70.5% reduction in primary photosynthetic performance, as measured with the PI index. The reduction of the PI values demonstrated a high correlation with visual symptom development (r(2)=0.98), and by the end of September with biomass loss (r(2)=0.99). A significant ozone exposure-response relationship was found between AOT40 and primary photochemistry (r(2)=0.97). Thus, analysis of PI provides an alternative method for regional monitoring of tree health within the context of the currently employed AOT40. PMID:15092883

Clark, A J; Landolt, W; Bucher, J B; Strasser, R J

2000-09-01

61

Ecological determinants of mating system within and between three Fagus sylvatica populations along an elevational gradient.  

PubMed

Studies addressing the variation of mating system between plant populations rarely account for the variability of these parameters between individuals within populations, although this variability is often non-negligible. Here, we propose a new direct method based on paternity analyses (Mixed Effect Mating Model) to estimate individual migration (mi ) and selfing rates (si ) together with the pollen dispersal kernel. Using this method and the KINDIST approach, we investigated the variation of mating system parameters within and between three populations of Fagus sylvatica along an elevational gradient. Among the mother trees, si varied from 0% to 48%, mi varied from 12% to 86% and the effective number of pollen donors (Nepi ) varied from 2 to 364. The mating patterns differed along the gradient, the top population showing higher m and lower s, and a trend to higher Nep than the bottom populations. The phenological lag shaped long-distance pollen flow both within population (by increasing mi at mother-tree level) and between populations (by increasing m at high elevation). Rather than the mate density, the canopy density was detected as a major mating system determinant within population; it acted as a barrier to pollen flow, decreasing the proportion of long-distance pollen flow and increasing si . Overall, the effects of ecological factors on mating system were not the same within vs. between populations across the gradient, and these factors also differed from those traditionally found to shape variation at range-wide scale, highlighting the interest of multiscale approaches. PMID:23952125

Gauzere, Julie; Klein, Etienne K; Oddou-Muratorio, Sylvie

2013-10-01

62

Variation in biogenic volatile organic compound emission pattern of Fagus sylvatica L. due to aphid infection  

NASA Astrophysics Data System (ADS)

Volatile organic compounds (VOCs) have been the focus of interest to understand atmospheric processes and their consequences in formation of ozone or aerosol particles; therefore, VOCs contribute to climate change. In this study, biogenic VOCs (BVOCs) emitted from Fagus sylvatica L. trees were measured in a dynamic enclosure system. In total 18 compounds were identified: 11 monoterpenes (MT), an oxygenated MT, a homoterpene (C 14H 18), 3 sesquiterpenes (SQT), isoprene and methyl salicylate. The frequency distribution of the compounds was tested to determine a relation with the presence of the aphid Phyllaphis fagi L. It was found that linalool, (E)-?-ocimene, ?-farnesene and a homoterpene identified as (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), were present in significantly more samples when infection was present on the trees. The observed emission spectrum from F. sylvatica L. shifted from MT to linalool, ?-farnesene, (E)-?-ocimene and DMNT due to the aphid infection. Sabinene was quantitatively the most prevalent compound in both, non-infected and infected samples. In the presence of aphids ?-farnesene and linalool became the second and third most important BVOC emitted. According to our investigation, the emission fingerprint is expected to be more complex than commonly presumed.

Jo, .; Van Langenhove, H.; impraga, M.; Steppe, K.; Amelynck, C.; Schoon, N.; Mller, J.-F.; Dewulf, J.

2010-01-01

63

Linear Plasmid in the Genome of Clavibacter michiganensis subsp. sepedonicus  

PubMed Central

Contour-clamped homogeneous electric field gel analysis of genomic DNA of the plant pathogen Clavibacter michiganensis subsp. sepedonicus revealed the presence of a previously unreported extrachromosomal element. This new element was demonstrated to be a linear plasmid. Of 11 strains evaluated, all contained either a 90-kb (pCSL1) or a 140-kb (pCSL2) linear plasmid. PMID:11976316

Brown, Susan E.; Knudson, Dennis L.; Ishimaru, Carol A.

2002-01-01

64

Novel cyanide-hydrolyzing enzyme from Alcaligenes xylosoxidans subsp. denitrificans  

SciTech Connect

A cyanide-metabolizing bacterium, strain DF3, isolated from soil was identified as Alcaligenes xylosoxidans subsp. denitrificans. Whole cells and cell extracts of strain DF3 catalyzed hydrolysis of cyanide to formate and ammonia (HCN + 2H{sub 2}O {r arrow} HCOOH + NH{sub 3}) without forming formamide as a free intermediate. The cyanide-hydrolyzing activity was inducibly produced in cells during growth in cyanide-containing media. Cyanate (OCN{sup {minus}}) and a wide range of aliphatic and aromatic nitriles were not hydrolyzed by intact cells of A. xylosoxidans subsp. denitrificans DF3. Strain DF3 hydrolyzed cyanide with great efficacy. Thus, by using resting induced cells at a concentration of 11.3 mg (dry weight) per ml, the cyanide concentration could be reduced from 0.97 M (approximately 25,220 ppm) to less than 77 nM (approximately 0.002 ppm) in 55 h. Enzyme purification established that cyanide hydrolysis by A. xylosoxidans subsp. denitrificans DF3 was due to a single intracellular enzyme. The molecular mass of the active enzyme (purity, {gt}97% as determined by amino acid sequencing) was estimated to be {gt}300,000 Da. The cyanide-hydrolyzing enzyme of A. xylosoxidans subsp. denitrificans DF3 was tentatively named cyanidase to distinguish it from known nitrilases (EC 3.5.5.1) which act on organic nitriles.

Ingvorsen, K.; Hojer-Pederson, B.; Godtfredsen, S.E. (Novo Nordisk A/S, Bagsvaerd (Denmark))

1991-06-01

65

Staphylococcus aureus subsp. anaerobius strain ST1464 genome sequence  

PubMed Central

Staphylococcus aureus subsp. anaerobius is responsible for Morel's disease in animals and a cause of abscess in humans. It is characterized by a microaerophilic growth, contrary to the other strains of S. aureus. The 2,604,446-bp genome (32.7% GC content) of S. anaerobius ST1464 comprises one chromosome and no plasmids. The chromosome contains 2,660 open reading frames (ORFs), 49 tRNAs and three complete rRNAs, forming one complete operon. The size of ORFs ranges between 100 to 4,600 bp except for two ORFs of 6,417 and 7,173 bp encoding segregation ATPase and non-ribosomal peptide synthase, respectively. The chromosome harbors Staphylococcus phage 2638A genome and incomplete Staphylococcus phage genome PT1028, but no detectable CRISPRS. The antibiotic resistance gene for tetracycline was found although Staphylococcus aureus subsp. anaerobius is susceptible to tetracycline in-vitro. Intact oxygen detoxification genes encode superoxide dismutase and cytochrome quinol oxidase whereas the catalase gene is impaired by a stop codon. Based on the genome, in-silico multilocus sequence typing indicates that S. aureus subsp. anaerobius emerged as a clone separated from all other S. aureus strains, illustrating host-adaptation linked to missing functions. Availability of S. aureus subsp. anaerobius genome could prompt the development of post-genomic tools for its rapid discrimination from S. aureus. PMID:24501641

Elbir, Haitham; Robert, Catherine; Nguyen, Ti Thien; Gimenez, Gregory; El Sanousi, Sulieman M.; Flock, Jan-Ingmar; Raoult, Didier

2013-01-01

66

Laminaria japonica Extract, an Inhibitor of Clavibater michiganense Subsp. Sepedonicum  

PubMed Central

Bacterial ring rot of potato is one of the most serious potato plant and tuber diseases. Laminaria japonica extract was investigated for its antimicrobial activity against Clavibater michiganense subsp. sepedonicum (Spieckermann & Kotthoff) Davis et al., the causative agent of bacterial ring rot of potato. The results showed that the optimum extraction conditions of antimicrobial substances from L. japonica were an extraction temperature of 80C, an extraction time of 12 h, and a solid to liquid ratio of 1?25. Active compounds of L. japonica were isolated by solvent partition, thin layer chromatography (TLC) and column chromatography. All nineteen fractionations had antimicrobial activities against C. michiganense subsp. sepedonicum, while Fractionation three (Fr.3) had the highest (P<0.05) antimicrobial activity. Chemical composition analysis identified a total of 26 components in Fr.3. The main constituents of Fr.3 were alkanes (80.97%), esters (5.24%), acids (4.87%) and alcohols (2.21%). Antimicrobial activity of Fr.3 against C. michiganense subsp. sepedonicum could be attributed to its ability to damage the cell wall and cell membrane, induce the production of reactive oxygen species (ROS), increase cytosolic Ca2+ concentration, inhibit the glycolytic pathway (EMP) and tricarboxylic acid (TCA) cycle, inhibit protein and nucleic acid synthesis, and disrupt the normal cycle of DNA replication. These findings indicate that L. japonica extracts have potential for inhibiting C. michiganense subsp. sepedonicum. PMID:24714388

Cai, Jin; Feng, Jia; Xie, Shulian; Wang, Feipeng; Xu, Qiufeng

2014-01-01

67

Identification of the Treponema pallidum subsp. pallidum glycerophosphodiester phosphodiesterase homologue  

Microsoft Academic Search

To identify potential opsonic targets of Treponema pallidum subsp. pallidum, a treponemal genomic expression library was constructed and differentially screened with opsonic and non-opsonic T. pallidum antisera. This method identified an immunoreactive clone containing an open reading frame encoding a 356 residue protein. Nucleotide sequence analysis demonstrated the translated protein to be a homologue of glycerophosphodiester phosphodiesterase, a glycerol metabolizing

Caroline E. Stebeck; Jeanne M. Shaffer; Thomas W. Arroll; Sheila A. Lukehart; Wesley C. Van Voorhis

1997-01-01

68

Lactococcus lactis subsp. tructae subsp. nov. isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss).  

PubMed

The species Lactococcus lactis currently includes three subspecies; L. lactis subsp. lactis and L. lactis subsp. cremoris, isolated from milk sources, and L. lactis subsp. hordniae, isolated from the leafhopper Hordnia circellata. In this study, three strains, designated L105(T), I3 and L101, were isolated from the intestinal mucus of brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss). These strains were closely related to members of the species Lactococcus lactis. Strain L105(T) showed 99.4 % 16S rRNA gene sequence similarity to that of the type strains L. lactis subsp. lactis NCDO 604(T) and L. lactis subsp. hordniae NCDO 2181(T) and showed 99.9 % similarity to the type strain Lactococcus lactis subsp. cremoris NCDO 607(T). Analysis of two housekeeping genes, rpoB and recA, confirmed the close relationship between the novel strains and L. lactis subsp. cremoris with similarities of 99.3 and 99.7 %, respectively. The three strains could, however, be differentiated from their closest relatives on the basis of several phenotypic characteristics, as was the case for L. lactis subsp. lactis and L. lactis subsp. hordniae, which were also closely related on the basis of 16S rRNA, rpoB and recA gene sequence similarities. The strains isolated in this study represent a new subspecies, for which the name Lactococcus lactis subsp. tructae subsp. nov. is proposed. The type strain is L105(T) (?= LMG 24662(T) ?= DSM 21502(T)). PMID:20833888

Prez, Tania; Balczar, Jos Luis; Peix, Alvaro; Valverde, Angel; Velzquez, Encarna; de Blas, Ignacio; Ruiz-Zarzuela, Imanol

2011-08-01

69

Staphylococcus schleiferi subsp. coagulans subsp. nov. Isolated from the External Auditory Meatus of Dogs with External Ear Otitis  

Microsoft Academic Search

A new subspecies, Staphylococcus schleiferi subsp. couguluns, was isolated from the external auditory meatus of dogs suffering from external ear otitis and is described on the basis of studies of 21 strains. Phenotypic studies showed that these strains are more closely related to Staphylococcus intermedius than to other staphylococci, but DNA hybridization studies indicated that they are closely related to

SHIZUNOBU IGIMI; EIJI TAKAHASHI; TOMOTARI MITSUOKA

70

Differences in transpiration characteristics of Japanese beech trees, Fagus crenata, in Japan.  

PubMed

Japanese beech (Fagus crenata Blume) is widely distributed across the Japan archipelago. This species requires morphological and physiological plasticity to cope with the diverse environmental conditions across its geographical range. In this study, we monitored transpiration (E) to examine plasticity mechanisms as an example of geographical variation in whole-tree water use. We determined E by measuring the sap flux of Japanese beech trees in three stands: Kuromatsunai (KR), Kawatabi (KW) and Shiiba (SH), which were located in different areas in Japan. We conducted biometric measurements to characterize leaf and crown morphology and evaluated geographical variations in E characteristics, such as canopy aerodynamic conductance, canopy stomatal conductance (G(S)) and decoupling coefficient (Omega). Leaf morphology and crown shape showed clear geographical clines. Individual leaf areas decreased in the order KR > KW > SH. The crown shape in the KR and KW stands was cylindrical but planar in the SH stand. We evaluated the effects of leaf and crown morphology on E characteristics. The Omega values showed that, while E in the KW and SH stands was highly sensitive to G(S) and atmospheric evaporative demand, E in the KR stand was sensitive to radiative energy. To maximize carbon gain without further water loss, trees maintain a high G(S) in a moist habitat. For example, the KR trees may decrease E by reducing their absorbed radiation energy by adjusting the individual leaf size and crown structure. Our results indicate that the geographical variation in the water use pattern of Japanese beech is determined by the interaction between its physiological and morphological status. PMID:20392878

Tateishi, Makiko; Kumagai, Tomo'omi; Suyama, Yoshihisa; Hiura, Tsutom

2010-06-01

71

Carbon isotope discrimination during branch photosynthesis of Fagus sylvatica: field measurements using laser spectrometry.  

PubMed

On-line measurements of photosynthetic carbon isotope discrimination ((13)?) under field conditions are sparse. Hence, experimental verification of the natural variability of instantaneous (13)? is scarce, although (13)? is, explicitly and implicitly, used from leaf to global scales for inferring photosynthetic characteristics. This work presents the first on-line field measurements of (13)? of Fagus sylvatica branches, at hourly resolution, using three open branch bags and a laser spectrometer for CO? isotopologue measurements (QCLAS-ISO). Data from two August/September field campaigns, in 2009 and 2010, in a temperate forest in Switzerland are shown. Diurnal variability of (13)? was substantial, with mean diurnal amplitudes of ~9 and maximum diurnal amplitudes of ~20. The highest (13)? were generally observed during early morning and late afternoon, and the lowest (13)? during midday. An assessment of propagated standard deviations of (13)? demonstrated that the observed diurnal variation of (13)? was not a measurement artefact. Day-to-day variations of (13)? were summarized with flux-weighted daily means of (13)?, which ranged from 15 to 23 in 2009 and from 18 to 29 in 2010, thus displaying a considerable range of 8-11. Generally, (13)? showed the expected negative relationship with intrinsic water use efficiency. Diurnal and day-to-day variability of (13)? was, however, always better predicted by that of net CO? assimilation, especially in 2010 when soil moisture was high and vapour pressure deficit was low. Stomatal control of leaf gas exchange, and consequently (13)?, could only be identified under drier conditions in 2009. PMID:24676031

Gentsch, Lydia; Sturm, Patrick; Hammerle, Albin; Siegwolf, Rolf; Wingate, Lisa; Oge, Jrme; Baur, Thomas; Plss, Peter; Barthel, Matti; Buchmann, Nina; Knohl, Alexander

2014-04-01

72

Francisella tularensis subsp. tularensis group A.I, United States.  

PubMed

We used whole-genome analysis and subsequent characterization of geographically diverse strains using new genetic signatures to identify distinct subgroups within Francisella tularensis subsp. tularensis group A.I: A.I.3, A.I.8, and A.I.12. These subgroups exhibit complex phylogeographic patterns within North America. The widest distribution was observed for A.I.12, which suggests an adaptive advantage. PMID:24755401

Birdsell, Dawn N; Johansson, Anders; hrman, Caroline; Kaufman, Emily; Molins, Claudia; Pearson, Talima; Gyuranecz, Mikls; Naumann, Amber; Vogler, Amy J; Myrtenns, Kerstin; Larsson, Pr; Forsman, Mats; Sjdin, Andreas; Gillece, John D; Schupp, James; Petersen, Jeannine M; Keim, Paul; Wagner, David M

2014-05-01

73

Chromones and flavanones from artemisia campestris subsp. maritima  

Microsoft Academic Search

From the acetone extract of Artemisia campestris subsp. maritima six flavanones, two chromones and the coumarin scopoletin were isolated. 5-Hydroxy-7-methoxychromone and 5,7-dimethoxychromone are new compounds, while the flavanone eriodictyol-7,3?-dimethyl ether is reported for the first time in this species. The structures were elucidated by 1D and 2D NMR techniques. The unequivocal assignments of carbon resonances, mainly made by using 1D

Joo M. J. Vasconcelos; Artur M. S. Silva; Jos A. S. Cavaleiro

1998-01-01

74

Isolation by genomic subtraction of DNA probes specific for Erwinia carotovora subsp. atroseptica.  

PubMed Central

Erwinia carotovora subsp. atroseptica is a pathogen of potatoes in Europe because of its ability to induce blackleg symptoms early in the growing season. However, E. carotovora subsp. carotovora is not able to produce such severe symptoms under the same conditions. On the basis of the technique described by Straus and Ausubel (Proc. Natl. Acad. Sci. USA 87:1889-1893, 1990), we isolated DNA sequences of E. carotovora subsp. atroseptica 86.20 that were absent from the genomic DNA of E. carotovora subsp. carotovora CH26. Six DNA fragments ranging from ca. 180 to 400 bp were isolated, cloned, and sequenced. Each fragment was further hybridized with 130 microorganisms including 87 E. carotovora strains. One probe was specific for typical E. carotovora subsp. atroseptica strains, two probes hybridized with all E. carotovora subsp. atroseptica strains and with a few E. carotovora subsp. carotovora strains, and two probes recognized only a subset of E. carotovora subsp. atroseptica strains. The last probe was absent from the genomic DNA of E. carotovora subsp. carotovora CH26 but was present in the genomes of many strains, including those of other species and genera. This probe is homologous to the putP gene of Escherichia coli, which encodes a proline carrier. Further use of the probes is discussed. Images PMID:8117082

Darrasse, A; Kotoujansky, A; Bertheau, Y

1994-01-01

75

Historical (1749-1899) vs. Present-Day Sugar Maple  

E-print Network

for black cherry (Prunus serotina), soft (red) maple (Acer rubrum), and elm (Ulmus americana). The records (Fagus grandifolia), and basswood (Tilia americana), respectively. There were also a few records

76

Criterion3: MAINTENANCE OF FOREST ECOSYSTEM  

E-print Network

beetle, Sirex wood wasp, and European spruce bark beetle. KeyFindingsforCriterion3 48 #12;49C H A P t e R (Fagus grandifolia), eastern noncommercial hardwoods, spruce (Picea spp.) and balsam fir, other eastern

77

Soil and site factors influencing purple-flowered rhododendron ( Rhododendron ponticum L.) and eastern beech forests ( Fagus orientalis Lipsky) in Turkey  

Microsoft Academic Search

Eastern beech (Fagus orientalis Lipsky) is the major timber species growing in the Black Sea Region (BSR) forests of Turkey. Purple-flowered rhododendron (Rhododendron ponticum L.) is native to the region and currently dominates the understory of almost the entire eastern beech forest, reducing tree regeneration and growth. An aging beech overstory with little or no regeneration is the current state

Derya E?en; Shepard M. Zedaker; Jeffrey L. Kirwan; Paul Mou

2004-01-01

78

Seasonal changes in apparent hydraulic conductance and their implications for water use of European beech ( Fagus sylvatica L.) and sessile oak [ Quercus petraea (Matt.) Liebl] in South Europe  

Microsoft Academic Search

The water status of Fagus sylvatica L. and Quercus petraea (Matt) Liebl. was analysed during a cycle of progressive natural drought in southern Europe. Predawn (?pd) and midday water potential were measured in transpiring (?leaf) and non-transpiring leaves (?xyl). Furthermore, photosynthesis (A), stomatal conductance to water vapour (gs) and sap flow (Fd) were recorded on the same dates. Apparent leaf

I. Aranda; L. Gil; J. A. Pardos

2005-01-01

79

Comparison of pectic enzymes produced by Erwinia chrysanthemi, Erwinia carotovora subsp. carotovora, and Erwinia carotovora subsp. atroseptica.  

PubMed Central

Erwinia spp. that cause soft-rot diseases in plants produce a variety of extracellular pectic enzymes. To assess the correlation between patterns of pectic enzyme production and taxonomic classification, we compared the enzymes from representative strains. Supernatants obtained from polygalacturonate-grown cultures of nine strains of Erwinia chrysanthemi, three strains of E. carotovora subsp. carotovora, and three strains of E. carotovora subsp. atroseptica were concentrated and subjected to ultrathin-layer polyacrylamide gel isoelectric focusing. Pectate lyase, polygalacturonase, and exo-poly-alpha-D-galacturonosidase activities were visualized by staining diagnostically buffered pectate-agarose overlays with ruthenium red after incubation of the overlays with the isoelectric focusing gels. The isoelectric focusing profiles of pectate lyase and polygalacturonase were nearly identical for strains of E. carotovora subsp. carotovora and E. carotovora subsp. atroseptica, showing three pectate lyase isozymes with isoelectric points higher than 8.7 and a polygalacturonase with pI of ca. 10.2. Isoelectric focusing profiles of the E. chrysanthemi pectic enzymes were substantially different. Although there was considerable intraspecific heterogeneity, all strains produced at least four isozymes of pectate lyase, which could be divided into three groups: basic (pI, ca. 9.0 to 10.0), slightly basic (pI, ca. 7.0 to 8.5), and acidic (pI, ca. 4.0 to 5.0). Several strains of E. chrysanthemi also produced a single form of exo-poly-alpha-D-galacturonosidase (pI, ca. 8.0).(ABSTRACT TRUNCATED AT 250 WORDS) Images PMID:3752996

Ried, J L; Collmer, A

1986-01-01

80

Changes in BVOC emission pattern from Fagus sylvatica L. measured by thermal desorber GC-MS  

NASA Astrophysics Data System (ADS)

Considerable attention has been focused on biogenic volatile organic compound (BVOC) emissions from forest ecosystems because of their contribution to tropospheric oxidation processes and secondary aerosol formation [1, 2]. It became apparent that biogenic emissions show much more variation than previously assumed. In this poster we focus on the change in BVOC emission patterns from a four year old Fagus sylvatica L. during a growth chamber experiment (PAR, temperature controlled) lasting from March to November 2008. A dynamic branch enclosure system was used in our experiments. Ozone and VOC were removed from air entering the cuvette, as ozone level was found to be a critical parameter for degradation of the compounds [3]. Samples were collected on Tenax TA-Carbotrap solid phase adsorbent tubes and analyzed by TD-GC-MS. Measurements started before budburst of the tree and finished at the end of autumn. Over the entire period 33 samples have been analyzed, while 16 compounds were detected, including 10 monoterpenes (MT), 2 oxygenated-MTs, 2 sesquiterpenes (SQT), isoprene and methyl salicylate. Sabinene showed the highest emission, in an agreement with previous studies [4, 5]. Quantifiable emission appeared 21 days after budburst, and reached the highest level at the beginning of summer. MT emissions showed a clear trend in following each other. As an illustration the trend of sabinene and limonene emission is presented. In the middle of autumn phytophaga infection was observed on the tree induced by Two-spotted mite (Tetranychus urticae). New compounds appeared as a result of infection (linalool, methyl salicylate, (E,E)-?-farnesene, unknown oxygenated-MT, unknown SQT) and became dominant over sabinene, explained by the low MT emissions at this time of the year. These observations point at the importance of further investigation of BVOC emissions (especially SQTs and oxygenated-MTs) and the need for a proper quantification system of these compounds. We would like to emphasize our acknowledgement to BELSPO (Belgian Science Policy; IMPECVOC contract # SD/TE/03A) and to FWO (Fonds voor Wetenschappelijk Onderzoek; contract # B/07659/02) for supporting the research program. [1] Ortega et al. (2008) Chemosphere (72) 365-380 [2] Duhl et al. (2008) Biogeosciences (5) 761-777 [3] Pollmann et al. (2005) Environ. Sci. Technol. (39) 9620-9629 [4] Moukhtar et al. (2005) Atmos. Environ. (39) 3535-3547 [5] Holzke et al. (2006) J. Atmos. Chem. (55) 81-102

Jo, .; van Langenhove, H.; Schietse, L.; Pokorska, O.; impraga, M.; Steppe, K.; Demarcke, M.; Amelynck, C.; Schoon, N.; Mller, J.-F.; Samson, R.; Dewulf, J.

2009-04-01

81

Mapping beech ( Fagus sylvatica L.) forest structure with airborne hyperspectral imagery  

NASA Astrophysics Data System (ADS)

Estimating forest structural attributes using multispectral remote sensing is challenging because of the saturation of multispectral indices at high canopy cover. The objective of this study was to assess the utility of hyperspectral data in estimating and mapping forest structural parameters including mean diameter-at-breast height (DBH), mean tree height and tree density of a closed canopy beech forest ( Fagus sylvatica L.). Airborne HyMap images and data on forest structural attributes were collected from the Majella National Park, Italy in July 2004. The predictive performances of vegetation indices (VI) derived from all possible two-band combinations (VI ( i, j) = ( Ri - Rj)/( Ri + Rj), where Ri and Rj = reflectance in any two bands) were evaluated using calibration ( n = 33) and test ( n = 20) data sets. The potential of partial least squares (PLS) regression, a multivariate technique involving several bands was also assessed. New VIs based on the contrast between reflectance in the red-edge shoulder (756-820 nm) and the water absorption feature centred at 1200 nm (1172-1320 nm) were found to show higher correlations with the forest structural parameters than standard VIs derived from NIR and visible reflectance (i.e. the normalised difference vegetation index, NDVI). PLS regression showed a slight improvement in estimating the beech forest structural attributes (prediction errors of 27.6%, 32.6% and 46.4% for mean DBH, height and tree density, respectively) compared to VIs using linear regression models (prediction errors of 27.8%, 35.8% and 48.3% for mean DBH, height and tree density, respectively). Mean DBH was the best predicted variable among the stand parameters (calibration R2 = 0.62 for an exponential model fit and standard error of prediction = 5.12 cm, i.e. 25% of the mean). The predicted map of mean DBH revealed high heterogeneity in the beech forest structure in the study area. The spatial variability of mean DBH occurs at less than 450 m. The DBH map could be useful to forest management in many ways, e.g. thinning of coppice to promote diameter growth, to assess the effects of management on forest structure or to detect changes in the forest structure caused by anthropogenic and natural factors.

Cho, Moses Azong; Skidmore, Andrew K.; Sobhan, Istiak

82

Leaf and stem CO/sub 2/ uptake in the three subfamilies of the Cactaceae. [Pereskia aculeata; Pereskia grandifolia; Maihuenia poeppigii; Carnegiea gigantea; Ferocactus acanthodes; Coryphantha vivipara; Mammillaria dioica; Opuntia ficus-inidica; Pereskiopsis porteri; Quiabentia chacoensis; Austrocylindropuntia subulata  

SciTech Connect

Net CO/sub 2/ uptake over 24-hour periods was examined for the leaves and for the stems of 11 species of cacti representing all three subfamilies. For Pereskia aculeata, Pereskia grandifolia, and Maihuenia poeppigii (subfamily Pereskioideae), all the net shoot CO/sub 2/ uptake was by the leaves and during the daytime. In contrast, for the leafless species Carnegiea gigantea, Ferocactus acanthodes, Coryphantha vivipara, and Mammillaria dioica (subfamily Cactoideae), all the shoot net CO/sub 2/ uptake was by the stems and at night. Similarly, for leafless Opuntia ficus-indica (subfamily Opuntioideae), all net CO/sub 2/ uptake occurred at night. For leafy members of the Opuntioideae (Pereskiopsis porteri, Quiabentia chacoensis, Austrocylindropuntia subulata), at least 88% of the shoot CO/sub 2/ uptake over 24 hours was by the leaves and some CO/sub 2/ uptake occurred at night. Leaves responded to the instantaneous level of photosynthetically active radiation (PAR) during the daytime, as occurs for C/sub 3/ plants, whereas nocturnal CO/sub 2/ uptake by stems of O. ficus-indica and F. acanthodes responded to the total daily PAR, as occurs for Crassulacean acid metabolism (CAM) plants. Thus, under the well-watered conditions employed, the Pereskioideae behaved as C/sub 3/ plants, the Cactoideae behaved as CAM plants, and the Opuntioideae exhibited characteristics of both pathways.

Nobel, P.S.; Hartsock, T.L.

1986-04-01

83

Refined, Circular Restriction Map of the Bacillus thuringiensis subsp. israelensis Plasmid Carrying the Mosquito Larvicidal Genes1  

E-print Network

Refined, Circular Restriction Map of the Bacillus thuringiensis subsp. israelensis Plasmid Carrying, 1999 All the genetic elements responsible for the mosquito larval toxicity of Bacillus thuringiensis Press The mosquito larvicidal activity of Bacillus thuringiensis subsp. israelensis is included

Zaritsky, Arieh

84

Molecular epidemiology of Mycobacterium avium subsp. paratuberculosis in a longitudinal study of three dairy herds.  

PubMed

The objective of this study was to evaluate whether cows that were low shedders of Mycobacterium avium subsp. paratuberculosis were passively shedding or truly infected with M. avium subsp. paratuberculosis. We also investigated whether it is possible that these M. avium subsp. paratuberculosis-infected animals could have been infected as adults by contemporary high-shedding animals (supershedders). The M. avium subsp. paratuberculosis isolates were obtained from a longitudinal study of three dairy herds in the northeastern United States. Isolates were selected from fecal samples and tissues at slaughter from all animals that were culture positive at the same time that supershedders were present in the herds. Shedding levels (CFU of M. avium subsp. paratuberculosis/g of feces) for the animals at each culture-positive occasion were determined. Using a multilocus short-sequence-repeat technique, we found 15 different strains of M. avium subsp. paratuberculosis from a total of 142 isolates analyzed. Results indicated herd-specific infection patterns; there was a clonal infection in herd C, with 89% of isolates from animals sharing the same strain, whereas herds A and B showed several different strains infecting the animals at the same time. Tissues from 80% of cows with at least one positive fecal culture (other than supershedders) were culture positive, indicating a true M. avium subsp. paratuberculosis infection. The results of M. avium subsp. paratuberculosis strain typing and observed shedding levels showed that at least 50% of low shedders have the same strain as that of a contemporary supershedder. Results of this study suggest that in a dairy herd, more of the low-shedding cows are truly infected with M. avium subsp. paratuberculosis than are passively shedding M. avium subsp. paratuberculosis. The sharing of strains between low shedders and the contemporary supershedders suggests that low shedders may have been infected by environmental exposure of M. avium subsp. paratuberculosis. PMID:21209171

Pradhan, Abani K; Mitchell, Rebecca M; Kramer, Aagje J; Zurakowski, Michael J; Fyock, Terry L; Whitlock, Robert H; Smith, Julia M; Hovingh, Ernest; Van Kessel, Jo Ann S; Karns, Jeffrey S; Schukken, Ynte H

2011-03-01

85

Molecular Epidemiology of Mycobacterium avium subsp. paratuberculosis in a Longitudinal Study of Three Dairy Herds?  

PubMed Central

The objective of this study was to evaluate whether cows that were low shedders of Mycobacterium avium subsp. paratuberculosis were passively shedding or truly infected with M. avium subsp. paratuberculosis. We also investigated whether it is possible that these M. avium subsp. paratuberculosis-infected animals could have been infected as adults by contemporary high-shedding animals (supershedders). The M. avium subsp. paratuberculosis isolates were obtained from a longitudinal study of three dairy herds in the northeastern United States. Isolates were selected from fecal samples and tissues at slaughter from all animals that were culture positive at the same time that supershedders were present in the herds. Shedding levels (CFU of M. avium subsp. paratuberculosis/g of feces) for the animals at each culture-positive occasion were determined. Using a multilocus short-sequence-repeat technique, we found 15 different strains of M. avium subsp. paratuberculosis from a total of 142 isolates analyzed. Results indicated herd-specific infection patterns; there was a clonal infection in herd C, with 89% of isolates from animals sharing the same strain, whereas herds A and B showed several different strains infecting the animals at the same time. Tissues from 80% of cows with at least one positive fecal culture (other than supershedders) were culture positive, indicating a true M. avium subsp. paratuberculosis infection. The results of M. avium subsp. paratuberculosis strain typing and observed shedding levels showed that at least 50% of low shedders have the same strain as that of a contemporary supershedder. Results of this study suggest that in a dairy herd, more of the low-shedding cows are truly infected with M. avium subsp. paratuberculosis than are passively shedding M. avium subsp. paratuberculosis. The sharing of strains between low shedders and the contemporary supershedders suggests that low shedders may have been infected by environmental exposure of M. avium subsp. paratuberculosis. PMID:21209171

Pradhan, Abani K.; Mitchell, Rebecca M.; Kramer, Aagje J.; Zurakowski, Michael J.; Fyock, Terry L.; Whitlock, Robert H.; Smith, Julia M.; Hovingh, Ernest; Van Kessel, Jo Ann S.; Karns, Jeffrey S.; Schukken, Ynte H.

2011-01-01

86

SHORTER NOTES Botrychium lanceolatum subsp. angustisegmentum in Ohio.--In the treat-  

E-print Network

SHORTER NOTES Botrychium lanceolatum subsp. angustisegmentum in Ohio.--In the treat- ment, Botrychium lanceolatum subsp. angustisegmentum, as encompassing an area extending from Ontario's Lake­2001 the Ohio Department of Natural Resources listed B. lanceolatum as extirpated because no Ohio collections

Barker, Michael S.

87

Complete Genome Sequence of Salmonella enterica subsp. enterica Serovar Enteritidis Strain SEJ  

PubMed Central

Salmonella enterica constitutes a group of enteric pathogens with a broad host range, including humans, reptiles, and birds. S.enterica subsp. enterica is a common cause of inflammatory diarrhea in humans. We present the draft genome of S.enterica subsp. enterica serovar Enteritidis strain SEJ, including a 59-kbp plasmid. PMID:25342692

Bishop-Lilly, K. A.; Frey, K. G.; Daligault, H. E.; Davenport, K. W.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Chertkov, O.; Freitas, T.; Jaissle, J.; Koroleva, G. I.; Ladner, J. T.; Minogue, T. D.; Palacios, G. F.; Redden, C. L.; Xu, Y.

2014-01-01

88

Development of Luminescent Mycobacterium avium subsp. paratuberculosis for Rapid Screening of Vaccine Candidates in Mice  

PubMed Central

Mycobacterium avium subsp. paratuberculosis is a slowly growing mycobacterial species, requiring 6 to 8 weeks of culture before colonies can be counted visually. Here, we describe the development of luminescent M. avium subsp. paratuberculosis expressing luxAB genes of Vibrio harveyi and its use for vaccine testing in an experimental mouse model, replacing fastidious CFU counting by rapid luminometry. PMID:16714604

Rosseels, Valerie; Roupie, Virginie; Zinniel, Denise; Barletta, Raul G.; Huygen, Kris

2006-01-01

89

Complete Genome Sequence of Salmonella enterica subsp. enterica Serovar Enteritidis Strain SEJ.  

PubMed

Salmonella enterica constitutes a group of enteric pathogens with a broad host range, including humans, reptiles, and birds. S.enterica subsp. enterica is a common cause of inflammatory diarrhea in humans. We present the draft genome of S.enterica subsp. enterica serovar Enteritidis strain SEJ, including a 59-kbp plasmid. PMID:25342692

Bishop-Lilly, K A; Frey, K G; Daligault, H E; Davenport, K W; Bruce, D C; Chain, P S; Coyne, S R; Chertkov, O; Freitas, T; Jaissle, J; Koroleva, G I; Ladner, J T; Minogue, T D; Palacios, G F; Redden, C L; Xu, Y; Johnson, S L

2014-01-01

90

SALMONELLA ENTERICA SUBSP. ENTERICA IN CATTLE EGRET (BUBULCUS IBIS) CHICKS FROM CENTRAL TEXAS: PREVALENCE,  

E-print Network

SALMONELLA ENTERICA SUBSP. ENTERICA IN CATTLE EGRET (BUBULCUS IBIS) CHICKS FROM CENTRAL TEXAS% to 95%. Seventeen Salmonella enterica subsp. enterica serotypes were isolated, of which the 4,5,12:i of Salmonella, but provided no evidence of transmission between these two species. Similar conclusions were

Mora, Miguel A.

91

Complete Genome Sequence of the Strong Mutator Salmonella enterica subsp. enterica Serotype Heidelberg Strain B182  

E-print Network

Complete Genome Sequence of the Strong Mutator Salmonella enterica subsp. enterica Serotype the first complete genome sequence of the Salmonella enterica subsp. enterica serotype Heidelberg B182 (cB182_4750; GC, 52.2%) and one circular plasmid of 37,581 bp (pB182_37; GC, 42.8%). Salmonella

Paris-Sud XI, Université de

92

Genetic diversity and phylogeography in two diploid ferns, Asplenium fontanum subsp. fontanum and A. petrarchae subsp. bivalens, in the western Mediterranean.  

PubMed

Asplenium fontanum subsp. fontanum and A. petrarchae subsp. bivalens are diploid rock ferns of limestone outcrops of the western Mediterranean region. Asplenium fontanum subsp. fontanum occurs from Valencia through northeastern Spain to the Alpes-Maritimes and Swiss Jura. Asplenium petrarchae subsp. bivalens occurs only on Majorca, in Valencia and possibly in southern Spain. We analysed allozyme and chloroplast genetic marker diversity in 75 populations of A. fontanum subsp. fontanum and 12 populations of A. petrarchae subsp. bivalens sampled from across their respective ranges. The two species show similar levels of species and population genetic diversity to one another and to other diploid European Asplenium taxa. Both are predominantly outbreeding, as indicated by F(IS) = 0.108 and 0.167 respectively. Substantial between-population differentiation results largely from differentiation between regions. Isolation by distance operates over limited geographic ranges, up to 50 km. In A. fontanum subsp. fontanum, the major geographical differentiation between Valencia and the rest of the taxon range probably represents an ancient range fragmentation. A less pronounced differentiation divides populations in the SW from those in the NE of the range, with evidence for a biogeographic link between the eastern Pyrenees and southeastern France. High diversity in the Pyrenees may either represent ancient population differentiation, or a suture zone. In A. petrarchae subsp. bivalens, populations on Majorca exhibit a subset of the genetic diversity present in Valencia, although the two regions are strongly differentiated by differing allele frequencies. Dispersal from the mainland may have founded Majorcan populations, although a role for in situ island survival cannot be excluded. PMID:19863721

Hunt, H V; Ansell, S W; Russell, S J; Schneider, H; Vogel, J C

2009-12-01

93

Nitrogen as a key regulator of flowering in Fagus crenata: understanding the physiological mechanism of masting by gene expression analysis.  

PubMed

The role of resource availability in determining the incidence of masting has been widely studied, but how floral transition and initiation are regulated by the resource level is unclear. We tested the hypothesis that floral transition is stimulated by high resource availabiltiy in Fagus crenata based on a new technique, the expression analyses of flowering genes. We isolated F. crenata orthologues of FLOWERING LOCUS T, LEAFY and APETALA1, and confirmed their functions using transgenic Arabidopsis thaliana. We monitored the gene expression levels for 5 years and detected a cycle of on and off years, which was correlated with fluctuations of the shoot-nitrogen concentration. Nitrogen fertilisation resulted in the significantly higher expression of flowering genes than the control, where all of the fertilised trees flowered, whereas the control did not. Our findings identified nitrogen as a key regulator of mast flowering, thereby providing new empirical evidence to support the resource budget model. PMID:25103959

Miyazaki, Yuko; Maruyama, Yosuke; Chiba, Yukako; Kobayashi, Masaki J; Joseph, Benesh; Shimizu, Kentaro K; Mochida, Keiichi; Hiura, Tsutom; Kon, Hirokazu; Satake, Akiko

2014-10-01

94

Bibenzyls and dihydroisocoumarins from white salsify ( Tragopogon porrifolius subsp. porrifolius)  

Microsoft Academic Search

A phytochemical investigation of three accessions of Tragopogon porrifolius L. subsp. porrifolius (Asteraceae, Lactuceae) yielded three new bibenzyl derivatives, 5,4?-dihydroxy-3-?-l-rhamnopyranosyl-(1?3)-?-d-xylopyranosyloxybibenzyl, 2-carboxyl-3,4?-dihydroxy-5-?-d-xylopyranosyloxybibenzyl, tragopogonic acid (2?carboxyl-3?,5?,4?-trihydroxyphenylethanone) and three dihydroisocoumarin derivatives, including the new natural product 6-O-methylscorzocreticoside I. One of the isolated bibenzyl derivatives is considered to be a precursor to the biosynthesis of dihydroisocoumarins. Structures of new compounds were established by HR

Christian Zidorn; Ulrike Lohwasser; Susanne Pschorr; Daniela Salvenmoser; Karl-Hans Ongania; Ernst P. Ellmerer; Andreas Brner; Hermann Stuppner

2005-01-01

95

Stilbenes and flavonoids from Artocarpus nitidus subsp. lingnanensis.  

PubMed

The first stilbene possessing a ?-aminobutyric acid lactam function, artocarpene (1), and a new flavanone, 2-hydroxynaringenin 4'-O-?-d-glucopyranoside (2), were isolated from the stems of Artocarpus nitidus subsp. lingnanensis along with four known compounds, 2-hydroxynaringenin (3), oxyresveratrol (4), 3,4',5-trihydroxy-3'-prenylstilbene (5) and norartocarpetin (6). Their structures were elucidated on the basis of spectroscopic data. Compounds 1 exhibited weak antioxidant activity and 2 displayed weak cytotoxicity against human lung cancer A549 cell line. PMID:21316425

Ti, Huihui; Wu, Ping; Lin, Lidong; Wei, Xiaoyi

2011-06-01

96

Vertical differences in autumn phenology of Fagus sylvatica L. in a mixed forest, southern Germany  

NASA Astrophysics Data System (ADS)

Phenological variation among trees of different heights provides a small scale ecological distinction within the forest allowing the optimization of light interception and consequently net carbon gain. Several studies showed that juveniles and suppressed adult individuals can adopt a "phenological escape" strategy by leafing out earlier during spring or by delaying autumn phenology in relation to adult overstory trees. While spring phenological variations in temperate forests were well studied, for autumn phenology it is still unclear whether ontogenetic or microclimatic factors are more decisive. We regularly observed leaf coloring and leaf fall phenology of 166 European beech individuals (Fagus sylvatica L.; Fagaceae), during autumn 2012 in a mixed forest (Kranzberger Forst) in southern Germany and installed 18 loggers for measuring air temperature and humidity at different sites and heights. Our objectives were: (1) to identify microclimatic differences at our observation sites (2) to determine the extent of phenological variations between trees of different life stages (overstory, mesostory and understory); and (3) to examine whether phenology varies between three different height canopy levels. We found that temperature data did not differ between height levels, but relative humidity was significantly higher in the lowest parts. In addition, overstory individuals were the first to start autumn phases followed by mesostory and understory trees. Leaf colouring and fall for understory trees appeared 31 and 23 days later compared to overstory trees. The transition of autumn phases (from the beginning of leaf colouring until the end of leaf fall) was most and significantly extended for overstory trees (mean of 62 days), followed by mesostory (46 days) and understory (38 days). Understory individuals started leaf colouring even 4 days after the onset of overstory leaf fall evidencing phenological avoidance between life stages. Besides this analysis of life stages we also found that upper canopy parts of individual trees were characterized by the earliest appearance of autumn phases; mean difference in onset of leaf colouring and fall between upper and lower levels was in each case -11 days. Mean peak dates did not differ between the highest canopy levels. Thus, transition of autumn phases was fastest for the lowest canopy level (mean of 19 days) than for the highest levels (35 days). Our results suggest that the observed differences were probably not related to temperature but to microclimatic variations in relative humidity and light availability. Furthermore, autumn phases of lower individuals (mesostory and understory) and lower canopy height parts were associated with a shortened transition of autumn phenological phases, probably also associated with fewer branches and leaves that might facilitate the synchronization of phenology. Since phenological development can considerably differ, generalizations are limited when considering trees of different life stages within a forest. Further studies should focus on autumn light conditions to investigate its influence on phenology and the possible gain of light acquisition during phenological avoidance.

Gressler, Eliana; Jochner, Susanne; Capdevielle-Vargas, Rene; Morellato, Patrcia; Menzel, Annette

2014-05-01

97

Unraveling the growth determinism of Fagus sylvatica: a hybrid data-model approach  

NASA Astrophysics Data System (ADS)

The physiological processes underlying the limitation of forest growth are still under debate. Growth has long been considered as a carbone (C) limited process (Sala et al., 2012). As a matter of facts, a recent global meta-analysis has shown good agreements between assimilated C and forest productivity (Litton et al., 2007). Consequently, a majority of the process-based productivity models considers growth as a fraction of the net primary production (NPP) (Lacointe et al., 2000; Sitch et al., 2003. However, investigations at the stand scale report conflicting results (Rocha et al., 2006, Mund et al., 2010) and are not systematically consistent with a strict C limitation of growth, thus challenging the C-centric paradigm. The mechanisms that potentially degrade the link between NPP and growth include: i) the direct effect of environmental factors on growth (Zweifel et al., 2006, Krner et al., 2003), ii) the temporal variability of the growth allocation coefficient, due either to ontogeny (Genet et al., 2009), or to the initial physiological state of the tree i.e. to the reaction to past conditions. Indeed, many dendrochronological and ecological studies have shown a correlation between growth and climatic factors of the previous years (e.g. Lebourgeois et al., 2005; Richardson et al., 2012). In this work, we used a hybrid data model approach in order to assess the determinant of Fagus sylvatica stem growth along a spatial gradient across France. Despite they could brought essential insight on tree functioning, intra-specific studies across contrasted sites are still lacking in the current debate. Standardized annual growth data series at the stand scale were calculated using circumference inventories and dendrochronological series on 17 plots of the RENECOFOR network. We used the process-based model CASTANEA, thoroughly validated in long term flux simulation across Europe (e.g. Delpierre et al. 2009), to simulate the annual NPP of the corresponding periods. We then investigated the dependency of annual growth on NPP, age and variables describing direct or indirect climatic conditions of the current (n) and the previous (n-1) year (e.g. simulated soil water content, sum of winter negative temperature, simulated growth phenology). Analyses were conducted as follows: first we used a Random Forest learning machine (RF) to select important variables and to obtain information on the form of the dependencies. We then formalized this information within the linear model framework to quantify the variability attributable to each factors and to conduct valid statistical tests. RF analysis revealed that NPP was the most important variable explaining growth, with a quasi-linear partial effect. The 2 other selected variables quantified the hydric stress of year (n) and (n-1), and impacted growth with high threshold effects. Analysis of covariance then revealed that both hydric variables significantly affect the NPP-growth relationship. The retained variables explained 29% of the growth variability. Growth of F. sylvatica is under complex control, involving C assimilation, direct effect of water shortage and lagged response to past condition. We used these results to implement in the CASTANEA model a new conceptual allocation scheme, validated at regional scale.

Guillemot, Joanns; Martin-StPaul, Nicolas; Delpierre, Nicolas; Franois, Christophe; Soudani, Kamel; Restoux, Gwendal; Dufrne, Eric

2013-04-01

98

Characterization of transposon insertion out- mutants of Erwinia carotovora subsp. carotovora defective in enzyme export and of a DNA segment that complements out mutations in E. carotovora subsp. carotovora, E. carotovora subsp. atroseptica, and Erwinia chrysanthemi.  

PubMed Central

Soft-rotting Erwinia spp. export degradative enzymes to the cell exterior (Out+), a process contributing to their ability to macerate plant tissues. Transposon (Tn5, Tn10, Tn10-lacZ) insertion Out- mutants were obtained in Erwinia carotovora subsp. carotovora 71 by using plasmid and bacteriophage lambda delivery systems. In these mutants, pectate lyases, polygalacturonase, and cellulase, which are normally excreted into the growth medium, accumulated in the periplasm. However, localization of the extracellular protease was not affected. The Out- mutants were impaired in their ability to macerate potato tuber tissue. Out+ clones were identified in a cosmid library of E. carotovora subsp. carotovora 71 by their ability to complement mutants. Localization of cyclic phosphodiesterase in the periplasm indicated that the Out+ plasmids did not cause lysis or a nonspecific protein release. The Out+ derivatives of the E. carotovora subsp. carotovora 71 mutants regained the ability to macerate potato tuber tissue. Our data indicate that a cluster of several genes is required for the Out+ phenotype. While one plasmid, pAKC260, restored the Out+ phenotype in each of the 31 mutants of E. carotovora subsp. carotovora, E. carotovora subsp. atroseptica, and Erwinia chrysanthemi, it failed to render Escherichia coli export proficient. Homologs of E. carotovora subsp. carotovora 71 out DNA were detected by Southern hybridizations in subspecies of E. carotovora under high-stringency conditions. In contrast, E. chrysanthemi sequences bearing homology to the E. carotovora subsp. carotovora 71 out DNA were detectable only under low-stringency hybridization. Thus, although the out genes are functional in these two soft-rotting bacterial groups, the genes appear to have diverged. Images PMID:2160934

Murata, H; Fons, M; Chatterjee, A; Collmer, A; Chatterjee, A K

1990-01-01

99

Biological activity of harpin produced by Pantoea stewartii subsp. stewartii.  

PubMed

Pantoea stewartii subsp. stewartii causes Stewart's wilt of sweet corn. A hypersensitive response and pathogenicity (Hrp) secretion system is needed to produce water-soaking and wilting symptoms in corn and to cause a hypersensitive response (HR) in tobacco. Sequencing of the hrp cluster revealed a putative harpin gene, hrpN. The product of this gene was overexpressed in Escherichia coli and shown to elicit the HR in tobacco and systemic resistance in radishes. The protein was designated HrpN(Pnss). Like other harpins, it was heat stable and protease sensitive, although it was three- to fourfold less active biologically than Erwinia amylovora harpin. We used antibodies to purified HrpN(Pnss) to verify that hrpN mutants could not produce harpin. This protein was secreted into the culture supernatant and was produced by strains of P. stewartii subsp. indologenes. In order to determine the importance of HrpN(Pnss) in pathogenesis on sweet corn, three hrpN::Tn5 mutants were compared with the wild-type strain with 50% effective dose, disease severity, response time, and growth rate in planta as parameters. In all tests, HrpN(Pnss) was not required for infection, growth, or virulence in corn or endophytic growth in related grasses. PMID:11605962

Ahmad, M; Majerczak, D R; Pike, S; Hoyos, M E; Novacky, A; Coplin, D L

2001-10-01

100

Intestinal colonization of neonatal animals by Campylobacter fetus subsp. jejuni.  

PubMed Central

Neonatal mice (2.3 to 2.8 g) were inoculated intragastrically with different human isolates of Campylobacter fetus subsp. jejuni. At weekly intervals thereafter, mice were sacrificed and dilution plate counts were performed on segments of the gastrointestinal tract. Mice were uniformly colonized by some strains for 2 weeks, whereas other strains were being cleared at that time. One strain (BO216) persisted in some mice for 3 weeks. The greatest number of organisms (10(7)) was recovered from the cecum and large intestine. The small intestine had from 10(2) to 10(5) colony-forming units. Colonization of the stomach was not found consistently. One strain killed 13% of the infected mice. Deaths occurred between 1 and 5 days postinfection. Two other strains killed a smaller percentage of challenged animals, and two additional strains killed none. Retarded weight gain was noticed in some, but not all, of the infected mice. The intestines of neonatal rats and rabbits were colonized much the same as those of mice, whereas hamsters were resistant to colonization. Preweanling mice, up to about 6.5 to 7.0 g, could be colonized with C. fetus subsp. jejuni after intragastric challenge, but weanling mice of larger weight (9.8 g) and young adult mice (18.3 g) could not. Scanning electron photomicrographs of the lower ileum showed campylobacters in and below the dried mucous gel that lines the intestines. The use of this model for additional studies is discussed. Images PMID:7287188

Field, L H; Underwood, J L; Pope, L M; Berry, L J

1981-01-01

101

Glycosylation of DsbA in Francisella tularensis subsp. tularensis?  

PubMed Central

In Francisella tularensis subsp. tularensis, DsbA has been shown to be an essential virulence factor and has been observed to migrate to multiple protein spots on two-dimensional electrophoresis gels. In this work, we show that the protein is modified with a 1,156-Da glycan moiety in O-linkage. The results of mass spectrometry studies suggest that the glycan is a hexasaccharide, comprised of N-acetylhexosamines, hexoses, and an unknown monosaccharide. Disruption of two genes within the FTT0789-FTT0800 putative polysaccharide locus, including a galE homologue (FTT0791) and a putative glycosyltransferase (FTT0798), resulted in loss of glycan modification of DsbA. The F. tularensis subsp. tularensis ?FTT0798 and ?FTT0791::Cm mutants remained virulent in the murine model of subcutaneous tularemia. This indicates that glycosylation of DsbA does not play a major role in virulence under these conditions. This is the first report of the detailed characterization of the DsbA glycan and putative role of the FTT0789-FTT0800 gene cluster in glycan biosynthesis. PMID:21803994

Thomas, Rebecca M.; Twine, Susan M.; Fulton, Kelly M.; Tessier, Luc; Kilmury, Sara L. N.; Ding, Wen; Harmer, Nicholas; Michell, Stephen L.; Oyston, Petra C. F.; Titball, Richard W.; Prior, Joann L.

2011-01-01

102

Stability evaluation of freeze-dried Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. bulgaricus in oral capsules  

PubMed Central

Freeze-drying is a common preservation technology in the pharmaceutical industry. Various studies have investigated the effect of different cryoprotectants on probiotics during freeze-drying. However, information on the effect of cryoprotectants on the stability of some Lactobacillus strains during freeze-drying seems scarce. Therefore, the aim of the present study was to establish production methods for preparation of oral capsule probiotics containing Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. Bulgaricus. It was also of interest to examine the effect of various formulations of cryoprotectant media containing skim milk, trehalose and sodium ascorbate on the survival rate of probiotic bacteria during freeze-drying at various storage temperatures. Without any cryoprotectant, few numbers of microorganisms survived. However, microorganisms tested maintained higher viability after freeze-drying in media containing at least one of the cryoprotectants. Use of skim milk in water resulted in an increased viability after lyophilization. Media with a combination of trehalose and skim milk maintained a higher percentage of live microorganisms, up to 82%. In general, bacteria retained a higher number of viable cells in capsules containing freeze-dried bacteria with sodium ascorbate after three months of storage. After this period, a marked decline was observed in all samples stored at 23C compared to those stored at 4C. The maximum survival rate (about 72-76%) was observed with media containing 6% skim milk, 8% trehalose and 4% sodium ascorbate. PMID:23181077

Jalali, M.; Abedi, D.; Varshosaz, J.; Najjarzadeh, M.; Mirlohi, M.; Tavakoli, N.

2012-01-01

103

Stability evaluation of freeze-dried Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. bulgaricus in oral capsules.  

PubMed

Freeze-drying is a common preservation technology in the pharmaceutical industry. Various studies have investigated the effect of different cryoprotectants on probiotics during freeze-drying. However, information on the effect of cryoprotectants on the stability of some Lactobacillus strains during freeze-drying seems scarce. Therefore, the aim of the present study was to establish production methods for preparation of oral capsule probiotics containing Lactobacillus paracasei subsp. tolerance and Lactobacillus delbrueckii subsp. Bulgaricus. It was also of interest to examine the effect of various formulations of cryoprotectant media containing skim milk, trehalose and sodium ascorbate on the survival rate of probiotic bacteria during freeze-drying at various storage temperatures. Without any cryoprotectant, few numbers of microorganisms survived. However, microorganisms tested maintained higher viability after freeze-drying in media containing at least one of the cryoprotectants. Use of skim milk in water resulted in an increased viability after lyophilization. Media with a combination of trehalose and skim milk maintained a higher percentage of live microorganisms, up to 82%. In general, bacteria retained a higher number of viable cells in capsules containing freeze-dried bacteria with sodium ascorbate after three months of storage. After this period, a marked decline was observed in all samples stored at 23C compared to those stored at 4C. The maximum survival rate (about 72-76%) was observed with media containing 6% skim milk, 8% trehalose and 4% sodium ascorbate. PMID:23181077

Jalali, M; Abedi, D; Varshosaz, J; Najjarzadeh, M; Mirlohi, M; Tavakoli, N

2012-01-01

104

A comparative study of Mycobacterium avium subsp. avium and Mycobacterium avium subsp. hominissuis in experimentally infected pigs  

PubMed Central

Background Mycobacterium avium subsp. avium (Maa) and Mycobacterium avium subsp. hominissuis (Mah) are opportunistic pathogens that may infect several species, including humans and pigs. Mah is however more frequently isolated from pigs than Maa, and it is unclear if this is due to difference in virulence or in exposure to the two organisms. Clinical isolates of each subspecies were administered perorally to ten domestic pigs, respectively. The animals were sacrificed at six and 12 weeks after inoculation. At necropsy, macroscopic lesions were recorded, and tissue samples were collected for mycobacterial culture, IS1245 real time PCR and histopathological examination. Culturing was also performed on faecal samples collected at necropsy. Results Macroscopic and histopathological lesions were detected in pigs infected with each subspecies, and bacterial growth and histopathological changes were demonstrated, also in samples from organs without gross pathological lesions. Six weeks after inoculation, live Mah was detected in faeces, as opposed to Maa. The presence of live mycobacteria was also more pronounced in Mah infected tonsils. In comparison, the Maa isolate appeared to have a higher ability of intracellular replication in porcine macrophages compared to the Mah isolate. Conclusions The study shows that both subspecies were able to infect pigs. Additionally, the more extensive shedding of Mah might cause pig-to-pig transmission and contribute to the higher incidence of infection caused by this subspecies. PMID:22284630

2012-01-01

105

Effects of Roundup() and glyphosate on three food microorganisms: Geotrichum candidum, Lactococcus lactis subsp. cremoris and Lactobacillus delbrueckii subsp. bulgaricus.  

PubMed

Use of many pesticide products poses the problem of their effects on environment and health. Amongst them, the effects of glyphosate with its adjuvants and its by-products are regularly discussed. The aim of the present study was to shed light on the real impact on biodiversity and ecosystems of Roundup(), a major herbicide used worldwide, and the glyphosate it contains, by the study of their effects on growth and viability of microbial models, namely, on three food microorganisms (Geotrichum candidum, Lactococcus lactis subsp. cremoris and Lactobacillus delbrueckii subsp. bulgaricus) widely used as starters in traditional and industrial dairy technologies. The presented results evidence that Roundup() has an inhibitory effect on microbial growth and a microbicide effect at lower concentrations than those recommended in agriculture. Interestingly, glyphosate at these levels has no significant effect on the three studied microorganisms. Our work is consistent with previous studies which demonstrated that the toxic effect of glyphosate was amplified by its formulation adjuvants on different human cells and other eukaryotic models. Moreover, these results should be considered in the understanding of the loss of microbiodiversity and microbial concentration observed in raw milk for many years. PMID:22362186

Clair, Emilie; Linn, Laura; Travert, Carine; Amiel, Caroline; Sralini, Gilles-Eric; Panoff, Jean-Michel

2012-05-01

106

The soil food web of two beech forests ( Fagus sylvatica ) of contrasting humus type: stable isotope analysis of a macro- and a mesofauna-dominated community  

Microsoft Academic Search

The structure of the soil food web in two beech (Fagus sylvatica) forests, the Gttinger Wald and the Solling forest (Northern Germany), was investigated using variations in tissue 15N concentrations of animal species or taxa. The Gttinger Wald is located on a limestone plateau and characterized by mull\\u000a humus with high macrofauna activity, particularly of Lumbricidae, Diplopoda and Isopoda. In

Stefan Scheu; Marin Falca

2000-01-01

107

Gnawing damage by rodents to the seedlings of Fagus crenata and Quercus mongolica var. grosseserrata in a temperate Sasa grassland-deciduous forest series in southwestern Japan  

Microsoft Academic Search

The effects of dwarf bamboo,Sasa, cover on the initial morrality of hardwood seedlings were investigated by transplanting 1-year-old beech (Fagus crenata) and current-year oak (Quercus mongolica var.grosseserrata) seedling to three different stands; old-growth beech and secondary oak forests withSasa undergrowth, and aSasa grassland in a grassland-forest series near the top of Mt Jippo, southwestern Japan. The most frequent cause of

Hideyuki Ida; Nobukazu Nakagoshi

1996-01-01

108

Ozone effects on visible foliar injury and growth of Fagus sylvatica and Viburnum lantana seedlings grown in monoculture or in mixture  

Microsoft Academic Search

Seedlings of Fagus sylvatica (beech) and Viburnum lantana (Viburnum) grown in monoculture and mixture were exposed to ambient and sub-ambient (charcoal-filtered) ozone concentrations in open-top chambers over the course of the 2003 and 2004 growing seasons at the WSL Lattecaldo open-top chamber facility in southern Switzerland. The aim of the study was to determine how the sensitivity to ozone in

Kristopher Novak; Marcus Schaub; Jrg Fuhrer; John M. Skelly; Beat Frey; Norbert Kruchi

2008-01-01

109

Down-regulation of defense genes and resource allocation into infected roots as factors for compatibility between Fagus sylvatica and Phytophthora citricola  

Microsoft Academic Search

Phytophthora citricola is a wide spread and highly aggressive pathogen of Fagus sylvatica. The hemibiotrophic oomycete infects the roots and establishes a compatible interaction with F. sylvatica. To investigate the transcriptional changes associated with P. citricola infection, 68 custom oligo-microarray measurements were conducted. Hierarchical as well as non-hierarchical clustering was\\u000a carried out to analyze the expression profiles. Experimental setup includes

Katja Schlink

2010-01-01

110

Response to canopy opening does not act as a filter to Fagus sylvatica and Acer sp. advance regeneration in a mixed temperate forest  

Microsoft Academic Search

\\u000a \\u000a In mixed-species forest stands, large losses in tree species diversity often occur during the regeneration phase. In a former\\u000a coppice-with-standards, we investigated whether the limiting stage in the recruitment process of advance regeneration is the\\u000a immediate seedling response to canopy release. Experimental canopy gaps were opened and the survival and growth of advance\\u000a seedlings (Fagus sylvatica, Acer pseudoplatanus,

Blandine Caquet; Pierre Montpied; Erwin Dreyer; Daniel Epron; Catherine Collet

2010-01-01

111

Seroprevalence of Bartonella vinsonii subsp. berkhoffii in urban and rural dogs in Turkey.  

PubMed

The seroprevalence of Bartonella vinsonii subsp. berkhoffii was investigated in stray urban dogs and shepherd and farm guard dogs from rural areas sampled from 10 provinces of Turkey. Sera from 855 dogs were examined for the presence of anti-B. vinsonii subsp. berkhoffii antibodies by indirect fluorescent antibody test. Overall, 56 (6.6%) of the 855 dogs examined, including 16 (3%) of the 522 stray dogs and 40 (12%) of the 333 rural dogs, were seropositive. This is the first report on prevalence of antibodies to B. vinsonii subsp. berkhoffii in dogs in Turkey. PMID:20574140

Celebi, Bekir; Taylan Ozkan, Aysegul; Kilic, Selcuk; Akca, Atilla; Koenhemsi, Lora; Pasa, Serdar; Yildiz, Kader; Mamak, Nuri; Guzel, Murat

2010-11-01

112

Integrative Cloning, Expression, and Stability of the cryIA(c) Gene from Bacillus thuringiensis subsp. kurstaki in a Recombinant Strain of Clavibacter xyli subsp. cynodontis  

PubMed Central

A bacterial endophyte was engineered for insecticidal activity against the European corn borer. The cryIA(c) gene from Bacillus thuringiensis subsp. kurstaki was introduced into the chromosome of Clavibacter xyli subsp. cynodontis by using an integrative plasmid vector. The integration vectors pCG740 and pCG741 included the replicon pGEM5Zf(+), which is maintained in Escherichia coli but not in C. xyli subsp. cynodontis; tetM as a marker for selection in C. xyli subsp. cynodontis; and a chromosomal fragment of C. xyli subsp. cynodontis to allow for homologous recombination between the vector and the bacterial chromosome. Insertion of vector DNA into the chromosome was demonstrated by DNA hybridization. Recombinant strains MDR1.583 and MDR1.586 containing the cryIA(c) gene were shown to produce the 133,000-kDa protoxin and several smaller immunoreactive proteins. Both strains were equally toxic to insect larvae in bioassays. Significant insecticidal activity was demonstrated in planta. The cryIA(c) gene and the tetM gene introduced into strain MDR1.586 were shown to be deleted from some cells, thereby giving rise to a noninsecticidal segregant population. In DNA hybridization experiments and insect bioassays, these segregants were indistinguishable from the wild-type strain. Overall, these results demonstrate the plausibility of genetically engineered bacterial endophytes for insect control. Images PMID:16349179

Lampel, Jay S.; Canter, Gayle L.; Dimock, Michael B.; Kelly, Jeffrey L.; Anderson, James J.; Uratani, Brenda B.; Foulke, James S.; Turner, John T.

1994-01-01

113

Comparative Genomic Hybridizations Reveal Genetic Regions within the Mycobacterium avium Complex That Are Divergent from Mycobacterium avium subsp. paratuberculosis Isolates  

PubMed Central

Mycobacterium avium subsp. paratuberculosis is genetically similar to other members of the Mycobacterium avium complex (MAC), some of which are nonpathogenic and widespread in the environment. We have utilized an M. avium subsp. paratuberculosis whole-genome microarray representing over 95% of the predicted coding sequences to examine the genetic conservation among 10 M. avium subsp. paratuberculosis isolates, two isolates each of Mycobacterium avium subsp. silvaticum and Mycobacterium avium subsp. avium, and a single isolate each of both Mycobacterium intracellulare and Mycobacterium smegmatis. Genomic DNA from each isolate was competitively hybridized with DNA from M. avium subsp. paratuberculosis K10, and open reading frames (ORFs) were classified as present, divergent, or intermediate. None of the M. avium subsp. paratuberculosis isolates had ORFs classified as divergent. The two M. avium subsp. avium isolates had 210 and 135 divergent ORFs, while the two M. avium subsp. silvaticum isolates examined had 77 and 103 divergent ORFs. Similarly, 130 divergent ORFs were identified in M. intracellulare. A set of 97 ORFs were classified as divergent or intermediate in all of the nonparatuberculosis MAC isolates tested. Many of these ORFs are clustered together on the genome in regions with relatively low average GC content compared with the entire genome and contain mobile genetic elements. One of these regions of sequence divergence contained genes homologous to a mammalian cell entry (mce) operon. Our results indicate that closely related MAC mycobacteria can be distinguished from M. avium subsp. paratuberculosis by multiple clusters of divergent ORFs. PMID:15774884

Paustian, Michael L.; Kapur, Vivek; Bannantine, John P.

2005-01-01

114

Bibenzyls and dihydroisocoumarins from white salsify (Tragopogon porrifolius subsp. porrifolius).  

PubMed

A phytochemical investigation of three accessions of Tragopogon porrifolius L. subsp. porrifolius (Asteraceae, Lactuceae) yielded three new bibenzyl derivatives, 5,4'-dihydroxy-3-alpha-l-rhamnopyranosyl-(1-->3)-beta-d-xylopyranosyloxybibenzyl, 2-carboxyl-3,4'-dihydroxy-5-beta-d-xylopyranosyloxybibenzyl, tragopogonic acid (2'carboxyl-3',5',4''-trihydroxyphenylethanone) and three dihydroisocoumarin derivatives, including the new natural product 6-O-methylscorzocreticoside I. One of the isolated bibenzyl derivatives is considered to be a precursor to the biosynthesis of dihydroisocoumarins. Structures of new compounds were established by HR mass spectrometry, extensive 1D and 2D NMR spectroscopy, and CD spectroscopy. Moreover, radical scavenging activities of the polyphenolic compounds were measured using the 2,2-diphenyl-1-picrylhydrazyl assay; two of the bibenzyls showed moderate and two of the dihydroisocoumarins showed weak radical scavenging activities. The chemosystematic impact of bibenzyls and dihydroisocoumarins is discussed briefly. PMID:15964041

Zidorn, Christian; Lohwasser, Ulrike; Pschorr, Susanne; Salvenmoser, Daniela; Ongania, Karl-Hans; Ellmerer, Ernst P; Brner, Andreas; Stuppner, Hermann

2005-07-01

115

Antimicrobial phenolics and unusual glycerides from Helichrysum italicum subsp. microphyllum.  

PubMed

During a large-scale isolation campaign for the heterodimeric phloroglucinyl pyrone arzanol (1a) from Helichrysum italicum subsp. microphyllum, several new phenolics as well as an unusual class of lipids named santinols (5a-c, 6-8) have been characterized. Santinols are angeloylated glycerides characterized by the presence of branched acyl- or keto-acyl chains and represent a hitherto unreported class of plant lipids. The antibacterial activity of arzanol and of a selection of Helichrysum phenolics that includes coumarates, benzofurans, pyrones, and heterodimeric phloroglucinols was evaluated, showing that only the heterodimers showed potent antibacterial action against multidrug-resistant Staphylococcus aureus isolates. These observations validate the topical use of Helichrysum extracts to prevent wound infections, a practice firmly established in the traditional medicine of the Mediterranean area. PMID:23265253

Taglialatela-Scafati, Orazio; Pollastro, Federica; Chianese, Giuseppina; Minassi, Alberto; Gibbons, Simon; Arunotayanun, Warunya; Mabebie, Blessing; Ballero, Mauro; Appendino, Giovanni

2013-03-22

116

Molecular characterization of three Lactobacillus delbrueckii subsp. bulgaricus phages.  

PubMed

In this study, three phages infecting Lactobacillus delbrueckii subsp. bulgaricus, named Ld3, Ld17, and Ld25A, were isolated from whey samples obtained from various industrial fermentations. These phages were further characterized in a multifaceted approach: (i) biological and physical characterization through host range analysis and electron microscopy; (ii) genetic assessment through genome analysis; (iii) mass spectrometry analysis of the structural components of the phages; and (iv), for one phage, transcriptional analysis by Northern hybridization, reverse transcription-PCR, and primer extension. The three obtained phage genomes display high levels of sequence identity to each other and to genomes of the so-called group b L. delbrueckii phages c5, LL-Ku, and phiLdb, where some of the observed differences are believed to be responsible for host range variations. PMID:25002431

Casey, Eoghan; Mahony, Jennifer; O'Connell-Motherway, Mary; Bottacini, Francesca; Cornelissen, Anneleen; Neve, Horst; Heller, Knut J; Noben, Jean-Paul; Dal Bello, Fabio; van Sinderen, Douwe

2014-09-01

117

Humoral response to Mycobacterium avium subsp. avium in naturally infected ring-neck doves (Streptopelia risoria)  

E-print Network

Creation of a reliable and easy to use serologic test would greatly improve ante mortem diagnosis of Mycobacterium avium subsp. avium and aid in the control of avian mycobacteriosis, particularly in captive birds. In order to determine whether...

Gray, Patricia Lara-Lynn

2009-05-15

118

Comparative Genomics of Bifidobacterium animalis subsp. lactis Reveals a Strict Monophyletic Bifidobacterial Taxon  

PubMed Central

Strains of Bifidobacterium animalis subsp. lactis are extensively exploited by the food industry as health-promoting bacteria, although the genetic variability of members belonging to this taxon has so far not received much scientific attention. In this article, we describe the complete genetic makeup of the B. animalis subsp. lactis Bl12 genome and discuss the genetic relatedness of this strain with other sequenced strains belonging to this taxon. Moreover, a detailed comparative genomic analysis of B. animalis subsp. lactis genomes was performed, which revealed a closely related and isogenic nature of all currently available B. animalis subsp. lactis strains, thus strongly suggesting a closed pan-genome structure of this bacterial group. PMID:23645200

Milani, Christian; Duranti, Sabrina; Lugli, Gabriele Andrea; Bottacini, Francesca; Strati, Francesco; Arioli, Stefania; Foroni, Elena; Turroni, Francesca; van Sinderen, Douwe

2013-01-01

119

Lactococcus lactis subsp. lactis infection in waterfowl: first confirmation in animals.  

PubMed Central

We report the first description, confirmed by bacteriologic and molecular (polymerase chain reaction and pulsed-field gel electrophoresis) analysis, of an infection in animals caused by Lactococcus lactis subsp. lactis, affecting waterfowl. PMID:11747704

Goyache, J.; Vela, A. I.; Gibello, A.; Blanco, M. M.; Briones, V.; Gonzlez, S.; Tllez, S.; Ballesteros, C.; Domnguez, L.; Fernndez-Garayzbal, J. F.

2001-01-01

120

MAO-A inhibition profiles of some benzophenone glucosides from Gentiana verna subsp. pontica.  

PubMed

Gentiana verna L. subsp. pontica (Soltok.) Hayek, G. pyrenaica L., and G. verna L. subsp. balcanica Pritchard from Turkey were tested for their MAO-A inhibitory effects. A photometric peroxidase linked MAO-A bioassay performed on the H20 extracts prepared from the methanolic extracts of the title plants revealed the potential effect of G. verna subsp. pontica and three benzophenone glucosides; 2,3'-dihydroxy-4-methoxy-benzophenone-6-O-beta-glucopyranoside (1), 2,4,3',4'-tetrahydroxy-benzophenone-6-O-beta-glucopyranoside (maclurin-6-O-f-glucopyranoside) (2) and 2,4,3'-trihydroxy-benzophenone-6-O-beta-glucopyranoside (3) isolated from G. verna subsp. pontica. Among the benzophenone glucosides 1 and 2 exhibited significant inhibition of MAO-A (IC50 = 31.3 +/- 4 microM and 41 +/- 4.7 microM resp.). PMID:24868869

Kaya, Duygu; Jger, Anna K; Yalin, Funda N; Ersz, Tayfun

2014-04-01

121

Experimental Paratuberculosis in Calves following Inoculation with a Rabbit Isolate of Mycobacterium avium subsp. paratuberculosis  

PubMed Central

The role of wildlife species in the epidemiology of paratuberculosis has been the subject of increased research efforts following the discovery of natural paratuberculosis in free-living rabbits from farms in east Scotland. This paper describes the experimental inoculation of young calves with an isolate of Mycobacterium avium subsp. paratuberculosis recovered from a free-living rabbit. After a 6-month incubation period, all eight calves inoculated with the rabbit isolate had developed histopathological and/or microbiological evidence of M. avium subsp. paratuberculosis infection. Similar results were obtained from a group of calves infected with a bovine isolate of M. avium subsp. paratuberculosis. The virulence of the rabbit isolate for calves demonstrated in this study suggests that rabbits are capable of passing paratuberculosis to domestic ruminants and that wildlife reservoirs of M. avium subsp. paratuberculosis should therefore be considered when formulating control plans for the disease. PMID:11526132

Beard, P. M.; Stevenson, K.; Pirie, A.; Rudge, K.; Buxton, D.; Rhind, S. M.; Sinclair, M. C.; Wildblood, L. A.; Jones, D. G.; Sharp, J. M.

2001-01-01

122

Exploring the Genome of Cheese Starter Lactic Acid Bacterium Lactococcus lactis subsp. lactis CECT 4433.  

PubMed

Here, we present the draft genome sequences of Lactococcus lactis subsp. lactis CECT 4433, a cheese fermentation starter strain. The genome provides further insight into the genomic plasticity, biocomplexity (including gene strain specifics), and evolution of these genera. PMID:25395632

Tschoeke, Diogo Antonio; Moreira, Ana Paula B; Chimetto Tonon, Luciane A; de Mesquita, Milene Miranda A; Gregoracci, Gustavo B; Gomez-Gil, Bruno; Valle, Rogrio; Thompson, Cristiane C; Thompson, Fabiano L

2014-01-01

123

Tomato Transcriptional Changes in Response to Clavibacter michiganensis subsp. michiganensis Reveal  

E-print Network

Tomato Transcriptional Changes in Response to Clavibacter michiganensis subsp. michiganensis Reveal, causing bacterial wilt and canker disease in tomato (Solanum lycopersicum). Host responses to gram in tomato are largely unexplored. To investigate plant responses activated during this compatible

Sessa, Guido

124

Capsular exopolysaccharide biosynthesis gene of Propionibacterium freudenreichii subsp. shermanii.  

PubMed

In the dairy industry, exopolysaccharides (EPS) contribute to improving the texture and viscosity of cheese and yoghurt and also receive increasing attention because of their beneficial properties for health. For lactic acid bacteria, the production of EPS is well studied. However, for dairy propionibacteria the biosynthesis of EPS is poorly documented. A polysaccharide synthase-encoding gene was identified in the genome of Propionibacterium freudenreichii subsp. shermanii TL 34 (CIP 103027). This gene best aligns with Tts, the polysaccharide synthase gene of Streptococcus pneumoniae type 37 that is responsible for the production of a beta-glucan capsular polysaccharide. PCR amplification showed the presence of an internal fragment of this gene in twelve strains of P. freudenreichii subsp. shermanii with a ropy phenotype in YEL+ medium. The gene sequence is highly conserved, as less than 1% of nucleotides differed among the 10 strains containing the complete gtf gene. The same primers failed to detect the gene in Propionibacterium acidipropionici strain TL 47, which is known to excrete exopolysaccharides in milk. The presence of (1-->3, 1-->2)-beta-d-glucan capsule was demonstrated for 7 out of 12 strains by agglutination with a S. pneumoniae-type 37-specific antiserum. The presence of mRNA corresponding to the gene was detected by RT-PCR in three strains at both exponential and stationary growth phases. This work represents the first identification of a polysaccharide synthase gene of P. freudenreichii, and further studies will be undertaken to elucidate the role of capsular EPS. PMID:18524407

Deutsch, Stphanie-Marie; Falentin, Hlne; Dols-Lafargue, Marguerite; Lapointe, Gisle; Roy, Denis

2008-07-31

125

Determination of kinetic properties of polyphenol oxidase from Thymus ( Thymus longicaulis subsp. chaubardii var. chaubardii)  

Microsoft Academic Search

A partial characterization of polyphenol oxidase (PPO) activity of Thymus longicaulis subsp. chaubardii var. chaubardii is described. Polyphenol oxidase of Thymus was isolated by (NH4)2SO4 precipitation and dialysis. The effects of substrate specificity, pH, temperature, heat-inactivation and glutathione inhibitor on polyphenol oxidase activity obtained from T. longicaulis subsp. chaubardii var. chaubardii were investigated. Polyphenol oxidase showed activity toward catechol, 4-methylcatechol

Serap Dogan; Mehmet Dogan

2004-01-01

126

The Citrate Transport System of Lactococcus lactis subsp. lactis biovar diacetylactis Is Induced by Acid Stress  

Microsoft Academic Search

Citrate transport in Lactococcus lactis subsp. lactis biovar diacetylactis is catalyzed by citrate permease P (CitP), which is encoded by the plasmidic citP gene. We have shown previously that citP is included in the citQRP operon, which is mainly transcribed from the P1 promoter in L. lactis subsp. lactis biovar diacetylactis. Furthermore, transcription of citQRP and citrate transport are not

NIEVES GARCIA-QUINTANS; CHRISTIAN MAGNI; DIEGO DE MENDOZA; PALOMA LOPEZ

1998-01-01

127

Local evolution of obligate autogamy in Epipactis helleborine subsp. neerlandica (Orchidaceae)  

Microsoft Academic Search

Isozyme analysis was used to assess the origin of the DanishEpipactis renzii, a local endemic of open coastal dunes. It seems to have evolved recently in several local populations of the more or less allogamousE. helleborine subsp.neerlandica. The obligately autogamousE. renzii is restricted to the easternmost part of the Danish range ofE. helleborine subsp.neerlandica, indicating that transition to obligate autogamy

H. . Pedersen; B. K. Ehlers

2000-01-01

128

Die Unkraut-Hirse ( Panicum miliaceum subsp. ruderale ) neue Tatsachen und Befunde  

Microsoft Academic Search

The Weed-Broomcorn Millet,Panicum miliaceum L. subsp.ruderale (Kitag.)Tzvelev, until now observed only in Asiatic countries, is also present in Austria (C. Europe). Whereas the cultivatedP. miliaceum subsp.miliaceum, devoid of all natural dispersal ability, cannot actively spread, the Weed-Broomcorn Millet can do so successfully and is increasingly infesting fields ofZea mays. Its spikelets disarticulate at maturity below the glumes, and moreover the

Hildemar Scholz

1983-01-01

129

Biosynthetic origin of the nitrogen atom in cyanamide in Vicia villosa subsp. varia  

Microsoft Academic Search

Natural cyanamide (NH2CN) has recently been found in three Leguminosae plants: Vicia villosa subsp. varia, Vicia cracca and Robinia pseudo-acacia. As cyanamide has long been thought to be absent in nature, its physiological role and biosynthesis are totally unknown. In the present study, we demonstrated the incorporation of N from [N]nitrate and [N]ammonium into cyanamide using shoots of V.villosa subsp.

Tsunashi Kamo; Kenji Kato; Shun Abe; Mitsuru Hirota; Hiroko Yamaya; Syuntaro Hiradate; Yoshiharu Fujii

2009-01-01

130

Decreased Toxicity of Bacillus thuringiensis subsp. israelensis to Mosquito Larvae after Contact with Leaf Litter  

PubMed Central

Bacillus thuringiensis subsp. israelensis is a bacterium producing crystals containing Cry and Cyt proteins, which are toxic for mosquito larvae. Nothing is known about the interaction between crystal toxins and decaying leaf litter, which is a major component of several mosquito breeding sites and represents an important food source. In the present work, we investigated the behavior of B. thuringiensis subsp. israelensis toxic crystals sprayed on leaf litter. In the presence of leaf litter, a 60% decrease in the amount of Cyt toxin detectable by immunology (enzyme-linked immunosorbent assays [ELISAs]) was observed, while the respective proportions of Cry toxins were not affected. The toxicity of Cry toxins toward Aedes aegypti larvae was not affected by leaf litter, while the synergistic effect of Cyt toxins on all B. thuringiensis subsp. israelensis Cry toxins was decreased by about 20% when mixed with leaf litter. The toxicity of two commercial B. thuringiensis subsp. israelensis strains (VectoBac WG and VectoBac 12AS) and a laboratory-produced B. thuringiensis subsp. israelensis strain decreased by about 70% when mixed with leaf litter. Taken together, these results suggest that Cyt toxins interact with leaf litter, resulting in a decreased toxicity of B. thuringiensis subsp. israelensis in litter-rich environments and thereby dramatically reducing the efficiency of mosquitocidal treatments. PMID:22610426

Stalinski, Renaud; Kersusan, Dylann; Veyrenc, Sylvie; David, Jean-Philippe; Reynaud, Stphane; Desprs, Laurence

2012-01-01

131

Adaptation and response of Bifidobacterium animalis subsp. lactis to bile: a proteomic and physiological approach.  

PubMed

Bile salts are natural detergents that facilitate the digestion and absorption of the hydrophobic components of the diet. However, their amphiphilic nature makes them very inhibitory for bacteria and strongly influences bacterial survival in the gastrointestinal tract. Adaptation to and tolerance of bile stress is therefore crucial for the persistence of bacteria in the human colonic niche. Bifidobacterium animalis subsp. lactis, a probiotic bacterium with documented health benefits, is applied largely in fermented dairy products. In this study, the effect of bile salts on proteomes of B. animalis subsp. lactis IPLA 4549 and its bile-resistant derivative B. animalis subsp. lactis 4549dOx was analyzed, leading to the identification of proteins which may represent the targets of bile salt response and adaptation in B. animalis subsp. lactis. The comparison of the wild-type and the bile-resistant strain responses allowed us to hypothesize about the resistance mechanisms acquired by the derivative resistant strain and about the bile salt response in B. animalis subsp. lactis. In addition, significant differences in the levels of metabolic end products of the bifid shunt and in the redox status of the cells were also detected, which correlate with some differences observed between the proteomes. These results indicate that adaptation and response to bile in B. animalis subsp. lactis involve several physiological mechanisms that are jointly dedicated to reduce the deleterious impact of bile on the cell's physiology. PMID:17827318

Snchez, Borja; Champomier-Vergs, Marie-Christine; Stuer-Lauridsen, Birgitte; Ruas-Madiedo, Patricia; Anglade, Patricia; Baraige, Fabienne; de los Reyes-Gaviln, Clara G; Johansen, Eric; Zagorec, Monique; Margolles, Abelardo

2007-11-01

132

Tomato Fruit and Seed Colonization by Clavibacter michiganensis subsp. michiganensis through External and Internal Routes  

PubMed Central

The Gram-positive bacterium Clavibacter michiganensis subsp. michiganensis, causal agent of bacterial wilt and canker of tomato, is an economically devastating pathogen that inflicts considerable damage throughout all major tomato-producing regions. Annual outbreaks continue to occur in New York, where C. michiganensis subsp. michiganensis spreads via infected transplants, trellising stakes, tools, and/or soil. Globally, new outbreaks can be accompanied by the introduction of contaminated seed stock; however, the route of seed infection, especially the role of fruit lesions, remains undefined. In order to investigate the modes of seed infection, New York C. michiganensis subsp. michiganensis field strains were stably transformed with a gene encoding enhanced green fluorescent protein (eGFP). A constitutively eGFP-expressing virulent C. michiganensis subsp. michiganensis isolate, GCMM-22, was used to demonstrate that C. michiganensis subsp. michiganensis could not only access seeds systemically through the xylem but also externally through tomato fruit lesions, which harbored high intra- and intercellular populations. Active movement and expansion of bacteria into the fruit mesocarp and nearby xylem vessels followed, once the fruits began to ripen. These results highlight the ability of C. michiganensis subsp. michiganensis to invade tomato fruits and seeds through multiple entry routes. PMID:24014525

Tancos, Matthew A.; Chalupowicz, Laura; Barash, Isaac; Manulis-Sasson, Shulamit

2013-01-01

133

Adaptation and Response of Bifidobacterium animalis subsp. lactis to Bile: a Proteomic and Physiological Approach?  

PubMed Central

Bile salts are natural detergents that facilitate the digestion and absorption of the hydrophobic components of the diet. However, their amphiphilic nature makes them very inhibitory for bacteria and strongly influences bacterial survival in the gastrointestinal tract. Adaptation to and tolerance of bile stress is therefore crucial for the persistence of bacteria in the human colonic niche. Bifidobacterium animalis subsp. lactis, a probiotic bacterium with documented health benefits, is applied largely in fermented dairy products. In this study, the effect of bile salts on proteomes of B. animalis subsp. lactis IPLA 4549 and its bile-resistant derivative B. animalis subsp. lactis 4549dOx was analyzed, leading to the identification of proteins which may represent the targets of bile salt response and adaptation in B. animalis subsp. lactis. The comparison of the wild-type and the bile-resistant strain responses allowed us to hypothesize about the resistance mechanisms acquired by the derivative resistant strain and about the bile salt response in B. animalis subsp. lactis. In addition, significant differences in the levels of metabolic end products of the bifid shunt and in the redox status of the cells were also detected, which correlate with some differences observed between the proteomes. These results indicate that adaptation and response to bile in B. animalis subsp. lactis involve several physiological mechanisms that are jointly dedicated to reduce the deleterious impact of bile on the cell's physiology. PMID:17827318

Sanchez, Borja; Champomier-Verges, Marie-Christine; Stuer-Lauridsen, Birgitte; Ruas-Madiedo, Patricia; Anglade, Patricia; Baraige, Fabienne; de los Reyes-Gavilan, Clara G.; Johansen, Eric; Zagorec, Monique; Margolles, Abelardo

2007-01-01

134

Tomato fruit and seed colonization by Clavibacter michiganensis subsp. michiganensis through external and internal routes.  

PubMed

The Gram-positive bacterium Clavibacter michiganensis subsp. michiganensis, causal agent of bacterial wilt and canker of tomato, is an economically devastating pathogen that inflicts considerable damage throughout all major tomato-producing regions. Annual outbreaks continue to occur in New York, where C. michiganensis subsp. michiganensis spreads via infected transplants, trellising stakes, tools, and/or soil. Globally, new outbreaks can be accompanied by the introduction of contaminated seed stock; however, the route of seed infection, especially the role of fruit lesions, remains undefined. In order to investigate the modes of seed infection, New York C. michiganensis subsp. michiganensis field strains were stably transformed with a gene encoding enhanced green fluorescent protein (eGFP). A constitutively eGFP-expressing virulent C. michiganensis subsp. michiganensis isolate, GCMM-22, was used to demonstrate that C. michiganensis subsp. michiganensis could not only access seeds systemically through the xylem but also externally through tomato fruit lesions, which harbored high intra- and intercellular populations. Active movement and expansion of bacteria into the fruit mesocarp and nearby xylem vessels followed, once the fruits began to ripen. These results highlight the ability of C. michiganensis subsp. michiganensis to invade tomato fruits and seeds through multiple entry routes. PMID:24014525

Tancos, Matthew A; Chalupowicz, Laura; Barash, Isaac; Manulis-Sasson, Shulamit; Smart, Christine D

2013-11-01

135

Decreased toxicity of Bacillus thuringiensis subsp. israelensis to mosquito larvae after contact with leaf litter.  

PubMed

Bacillus thuringiensis subsp. israelensis is a bacterium producing crystals containing Cry and Cyt proteins, which are toxic for mosquito larvae. Nothing is known about the interaction between crystal toxins and decaying leaf litter, which is a major component of several mosquito breeding sites and represents an important food source. In the present work, we investigated the behavior of B. thuringiensis subsp. israelensis toxic crystals sprayed on leaf litter. In the presence of leaf litter, a 60% decrease in the amount of Cyt toxin detectable by immunology (enzyme-linked immunosorbent assays [ELISAs]) was observed, while the respective proportions of Cry toxins were not affected. The toxicity of Cry toxins toward Aedes aegypti larvae was not affected by leaf litter, while the synergistic effect of Cyt toxins on all B. thuringiensis subsp. israelensis Cry toxins was decreased by about 20% when mixed with leaf litter. The toxicity of two commercial B. thuringiensis subsp. israelensis strains (VectoBac WG and VectoBac 12AS) and a laboratory-produced B. thuringiensis subsp. israelensis strain decreased by about 70% when mixed with leaf litter. Taken together, these results suggest that Cyt toxins interact with leaf litter, resulting in a decreased toxicity of B. thuringiensis subsp. israelensis in litter-rich environments and thereby dramatically reducing the efficiency of mosquitocidal treatments. PMID:22610426

Tetreau, Guillaume; Stalinski, Renaud; Kersusan, Dylann; Veyrenc, Sylvie; David, Jean-Philippe; Reynaud, Stphane; Desprs, Laurence

2012-08-01

136

Model-based analysis of avoidance of ozone stress by stomatal closure in Siebold's beech (Fagus crenata)  

PubMed Central

Background and Aims Resistance of plants to ozone stress can be classified as either avoidance or tolerance. Avoidance of ozone stress may be explained by decreased stomatal conductance during ozone exposure because stomata are the principal interface for entry of ozone into plants. In this study, a coupled photosynthesisstomatal model was modified to test whether the presence of ozone can induce avoidance of ozone stress by stomatal closure. Methods The response of Siebold's beech (Fagus crenata), a representative deciduous tree species, to ozone was studied in a free-air ozone exposure experiment in Japan. Photosynthesis and stomatal conductance were measured under ambient and elevated ozone. An optimization model of stomata involving water, CO2 and ozone flux was tested using the leaf gas exchange data. Key Results The data suggest that there are two phases in the avoidance of ozone stress via stomatal closure for Siebold's beech: (1) in early summer ozone influx is efficiently limited by a reduction in stomatal conductance, without any clear effect on photosynthetic capacity; and (2) in late summer and autumn the efficiency of ozone stress avoidance was decreased because the decrease in stomatal conductance was small and accompanied by an ozone-induced decline of photosynthetic capacity. Conclusions Ozone-induced stomatal closure in Siebold's beech during early summer reduces ozone influx and allows the maximum photosynthetic capacity to be reached, but is not sufficient in older leaves to protect the photosynthetic system. PMID:23904447

Hoshika, Yasutomo; Watanabe, Makoto; Inada, Naoki; Koike, Takayoshi

2013-01-01

137

Phosphite protects Fagus sylvatica seedlings towards Phytophthora plurivora via local toxicity, priming and facilitation of pathogen recognition.  

PubMed

Phytophthora plurivora causes severe damage on Fagus sylvatica and is responsible for the extensive decline of European Beech throughout Europe. Unfortunately, no effective treatment against this disease is available. Phosphite (Phi) is known to protect plants against Phytophthora species; however, its mode of action towards P. plurivora is still unknown. To discover the effect of Phi on root infection, leaves were sprayed with Phi and roots were subsequently inoculated with P. plurivora zoospores. Seedling physiology, defense responses, colonization of root tissue by the pathogen and mortality were monitored. Additionally the Phi concentration in roots was quantified. Finally, the effect of Phi on mycelial growth and zoospore formation was recorded. Phi treatment was remarkably efficient in protecting beech against P. plurivora; all Phi treated plants survived infection. Phi treated and infected seedlings showed a strong up-regulation of several defense genes in jasmonate, salicylic acid and ethylene pathways. Moreover, all physiological parameters measured were comparable to control plants. The local Phi concentration detected in roots was high enough to inhibit pathogen growth. Phi treatment alone did not harm seedling physiology or induce defense responses. The up-regulation of defense genes could be explained either by priming or by facilitation of pathogen recognition of the host. PMID:24489973

Dalio, Ronaldo J D; Fleischmann, Frank; Humez, Martina; Osswald, Wolfgang

2014-01-01

138

Phosphite Protects Fagus sylvatica Seedlings towards Phytophthora plurivora via Local Toxicity, Priming and Facilitation of Pathogen Recognition  

PubMed Central

Phytophthora plurivora causes severe damage on Fagus sylvatica and is responsible for the extensive decline of European Beech throughout Europe. Unfortunately, no effective treatment against this disease is available. Phosphite (Phi) is known to protect plants against Phytophthora species; however, its mode of action towards P. plurivora is still unknown. To discover the effect of Phi on root infection, leaves were sprayed with Phi and roots were subsequently inoculated with P. plurivora zoospores. Seedling physiology, defense responses, colonization of root tissue by the pathogen and mortality were monitored. Additionally the Phi concentration in roots was quantified. Finally, the effect of Phi on mycelial growth and zoospore formation was recorded. Phi treatment was remarkably efficient in protecting beech against P. plurivora; all Phi treated plants survived infection. Phi treated and infected seedlings showed a strong up-regulation of several defense genes in jasmonate, salicylic acid and ethylene pathways. Moreover, all physiological parameters measured were comparable to control plants. The local Phi concentration detected in roots was high enough to inhibit pathogen growth. Phi treatment alone did not harm seedling physiology or induce defense responses. The up-regulation of defense genes could be explained either by priming or by facilitation of pathogen recognition of the host. PMID:24489973

Dalio, Ronaldo J. D.; Fleischmann, Frank; Humez, Martina; Osswald, Wolfgang

2014-01-01

139

Genetic variation in Mediterranean Helichrysum italicum (Asteraceae; Gnaphalieae): do disjunct populations of subsp. microphyllum have a common origin?  

PubMed

The yellow-flowered everlasting daisy Helichrysum italicum (Asteraceae, Gnaphalieae) is widely distributed in the Mediterranean basin, where it grows in continuous and widespread populations in diverse open habitats. Helichrysum italicum subsp. microphyllum has a disjunct distribution in the Balearic Islands (Majorca and Dragonera), Corsica, Sardinia, Crete and Cyprus. Numerous morphological intermediates between subsp. italicum and subsp. microphyllum are known from Corsica, where the two subspecies co-occur. The aims of the study were to investigate if subsp. microphyllum has a common origin, constituting an independent gene pool from subsp. italicum, or if the morphological differences between subsp. microphyllum and subsp. italicum have arisen independently in different locations from a common wider gene pool. Our analyses of AFLP, cpDNA sequences and morphological characters show that there is geographic structure to the genetic variation within H.italicum, with eastern and western Mediterranean groups, which do not correspond with the division into subsp. microphyllum and subsp. italicum as currently circumscribed. Local selection on quantitative trait loci provides sufficient explanation for the morphological divergence observed and is consistent with genetic data. Within the western Mediterranean group of the species we found considerable polymorphism in chloroplast DNA sequences among and within some populations. Comparison with chloroplast DNA sequences from other Helichrysum species showed that some chloroplast haplotypes are shared across species. PMID:21668609

Galbany-Casals, M; Blanco-Moreno, J M; Garcia-Jacas, N; Breitwieser, I; Smissen, R D

2011-07-01

140

Bifidobacterium animalis subsp. lactis ATCC 27673 Is a Genomically Unique Strain within Its Conserved Subspecies  

PubMed Central

Many strains of Bifidobacterium animalis subsp. lactis are considered health-promoting probiotic microorganisms and are commonly formulated into fermented dairy foods. Analyses of previously sequenced genomes of B. animalis subsp. lactis have revealed little genetic diversity, suggesting that it is a monomorphic subspecies. However, during a multilocus sequence typing survey of Bifidobacterium, it was revealed that B. animalis subsp. lactis ATCC 27673 gave a profile distinct from that of the other strains of the subspecies. As part of an ongoing study designed to understand the genetic diversity of this subspecies, the genome of this strain was sequenced and compared to other sequenced genomes of B. animalis subsp. lactis and B. animalis subsp. animalis. The complete genome of ATCC 27673 was 1,963,012 bp, contained 1,616 genes and 4 rRNA operons, and had a G+C content of 61.55%. Comparative analyses revealed that the genome of ATCC 27673 contained six distinct genomic islands encoding 83 open reading frames not found in other strains of the same subspecies. In four islands, either phage or mobile genetic elements were identified. In island 6, a novel clustered regularly interspaced short palindromic repeat (CRISPR) locus which contained 81 unique spacers was identified. This type I-E CRISPR-cas system differs from the type I-C systems previously identified in this subspecies, representing the first identification of a different system in B. animalis subsp. lactis. This study revealed that ATCC 27673 is a strain of B. animalis subsp. lactis with novel genetic content and suggests that the lack of genetic variability observed is likely due to the repeated sequencing of a limited number of widely distributed commercial strains. PMID:23995933

Loquasto, Joseph R.; Barrangou, Rodolphe; Dudley, Edward G.; Stahl, Buffy; Chen, Chun

2013-01-01

141

Stability of the delta-endotoxin gene from Bacillus thuringiensis subsp. kurstaki in a recombinant strain of Clavibacter xyli subsp. cynodontis.  

PubMed Central

Deletion of chromosomally inserted gene sequences from Clavibacter xyli subsp. cynodontis, a xylem-inhabiting endophyte, was studied in vitro and in planta. We found that nonreplicating plasmid pCG610, which conferred resistance to kanamycin and tetracycline and contained segments of C. xyli subsp. cynodontis genomic DNA, integrated into a homologous sequence in the bacterial chromosome. In addition, pCG610 contains two copies of the gene encoding the CryIA(c) insecticidal protein of Bacillus thuringiensis subsp. kurstaki HD73. Using drug resistance phenotypes and specific DNA probes, we found that the loss of all three genes arose both in vitro under nonselective conditions and in planta. The resulting segregants are probably formed by recombination between the repeated DNA sequences flanking pCG610 that resulted from the integration event into the chromosome. Eventually, segregants predominated in the bacterial population. The loss of the integrated plasmid from C. xyli subsp. cynodontis revealed a possible approach for decreasing the environmental consequences of recombinant bacteria for agricultural use. Images PMID:1664710

Turner, J T; Lampel, J S; Stearman, R S; Sundin, G W; Gunyuzlu, P; Anderson, J J

1991-01-01

142

PRELIMINARY STUDY ON LOCALISATION OF MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS IN UDDER OF SEROPOSITIVE EWES STUDIO PRELIMINARE DELLA LOCALIZZAZIONE DI MYCOBACTERIUM AVIUM SUBSP. PARATUBERCULOSIS NELLA MAMMELLA DI PECORE SIEROPOSITIVE  

Microsoft Academic Search

In order to evaluate the presence of Mycobacterium avium subsp. paratuberculosis (MAP) in milk and mammary apparatus of seropositive ewes, samples of mammary gland and supramammary lymph nodes were collected from 20 Comisana breed sheep. Milk of 14 out of 20 ewes was available for sampling. Intestine and mesenteric lymph nodes were also collected in order to confirm MAP infection.

S. Preziuso; M. L. Marenzoni; A. R. Attili; C. Valente; V. Cuteri

143

Flow Cytometric Detection of Mycobacterium avium subsp. paratuberculosis-Specific Antibodies in Experimentally Infected and Naturally Exposed Calves  

PubMed Central

A desirable test to diagnose infections with Mycobacterium avium subsp. paratuberculosis facilitates identification of infected cattle prior to the state of M. avium subsp. paratuberculosis shedding. This study aimed at adjusting a flow cytometry (FC)-based assay, using intact M. avium subsp. paratuberculosis bacteria as the antigen, for diagnosis of M. avium subsp. paratuberculosis infections in calves. Serum samples were collected from experimentally infected (n = 12) and naturally exposed (n = 32) calves. Samples from five calves from positive dams were analyzed to determine the dynamics of maternal antibodies. Samples from adult cattle with defined infection status served as the standard (18 M. avium subsp. paratuberculosis shedders, 22 M. avium subsp. paratuberculosis free). After preadsorption with Mycobacterium phlei, sera were incubated with M. avium subsp. paratuberculosis and M. avium subsp. avium bacterial suspensions, respectively, followed by the separate detection of bovine IgG, IgG1, IgG2, and IgM attached to the bacterial surface. M. avium subsp. paratuberculosis-specific sample/positive (S/P) ratios were compared to enzyme-linked immunosorbent assay (ELISA) S/P ratios. In adult cattle, the FC assay for IgG1 had a sensitivity of 78% at a specificity of 100%. Maternally acquired antibodies could be detected in calves up to 121 days of life. While all but two sera taken at day 100 10 postnatum from naturally exposed calves tested negative, elevated S/P ratios (IgG and IgG1) became detectable from 44 and 46 weeks postinoculation onwards in two calves infected experimentally. Even with the optimized FC assay, M. avium subsp. paratuberculosis-specific antibodies can only occasionally be detected in infected calves less than 12 months of age. The failure to detect such antibodies apparently reflects the distinct immunobiology of M. avium subsp. paratuberculosis infections rather than methodological constraints. PMID:23885032

Bridger, P. S.; Bulun, H.; Fischer, M.; Akineden, .; Seeger, T.; Barth, S.; Henrich, M.; Doll, K.; Blte, M.; Menge, C.; Bauerfeind, R.

2013-01-01

144

Anti-tumour activity of Digitalis purpurea L. subsp. heywoodii.  

PubMed

Recent research has shown the anticancer effects of digitalis compounds suggesting their possible use in medical oncology. Four extracts obtained from the leaves of Digitalis purpurea subsp. heywoodii have been assessed for cytotoxic activity against three human cancer cell lines, using the SRB assay. All of them showed high cytotoxicity, producing IC50 values in the 0.78 - 15 microg/mL range with the methanolic extract being the most active, in non toxic concentrations. Steroid glycosides (gitoxigenin derivatives) were detected in this methanolic extract. Gitoxigenin and gitoxin were evaluated in the SRB assay using the three human cancer cell lines, showing IC50 values in the 0.13 - 2.8 microM range, with the renal adenocarcinoma cancer cell line (TK-10) being the most sensitive one. Morphological apoptosis evaluation of the methanolic extract and both compounds on the TK-10 cell line showed that their cytotoxicity was mediated by an apoptotic effect. Finally, possible mechanisms involved in apoptosis induction by digitalis compounds are discussed. PMID:14531018

Lpez-Lzaro, Miguel; Palma De La Pea, Nieves; Pastor, Nuria; Martn-Cordero, Carmen; Navarro, Eduardo; Corts, Felipe; Ayuso, Mara Jess; Toro, Mara Victoria

2003-08-01

145

Bacillus thuringiensis subsp. israelensis and its dipteran-specific toxins.  

PubMed

Bacillus thuringiensis subsp. israelensis (Bti) is the first Bacillus thuringiensis to be found and used as an effective biological control agent against larvae of many mosquito and black fly species around the world. Its larvicidal activity resides in four major (of 134, 128, 72 and 27 kDa) and at least two minor (of 78 and 29 kDa) polypeptides encoded respectively by cry4Aa, cry4Ba, cry11Aa, cyt1Aa, cry10Aa and cyt2Ba, all mapped on the 128 kb plasmid known as pBtoxis. These six ?-endotoxins form a complex parasporal crystalline body with remarkably high, specific and different toxicities to Aedes, Culex and Anopheles larvae. Cry toxins are composed of three domains (perforating domain I and receptor binding II and III) and create cation-selective channels, whereas Cyts are composed of one domain that acts as well as a detergent-like membrane perforator. Despite the low toxicities of Cyt1Aa and Cyt2Ba alone against exposed larvae, they are highly synergistic with the Cry toxins and hence their combinations prevent emergence of resistance in the targets. The lack of significant levels of resistance in field mosquito populations treated for decades with Bti-bioinsecticide suggests that this bacterium will be an effective biocontrol agent for years to come. PMID:24686769

Ben-Dov, Eitan

2014-04-01

146

Bacillus thuringiensis subsp. israelensis and Its Dipteran-Specific Toxins  

PubMed Central

Bacillus thuringiensis subsp. israelensis (Bti) is the first Bacillus thuringiensis to be found and used as an effective biological control agent against larvae of many mosquito and black fly species around the world. Its larvicidal activity resides in four major (of 134, 128, 72 and 27 kDa) and at least two minor (of 78 and 29 kDa) polypeptides encoded respectively by cry4Aa, cry4Ba, cry11Aa, cyt1Aa, cry10Aa and cyt2Ba, all mapped on the 128 kb plasmid known as pBtoxis. These six ?-endotoxins form a complex parasporal crystalline body with remarkably high, specific and different toxicities to Aedes, Culex and Anopheles larvae. Cry toxins are composed of three domains (perforating domain I and receptor binding II and III) and create cation-selective channels, whereas Cyts are composed of one domain that acts as well as a detergent-like membrane perforator. Despite the low toxicities of Cyt1Aa and Cyt2Ba alone against exposed larvae, they are highly synergistic with the Cry toxins and hence their combinations prevent emergence of resistance in the targets. The lack of significant levels of resistance in field mosquito populations treated for decades with Bti-bioinsecticide suggests that this bacterium will be an effective biocontrol agent for years to come. PMID:24686769

Ben-Dov, Eitan

2014-01-01

147

Immunological response to Mycobacterium avium subsp. paratuberculosis in chickens  

PubMed Central

Abstract Enzyme-linked immunosorbent assay (ELISA) and culture are 2 common diagnostic tests for detecting Mycobacterium avium subsp. paratuberculosis (Map) in Johnes disease, but they are not as sensitive as polymerase chain reaction (PCR). However, inhibitors can coextract with the target DNA and cause interference in PCR. Development of an immune capture assay followed by PCR amplification can alleviate this problem. In this study, we were able to induce an immune response in chickens using heat or formalin inactivated Map. The purified immunoglobulin (Ig)Y has a molecular weight of 160 kDa. The titers were at 1:6400 and 1:12 800 at weeks 5 to 6 and 8 to 9, respectively, as determined by the IDEXX modified ELISA kit for Johnes disease. The IgY produced from inactivated bacterial cells had no effect on its ability to recognize live Map cells as illustrated by immunofluorescence assay and immune capture PCR results. PMID:15581226

2004-01-01

148

Compared effects of competition by grasses ( Graminoids ) and broom ( Cytisus scoparius ) on growth and functional traits of beech saplings ( Fagus sylvatica )  

Microsoft Academic Search

\\u000a \\u000a The effect of two weeds (grasses and broom, Cytisus scoparius) competition on the growth and functional traits of European beech saplings (Fagus sylvatica) was investigated in an experimental plantation in the French Massif central.\\u000a \\u000a \\u000a \\u000a \\u000a \\u000a \\u000a We hypothesized that grasses would have a much more harmful effect than broom on beech growth through strong competition\\u000a for soil water

Damien Provendier; Philippe Balandier

2008-01-01

149

Leaf traits, shoot growth and seed production in mature Fagus sylvatica trees after 8 years of CO2 enrichment  

PubMed Central

Background and Aims Masting, i.e. synchronous but highly variable interannual seed production, is a strong sink for carbon and nutrients. It may, therefore, compete with vegetative growth. It is currently unknown whether increased atmospheric CO2 concentrations will affect the carbon balance (or that of other nutrients) between reproduction and vegetative growth of forest species. In this study, reproduction and vegetative growth of shoots of mature beech (Fagus sylvatica) trees grown at ambient and elevated atmospheric CO2 concentrations were quantified. It was hypothesized that within a shoot, fruiting has a negative effect on vegetative growth, and that this effect is ameliorated at increased CO2 concentrations. Methods Reproduction and its competition with leaf and shoot production were examined during two masting events (in 2007 and 2009) in F. sylvatica trees that had been exposed to either ambient or elevated CO2 concentrations (530 mol mol?1) for eight consecutive years, between 2000 and 2008. Key Results The number of leaves per shoot and the length of terminal shoots was smaller or shorter in the two masting years compared with the one non-masting year (2008) investigated, but they were unaffected by elevated CO2 concentrations. The dry mass of terminal shoots was approx. 2-fold lower in the masting year (2007) than in the non-masting year in trees growing at ambient CO2 concentrations, but this decline was not observed in trees exposed to elevated CO2 concentrations. In both the CO2 treatments, fruiting significantly decreased nitrogen concentration by 25 % in leaves and xylem tissue of 1- to 3-year-old branches in 2009. Conclusions Our findings indicate that there is competition for resources between reproduction and shoot growth. Elevated CO2 concentrations reduced this competition, indicating effects on the balance of resource allocation between reproduction and vegetative growth in shoots with rising atmospheric CO2 concentrations. PMID:21493641

Han, Qingmin; Kabeya, Daisuke; Hoch, Gunter

2011-01-01

150

Comparison of pollen gene flow among four European beech (Fagus sylvatica L.) populations characterized by different management regimes  

PubMed Central

The study of the dispersal capability of a species can provide essential information for the management and conservation of its genetic variability. Comparison of gene flow rates among populations characterized by different management and evolutionary histories allows one to decipher the role of factors such as isolation and tree density on gene movements. We used two paternity analysis approaches and different strategies to handle the possible presence of genotyping errors to obtain robust estimates of pollen flow in four European beech (Fagus sylvatica L.) populations from Austria and France. In each country one of the two plots is located in an unmanaged forest; the other plots are managed with a shelterwood system and inside a colonization area (in Austria and France, respectively). The two paternity analysis approaches provided almost identical estimates of gene flow. In general, we found high pollen immigration (?75% of pollen from outside), with the exception of the plot from a highly isolated forest remnant (?50%). In the two unmanaged plots, the average within-population pollen dispersal distances (from 80 to 184?m) were higher than previously estimated for beech. From the comparison between the Austrian managed and unmanaged plots, that are only 500?m apart, we found no evidence that either gene flow or reproductive success distributions were significantly altered by forest management. The investigated phenotypic traits (crown area, height, diameter and flowering phenology) were not significantly related with male reproductive success. Shelterwood seems to have an effect on the distribution of within-population pollen dispersal distances. In the managed plot, pollen dispersal distances were shorter, possibly because adult tree density is three-fold (163 versus 57 trees per hectare) with respect to the unmanaged one. PMID:21897442

Piotti, A; Leonardi, S; Buiteveld, J; Geburek, T; Gerber, S; Kramer, K; Vettori, C; Vendramin, G G

2012-01-01

151

Pacific Ocean and Japan Sea ecotypes of Japanese beech (Fagus crenata) differ in photosystem responses to continuous high light.  

PubMed

Two ecotypes of Japanese beech (Fagus crenata Blume), the Pacific Ocean type (PAO) and the Japan Sea type (JAS), show different responses to high solar irradiance. When PAO and JAS saplings were grown in continuous high-light (H), leaves of JAS became pale green. To elucidate this phenomenon, we investigated in vivo photochemistry based on pigment concentrations of Photosystem (PS) I and PS II and Western blot analysis. In JAS-H leaves, the amount of D1-protein decreased, resulting in decreases in the maximal quantum yield of PS II (F(v)/F(m)) and electron transport rate, whereas PAO-H leaves maintained high activities. The PS I photochemistry determined by measurement of P-700 photo-oxidation showed that the intersystem electron pool size was 1.4 times greater in JAS-H leaves than in PAO-H leaves. Furthermore, the re-reduction kinetics of P-700(+) showed that cyclic electron transport around PS I was 1.2 times faster in PAO-H leaves than in JAS-H leaves. Analysis of the area over the fluorescence induction kinetics indicated that the relative abundance of the PS IIalpha center increased in PAO-H leaves, whereas JAS leaves were observed to have low acclimation capacity to high light. These results demonstrate that PAO leaves possess acclimation mechanisms to continuous high light, whereas JAS leaves are more vulnerable to continuous high light, resulting in reduced leaf longevity owing to photoinhibition caused by increases in the intersystem electron pool size and suppression of photochemistry at the level of PS I and PS II. PMID:17403648

Yamazaki, Jun-Ya; Yoda, Etsuko; Takahashi, Ayako; Sonoike, Kintake; Maruta, Emiko

2007-07-01

152

Use of thermal imaging to determine leaf conductance along a canopy gradient in European beech (Fagus sylvatica).  

PubMed

Using an infrared camera, we measured the leaf temperature across different canopy positions of a 23-m-tall deciduous forest tree (Fagus sylvatica L.) including typical sun and shade leaves as well as intermediate leaf forms, which differed significantly in specific leaf area (SLA). We calculated a temperature index (I(G)) and a crop water stress index (CWSI) using the surface temperatures of wet and dry reference leaves. Additional indices were computed using air temperature plus 5 C (I(G)?+?5, CWSI?+?5) as dry references. The minimum temperature of the wet leaf and the maximum temperature of the dry leaf proved to be most suitable as reference values. We correlated the temperature indices with leaf area-related conductance to water vapor (g(L)) using porometry at the leaf level and using xylem sap flow at the branch level. At the leaf and at the branch level, I(G) and CWSI were equally well suited as proxies of g(L), whereas the relationships of I(G)?+?5 and CWSI?+?5 with g(L) were only weak or even insignificant. At the leaf level, the correlations of I(G) and CWSI with g(L) were significant in all parts of the crown. The slopes of g(L) vs. I(G) and CWSI did not differ significantly among the crown parts; this indicates that they were not influenced by SLA or irradiance. At the branch level, close correlations (r?>?0.8) were found between temperature indices and g(L) across the crown. These results demonstrate that satisfactory relationships between temperature indices and g(L) can be established in tall trees even in those canopy parts that are exposed to relatively low levels of irradiance and exhibit relatively low values of g(L). PMID:22427372

Reinert, Stefan; Bgelein, Rebekka; Thomas, Frank M

2012-03-01

153

Xanthomonas citri subsp. citri type IV Pilus is required for twitching motility, biofilm development, and adherence.  

PubMed

Bacterial type IV pili (T4P) are long, flexible surface filaments that consist of helical polymers of mostly pilin subunits. Cycles of polymerization, attachment, and depolymerization mediate several pilus-dependent bacterial behaviors, including twitching motility, surface adhesion, pathogenicity, natural transformation, escape from immune system defense mechanisms, and biofilm formation. The Xanthomonas citri subsp. citri strain 306 genome codes for a large set of genes involved in T4P biogenesis and regulation and includes several pilin homologs. We show that X. citri subsp. citri can exhibit twitching motility in a manner similar to that observed in other bacteria such as Pseudomonas aeruginosa and Xylella fastidiosa and that this motility is abolished in Xanthomonas citri subsp. citri knockout strains in the genes coding for the major pilin subunit PilAXAC3241, the ATPases PilBXAC3239 and PilTXAC2924, and the T4P biogenesis regulators PilZXAC1133 and FimXXAC2398. Microscopy analyses were performed to compare patterns of bacterial migration in the wild-type and knockout strains and we observed that the formation of mushroom-like structures in X. citri subsp. citri biofilm requires a functional T4P. Finally, infection of X. citri subsp. citri cells by the bacteriophage (?Xacm4-11 is T4P dependent. The results of this study improve our understanding of how T4P influence Xanthomonas motility, biofilm formation, and susceptibility to phage infection. PMID:25180689

Dunger, German; Guzzo, Cristiane R; Andrade, Maxuel O; Jones, Jeffrey B; Farah, Chuck S

2014-10-01

154

Infection with Mycobacterium avium subsp. paratuberculosis Results in Rapid Interleukin-1? Release and Macrophage Transepithelial Migration  

PubMed Central

Pathogen processing by the intestinal epithelium involves a dynamic innate immune response initiated by pathogen-epithelial cell cross talk. Interactions between epithelium and Mycobacterium avium subsp. paratuberculosis have not been intensively studied, and it is currently unknown how the bacterium-epithelial cell cross talk contributes to the course of infection. We hypothesized that M. avium subsp. paratuberculosis harnesses host responses to recruit macrophages to the site of infection to ensure its survival and dissemination. We investigated macrophage recruitment in response to M. avium subsp. paratuberculosis using a MAC-T bovine macrophage coculture system. We show that M. avium subsp. paratuberculosis infection led to phagosome acidification within bovine epithelial (MAC-T) cells as early as 10 min, which resulted in upregulation of interleukin-1? (IL-1?) at transcript and protein levels. Within 10 min of infection, macrophages were recruited to the apical side of MAC-T cells. Inhibition of phagosome acidification or IL-1? abrogated this response, while MCP-1/CCL-2 blocking had no effect. IL-1? processing was dependent upon Ca2+ uptake from the extracellular medium and intracellular Ca2+ oscillations, as determined by EGTA and BAPTA-AM [1,2-bis(2-aminophenoxy) ethane-N,N,N?,N?-tetraacetic acid tetrakis (acetoxymethyl ester)] treatments. Thus, M. avium subsp. paratuberculosis is an opportunist that takes advantage of extracellular Ca2+-dependent phagosome acidification and IL-1? processing in order to efficiently transverse the epithelium and enter its nichethe macrophage. PMID:22778093

Lamont, Elise A.; O'Grady, Scott M.; Davis, William C.; Eckstein, Torsten

2012-01-01

155

Spatial analysis of Yersinia pestis and Bartonella vinsonii subsp. berkhoffii seroprevalence in California coyotes (Canis latrans).  

PubMed

Zoonotic transmission of sylvatic plague caused by Yersinia pestis occurs in California, USA. Human infections with various Bartonella species have been reported recently. Coyotes (Canis latrans) are ubiquitous throughout California and can become infected with both bacterial agents, making the species useful for surveillance purposes. This study examined the geographic distribution of 863 coyotes tested for Y. pestis and Bartonella vinsonii subsp. berkhoffii serologic status to gain insight into the natural history of B. vinsonii subsp. berkhoffii and to characterize the spatial distribution of the two agents. We found 11.7% of specimens positive to Y. pestis and 35.5% positive to B. vinsonii subsp. berkhoffii. The two pathogens had distinct spatial clusters: Y. pestis was more prevalent in eastern portions of the state and B. vinsonii subsp. berkhoffii in coastal regions. Prevalence of Y. pestis increased with increasing elevation, whereas prevalence of B. vinsonii subsp. berkhoffii decreased with increasing elevation. There were differences in the proportions of positive animals on a yearly basis to both pathogens. PMID:12507856

Hoar, B R; Chomel, B B; Rolfe, D L; Chang, C C; Fritz, C L; Sacks, B N; Carpenter, T E

2003-01-15

156

Persistence of Bacillus thuringiensis subsp. kurstaki in Urban Environments following Spraying?  

PubMed Central

Bacillus thuringiensis subsp. kurstaki is applied extensively in North America to control the gypsy moth, Lymantria dispar. Since B. thuringiensis subsp. kurstaki shares many physical and biological properties with Bacillus anthracis, it is a reasonable surrogate for biodefense studies. A key question in biodefense is how long a biothreat agent will persist in the environment. There is some information in the literature on the persistence of Bacillus anthracis in laboratories and historical testing areas and for Bacillus thuringiensis in agricultural settings, but there is no information on the persistence of Bacillus spp. in the type of environment that would be encountered in a city or on a military installation. Since it is not feasible to release B. anthracis in a developed area, the controlled release of B. thuringiensis subsp. kurstaki for pest control was used to gain insight into the potential persistence of Bacillus spp. in outdoor urban environments. Persistence was evaluated in two locations: Fairfax County, VA, and Seattle, WA. Environmental samples were collected from multiple matrices and evaluated for the presence of viable B. thuringiensis subsp. kurstaki at times ranging from less than 1 day to 4 years after spraying. Real-time PCR and culture were used for analysis. B. thuringiensis subsp. kurstaki was found to persist in urban environments for at least 4 years. It was most frequently detected in soils and less frequently detected in wipes, grass, foliage, and water. The collective results indicate that certain species of Bacillus may persist for years following their dispersal in urban environments. PMID:21926205

Van Cuyk, Sheila; Deshpande, Alina; Hollander, Attelia; Duval, Nathan; Ticknor, Lawrence; Layshock, Julie; Gallegos-Graves, LaVerne; Omberg, Kristin M.

2011-01-01

157

Fate of Mycobacterium avium subsp. paratuberculosis in Swiss Hard and Semihard Cheese Manufactured from Raw Milk  

PubMed Central

Raw milk was artificially contaminated with declumped cells of Mycobacterium avium subsp. paratuberculosis at a concentration of 104 to 105 CFU/ml and was used to manufacture model hard (Swiss Emmentaler) and semihard (Swiss Tisliter) cheese. Two different strains of M. avium subsp. paratuberculosis were tested, and for each strain, two model hard and semihard cheeses were produced. The survival of M. avium subsp. paratuberculosis cells was monitored over a ripening period of 120 days by plating out homogenized cheese samples onto 7H10-PANTA agar. In both the hard and the semihard cheeses, counts decreased steadily but slowly during cheese ripening. Nevertheless, viable cells could still be detected in 120-day cheese. D values were calculated at 27.8 days for hard and 45.5 days for semihard cheese. The most important factors responsible for the death of M. avium subsp. paratuberculosis in cheese were the temperatures applied during cheese manufacture and the low pH at the early stages of cheese ripening. Since the ripening period for these raw milk cheeses lasts at least 90 to 120 days, the D values found indicate that 103 to 104 cells of M. avium subsp. paratuberculosis per g will be inactivated. PMID:11526024

Spahr, U.; Schafroth, K.

2001-01-01

158

Isolation of halotolerant Lactococcus lactis subsp. lactis from intestinal tract of coastal fish.  

PubMed

We isolated lactic acid bacteria from the intestinal tract of the pufferfish Takifugu niphobles caught in Shimoda, Shizuoka, Japan by using MRS broth prepared with 50% seawater. Additional screening was carried out using phenotypic tests such as Gram staining, cell morphology, catalase, oxidase and fermentation of glucose. Subsequently 227 isolates screened by the phenotypic tests were subjected to species-specific PCR for Lactococcus lactis, resulting in four positive isolates. The 16S rRNA gene sequences from three isolates were highly similar to that of L. lactis subsp. lactis (DNA database accession number M58837), while that of one isolate was identical to that of Leuconostoc mesenteroides (AB023246). These isolates were characterized by API 50 CH for carbohydrate fermentation and other phenotypic criteria for salt tolerance, and the characteristics were compared with those of L. lactis subsp. lactis from a cheese starter culture. The carbohydrate fermentation profiles of these isolates were characteristic of L. lactis subsp. lactis strains, whereas the tolerance of these isolates to salt was higher than that of L. lactis subsp. lactis from the cheese starter culture: the new L. lactis isolates showed high salt tolerance in MRS-agar plates containing 200% seawater or 6% sodium chloride. This is the first report of the isolation of halotolerant strains of L. lactis subsp. lactis from a marine environment. PMID:18068256

Itoi, Shiro; Abe, Takeshi; Washio, Sayaka; Ikuno, Erika; Kanomata, Yuna; Sugita, Haruo

2008-01-15

159

Estimation of Mycobacterium avium subsp. paratuberculosis Growth Parameters: Strain Characterization and Comparison of Methods?  

PubMed Central

The growth rate of Mycobacterium avium subsp. paratuberculosis was assessed by different methods in 7H9 medium supplemented with OADC (oleic acid, albumin, dextrose, catalase), Tween 80, and mycobactin J. Generation times and maximum specific growth rates were determined by wet weight, turbidometric measurement, viable count, and quantitative PCR (ParaTB-Kuanti; F57 gene) for 8 M. avium subsp. paratuberculosis strains (K10, 2E, 316F, 81, 445, 764, 22G, and OVICAP 49). Strain-to-strain differences were observed in growth curves and calculated parameters. The quantification methods gave different results for each strain at specific time points. Generation times ranged from an average of 1.4 days for viable count and qPCR to approximately 10 days for wet weight and turbidometry. The wet-weight, turbidometry, and ParaTB-Kuanti qPCR methods correlated best with each other. Generally, viability has been assessed by viable count as a reference method; however, due to M. avium subsp. paratuberculosis clumping problems and the presence of noncultivable M. avium subsp. paratuberculosis cells, we conclude that qPCR of a single-copy gene may be used reliably for rapid estimation of M. avium subsp. paratuberculosis bacterial numbers in a sample. PMID:22003015

Elguezabal, Natalia; Bastida, Felix; Sevilla, Iker A.; Gonzalez, Nuria; Molina, Elena; Garrido, Joseba M.; Juste, Ramon A.

2011-01-01

160

Detection and Verification of Mycobacterium avium subsp. paratuberculosis in Fresh Ileocolonic Mucosal Biopsy Specimens from Individuals with and without Crohn's Disease  

Microsoft Academic Search

Mycobacterium avium subsp. paratuberculosis is a robust and phenotypically versatile pathogen which causes chronic inflammation of the intestine in many species, including primates. M. avium subsp. paratuberculosis infection is widespread in domestic livestock and is present in retail pasteurized cows' milk in the United Kingdom and, potentially, elsewhere. Water supplies are also at risk. The involvement of M. avium subsp.

Tim J. Bull; Elizabeth J. McMinn; Karim Sidi-Boumedine; Angela Skull; Damien Durkin; Penny Neild; Glenn Rhodes; Roger Pickup; John Hermon-Taylor

2003-01-01

161

Distribution of Bacillus thuringiensis subsp. israelensis in Soil of a Swiss Wetland Reserve after 22 Years of Mosquito Control?  

PubMed Central

Recurrent treatments with Bacillus thuringiensis subsp. israelensis are required to control the floodwater mosquito Aedes vexans that breeds in large numbers in the wetlands of the Bolle di Magadino Reserve in Canton Ticino, Switzerland. Interventions have been carried out since 1988. In the present study, the spatial distribution of resting B. thuringiensis subsp. israelensis spores in the soil was measured. The B. thuringiensis subsp. israelensis concentration was determined in soil samples collected along six transects covering different elevations within the periodically flooded zones. A total of 258 samples were processed and analyzed by quantitative PCR that targeted an identical fragment of 159 bp for the B. thuringiensis subsp. israelensis cry4Aa and cry4Ba genes. B. thuringiensis subsp. israelensis spores were found to persist in soils of the wetland reserve at concentrations of up to 6.8 log per gram of soil. Continuous accumulation due to regular treatments could be excluded, as the decrease in spores amounted to 95.8% (95% confidence interval, 93.9 to 97.7%). The distribution of spores was correlated to the number of B. thuringiensis subsp. israelensis treatments, the elevation of the sampling point, and the duration of the flooding periods. The number of B. thuringiensis subsp. israelensis treatments was the major factor influencing the distribution of spores in the different topographic zones (P < 0.0001). These findings indicated that B. thuringiensis subsp. israelensis spores are rather immobile after their introduction into the environment. PMID:21498758

Guidi, Valeria; Patocchi, Nicola; Lthy, Peter; Tonolla, Mauro

2011-01-01

162

The genome of Aeromonas salmonicida subsp. salmonicida A449: insights into the evolution of a fish pathogen  

Microsoft Academic Search

BACKGROUND: Aeromonas salmonicida subsp. salmonicida is a Gram-negative bacterium that is the causative agent of furunculosis, a bacterial septicaemia of salmonid fish. While other species of Aeromonas are opportunistic pathogens or are found in commensal or symbiotic relationships with animal hosts, A. salmonicida subsp. salmonicida causes disease in healthy fish. The genome sequence of A. salmonicida was determined to provide

Michael E Reith; Rama K Singh; Bruce Curtis; Jessica M Boyd; Anne Bouevitch; Jennifer Kimball; Janet Munholland; Colleen Murphy; Darren Sarty; Jason Williams; John HE Nash; Stewart C Johnson; Laura L Brown

2008-01-01

163

The effectiveness of plant essential oils on the growth of Botrytis cinerea, Fusarium sp. and Clavibacter michiganensis subsp. michiganensis  

Microsoft Academic Search

Oregano, thyme, dictamnus, marjoram, lavender, rosemary, sage and pennyroyal essential oils were tested for their effectiveness against Botrytis cinerea, Fusarium sp. (Fusarium solani var. coeruleum), and Clavibacter michiganensis subsp. michiganensis on artificial growth media. The chemical composition of the oils was determined by gas chromatography-mass spectrometry (GC-MS). The growth of Botrytis cinerea, Fusarium sp. and Clavibacter michiganensis subsp. michiganensis was

Dimitra J Daferera; Basil N Ziogas; Moschos G Polissiou

2003-01-01

164

Draft Genome Sequences of Campylobacter fetus subsp. venerealis bv. venerealis Strain B6 and bv. intermedius Strain 642-21.  

PubMed

Campylobacter fetus subsp. venerealis is an important venereal pathogen. We sequenced the genomes of Campylobacter fetus subsp. venerealis bv. venerealis strain B6 and bv. intermedius strain 642-21. The genetic variability of these Australian strains will facilitate the study of mechanisms of geographical adaptation of these pathogens that impact livestock. PMID:25278524

Barrero, Roberto A; Moolhuijzen, Paula; Indjein, La; Venus, Bronwyn; Keeble-Gagnre, Gabriel; Power, John; Bellgard, Matthew I; Lew-Tabor, Ala E

2014-01-01

165

Complete Genome Sequence of Leifsonia xyli subsp. cynodontis Strain DSM46306, a Gram-Positive Bacterial Pathogen of Grasses  

PubMed Central

We announce the complete genome sequence of Leifsonia xyli subsp. cynodontis, a vascular pathogen of Bermuda grass. The species also comprises Leifsonia xyli subsp. xyli, a sugarcane pathogen. Since these two subspecies have genome sequences available, a comparative analysis will contribute to our understanding of the differences in their biology and host specificity. PMID:24201198

Zerillo, Marcelo Marques; Van Sluys, Marie-Anne; Camargo, Luis Eduardo Aranha; Kitajima, Joao Paulo

2013-01-01

166

Copper tolerance in the macrolichens Cladonia furcata and Cladina arbuscula subsp. mitis is constitutive rather than inducible  

Microsoft Academic Search

In this study we assessed the degree of copper (Cu) tolerance in two common lichen species (Cladonia furcata and Cladina arbuscula subsp. mitis) that grow on both uncontaminated substrata and the surface of waste heaps from abandoned old Cu-mines. Regardless of their locality, populations of these lichens contain identical strains of photobionts (Asterochloris clade A in C. arbuscula subsp. mitis

Martin Ba?kor; Evelin Ramna Pli; Ivana Vantov

2011-01-01

167

Draft Genome Sequences of Campylobacter fetus subsp. venerealis bv. venerealis Strain B6 and bv. intermedius Strain 642-21  

PubMed Central

Campylobacter fetus subsp. venerealis is an important venereal pathogen. We sequenced the genomes of Campylobacter fetus subsp. venerealis bv. venerealis strain B6 and bv. intermedius strain 642-21. The genetic variability of these Australian strains will facilitate the study of mechanisms of geographical adaptation of these pathogens that impact livestock. PMID:25278524

Barrero, Roberto A.; Moolhuijzen, Paula; Indjein, Lea; Venus, Bronwyn; Keeble-Gagnere, Gabriel; Power, John

2014-01-01

168

Culture and Serologic Survey for Mycobacterium avium subsp. paratuberculosis Infection among Southeastern White-tailed Deer (Odocoileus virginianus)  

Microsoft Academic Search

From July 1998 through October 2002, radiometric culture (ileocecal lymph node, mesenteric lymph node, and feces) and serologic testing by enzyme-linked immunosor- bent assay (ELISA) were used to survey white- tailed deer (Odocoileus virginianus) from the southeastern United States for infection by My- cobacterium avium subsp. paratuberculosis (Mptb), the causative agent of paratuberculosis (Johne's disease). Mycobacterium avium subsp. paratuberculosis was

William R. Davidson; Elizabeth J. B. Manning; Victor F. Nettles; D. B. Warnell

169

Comparative Phenotypic and Molecular Genetic Profiling of Wild Lactococcus lactis subsp. lactis Strains of the L. lactis subsp. lactis and L. lactis subsp. cremoris Genotypes, Isolated from Starter-Free Cheeses Made of Raw Milk?  

PubMed Central

Twenty Lactococcus lactis strains with an L. lactis subsp. lactis phenotype isolated from five traditional cheeses made of raw milk with no added starters belonging to the L. lactis subsp. lactis and L. lactis subsp. cremoris genotypes (lactis and cremoris genotypes, respectively; 10 strains each) were subjected to a series of phenotypic and genetic typing methods, with the aims of determining their phylogenetic relationships and suitability as starters. Pulsed-field gel electrophoresis (PFGE) analysis of intact genomes digested with SalI and SmaI proved that all strains were different except for three isolates of the cremoris genotype, which showed identical PFGE profiles. Multilocus sequence typing (MLST) analysis using internal sequences of seven loci (namely, atpA, rpoA, pheS, pepN, bcaT, pepX, and 16S rRNA gene) revealed considerable intergenotype nucleotide polymorphism, although deduced amino acid changes were scarce. Analysis of the MLST data for the present strains and others from other dairy and nondairy sources showed that all of them clustered into the cremoris or lactis genotype group, by using both independent and combined gene sequences. These two groups of strains also showed distinctive carbohydrate fermentation and enzyme activity profiles, with the strains in the cremoris group showing broader profiles. However, the profiles of resistance/susceptibility to 16 antibiotics were very similar, showing no atypical resistance, except for tetracycline resistance in three identical cremoris genotype isolates. The numbers and concentrations of volatile compounds produced in milk by the strains belonging to these two groups were clearly different, with the cremoris genotype strains producing higher concentrations of more branched-chain, derived compounds. Together, the present results support the idea that the lactis and cremoris genotypes of phenotypic Lactococcus lactis subsp. lactis actually represent true subspecies. Some strains of the two subspecies in this study appear to be good starter candidates. PMID:21666023

Fernandez, Elena; Alegria, Angel; Delgado, Susana; Martin, M. Cruz; Mayo, Baltasar

2011-01-01

170

Complete Genome Sequences of Virulent Mycoplasma capricolum subsp. capripneumoniae Strains F38 and ILRI181  

PubMed Central

Contagious caprine pleuropneumonia (CCPP) caused by Mycoplasma capricolum subsp. capripneumoniae is a severe epidemic affecting mainly domestic Caprinae species but also affects wild Caprinae species. M. capricolum subsp. capripneumoniae belongs to the Mycoplasma mycoides cluster. The disease features prominently in East Africa, in particular Kenya, Tanzania, and Ethiopia. CCPP also endangers wildlife and thus affects not only basic nutritional resources of large populations but also expensively built-up game resorts in affected countries. Here, we report the complete sequences of two M. capricolum subsp. capripneumoniae strains: the type strain F38 and strain ILRI181 isolated druing a recent outbreak in Kenya. Both genomes have a G+C content of 24% with sizes of 1,016,760bp and 1,017,183bp for strains F38 and ILRI181, respectively. PMID:25323717

Liljander, Anne; Schieck, Elise; Gluecks, Ilona; Frey, Joachim; Jores, Joerg

2014-01-01

171

Complete Genome Sequences of Virulent Mycoplasma capricolum subsp. capripneumoniae Strains F38 and ILRI181.  

PubMed

Contagious caprine pleuropneumonia (CCPP) caused by Mycoplasma capricolum subsp. capripneumoniae is a severe epidemic affecting mainly domestic Caprinae species but also affects wild Caprinae species. M. capricolum subsp. capripneumoniae belongs to the "Mycoplasma mycoides cluster." The disease features prominently in East Africa, in particular Kenya, Tanzania, and Ethiopia. CCPP also endangers wildlife and thus affects not only basic nutritional resources of large populations but also expensively built-up game resorts in affected countries. Here, we report the complete sequences of two M. capricolum subsp. capripneumoniae strains: the type strain F38 and strain ILRI181 isolated druing a recent outbreak in Kenya. Both genomes have a G+C content of 24% with sizes of 1,016,760bp and 1,017,183bp for strains F38 and ILRI181, respectively. PMID:25323717

Falquet, Laurent; Liljander, Anne; Schieck, Elise; Gluecks, Ilona; Frey, Joachim; Jores, Joerg

2014-01-01

172

Aeromonas hydrophila subsp. dhakensis Isolated from Feces, Water and Fish in Mediterranean Spain  

PubMed Central

Eight Aeromonas hydrophila-like arabinose-negative isolates from diverse sources (i.e., river freshwater, cooling-system water pond, diseased wild European eels, and human stools) sampled in Valencia (Spain) during 20042005, were characterized by 16S rRNA gene sequencing and extensive biochemical testing along with reference strains of most Aeromonas species. These isolates and all reference strains of A. hydrophila subsp. dhakensis and A. aquariorum showed a 16S rRNA sequence similarity of 99.8100%, and they all shared an identical phenotype. This matched exactly with that of A. hydrophila subsp. dhakensis since all strains displayed positive responses to the Voges-Prokauer test and to the use of dl-lactate. This is the first report of A. hydrophila subsp. dhakensis recovered from environmental samples, and further, from its original isolation in India during 19931994. This was accurately identified and segregated from other clinical aeromonads (A. hydrophila subsp. hydrophila, A. caviae, A. veronii biovars veronii and sobria, A. trota, A. schubertii and A. jandaei) by using biochemical key tests. The API 20 E profile for all strains included in A. hydrophila subsp. dhakensis was 7047125. The prevalence of this species in Spanish sources was higher for water (9.4%) than for feces (6%) or eels (1.3%). Isolates recovered as pure cultures from diseased eels were moderately virulent (LD50 of 3.3106 CFU fish?1) to challenged eels in experimental trials. They were all resistant to ticarcillin, amoxicillin-clavuranic acid, cefoxitin, and imipenem, regardless of its source. Our data point to A. hydrophila subsp. dhakensis as an emerging pathogen for humans and fish in temperate countries. PMID:22472298

Esteve, Consuelo; Alcaide, Elena; Blasco, Maria Dolores

2012-01-01

173

Oral immunoadjuvant activity of Lactobacillus casei subsp. casei in dextran-fed layer chickens.  

PubMed

We recently reported that synbiotic Lactobacillus casei subsp. casei together with specific substrate dextran elicited an enhancement in humoral immune response against bovine serum albumin (BSA) as a model antigen in BALB/c mice. The present study was designed to evaluate the oral immunoadjuvant effects of the synbiotic in layer chickens. Using a PCR assay, L. casei subsp. casei was detected specifically in the intestinal chyme of chickens (10 d of age, Julia strain) fed ad libitum on a diet supplemented with 75 mg dextran/kg (dextran-supplemented diet, DSD) and administered orally with 10(7) colony-forming units (CFU) L. casei subsp. casei in 0.1 ml PBS with the aid of an intubation needle at 1, 2 and 3 d of age. Furthermore, oral administration of 10(7) CFU L. casei subsp. casei at 1-3 d of age significantly enhanced the production of anti-BSA antibody in DSD-fed chickens (60 d of age) administered orally with 1 mg BSA at 32 and 33 d of age and subcutaneously with 5 microg BSA at 33 d of age. In addition, among bacterial numbers tested, 10(6) CFU L. casei subsp. casei together with dextran induced an effective increase in humoral immune response to mixed inactivated vaccines against Newcastle disease and avian infectious bronchitis, and the treatment may be advantageous in protecting against these infectious diseases in chickens in actual application. These results suggest that dietary supplementation of L. casei subsp. casei with dextran leads to immunomodulation of humoral immune responses. PMID:16469163

Ogawa, Tomohiko; Asai, Yasuyuki; Sakamoto, Hiromi; Yasuda, Kenji

2006-02-01

174

Persistence and recycling of bioinsecticidal Bacillus thuringiensis subsp. israelensis spores in contrasting environments: evidence from field monitoring and laboratory experiments.  

PubMed

Sprays of commercial preparations of the bacterium Bacillus thuringiensis subsp. israelensis are widely used for the control of mosquito larvae. Despite an abundant literature on B. thuringiensis subsp. israelensis field efficiency on mosquito control, few studies have evaluated the fate of spores in the environment after treatments. In the present article, two complementary experiments were conducted to study the effect of different parameters on B. thuringiensis subsp. israelensis persistence and recycling, in field conditions and in the laboratory. First, we monitored B. thuringiensis subsp. israelensis persistence in the field in two contrasting regions in France: the Rhne-Alpes region, where mosquito breeding sites are temporary ponds under forest cover with large amounts of decaying leaf matter on the ground and the Mediterranean region characterized by open breeding sites such as brackish marshes. Viable B. thuringiensis subsp. israelensis spores can persist for months after a treatment, and their quantity is explained both by the vegetation type and by the number of local treatments. We found no evidence of B. thuringiensis subsp. israelensis recycling in the field. Then, we tested the effect of water level, substrate type, salinity and presence of mosquito larvae on the persistence/recycling of B. thuringiensis subsp. israelensis spores in controlled laboratory conditions (microcosms). We found no effect of change in water level or salinity on B. thuringiensis subsp. israelensis persistence over time (75 days). B. thuringiensis subsp. israelensis spores tended to persist longer in substrates containing organic matter compared to sand-only substrates. B. thuringiensis subsp. israelensis recycling only occurred in presence of mosquito larvae but was unrelated to the presence of organic matter. PMID:24402370

Duchet, Claire; Tetreau, Guillaume; Marie, Albane; Rey, Delphine; Besnard, Gilles; Perrin, Yvon; Paris, Margot; David, Jean-Philippe; Lagneau, Christophe; Desprs, Laurence

2014-04-01

175

Characterization of Free Exopolysaccharides Secreted by Mycoplasma mycoides Subsp. mycoides  

PubMed Central

Contagious bovine pleuropneumonia is a severe respiratory disease of cattle that is caused by a bacterium of the Mycoplasma genus, namely Mycoplasma mycoides subsp. mycoides (Mmm). In the absence of classical virulence determinants, the pathogenicity of Mmm is thought to rely on intrinsic metabolic functions and specific components of the outer cell surface. One of these latter, the capsular polysaccharide galactan has been notably demonstrated to play a role in Mmm persistence and dissemination. The free exopolysaccharides (EPS), also produced by Mmm and shown to circulate in the blood stream of infected cattle, have received little attention so far. Indeed, their characterization has been hindered by the presence of polysaccharide contaminants in the complex mycoplasma culture medium. In this study, we developed a method to produce large quantities of EPS by transfer of mycoplasma cells from their complex broth to a chemically defined medium and subsequent purification. NMR analyses revealed that the purified, free EPS had an identical ?(1?>6)-galactofuranosyl structure to that of capsular galactan. We then analyzed intraclonal Mmm variants that produce opaque/translucent colonies on agar. First, we demonstrated that colony opacity was related to the production of a capsule, as observed by electron microscopy. We then compared the EPS extracts and showed that the non-capsulated, translucent colony variants produced higher amounts of free EPS than the capsulated, opaque colony variants. This phenotypic variation was associated with an antigenic variation of a specific glucose phosphotransferase permease. Finally, we conducted in silico analyses of candidate polysaccharide biosynthetic pathways in order to decipher the potential link between glucose phosphotransferase permease activity and attachment/release of galactan. The co-existence of variants producing alternative forms of galactan (capsular versus free extracellular galactan) and associated with an antigenic switch constitutes a finely tuned mechanism that may be involved in virulence. PMID:23869216

Bertin, Clothilde; Pau-Roblot, Corinne; Courtois, Josiane; Manso-Silvn, Luca; Thiaucourt, Franois; Tardy, Florence; Le Grand, Dominique; Poumarat, Franois; Gaurivaud, Patrice

2013-01-01

176

Reproductive biology of the andromonoecious Cucumis melo subsp. agrestis (Cucurbitaceae)  

PubMed Central

Background and Aims Cucumis melo subsp. agrestis (Cucurbitaceae) is cultivated in many African regions for its edible kernels used as a soup thickener. The plant, an annual, andromonoecious, trailing-vine species, is of high social, cultural and economic value for local communities. In order to improve the yield of this crop, the first step and our aim were to elucidate its breeding system. Methods Eight experimental pollination treatments were performed during three growing seasons to assess spontaneous selfing, self-compatibility and effects of pollen source (hermaphroditic vs. male flowers). Pollination success was determined by pollen tube growth and reproductive success was assessed by fruit, seed and seedling numbers and characteristics. The pollinator guild was surveyed and the pollination distance determined both by direct observations and by indirect fluorescent dye dispersal. Key Results The species is probably pollinated by several Hymenoptera, principally by Hypotrigona para. Pollinator flight distances varied from 25 to 69 cm. No evidence for apomixis or spontaneous self-pollination in the absence of insect visitors was found. The self-fertility index (SFI = 0) indicated a total dependence on pollinators for reproductive success. The effects of hand pollination on fruit set, seed number and seedling fitness differed among years. Pollen tube growth and reproductive success did not differ between self- and cross-pollinations. Accordingly, a high self-compatibility index for the fruit set (SCI = 100) and the seed number (SCI = 098) and a low inbreeding depression at all developmental stages (cumulative ? = 0126) suggest a high selfing ability. Finally, pollen origin had no effect on fruit and seed sets. Conclusions This andromonoecious species has the potential for a mixed mating system with high dependence on insect-mediated pollination. The selfing rate through geitonogamy should be important. PMID:19671577

Kouonon, Leonie C.; Jacquemart, Anne-Laure; Zoro Bi, Arsene I.; Bertin, Pierre; Baudoin, Jean-Pierre; Dje, Yao

2009-01-01

177

Tree-Ring Stable Isotopes Reveal Twentieth-Century Increases in Water-Use Efficiency of Fagus sylvatica and Nothofagus spp. in Italian and Chilean Mountains  

PubMed Central

Changes in intrinsic water use efficiency (iWUE) were investigated in Fagus sylvatica and Nothofagus spp. over the last century. We combined dendrochronological methods with dual-isotope analysis to investigate whether atmospheric changes enhanced iWUE of Fagus and Nothofagus and tree growth (basal area increment, BAI) along latitudinal gradients in Italy and Chile. Post-maturation phases of the trees presented different patterns in ?13C, ?13C, ?18O, Ci (internal CO2 concentration), iWUE, and BAI. A continuous enhancement in isotope-derived iWUE was observed throughout the twentieth century, which was common to all sites and related to changes in Ca (ambient CO2 concentration) and secondarily to increases in temperature. In contrast to other studies, we observed a general increasing trend of BAI, with the exception of F. sylvatica in Aspromonte. Both iWUE and BAI were uncoupled with the estimated drought index, which is in agreement with the absence of enduring decline in tree growth. In general, ?13C and ?18O showed a weak relationship, suggesting the major influence of photosynthetic rate on Ci and ?13C, and the minor contribution of the regulation of stomatal conductance to iWUE. The substantial warming observed during the twentieth century did not result in a clear pattern of increased drought stress along these latitudinal transects, because of the variability in temporal trends of precipitation and in specific responses of populations. PMID:25398040

Tognetti, Roberto; Lombardi, Fabio; Lasserre, Bruno; Cherubini, Paolo; Marchetti, Marco

2014-01-01

178

Seroepidemiology of Bartonella vinsonii subsp. berkhoffii infection in California coyotes, 1994-1998.  

PubMed

The prevalence of antibodies to Bartonella vinsonii subsp. berkhoffii in coyotes (Canis latrans) in California ranged from 51% in central to 34% in southern and 7% in northern California. Seropositive coyotes were more likely to be from coastal than inland counties (p clustered distribution of Bartonella seropositivity in coyotes suggests that B. vinsonii subsp. berkhoffii infection is vectorborne. Further investigation is warranted to evaluate which arthropods are vectors and what the mode of transmission is from wildlife to domestic dogs and possibly humans. PMID:10511529

Chang, C; Yamamoto, K; Chomel, B B; Kasten, R W; Simpson, D C; Smith, C R; Kramer, V L

1999-01-01

179

Essential oil composition of the fruits of Periploca laevigata Aiton subsp. angustifolia (Labill.) Markgraf (Apocynaceae - Periplocoideae).  

PubMed

The essential oil of the fruits of Periploca laevigata Aiton subsp. angustifolia (Labill.) Markgraf (Apocynaceae) from Lampedusa Island was obtained by hydrodistillation and its composition was analysed. The analyses allowed the identification and quantification of 64 volatile compounds belonging to different classes. The most abundant compounds were nonacosane, heptacosane, hentriacontane and ?-cadinene. Among the volatile compounds identified in the fruits of P. laevigata subsp. angustifolia, 31 are present in other taxa of Apocynaceae, 19 have antimicrobial activity and four are pheromones for the butterfly Danaus chrysippus. The possible ecological role of the volatile compounds found is briefly discussed. PMID:21859258

Zito, Pietro; Sajeva, Maurizio; Bruno, Maurizio; Maggio, Antonella; Rosselli, Sergio; Senatore, Felice; Formisano, Carmen

2011-08-01

180

Genome-Wide DNA Microarray Analysis of Francisella tularensis Strains Demonstrates Extensive Genetic Conservation within the Species but Identifies Regions That Are Unique to the Highly Virulent F. tularensis subsp. tularensis  

Microsoft Academic Search

Francisella tularensis is a potent pathogen and a possible bioterrorism agent. Little is known, however, to ex- plain the molecular basis for its virulence and the distinct differences in virulence found between the four rec- ognized subspecies, F. tularensis subsp. tularensis, F. tularensis subsp. mediasiatica, F. tularensis subsp. holarc- tica, and F. tularensis subsp. novicida. We developed a DNA microarray

Martien Broekhuijsen; Par Larsson; Anders Johansson; Mona Bystrom; Ulla Eriksson; Eva Larsson; Richard G. Prior; Anders Sjostedt; Richard W. Titball; Mats Forsman; TNO Prins

2003-01-01

181

Antioxidant Activity of the Essential Oils of Different Parts of Juniperus excelsa M. Bieb. subsp. excelsa and J. excelsa M. Bieb. subsp. polycarpos (K. Koch) Takhtajan (Cupressaceae)  

PubMed Central

The essential oils of branchlets and fruits of Juniperus excelsa subsp. excelsa and Juniperus excelsa subsp. polycarpos were examined for their antioxidant activity. The compositions of the essential oils were studied by GC and GC-MS. To evaluation the antioxidants activity of the volatile oils, pure components and positive controls at different concentrations, thin-layer chromatography (TLC) screening methods, diphenylpicrylhydrazyl (DPPH) assay, deoxyribose degradation test and modified deoxyribose degradation test were employed. The results of the present study demonstrate some antioxidant activity for the tested essential oils obtained from various parts of both plants. It indicates that the use of these essential oils, in very low concentrations, may be useful as a natural preservative. However before any final conclusion, it is suggested that the antioxidant activity of these oils should also be evaluated by using lipid solvent system methods. PMID:24250416

Emami, Sayyed Ahmad; Abedindo, Bibi Fatemeh; Hassanzadeh-Khayyat, Mohammad

2011-01-01

182

What are the functional mechanisms underlying forest decline? A case study on a European beech (Fagus sylvatica L.) stand.  

NASA Astrophysics Data System (ADS)

The ongoing climate change is altering the precipitation patterns (abundance and frequency) of most parts of the world. The consequences of these changes on forests are already visible through frequent declines. A lot of them can be linked to the occurrence of long and/or repeated drought periods. Although forest decline could severely impact the nutrient and water cycles, their underlying functional causes are not well understood. Two main hypotheses have been proposed to explain the mechanisms of decline at the tree level: Carbon reserves deficit ("carbon starvation") Loss of water transport ( "hydraulic failure") Although hydraulic failure has been observed in a wetland species decline (poplar), our understanding of forest decline is still lacking in many species. Our study concerns a widespread species, European beech (Fagus sylvatica L.). A severely declining mature beech plot in the Fontainebleau state forest (France) was followed. This decline can be related to repeated droughts, enhanced by unfavorable soil conditions (sandy soil with very low extractible soil water). For the first time to our knowledge, an integrative in situ functional approach coupling both hydraulic and carbon, but also nitrogen functioning was developed. More precisely, pre-dawn and midday water potentials, "native" embolism, and embolism vulnerability of branches, radial tree growth, carbon and nitrogen reserves concentrations, were measured on healthy and declining trees. Our results showed that under normal climatic conditions (summer 2012), pre-dawn and midday water potentials were the same for healthy and declining trees throughout the season. Their losses of hydraulic conductivity ("native" embolism) were not significantly different, even at the end of the summer. Moreover, the embolism vulnerability curves also showed no significant difference (50% loss of hydraulic conductivity at around - 3MPa). Concerning C and N reserves concentrations, we showed that seasonal variations were the same for healthy and declining trees. However, starch concentration was significantly lower before budburst in 2010 growth units and recent xylem rings in declining trees. These deficits in short distance storage compartments could lead to an altered spring growth. Indeed, radial growth rate and duration were drastically lower for declining trees. Finally, the observed beech decline cannot be attributed to either hydraulic dysfunction or nitrogen starvation. Concerning carbon functioning, the carbon reserves of declining trees were far from being exhausted. Despite a lower net carbon assimilation at the tree level (reduced leaf area index), trees maintain similar carbon and nitrogen reserves content, radial growth being apparently the adjusted variable.

Delaporte, Alice; Bazot, Stphane; Fresneau, Chantal; Damesin, Claire

2013-04-01

183

Physical and genetic map of the Lactococcus lactis subsp. cremoris MG1363 chromosome: comparison with that of Lactococcus lactis subsp. lactis IL 1403 reveals a large genome inversion.  

PubMed Central

A physical and genetic map of the chromosome of the Lactococcus lactis subsp. cremoris reference strain MG1363 was established. The physical map was constructed for NotI, ApaI, and SmaI enzymes by using a strategy that combines creation of new rare restriction sites by the random-integration vector pRL1 and ordering of restriction fragments by indirect end-labeling experiments. The MG1363 chromosome appeared to be circular and 2,560 kb long. Seventy-seven chromosomal markers were located on the physical map by hybridization experiments. Integration via homologous recombination of pRC1-derived plasmids allowed a more precise location of some lactococcal genes and determination of their orientation on the chromosome. The MG1363 chromosome contains six rRNA operons; five are clustered within 15% of the chromosome and transcribed in the same direction. Comparison of the L. lactis subsp. cremoris MG1363 physical map with those of the two L. lactis subsp. lactis strains IL1403 and DL11 revealed a high degree of restriction polymorphism. At the genetic organization level, despite an overall conservation of gene organization, strain MG1363 presents a large inversion of half of the genome in the region containing the rRNA operons. PMID:7751295

Le Bourgeois, P; Lautier, M; van den Berghe, L; Gasson, M J; Ritzenthaler, P

1995-01-01

184

Multilocus sequence analysis of Vibrio tapetis, the causative agent of Brown Ring Disease: description of Vibrio tapetis subsp. britannicus subsp. nov.  

PubMed

Vibrio tapetis is the causative agent of an epizootic infection described in adult clams called Brown Ring Disease (BRD). The isolation of the pathogen from different hosts showed strain variability both at serological and genetic level, allowing the description of three major groups related to the host origin of the isolates. In this work we performed for the first time a phylogenetic study for this pathogen. When including the closest related Vibrio species, all strains of V. tapetis appeared as a robust monophyletic cluster in the trees generated from all genes studied, namely 16S rRNA, atpA, fstZ, gapA, pyrH, recA, rpoA and rpoD and topA, as well as from their concatenated sequences. On the other hand, V. tapetis strains appeared clearly separated in two main clusters, sharing a similarity percentage for the concatenated sequences from 95 to 95.2% and values of DDH between 65.5 and 79.8%. Both clusters are themselves variable, with isolates within each cluster grouped according their host origin. The two clusters are easily distinguishable for their capacity to produce acid from mannitol and arabinose and for the use of citrate. Therefore, the results obtained supported the existence of two subspecies within this pathogen for which the names V. tapetis subsp. tapetis and V. tapetis subsp. britannicus subsp. nov. are proposed. PMID:23394813

Balboa, Sabela; Romalde, Jess L

2013-05-01

185

Bioprocessing of some agro-industrial residues for endoglucanase production by the new subsp.; Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J  

PubMed Central

The use of low cost agro-industrial residues for the production of industrial enzymes is one of the ways to reduce significantly production costs. Cellulase producing actinomycetes were isolated from soil and decayed agricultural wastes. Among them, a potential culture, strain NEAE-J, was selected and identified on the basis of morphological, cultural, physiological and chemotaxonomic properties, together with 16S rDNA sequence. It is proposed that strain NEAE-J should be included in the species Streptomyces albogriseolus as a representative of a novel sub-species, Streptomyces albogriseolus subsp. cellulolyticus strain NEAE-J and sequencing product was deposited in the GenBank database under accession number JN229412. This organism was tested for its ability to produce endoglucanase and release reducing sugars from agro-industrial residues as substrates. Sugarcane bagasse was the most suitable substrate for endoglucanase production. Effects of process variables, namely incubation time, temperature, initial pH and nitrogen source on production of endoglucanase by submerged fermentation using Streptomyces albogriseolus subsp. cellulolyticus have been studied. Accordingly optimum conditions have been determined. Incubation temperature of 30 C after 6 days, pH of 6.5, 1% sugarcane bagasse as carbon source and peptone as nitrogen source were found to be the optimum for endoglucanase production. Optimization of the process parameters resulted in about 2.6 fold increase in the endoglucanase activity. Therefore, Streptomyces albogriseolus subsp. cellulolyticus coud be potential microorganism for the intended application.

El-Naggar, Noura El-Ahmady; Abdelwahed, Nayera A.M.; Saber, Wesam I.A.; Mohamed, Asem A.

2014-01-01

186

Clavibacter michiganensis subsp. michiganensis Vatr1 and Vatr2 transcriptional regulators are required for virulence in tomato.  

PubMed

The plant pathogen Clavibacter michiganensis subsp. michiganensis is a gram-positive bacterium responsible for wilt and canker disease of tomato. Although disease development is well characterized and diagnosed, molecular mechanisms of C. michiganensis subsp. michiganensis virulence are poorly understood. Here, we identified and characterized two C. michiganensis subsp. michiganensis transcriptional regulators, Vatr1 and Vatr2, that are involved in pathogenicity of C. michiganensis subsp. michiganensis. Vatr1 and Vatr2 belong to TetR and MocR families of transcriptional regulators, respectively. Mutations in their corresponding genes caused attenuated virulence, with the ?vatr2 mutant showing a more dramatic effect than ?vatr1. Although both mutants grew well in vitro and reached a high titer in planta, they caused reduced wilting and canker development in infected plants compared with the wild-type bacterium. They also led to a reduced expression of the ethylene-synthesizing tomato enzyme ACC-oxidase compared with wild-type C. michiganensis subsp. michiganensis and to reduced ethylene production in the plant. Transcriptomic analysis of wild-type C. michiganensis subsp. michiganensis and the two mutants under infection-mimicking conditions revealed that Vatr1 and Vatr2 regulate expression of virulence factors, membrane and secreted proteins, and signal-transducing proteins. A 70% overlap between the sets of genes positively regulated by Vatr1 and Vatr2 suggests that these transcriptional regulators are on the same molecular pathway responsible for C. michiganensis subsp. michiganensis virulence. PMID:24940988

Savidor, Alon; Chalupowicz, Laura; Teper, Doron; Gartemann, Karl-Heinz; Eichenlaub, Rudolf; Manulis-Sasson, Shulamit; Barash, Isaac; Sessa, Guido

2014-10-01

187

Whole-Genome Sequencing of Salmonella enterica subsp. enterica Serovar Cubana Strains Isolated from Agricultural Sources.  

PubMed

We report the draft genomes of Salmonella enterica subsp. enterica serovar Cubana strain CVM42234, isolated from chick feed in 2012, and S. Cubana strain 76814, isolated from swine in 2004. The genome sizes are 4,975,046 and 4,936,251bp, respectively. PMID:24459266

Benahmed, Faiza H; Gopinath, Gopal R; Wang, Hua; Jean-Gilles Beaubrun, Junia; Grim, Christopher; Cheng, Chorng-Ming; McClelland, Michael; Ayers, Sherry; Abbott, Jason; Desai, Prerak; Frye, Jonathan G; Weinstock, George; Hammack, Thomas S; Hanes, Darcy E; Rasmussen, Mark A; Davidson, Maureen K

2014-01-01

188

Complete Genome Sequences of 16 Canadian Strains of Salmonella enterica subsp. enterica Serovar Enteritidis  

PubMed Central

Salmonella enterica subsp. enterica serovar Enteritidis is an important zoonotic food-borne pathogen causing serious human illnesses frequently linked to poultry products. Here, we report fully assembled genome sequences of 16 S.Enteritidis strains with common pulsed-field gel electrophoresis (PFGE) and phage types (8, 13, 13a, and 14b) that predominate in North America. PMID:24762938

Rehman, Muhammad A.; Ziebell, Kim; Nash, John H. E.; Kropinski, Andrew M.; Ross, Ashley; Al-Lami, Mariam; Boerlin, Patrick; Chui, Linda; Devenish, John; Bekal, Sadjia; Graham, Morag; Amoako, Kingsley K.

2014-01-01

189

EFFECT OF REMOVAL OF THE CYTOLYTIC FACTOR OF 'BACILLUS THURINGIENSIS' SUBSP. 'ISRAELENSIS' ON MOSQUITO TOXICITY  

EPA Science Inventory

Solubilized crystal protein of Bacillus thuringiensis subsp. israelensis was fractionated by affinity chromotography using a monoclonal antibody directed against the crystal's 28 kDa peptide. The 28 kDa peptide ws found to be relatively nontoxic to mosquito larvae although it doe...

190

INTERACTIONS BETWEEN BACILLUS THURINGIENSIS SUBSP. ISRAELENSIS AND FATHEAD MINNOWS, PIMEPHALES PROMELAS RAFINESQUE, UNDER LABORATORY CONDITIONS  

EPA Science Inventory

Interactions between Bacillus thuringiensis subsp. israelensis and fathead minnows, Pimephales promelas, were studied in laboratory exposures to two commercial formulations, Vectobac-G and Mosquito Attack. ortality among fatheads exposed to 2.0 x 10 6 to 6.5 x 10 6 CFU/ml with bo...

191

Draft Genome Sequence of the Flagellated Xanthomonas fuscans subsp. fuscans Strain CFBP 4884.  

PubMed

We report the draft genome sequence of the flagellated strain CFBP 4884 of Xanthomonas fuscans subsp. fuscans, which was isolated in an outbreak of common bacterial blight of beans along with non-flagellated strains. Comparative genomics will allow one to decipher the genomic diversity of strains cohabiting in epidemics. PMID:25291773

Indiana, A; Briand, M; Arlat, M; Gagnevin, L; Koebnik, R; Nol, L D; Portier, P; Darrasse, A; Jacques, M A

2014-01-01

192

Genome sequence of the enterobacterial phytopathogen Erwinia carotovora subsp. atroseptica and characterization of virulence factors  

Microsoft Academic Search

The bacterial family Enterobacteriaceae is notable for its well studied human pathogens, including Salmonella, Yersinia, Shigella, and Escherichia spp. However, it also contains several plant pathogens. We report the genome sequence of a plant pathogenic enterobacterium, Erwinia carotovora subsp. atroseptica (Eca) strain SCRI1043, the causative agent of soft rot and blackleg potato diseases. Approximately 33% of Eca genes are not

K. S. Bell; M. Sebaihia; L. Pritchard; M. T. G. Holden; L. J. Hyman; M. C. Holeva; N. R. Thomson; S. D. Bentley; L. J. C. Churcher; K. Mungall; R. Atkin; N. Bason; K. Brooks; T. Chillingworth; K. Clark; J. Doggett; A. Fraser; Z. Hance; H. Hauser; K. Jagels; S. Moule; H. Norbertczak; D. Ormond; C. Price; M. A. Quail; M. Sanders; D. Walker; S. Whitehead; G. P. C. Salmond; P. R. J. Birch; J. Parkhill; I. K. Toth

2004-01-01

193

Assessing potato tubers for susceptibility to bacterial soft rot ( erwinia carotovora subsp. atroseptica )  

Microsoft Academic Search

A laboratory method is described of assessing the susceptibility of tubers to soft rot (Erwinia carotovora subsp.atroseptica). A bacterial suspension is placed in a hole drilled into the tuber cortex, the weighed tubers are placed in damp airtight boxes that are then gassed with nitrogen and incubated for 5 days at 25C. The rotted tissue is washed out and the

W. F. Bourne; D. C. McCalmont; R. L. Wastie

1981-01-01

194

Isolation and characterisation of transposon-induced mutants of Erwinia carotovora subsp. atroseptica exhibiting reduced virulence  

Microsoft Academic Search

The blackleg pathogen Erwinia carotovora subsp. atroseptica (Eca) causes an economically important disease of potatoes. We selected a genetically amenable Eca strain for the genetic analysis of virulence. Tn5 mutagenesis was used to generate nine mutants which exhibited reduced virulence (Rvi-) of strain SCRI1043. Following physiological characterisation, mutants were divided into three classes: (1) auxotrophs; (2) extracellular enzyme mutants; and

Jay C. D. Hinton; Julie M. Sidebotham; Lizbeth J. Hyman; Michel C. M. Prombelon; George P. C. Salmond

1989-01-01

195

The germination characteristics of a population of Zannichellia palustris subsp. pedicellata  

Microsoft Academic Search

In this study the germination characteristics of Zannichellia palustris L. subsp. pedicellata (Wahlemb. et Rosen) Hegi seeds collected from a population along the margin of the Orbetello Lagoon (Tuscany, Italy) was examined. The effect of variations in duration of seed after-ripening and environmental parameters such as light, temperature and culture medium salinity on germination was assessed. In addition, germination ability

Tiziana Lombardi; Stefano Bedini; Antonino Onnis

1996-01-01

196

Isolation of Mycobacterium avium subsp. paratuberculosis from Free-Ranging Birds and Mammals on Livestock Premises  

Microsoft Academic Search

Surveys for Mycobacterium avium subsp. paratuberculosis infection in free-ranging mammals and birds were conducted on nine dairy and beef cattle farms in Wisconsin and Georgia. Specimens were collected from 774 animals representing 25 mammalian and 22 avian species. Specimens of ileum, liver, intestinal lymph nodes, and feces were harvested from the larger mammals; a liver specimen and the gastrointestinal tract

Joseph L. Corn; Elizabeth J. B. Manning; Srinand Sreevatsan; John R. Fischer

2005-01-01

197

Essential oil composition of Tanacetum vulgare subsp. siculum (Guss.) Raimondo et Spadaro (Asteraceae) from Sicily.  

PubMed

Ninety-four components of the essential oils from aerial parts and capitula of Tanacetum vulgare subsp. siculum (Guss.) Raimondo et Spadaro were detected. Alpha-Thujone, beta-thujone and 1,8-cineole were the main constituents of the oils. The analysis allows the assignment of this Tanacetum species to the thujone chemotype. PMID:19476007

Formisano, Carmen; Senatore, Felice; Bruno, Maurizio; Rosselli, Sergio; Bellone, Gabriella; Spadaro, Vivienne

2009-04-01

198

Rocket Immunoelectrophoresis of the Entomocidal Parasporal Crystal of Bacillus thuringiensis subsp. kurstaki  

PubMed Central

Rocket immunoelectrophoresis was used to quantitate the soluble parasporal crystal of Bacillus thuringiensis subsp. kurstaki. The method described is rapid, reliable, specific, and extremely accurate, and it can be used to measure crystal toxin in commercial microbial insecticides that contain a mixture of spores, vegetative cells, and carrier materials. Images PMID:16345656

Andrews, R. E.; Iandolo, J. J.; Campbell, B. S.; Davidson, L. I.; Bulla, L. A.

1980-01-01

199

Complete Genome Sequence of the Quality Control Strain Staphylococcus aureus subsp. aureus ATCC 25923  

PubMed Central

Staphylococcus aureus subsp. aureus ATCC 25923 is commonly used as a control strain for susceptibility testing to antibiotics and as a quality control strain for commercial products. We present the completed genome sequence for the strain, consisting of the chromosome and a 27.5-kb plasmid. PMID:25377701

Treangen, Todd J.; Maybank, Rosslyn A.; Enke, Sana; Friss, Mary Beth; Diviak, Lynn F.; Karaolis, David K. R.; Koren, Sergey; Ondov, Brian; Phillippy, Adam M.; Bergman, Nicholas H.

2014-01-01

200

Mosquito larvicidal activity of transgenic Anabaena PCC 7120 expressing toxin genes from Bacillus thuringiensis subsp. israelensis  

E-print Network

Mosquito larvicidal activity of transgenic Anabaena PCC 7120 expressing toxin genes from Bacillus and the regulatory P20 from Bacillus thuringiensis subsp. israelensis were introduced into the nitrogen by Elsevier B.V. All rights reserved. Keywords: Mosquitocidal Anabaena; N-Endotoxin; Bacillus thuringiensis

Zaritsky, Arieh

201

The nucleotide sequence of a carboxymethylcellulase gene from Pseudomonas fluorescens subsp. cellulosa  

Microsoft Academic Search

The complete nucleotide sequence of the gene coding for one of the carboxymethycellulases (CMCase), expressed by Pseudomonas fluorescens subsp. cellulosa, has been determined. The structural gene consists of an open reading frame, commencing with an ATG start codon, of 2886 base pairs followed by a TAA stop codon. The gene was shown to code for a signal peptide which closely

Judith Hall; Harry J. Gilbert

1988-01-01

202

Genome Sequence of Leuconostoc mesenteroides subsp. cremoris Strain T26, Isolated from Mesophilic Undefined Cheese Starter  

PubMed Central

Leuconostoc is the main group of heterofermentative bacteria found in mesophilic dairy starters. They grow in close symbiosis with the Lactococcus population and are able to degrade citrate. Here we present a draft genome sequence of Leuconostoc mesenteroides subsp. cremoris strain T26. PMID:24903867

Kot, W. P.; Hansen, L. H.; S?rensen, S. J.; Broadbent, J. R.; Vogensen, F. K.; Ardo, Y.

2014-01-01

203

Molecular Evidence of Perinatal Transmission of Bartonella vinsonii subsp. berkhoffii and Bartonella henselae to a Child?  

PubMed Central

Bartonella vinsonii subsp. berkhoffii, Bartonella henselae, or DNA of both organisms was amplified and sequenced from blood, enrichment blood cultures, or autopsy tissues from four family members. Historical and microbiological results support perinatal transmission of Bartonella species in this family. It is of clinical relevance that Bartonella spp. may adversely influence human reproductive performance. PMID:20392912

Breitschwerdt, Edward B.; Maggi, Ricardo G.; Farmer, Peter; Mascarelli, Patricia E.

2010-01-01

204

Mycobacterium avium subsp. paratuberculosis Infection in a Patient with HIV, Germany  

Microsoft Academic Search

Mycobacterium avium subsp. paratuberculosis (MAP), the causative agent of Johne disease in ruminants, has been incriminated as the cause of Crohn disease in humans. We report the first case of human infection with MAP in a patient with HIV; infection was confirmed by obtaining isolates from several different specimen types.

Elvira Richter; Johannes Wessling; Norbert Lgering; Wolfram Domschke; Sabine Rsch-Gerdes

205

Genome Sequence of the Persistent Salmonella enterica subsp. enterica Serotype Senftenberg Strain SS209  

PubMed Central

Salmonella enterica subsp. enterica serotype Senftenberg is an emerging serotype in poultry production which has been found to persist in animals and the farm environment. We report the genome sequence and annotation of the SS209 strain of S. Senftenberg, isolated from a hatchery, which was identified as persistent in broiler chickens. PMID:22493197

Boumart, Zineb; Virlogeux-Payant, Isabelle; Loux, Valentin; Chiapello, Helene; Gendrault, Annie; Gibrat, Jean-Francois; Chemaly, Marianne; Velge, Philippe

2012-01-01

206

Intraspecific variability of the essential oil of Calamintha nepeta subsp. nepeta from Southern Italy (Apulia).  

PubMed

The essential oil of 46 spontaneous plants of Calamintha nepeta (L.) Savi subsp. nepeta growing wild in Sud, Italy (Salento, Apulia), were investigated by GC/MS. Fifty-seven components were identified in the oil representing over the 98% of the total oil composition. Four chemotypes were identified: piperitone oxide, piperitenone oxide, piperitone-menthone and pulegone. PMID:22646908

Negro, C; Notarnicola, S; De Bellis, L; Miceli, A

2013-03-01

207

Novel mutations in TLR genes cause hyporesponsiveness to Mycobacterium avium subsp. paratuberculosis infection  

Microsoft Academic Search

BACKGROUND: Toll like receptors (TLR) play the central role in the recognition of pathogen associated molecular patterns (PAMPs). Mutations in the TLR1, TLR2 and TLR4 genes may change the ability to recognize PAMPs and cause altered responsiveness to the bacterial pathogens. RESULTS: The study presents association between TLR gene mutations and increased susceptibility to Mycobacterium avium subsp. paratuberculosis (MAP) infection.

Mangesh R Bhide; Rastislav Mucha; Ivan Mikula Jr; Lucia Kisova; Rostislav Skrabana; Michal Novak

2009-01-01

208

Oligosaccharide Binding Proteins from Bifidobacterium longum subsp. infantis Reveal a Preference for Host Glycans  

Microsoft Academic Search

Bifidobacterium longum subsp. infantis (B. infantis) is a common member of the infant intestinal microbiota, and it has been characterized by its foraging capacity for human milk oligosaccharides (HMO). Its genome sequence revealed an overabundance of the Family 1 of solute binding proteins (F1SBPs), part of ABC transporters and associated with the import of oligosaccharides. In this study we have

Daniel Garrido; Jae Han Kim; J. Bruce German; Helen E. Raybould; David A. Mills; Vladimir Uversky

2011-01-01

209

Mycobacterium avium Subsp. avium Infection in Four Veal Calves: Differentiation from Intestinal Tuberculosis  

PubMed Central

Mycobacterium avium subsp. avium (Maa) is an intracellular pathogen belonging to the Mycobacterium avium-intracellulare complex (MAC). Reservoirs of MAC are the natural environment, wildlife and domestic animals. In adult bovine, MAC infections are typically caused by Mycobacterium avium subsp. paratuberculosis (Map). Maa infections in bovine are rarely reported but may cause clinical disease and pathological lesions similar to those observed in paratuberculosis or those induced by members of the Mycobacterium tuberculosis complex (MTBC). Therefore, differentiation of MAC from MTBC infection should be attempted, especially if unusual mycobacterial lesions are encountered. Four veal calves from a fattening farm dying with clinical signs of otitis media, fever, and weight loss were submitted for necropsy. Samples from affected organs were taken for histologic investigation, bacteriologic culture, and bacterial specification using PCR. Macroscopic thickening of the intestinal mucosa was induced by granulomatous enteritis and colitis. Intracytoplasmic acid-fast bacteria were detected by Ziehl-Neelsen stains and PCR revealed positive results for Mycobacterium avium subsp. avium. Clinical and pathological changes of Maa infection in veal calves had features of Mycobacterium avium subsp. paratuberculosis and the MTBC. Therefore, Mycobacterium tuberculosis complex infection should be considered in cases of granulomatous enteritis in calves. PMID:24689051

Rossier, Christophe; Baehler, Corinne; Schmitt, Sarah

2014-01-01

210

Detection of Mycobacterium avium subsp. paratuberculosis in Drinking Water and Biofilms Using Quantitative PCR  

EPA Science Inventory

Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne?s disease in domestic animals and has been implicated in Crohn?s disease in humans. Cows infected with Johne?s disease shed large quantities of MAP into soil. Further, MAP has been isolated from surface water, is resi...

211

Draft Genome Sequence of the Flagellated Xanthomonas fuscans subsp. fuscans Strain CFBP 4884  

PubMed Central

We report the draft genome sequence of the flagellated strain CFBP 4884 of Xanthomonas fuscans subsp. fuscans, which was isolated in an outbreak of common bacterial blight of beans along with non-flagellated strains. Comparative genomics will allow one to decipher the genomic diversity of strains cohabiting in epidemics. PMID:25291773

Indiana, A.; Briand, M.; Arlat, M.; Gagnevin, L.; Koebnik, R.; Noel, L. D.; Portier, P.; Darrasse, A.

2014-01-01

212

Development and application of a multilocus sequence typing scheme for Streptococcus gallolyticus subsp. gallolyticus.  

PubMed

Streptococcus gallolyticus subsp. gallolyticus (formerly known as S. bovis biotype I) is a commensal of the gastrointestinal tract in animals and in up to 15% of healthy humans. Furthermore, it is a facultative pathogen that can cause infectious endocarditis, mastitis, and septicemia. The number of infections is increasing, but the transmission routes and zoonotic potential remain unknown. To assess the zoonotic potential and characterize the epidemiological structure of S. gallolyticus subsp. gallolyticus, we established a multilocus sequence typing (MLST) scheme. We amplified and sequenced internal fragments of seven housekeeping genes. The resulting sequences were analyzed with BioNumerics software 6.6 by using the unweighted-pair group method using average linkages algorithm. A total of 101 S. gallolyticus subsp. gallolyticus strains isolated from animals, humans, and environmental samples were analyzed and divided into 50 sequence types. Our first results highlight the importance of this MLST scheme for investigating the epidemiology, transmission patterns, and infection chains of S. gallolyticus subsp. gallolyticus. PMID:24789199

Dumke, J; Hinse, D; Vollmer, T; Knabbe, C; Dreier, J

2014-07-01

213

An IS 900-like sequence found in a Mycobacterium sp. other than Mycobacterium avium subsp. paratuberculosis  

Microsoft Academic Search

The insertion sequence IS900 has been considered specific for Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis) and has, therefore, been used as the target gene for diagnostic PCR of M. paratuberculosis. From a healthy dairy cow we have isolated and characterised a mycobacterium harbouring one copy of a sequence with 94% identity to IS900 at the nucleic acid level. The isolate

Stina Englund; Gran Blske; Karl-Erik Johansson

2002-01-01

214

Chemical, antifungal and cytotoxic evaluation of the essential oil of Thymus zygis subsp. sylvestris  

Microsoft Academic Search

Several Thymus species are used since olden times in traditional medicine, due to recognized therapeutic properties, namely the antimicrobial activity of their essential oils. In the present study we evaluated the composition and the antifungal activity (MIC and MLC) of four type oils obtained from Thymus zygis subsp. sylvestris, an Iberian endemic Lamiaceae, against yeasts, dermatophyte and Aspergillus strains. Moreover,

M. J. Gonalves; M. T. Cruz; C. Cavaleiro; M. C. Lopes; L. Salgueiro

2010-01-01

215

Genome Sequence of Lactococcus lactis subsp. lactis NCDO 2118, a GABA-Producing Strain  

PubMed Central

Lactococcus lactis subsp. lactis NCDO 2118 is a nondairy lactic acid bacterium, a xylose fermenter, and a gamma-aminobutyric acid (GABA) producer isolated from frozen peas. Here, we report the complete genome sequence of L.lactis NCDO 2118, a strain with probiotic potential activity. PMID:25278529

Oliveira, Leticia C.; Saraiva, Tessalia D. L.; Soares, Siomar C.; Ramos, Rommel T. J.; Sa, Pablo H. C. G.; Carneiro, Adriana R.; Miranda, Fabio; Freire, Matheus; Renan, Wendel; Junior, Alberto F. O.; Santos, Anderson R.; Pinto, Anne C.; Souza, Bianca M.; Castro, Camila P.; Diniz, Carlos A. A.; Rocha, Clarissa S.; Mariano, Diego C. B.; de Aguiar, Edgar L.; Folador, Edson L.; Barbosa, Eudes G. V.; Aburjaile, Flavia F.; Goncalves, Lucas A.; Guimaraes, Luis C.; Azevedo, Marcela; Agresti, Pamela C. M.; Silva, Renata F.; Tiwari, Sandeep; Almeida, Sintia S.; Hassan, Syed S.; Pereira, Vanessa B.; Abreu, Vinicius A. C.; Pereira, Ulisses P.; Dorella, Fernanda A.; Carvalho, Alex F.; Pereira, Felipe L.; Leal, Carlos A. G.; Figueiredo, Henrique C. P.; Silva, Artur; Miyoshi, Anderson

2014-01-01

216

Complete Genome Sequence of the Treponema pallidum subsp. pallidum Sea81-4 Strain  

PubMed Central

Using the rabbit model of syphilis, the Sea81-4 strain of Treponema pallidum subsp. pallidum has been found to be more likely than other strains to invade the central nervous system (CNS). To identify possible explanations for this important phenotype at the genomic level, we sequenced the Sea81-4 strain genome. PMID:24744342

Iverson-Cabral, Stefanie L.; King, Jordon C. K.; Molini, Barbara J.; Lukehart, Sheila A.; Centurion-Lara, Arturo

2014-01-01

217

Function and Protective Capacity of Treponema pallidum subsp. pallidum Glycerophosphodiester Phosphodiesterase  

Microsoft Academic Search

Infectious syphilis, caused by the spirochete bacterium Treponema pallidum subsp. pallidum, remains a public health concern worldwide. The immune-response evasion mechanisms employed by T. pallidum are poorly under- stood, and prior attempts to identify immunoprotective antigens for subsequent vaccine design have been unsuc- cessful. Previous investigations conducted in our laboratory identified the T. pallidum glycerophosphodiester phosphodiesterase as a potential immunoprotective

CAROLINE E. CAMERON; CHRISTA CASTRO; SHEILA A. LUKEHART; WESLEY C. VAN VOORHIS

1998-01-01

218

Complete Genome Sequence of the Treponema pallidum subsp. pallidum Sea81-4 Strain.  

PubMed

Using the rabbit model of syphilis, the Sea81-4 strain of Treponema pallidum subsp. pallidum has been found to be more likely than other strains to invade the central nervous system (CNS). To identify possible explanations for this important phenotype at the genomic level, we sequenced the Sea81-4 strain genome. PMID:24744342

Giacani, Lorenzo; Iverson-Cabral, Stefanie L; King, Jordon C K; Molini, Barbara J; Lukehart, Sheila A; Centurion-Lara, Arturo

2014-01-01

219

Broad Conservation of Milk Utilization Genes in Bifidobacterium longum subsp. infantis as Revealed by Comparative Genomic Hybridization ?  

PubMed Central

Human milk oligosaccharides (HMOs) are the third-largest solid component of milk. Their structural complexity renders them nondigestible to the host but liable to hydrolytic enzymes of the infant colonic microbiota. Bifidobacteria and, frequently, Bifidobacterium longum strains predominate the colonic microbiota of exclusively breast-fed infants. Among the three recognized subspecies of B. longum, B. longum subsp. infantis achieves high levels of cell growth on HMOs and is associated with early colonization of the infant gut. The B. longum subsp. infantis ATCC 15697 genome features five distinct gene clusters with the predicted capacity to bind, cleave, and import milk oligosaccharides. Comparative genomic hybridizations (CGHs) were used to associate genotypic biomarkers among 15 B. longum strains exhibiting various HMO utilization phenotypes and host associations. Multilocus sequence typing provided taxonomic subspecies designations and grouped the strains between B. longum subsp. infantis and B. longum subsp. longum. CGH analysis determined that HMO utilization gene regions are exclusively conserved across all B. longum subsp. infantis strains capable of growth on HMOs and have diverged in B. longum subsp. longum strains that cannot grow on HMOs. These regions contain fucosidases, sialidases, glycosyl hydrolases, ABC transporters, and family 1 solute binding proteins and are likely needed for efficient metabolism of HMOs. Urea metabolism genes and their activity were exclusively conserved in B. longum subsp. infantis. These results imply that the B. longum has at least two distinct subspecies: B. longum subsp. infantis, specialized to utilize milk carbon, and B. longum subsp. longum, specialized for plant-derived carbon metabolism. PMID:20802066

LoCascio, Riccardo G.; Desai, Prerak; Sela, David A.; Weimer, Bart; Mills, David A.

2010-01-01

220

Effect of Three Factors in Cheese Production (pH, Salt, and Heat) on Mycobacterium avium subsp. paratuberculosis Viability  

PubMed Central

Low pH and salt are two factors contributing to the inactivation of bacterial pathogens during a 60-day curing period for cheese. The kinetics of inactivation for Mycobacterium avium subsp. paratuberculosis strains ATCC 19698 and Dominic were measured at 20C under different pH and NaCl conditions commonly used in processing cheese. The corresponding D values (decimal reduction times; the time required to kill 1 log10 concentration of bacteria) were measured. Also measured were the D values for heat-treated and nonheated M. avium subsp. paratuberculosis in 50 mM acetate buffer (pH 5.0, 2% [wt/vol] NaCl) and a soft white Hispanic-style cheese (pH 6.0, 2% [wt/vol] NaCl). Samples were removed at various intervals until no viable cells were detected using the radiometric culture method (BACTEC) for enumeration of M. avium subsp. paratuberculosis. NaCl had little or no effect on the inactivation of M. avium subsp. paratuberculosis, and increasing NaCl concentrations were not associated with decreasing D values (faster killing) in the acetate buffer. Lower pHs, however, were significantly correlated with decreasing D values of M. avium subsp. paratuberculosis in the acetate buffer. The D values for heat-treated M. avium subsp. paratuberculosis ATCC 19698 in the cheese were higher than those predicted by studies done in acetate buffer. The heat-treated M. avium subsp. paratuberculosis strains had lower D values than the nonheated cells (faster killing) both in the acetate buffer (pH 5, 2% [wt/vol] NaCl) and in the soft white cheese. The D value for heat-treated M. avium subsp. paratuberculosis ATCC 19698 in the cheese (36.5 days) suggests that heat treatment of raw milk coupled with a 60-day curing period will inactivate about 103 cells of M. avium subsp. paratuberculosis per ml. PMID:10742208

Sung, Nackmoon; Collins, Michael T.

2000-01-01

221

Regulation of the production of extracellular pectinase, cellulase, and protease in the soft rot bacterium Erwinia carotovora subsp. carotovora: evidence that aepH of E. carotovora subsp. carotovora 71 activates gene expression in E. carotovora subsp. carotovora, E. carotovora subsp. atroseptica, and Escherichia coli.  

PubMed Central

The production of pectolytic enzymes (pectate lyase [Pel] and polygalacturonase [Peh]), cellulase (Cel), and protease (Prt) is activated in the soft rot bacterium Erwinia carotovora subsp. carotovora by aepA (activator of extracellular protein production) and celery extract (Y. Liu, H. Murata, A. Chatterjee, and A. K. Chatterjee, Mol. Plant-Microbe Interact. 6:299-308, 1993). We recently isolated a new class of mutants of strain E. carotovora subsp. carotovora 71 which overproduces Pel, Peh, Cel, and Prt. From the overproducing strain AC5034, we identified an activator locus, designated aepH*, which stimulated Pel, Peh, Cel, and Prt production in E. carotovora subsp. carotovora 71 or its derivatives. The nucleotide sequence of the aepH* DNA segment revealed an open reading frame of 141 bp that could encode a small (5.45-kDa) highly basic (pI 11.7) protein of 47 amino acid residues. Analyses of deletions and MudI insertions indicated that the activator function required the 508-bp DNA segment which contains this open reading frame. The wild-type locus, aepH+, is localized within a DNA segment upstream of aepA. An AepH- strain constructed by exchanging aepH+ with aepH*::MudI was deficient in Pel, Peh, Cel, and Prt production; exoenzyme production was restored upon the introduction of a plasmid carrying aepH+ or aepH*. Plasmids carrying either aepH+ or aepH* activated the production of Pel-1, Peh-1, and Cel in Escherichia coli HB101 carrying the cognate genes. The aepH effect in E. coli was due to the activation of transcription, as indicated by assays of pel-1 and peh-1 mRNAs. The aepH+ and aepH* plasmids also stimulated Pel, Peh, Cel, and Prt production in other wild-type E. carotovora subsp. carotovora strains as well as in E. carotovora subsp. atroseptica. Although the stimulatory effect was generally more pronounced with aepH* than with aepH+, the extent of activation in the wild-type strains depended upon the bacterial strain and the growth medium. Southern blot hybridization revealed the presence of aepH homologs in E. carotovora subsp. carotovora and E. carotovora subsp. atroseptica, and provided physical evidence for linkage between aepA and aepH homologs in genomes of these bacteria. We conclude that aepH-mediated activation of exoprotein gene expression is a feature common to most strains of E. carotovora. Images PMID:7944360

Murata, H; Chatterjee, A; Liu, Y; Chatterjee, A K

1994-01-01

222

Molecular Organization of the 25S-18S rDNA IGS of Fagus sylvatica and Quercus suber: A Comparative Analysis  

PubMed Central

The 35S ribosomal DNA (rDNA) units, repeated in tandem at one or more chromosomal loci, are separated by an intergenic spacer (IGS) containing functional elements involved in the regulation of transcription of downstream rRNA genes. In the present work, we have compared the IGS molecular organizations in two divergent species of Fagaceae, Fagus sylvatica and Quercus suber, aiming to comprehend the evolution of the IGS sequences within the family. Self- and cross-hybridization FISH was done on representative species of the Fagaceae. The IGS length variability and the methylation level of 18 and 25S rRNA genes were assessed in representatives of three genera of this family: Fagus, Quercus and Castanea. The intergenic spacers in Beech and Cork Oak showed similar overall organizations comprising putative functional elements needed for rRNA gene activity and containing a non-transcribed spacer (NTS), a promoter region, and a 5?-external transcribed spacer. In the NTS: the sub-repeats structure in Beech is more organized than in Cork Oak, sharing some short motifs which results in the lowest sequence similarity of the entire IGS; the AT-rich region differed in both spacers by a GC-rich block inserted in Cork Oak. The 5?-ETS is the region with the higher similarity, having nonetheless different lengths. FISH with the NTS-5?-ETS revealed fainter signals in cross-hybridization in agreement with the divergence between genera. The diversity of IGS lengths revealed variants from ?2 kb in Fagus, and Quercus up to 5.3 kb in Castanea, and a lack of correlation between the number of variants and the number of rDNA loci in several species. Methylation of 25S Bam HI site was confirmed in all species and detected for the first time in the 18S of Q. suber and Q. faginea. These results provide important clues for the evolutionary trends of the rDNA 25S-18S IGS in the Fagaceae family. PMID:24893289

Inacio, Vera; Rocheta, Margarida; Morais-Cecilio, Leonor

2014-01-01

223

Isolation of Mycobacterium avium subsp. paratuberculosis from Free-Ranging Birds and Mammals on Livestock Premises  

PubMed Central

Surveys for Mycobacterium avium subsp. paratuberculosis infection in free-ranging mammals and birds were conducted on nine dairy and beef cattle farms in Wisconsin and Georgia. Specimens were collected from 774 animals representing 25 mammalian and 22 avian species. Specimens of ileum, liver, intestinal lymph nodes, and feces were harvested from the larger mammals; a liver specimen and the gastrointestinal tract were harvested from birds and small mammals. Cultures were performed by using radiometric culture and acid-fast isolates were identified by 16S/IS900/IS1311 PCR and mycobactin dependency characteristics. M. avium subsp. paratuberculosis was cultured from tissues and feces from 39 samples from 30 animals representing nine mammalian and three avian species. The prevalence of infected wild animals by premises ranged from 2.7 to 8.3% in Wisconsin and from 0 to 6.0% in Georgia. Shedding was documented in seven (0.9%) animals: three raccoons, two armadillos, one opossum, and one feral cat. The use of two highly polymorphic short sequence repeat loci for analysis of 29 of the 39 strains identified 10 alleles. One allelic pattern broadly shared in domestic ruminants (7,5) appeared in approximately one-third of the wildlife M. avium subsp. paratuberculosis isolates studied. Given the few cases of shedding by free-ranging animals compared to the volume of contaminated manure produced by infected domestic ruminant livestock, contamination of the farm environment by infected wildlife was negligible. Wildlife may, however, have epidemiological significance for farms where M. avium subsp. paratuberculosis recently has been eliminated or on farms free of M. avium subsp. paratuberculosis but located in the geographic vicinity of farms with infected livestock. PMID:16269731

Corn, Joseph L.; Manning, Elizabeth J. B.; Sreevatsan, Srinand; Fischer, John R.

2005-01-01

224

Induction of B Cell Responses upon Experimental Infection of Neonatal Calves with Mycobacterium avium subsp. paratuberculosis ?  

PubMed Central

The objective of this study was to determine if experimental infection of neonatal calves with Mycobacterium avium subsp. paratuberculosis would invoke changes in the percentages of total B cells in the peripheral blood mononuclear cell population and of subpopulations of B cells as determined by CD5, CD25, and CD45RO markers during a 12-month period. Experimental infection groups included control (noninfected), oral (infected with M. avium subsp. paratuberculosis strain K-10), oral/DXM (pretreatment with dexamethasone before oral inoculation), i.p. (intraperitoneal inoculation), and oral/M (oral inoculation with mucosal scrapings from a cow with clinical disease) groups. Over the course of the study, the percentages of total B cells in nonstimulated and antigen-stimulated cell cultures increased for oral and i.p. group calves, with the highest percentages noted at 3 and 6 months. Oral/M group calves had increased percentages of activated B cells, as determined by CD5dim and CD5bright markers, at 9 and 12 months. Experimental infection by all methods resulted in increased expression of CD25+ and CD45RO+ B cells early in the study, but the most significant results were observed at 12 months for oral/DXM and oral/M group calves. Immunoblot analyses with a whole-cell sonicate of M. avium subsp. paratuberculosis demonstrated the most reactivity with sera from i.p. group calves and the least reactivity with sera from oral group calves. Further evidence of M. avium subsp. paratuberculosis-specific antibody responses in the i.p. group calves was demonstrated using the ethanol vortex enzyme-linked immunosorbent assay (EvELISA) method. In summary, an induction of B cell responses was noted after experimental infection with M. avium subsp. paratuberculosis, with differences in responses noted according to the method of experimental inoculation. PMID:21543587

Stabel, J. R.; Bannantine, J. P.; Eda, Shigetoshi; Robbe-Austerman, S.

2011-01-01

225

The influence of stemflow from an European Beech Tree (Fagus Sylvatica L.) on soil solution and seepage fluxes  

NASA Astrophysics Data System (ADS)

European Beech (Fagus sylcatica L.) is particularly prone to produce large amounts of stemflow even during comparatively small precipitation events. This may lead to preferential flow and solute transport to greater depths next to the stem at lower precipitation heights than would be expected without considering water redistribution by the canopy. In this study we investigated the influence of beech stemflow on soil solution and seepage fluxes, based on observed quality of all precipitation components as well as soil water. For estimation of transport, the soil water flow was modeled. We measured concentrations of Na+, K+, Mg2+, Ca2+, NH4+-N, NO3--N, Dissolved Organic Nitrogen (DON) and Dissolved Organic Carbon (DOC) in throughfall, stemflow and soil solution at depths of 10 cm and 30 cm and stem distances of 10 cm, 40 cm and 100 cm during autumn 2012 and spring and summer 2013. Throughfall and stemflow were sampled at 38 precipitation events during summer and autumn 2012 and summer 2013 from 192 (throughfall) and 16 (stemflow) collectors, respectively. Soil solutions were collected on 10 events during autumn 2012 and spring and summer 2013. Element fluxes were calculated from the chemical and hydrological measurements and model results. Water flow through the soil was calculated using the model VS2DTI and was based on Richard's equation and the model of van Genuchten and Mualem for predicting unsaturated hydraulic conductivity. The model also accounted for evapotranspiration, which was estimated using the Penman-Monteith equation with meteorological data from a nearby weather station. Longterm time series of throughfall and stemflow were estimated based on the observed relations and using rainfall data from the same weather station. Since the actual stemflow infiltration area was unknown, two scenarios with assumed infiltration areas of 1 m and 2.76 m were calculated. All concentrations and fluxes were within the range of published results. However, stemflow fluxes could not be estimated reliably due to missing information on the actual infiltration area. Our data suggest that the influence of stemflow on soil solution seems to reach to at least up to 40 cm stem distance but not as far as 100 cm distance from the stem. We observed lower element concentrations in soil solution next to the stem, which may be a result of the locally increased water input, therefore diluting element concentrations. Element seepage fluxes calculated from modeled water fluxes were lower than measured fluxes, due to an overestimation of transpiration by the model. With the given setup the model did not indicate a significant importance of stemflow on water or element seepage fluxes. Further development should include enhancing the model to account for preferential flow patterns, recalculating of evapotranspiration and consideration of its spatial distribution and integrating in situ measured soil properties.

Dalla Valle, Nicolas; Michalzik, Beate; Hildebrandt, Anke

2014-05-01

226

Antigenicity of Recombinant Maltose Binding Protein-Mycobacterium avium subsp. paratuberculosis Fusion Proteins with and without Factor Xa Cleaving  

PubMed Central

Mycobacterium avium subsp. paratuberculosis causes Johne's disease (JD) in ruminants. Proteomic studies have shown that M. avium subsp. paratuberculosis expresses certain proteins when exposed to in vitro physiological stress conditions similar to the conditions experienced within a host during natural infection. Such proteins are hypothesized to be expressed in vivo, are recognized by the host immune system, and may be of potential use in the diagnosis of JD. In this study, 50 recombinant maltose binding protein (MBP)-M. avium subsp. paratuberculosis fusion proteins were evaluated using serum samples from sheep infected with M. avium subsp. paratuberculosis, and 29 (58%) were found to be antigenic. Among 50 fusion proteins, 10 were evaluated in MBP fusion and factor Xa-cleaved forms. A total of 31 proteins (62%) were found to be antigenic in either MBP fusion or factor Xa-cleaved forms. Antigenicity after cleavage and removal of the MBP tag was marginally enhanced. PMID:24132604

Begg, Douglas J.; Purdie, Auriol C.; Bannantine, John P.; Whittington, Richard J.

2013-01-01

227

Changes in transcription profiles reflect strain contributions to defined cultures of Lactococcus lactis subsp. cremoris during milk fermentation  

Microsoft Academic Search

Cheddar cheese production uses mixed starters composed of Lactococcus lactis subsp. cremoris strains with complementary or competing enzymatic activity. However, strain interactions within the same subspecies are difficult\\u000a to investigate by conventional microbiological methods. This study uses fluorescent RNA arbitrarily primed PCR (FRAP-PCR)\\u000a to analyze the association of three L. lactis subsp. cremoris strains (LL074, LL225, and LL390 with proteinase

Fabien Dachet; Denis Roy; Gisle LaPointe

228

Contrasting Results of Culture-Dependent and Molecular Analyses of Mycobacterium avium subsp. paratuberculosis from Wood Bison  

PubMed Central

Reduced to near extinction in the late 1800s, a number of wood bison populations (Bison bison athabascae) have been re-established through reintroduction initiatives. Although an invaluable tool for conservation, translocation of animals can spread infectious agents to new areas or expose animals to pathogens in their new environment. Mycobacterium avium subsp. paratuberculosis, a bacterium that causes chronic enteritis in ruminants, is among the pathogens of potential concern for wood bison management and conservation. In order to inform translocation decisions, our objectives were to determine the M. avium subsp. paratuberculosis infection status of wood bison herds in Canada and to culture and genetically characterize the infective strain(s). We tested fecal samples from bison (n = 267) in nine herds using direct PCR for three M. avium subsp. paratuberculosis-specific genetic targets with different copy numbers within the M. avium subsp. paratuberculosis genome. Restriction enzyme analysis (REA) and sequencing of IS1311 were performed on seven samples from five different herds. We also evaluated a panel of different culture conditions for their ability to support M. avium subsp. paratuberculosis growth from feces and tissues of direct-PCR-positive animals. Eighty-one fecal samples (30%) tested positive using direct IS900 PCR, with positive samples from all nine herds; of these, 75% and 21% were also positive using ISMAP02 and F57, respectively. None of the culture conditions supported the growth of M. avium subsp. paratuberculosis from PCR-positive samples. IS1311 REA and sequencing indicate that at least two different M. avium subsp. paratuberculosis strain types exist in Canadian wood bison. The presence of different M. avium subsp. paratuberculosis strains among wood bison herds should be considered in the planning of translocations. PMID:23686265

De Buck, Jeroen; Elkin, Brett; Kutz, Susan; van der Meer, Frank; Orsel, Karin

2013-01-01

229

[Detection of bacteriophages of siphoviridae family in Erwinia carotovora subsp. carotovora].  

PubMed

It was established that the polylysogenic phage system of culture Erwinia carotovora subsp. carotovora 91P includes: a) defective bacteriophages of Myoviridae family, which are displayed as macromolecular carotovoricins b) valuable highly unstable temperate phage, which can be attributed to the family Myoviridae, and which, perhaps, is an analogue of phage ZF40 [6], and c) resistant to osmotic shock temperate phage of family Siphoviridae. This phage, called TIRI, consists of isometric head 50 nm in diameter and a rigid tail structure 203 nm long. A characteristic feature of the phage tail is an evident transverse striation, which is also indicative for the tail-like particle of the defective temperate phage of the strain 48A-7/4b. In general, the phage system of E carotovora subsp. carotovora is similar to Pseudomonas aeruginosa with its R- and F-bacteriocins, and phages of the families Myoviridae and Siphoviridae. PMID:22308753

Ivanitsa, T V; Tovkach, F I

2011-01-01

230

Insertion and amplification of foreign genes in the Lactococcus lactis subsp. lactis chromosome.  

PubMed Central

The plasmid pE194 is unable to replicate in Lactococcus lactis subsp. lactis (formerly Streptococcus lactis). When linked to resident bacteriophage sequences, pE194 was able to integrate into the L. lactis subsp. lactis chromosome either by Campbell-like recombination or by double crossing over with deletion. Integration occurred into the DNA of the prophage and prevented its multiplication. When a selective pressure was applied to an integrant in which pE194 was flanked by two direct repeats of prophage fragment, amplification of pE194 and the prophage fragment was observed. The pE194 copy number was assessed at six to nine, and amplification was stable upon growth under nonselective conditions. Images PMID:2504115

Chopin, M C; Chopin, A; Rouault, A; Galleron, N

1989-01-01

231

Genomic Diversity of Erwinia carotovora subsp. carotovora and Its Correlation with Virulence  

PubMed Central

We used genetic and biochemical methods to examine the genomic diversity of the enterobacterial plant pathogen Erwinia carotovora subsp. carotovora. The results obtained with each method showed that E. carotovora subsp. carotovora strains isolated from one ecological niche, potato plants, are surprisingly diverse compared to related pathogens. A comparison of 23 partial mdh sequences revealed a maximum pairwise difference of 10.49% and an average pairwise difference of 2.13%, values which are much greater than the maximum variation (1.81%) and average variation (0.75%) previously reported for Escherichia coli. Pulsed-field gel electrophoresis analysis of I-CeuI-digested genomic DNA revealed seven rrn operons in all E. carotovora subsp. carotovora strains examined except strain WPP17, which had only six copies. We identified 26 I-CeuI restriction fragment length polymorphism patterns and observed significant polymorphism in fragment sizes ranging from 100 to 450 kb for all strains. We detected large plasmids in two strains, including the model strain E. carotovora subsp. carotovora 71. The two least virulent strains had an unusual chromosomal structure, suggesting that a particular pulsotype is correlated with virulence. To compare chromosomal organization of multiple enterobacterial genomes, several genes were mapped onto I-CeuI fragments. We identified portions of the genome that appear to be conserved across enterobacteria and portions that have undergone genome rearrangements. We found that the least virulent strain, WPP17, failed to oxidize cellobiose and was missing several hrp and hrc genes. The unexpected variability among isolates obtained from clonal hosts in one region and in one season suggests that factors other than the host plant, potato, drive the evolution of this common environmental bacterium and key plant pathogen. PMID:15128563

Yap, Mee-Ngan; Barak, Jeri D.; Charkowski, Amy O.

2004-01-01

232

Novel phytases from Bifidobacterium pseudocatenulatum ATCC 27919 and Bifidobacterium longum subsp. infantis ATCC 15697.  

PubMed

Two novel phytases have been characterized from Bifidobacterium pseudocatenulatum and Bifidobacterium longum subsp. infantis. The enzymes belong to a new subclass within the histidine acid phytases, are highly specific for the hydrolysis of phytate, and render myo-inositol triphosphate as the final hydrolysis product. They represent the first phytases characterized from this group of probiotic microorganisms, opening the possibilities for their use in the processing of high-phytate-content foods. PMID:22582052

Tamayo-Ramos, Juan Antonio; Sanz-Penella, Juan Mario; Yebra, Mara J; Monedero, Vicente; Haros, Monika

2012-07-01

233

Novel Phytases from Bifidobacterium pseudocatenulatum ATCC 27919 and Bifidobacterium longum subsp. infantis ATCC 15697  

PubMed Central

Two novel phytases have been characterized from Bifidobacterium pseudocatenulatum and Bifidobacterium longum subsp. infantis. The enzymes belong to a new subclass within the histidine acid phytases, are highly specific for the hydrolysis of phytate, and render myo-inositol triphosphate as the final hydrolysis product. They represent the first phytases characterized from this group of probiotic microorganisms, opening the possibilities for their use in the processing of high-phytate-content foods. PMID:22582052

Tamayo-Ramos, Juan Antonio; Sanz-Penella, Juan Mario; Yebra, Mara J.

2012-01-01

234

Complete genome sequence of a plant associated bacterium Bacillus amyloliquefaciens subsp. plantarum UCMB5033.  

PubMed

Bacillus amyloliquefaciens subsp. plantarum UCMB5033 is of special interest for its ability to promote host plant growth through production of stimulating compounds and suppression of soil borne pathogens by synthesizing antibacterial and antifungal metabolites or priming plant defense as induced systemic resistance. The genome of B. amyloliquefaciens UCMB5033 comprises a 4,071,167 bp long circular chromosome that consists of 3,912 protein-coding genes, 86 tRNA genes and 10 rRNA operons. PMID:25197456

Niazi, Adnan; Manzoor, Shahid; Bejai, Sarosh; Meijer, Johan; Bongcam-Rudloff, Erik

2014-06-15

235

Characterization of the Highly Autolytic Lactococcus lactis subsp. cremoris Strains CO and 2250  

PubMed Central

Two highly autolytic Lactococcus lactis subsp. cremoris strains (CO and 2250) were selected and analyzed for their autolytic properties. Both strains showed maximum lysis when grown in M17 broth containing a limiting concentration of glucose (0.4 to 0.5%) as the carbohydrate source. Lysis did not vary greatly with pH or temperature but was reduced when strains were grown on lactose or galactose. Growth in M17 containing excess glucose (1%) prevented autolysis, although rapid lysis of L. lactis subsp. cremoris CO did occur in the presence of 1% glucose if sodium fluoride (an inhibitor of glycolysis) was added to the medium. Maximum cell lysis in a buffer system was observed early in the stationary phase, and for CO, two pH optima were observed for log-phase and stationary-phase cells (6.5 and 8.5, respectively). Autolysins were extracted from the cell wall fraction of each strain by using either 4% sodium dodecyl sulfate (SDS), 6 M guanidine hydrochloride, or 4 M lithium chloride, and their activities were analyzed by renaturing SDS-polyacrylamide gel electrophoresis on gels containing Micrococcus luteus or L. lactis subsp. cremoris CO cells as the substrate. More than one lytic band was observed on each substrate, with the major band having an apparent molecular mass of 48 kDa for CO. Each lytic band was present throughout growth and lysis. These results suggest that at least two different autolytic enzymes are present in the autolytic L. lactis subsp. cremoris strains. The presence of the lactococcal cell wall hydrolase gene, acmA (G. Buist, J. Kok, K. J. Leenhouts, M. Dabrowska, G. Venema, and A. J. Haandrikman, J. Bacteriol. 177:1554-1563, 1995), in strains 2250 and CO was confirmed by Southern hybridization. Analysis of an acmA deletion mutant of 2250 confirmed that the gene was involved in cell separation and had a role in cell lysis. PMID:16535702

Riepe, H. R.; Pillidge, C. J.; Gopal, P. K.; Mckay, L. L.

1997-01-01

236

Avian wildlife reservoir of Campylobacter fetus subsp. jejuni, Yersinia spp., and Salmonella spp. in Norway.  

PubMed

Cloacal swabs from 540 wild-living birds were cultured for Campylobacter fetus subsp. jejuni, Yersinia spp., and Salmonella spp. The carrier rates detected were as follows: C. fetus subsp. jejuni, 28.4%; Yersinia spp., 1.2%; and Salmonella spp., 0.8%. All birds were apparently healthy when captured. C. fetus subsp. jejuni was isolated from 11 of the 40 bird species examined. Among birds inhabiting the city of Oslo, the highest isolation rate was found in crows (Corvus corone cornix) (89.8%), followed by gulls (Larus spp.) (50.0%) and domestic pigeons (Columba livia domesticus) (4.2%). The gulls and crows scavenge on refuse dumps. High carrier rates were also detected among the following birds from nonurban, coastal areas: puffin (Fratercula arctica) (51.3%), common tern (Sterna hirundo) (5.6%), common gull (Larus canus) (18.9%), black-headed gull (Larus ridibundus) (13.2%), and herring gull (Larus argentatus) (4.2%). The list of species harboring C. fetus subsp. jejuni also includes the Ural owl (Strix uralensis), goldeneye (Bucephala clangula), and reed bunting (Emberiza schoeniclus). The following five Yersinia strains were isolated: Y. kristensenii (two strains), Y. intermedia (two strains), and "Yersinia X2" (one strain). Four strains belonging to the genus Salmonella were isolated from three different species of gulls. These isolates were identified as S. typhimurium, S. indiana, and S. djugu. The results indicate that campylobacters are a normal component of the intestinal flora in several bird species, whereas Salmonella and Yersinia carriers are more sporadic. PMID:6338824

Kapperud, G; Rosef, O

1983-02-01

237

[The characteristic of the colispecific bacteriocins of Erwinia carotovora subsp. carotovora Ec153].  

PubMed

It has been shown for the first time that macromolecular carotovoricins from Erwinia carotovora subsp. carotovora Ec153 strain are active to Escherichia coli and posses endonuclease activity. It has been established that 19.1% of strains isolated from the patients are sensitive to these bacteriocins. The type and the form of these particles have been also determined and they show resemblance with phage objects. PMID:19938602

Krylova, E D; Tovkach, F I

2009-01-01

238

Mapping of the chromosome of bacteria Erwinia carotovora subsp. atroseptica 3-2  

SciTech Connect

Two Hfr-like donor strains of bacteria Erwinia carotovora subsp. atroseptica (Eca) 3-2 were developed by integration into the chromosome of the conjugative plasmid R471a via homology with transposon Tn9. Using these and two donor strains created earlier, we constructed the genetic map of a fragment of the chromosome of strain Eca 3-2. The location of 14 loci is shown in this map. 15 refs., 3 figs., 1 tab.

Nikolaichik, E.A.; Pesnyakevich, A.G. [Belarussian State Univ., Minsk (Belarus)

1995-07-01

239

Resistance of tubers from different potato cultivars to soft rot caused by Erwinia carotovora subsp. atroseptica  

Microsoft Academic Search

Mechanically harvested tubers of 14 potato cultivars grown on both loamy sand and silt loam soils were evaluated for resistance\\u000a to bacterial soft rot caused byErwinia carotovora subsp.atroseptica. Cultivars were also assayed for calcium and dry matter content to determine possible correlations with soft rot resistance.\\u000a \\u000a Resistance of potato tubers to bacterial soft rot was assayed after harvest by inoculating

Kuo-Ching Tzeng; Raymond G. McGuire; Arthur Kelman

1990-01-01

240

Complete Genome Sequence of Type Strain Pasteurella multocida subsp. multocida ATCC 43137  

PubMed Central

Soft-tissue infection by Pasteurella multocida in humans is usually associated with a dog- or cat-related injury, and these infections can become aggressive. We sequenced the type strain P.multocida subsp. multocida ATCC 43137 into a single closed chromosome consisting of 2,271,840 bp (40.4% G+C content), which is currently available in the NCBI GenBank under the accession number CP008918. PMID:25342682

Davenport, K. W.; Daligault, H. E.; Minogue, T. D.; Bishop-Lilly, K. A.; Bruce, D. C.; Chain, P. S.; Coyne, S. R.; Frey, K. G.; Jaissle, J.; Koroleva, G. I.; Ladner, J. T.; Lo, C. C.; Palacios, G. F.; Redden, C. L.; Scholz, M. B.; Teshima, H.

2014-01-01

241

Experimental Paratuberculosis in Calves following Inoculation with a Rabbit Isolate of Mycobacterium avium subsp. paratuberculosis  

Microsoft Academic Search

The role of wildlife species in the epidemiology of paratuberculosis has been the subject of increased research efforts following the discovery of natural paratuberculosis in free-living rabbits from farms in east Scotland. This paper describes the experimental inoculation of young calves with an isolate of Mycobacterium avium subsp. paratuberculosis recovered from a free-living rabbit. After a 6-month incubation period, all

P. M. Beard; K. Stevenson; A. Pirie; K. Rudge; D. Buxton; S. M. Rhind; M. C. Sinclair; L. A. Wildblood; D. G. Jones; J. M. Sharp

2001-01-01

242

Characterization of the Highly Autolytic Lactococcus lactis subsp. cremoris Strains CO and 2250  

Microsoft Academic Search

Two highly autolytic Lactococcus lactis subsp. cremoris strains (CO and 2250) were selected and analyzed for their autolytic properties. Both strains showed maximum lysis when grown in M17 broth containing a limiting concentration of glucose (0.4 to 0.5%) as the carbohydrate source. Lysis did not vary greatly with pH or temperature but was reduced when strains were grown on lactose

HEIDI R. RIEPE; CHRISTOPHER J. PILLIDGE; PRAMOD K. GOPAL; LARRY L. MCKAY

243

Hydraulic redistribution in Eucalyptus kochii subsp. borealis with variable access to fresh groundwater  

Microsoft Academic Search

Salinity caused by land clearing is an important cause of land degradation in the Western Australian wheatbelt. Returning\\u000a a proportion of the cleared land to higher water use perennial vegetation is one option for reducing or slowing the salinisation\\u000a of land. Over the course of a year patterns of water use by Eucalyptus kochii subsp borealis (C. Gardner) D. Nicolle,

K. Brooksbank; D. A. White; E. J. Veneklaas; J. L. Carter

2011-01-01

244

Bilateral polyploidization in Dactylis glomerata L. subsp. lusitanica : occurrence, morphological and genetic characteristics of first polyploids  

Microsoft Academic Search

Summary InDactylis glomerata L. subsp.lusitanica, triploid and tetraploid plants were obtained by bilateral sexual polyploidization in crosses between diploid parents known to produce 2n gametes. The polyploid and diploid progeny were compared for allozyme diversity (allele number and heterozygosity), phenological (pollen fertility, inflorescence emergence date), cellular (stomatic cell size) and morphological characters (vegetative biomass, seed weight, total seed number per

F. Bretagnolle; R. Lumaret

1995-01-01

245

Antioxidant and antiproliferative activity of Hypericum hircinum L. subsp. majus (Aiton) N. Robson essential oil  

Microsoft Academic Search

This study was undertaken to assess the antioxidant and antiproliferative potential of the essential oil of Hypericum hircinum L. subsp. majus (Aiton) N. Robson. Analysis of the oil composition revealed that sesquiterpene hydrocarbons (69.3%) dominate, cis-?-guaiene, ?-selinene and (E)-caryophyllene being the most representative. Significant values of antioxidant activity were found using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2?-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays.

Luana Quassinti; Giulio Lupidi; Filippo Maggi; Gianni Sagratini; Fabrizio Papa; Sauro Vittori; Armandodoriano Bianco; Massimo Bramucci

2012-01-01

246

Zur Cytotaxonomie von Veronica chamaedrys L., I.: subsp. vindobonensis M. Fischer , eine neue, diploide Sippe  

Microsoft Academic Search

Auer typischerVeronica chamaedrys L. findet sich in sterreich eine Sippe mit deutlich dichterer und krzerer Behaarung der Sepalen, meist merklich tiefer eingeschnittenen Laubblttern, immer rein zweizeiliger Behaarung der Hauptachse und hellblauen, seltener rosa Blten. Diese Sippe wurde auf Grund ihrer diploiden Chromosomenzahl (2 n=16) entdeckt und wird alsVeronica chamaedrys L. subsp.vindobonensis M.Fischer\\u000a neu beschrieben. Sie wchst nur an trocken-warmen Standorten

Manfred Fischer

1970-01-01

247

Utilization of citrate by Leuconostoc mesenteroides subsp. cremoris in continuous culture  

Microsoft Academic Search

Summary Leuconostoc mesenteroides subsp.cremoris was grown in continuous culture in lactose medium with varying citrate concentrations. All citrate (10, 25, 50 and 75 mMol\\/l) was used and lactose consumption increased with increasing initial citrate concentrations correlate with an increase of dry cell weight. Citrate lead to an increase of acetate and could be a source of ATPvia acetate kinase pathway.

P. Schmitt; C. Divis; C. Merlot

1990-01-01

248

Complete Genome Sequence of Lactococcus lactis subsp. lactis KLDS4.0325  

PubMed Central

We report the complete genome sequence of Lactococcus lactis subsp. lactis KLDS4.0325, a probiotic bacterium isolated from homemade koumiss in Xinjiang, China. We have determined the complete genome sequence of strain KLDS4.0325, which consists of a chromosome and three plasmids and reveals genes that are likely to be involved in dairy fermentation and that have probiotic qualities. PMID:24285665

Yang, Xiaochun; Wang, Yutang

2013-01-01

249

An ultrastructural study of the mature spermatozoid of the fern Asplenium trichomanes L. subsp. trichomanes  

Microsoft Academic Search

Asplenium trichomanes L. subsp. trichomanes spermatozoids are spirals of about five turns. Keels link the elements of the microtubular ribbon with the plates of the lamellar\\u000a layer (LL) which are uninterrupted, parallel and curved with an inner angle of about 150. Electron-opaque filaments connect\\u000a the microtubules of the multilayered structure (MLS) and the osmiophilic crest, the LL and the MLS-associated

P. Gori; Simonetta Muccifora; Sheridan L. Woo; Lorenza M. Bellani

1997-01-01

250

MglA Regulates Francisella tularensis subsp. novicida (Francisella novicida) Response to Starvation and Oxidative Stress  

Microsoft Academic Search

MglA is a transcriptional regulator of genes that contribute to the virulence of Francisella tularensis, a highly infectious pathogen and the causative agent of tularemia. This study used a label-free shotgun proteomics method to determine the F. tularensis subsp. novicida (F. novicida) proteins that are regulated by MglA. The differences in relative protein amounts between wild-type F. novicida and the

Tina Guina; Dragan Radulovic; Arya J. Bahrami; Diana L. Bolton; Laurence Rohmer; Kendan A. Jones-Isaac; Jinzy Chen; Larry A. Gallagher; Byron Gallis; Soyoung Ryu; Greg K. Taylor; Mitchell J. Brittnacher; Colin Manoil; David R. Goodlett

2007-01-01

251

Detection of Mycobacterium avium subsp. paratuberculosis in tissue samples of cattle and buffaloes  

Microsoft Academic Search

Tissue samples were collected at random from cattle (Bos taurus) and buffalo (Bubalus bubalis) from an abattoir of the district of Lahore and were analyzed for the presence of Mycobacterium avium subsp. paratuberculosis and Mycobacterium bovis through acid-fast staining and polymerase chain reaction (PCR). Body condition of animals and diarrhea were recorded. Most\\u000a of the animals were emaciated. Diarrhea was

Farhan Anwar Khan; Zafar Iqbal Chaudhry; Muhammad Ijaz Ali; Shahid Khan; Naima Mumtaz; Ijaz Ahmad

2010-01-01

252

Isolation, Characterization, and Identification of Bacteria Associated with the Zinc Hyperaccumulator Thlaspi caerulescens subsp. Calaminaria  

Microsoft Academic Search

We investigated bacterial populations associated with the Zn hyperaccumulator Thlaspi caerulescens subsp. calaminaria grown in a soil collected from an abandoned Zn-Pb mine and smelter in Plombires, Belgium. The bacterial population of the nonrhizospheric soil consisted of typical soil bacteria, some exhibiting multiple heavy-metal resistance characteristics that often are associated with polluted substrates: 7.8% and 4% of the population survived

C. Lodewyckx; M. Mergeay; J. Vangronsveld; H. Clijsters; D. Van Der Lelie

2002-01-01

253

Citrate Cycle Intermediates in the Metabolism of Aspartate and Lactate by Propionibacterium freudenreichii subsp. shermanii.  

PubMed

Propionibacterium freudenreichii subsp. shermanii metabolized 7 mol of aspartate to 6 mol of succinate, 4 mol of CO(2), and 7 mol of ammonia. When lactate, sparged with 100% CO(2), was fermented at pH 5.5, unexpectedly high ratios of propionate to acetate were obtained (i.e., 3.2 to 3.8:1). Citrate cycle intermediates may be involved in these fermentations. PMID:16347477

Crow, V L

1987-10-01

254

Genetic and biochemical characterization of exopolysaccharide biosynthesis by Lactobacillus delbrueckii subsp. bulgaricus  

Microsoft Academic Search

Lactobacillus delbrueckii subsp. bulgaricus produces exopolysaccharides (EPSs), which play a role in the rheological properties of fermented food products. Lb. bulgaricus Lfi5 produces a high-molecular-weight EPS composed of galactose, glucose, and rhamnose in the molar ratio 5:1:1. An 18-kb DNA region containing 14 genes, designated epsA to epsN, was isolated by genomic DNA library screening and inverted PCR. The predicted

Gilbert Thierry Lamothe; Laure Jolly; Beat Mollet; Francesca Stingele

2002-01-01

255

Complete Genome Sequence of Type Strain Pasteurella multocida subsp. multocida ATCC 43137.  

PubMed

Soft-tissue infection by Pasteurella multocida in humans is usually associated with a dog- or cat-related injury, and these infections can become aggressive. We sequenced the type strain P.multocida subsp. multocida ATCC 43137 into a single closed chromosome consisting of 2,271,840 bp (40.4% G+C content), which is currently available in the NCBI GenBank under the accession number CP008918. PMID:25342682

Davenport, K W; Daligault, H E; Minogue, T D; Bishop-Lilly, K A; Bruce, D C; Chain, P S; Coyne, S R; Frey, K G; Jaissle, J; Koroleva, G I; Ladner, J T; Lo, C C; Palacios, G F; Redden, C L; Scholz, M B; Teshima, H; Johnson, S L

2014-01-01

256

Proximate composition and technological properties of fresh blackthorn ( Prunus spinosa L. subsp dasyphylla (Schur.)) fruits  

Microsoft Academic Search

In this study, the chemical and physical properties of blackthorn (Prunus spinosa subsp. dasyphlla (Schur.)) fruits growing wild in Konya province were determined. Proximate analysis such as dry matter, crude oil, crude protein, crude fibre, crude energy, ash, water-soluble and alcohol-soluble extract, pH and acid and mineral contents were established in this work. Al, B, Ca, K, Mg, Na, P

Derya Arslan; Musa zcan

2005-01-01

257

Ingestion and Adsorption of Bacillus thuringiensis subsp. israelensis by Gammarus lacustris in the Laboratory  

PubMed Central

Several groups of Gammarus lacustris adults were exposed to solutions containing 0.5 and 5.0 mg of Bacillus thuringiensis subsp. israelensis per liter for 1- or 24-h periods by using traditional static bioassay exposure procedures. During a postexposure holding period, fecal pellets were removed and plated on tryptic soy agar to determine B. thuringiensis subsp. israelensis spore content. The experiments verified that traditional exposure procedures assure ingestion of B. thuringiensis subsp. israelensis spores and provided a mean dose estimate of 1,948 spores ingested per test animal with a 95% confidence interval ranging from 891 to 4,296 (1-h exposure, 5.0 mg/liter). It was also found that dose level is highly dependent upon both exposure duration and concentration and that relatively short exposures can result in a relatively long-term retention of spores postexposure (?30 days). Body burden experiments established that large numbers of spores adsorb to the bodies of test animals during exposure and may in part explain the long-term retention of spores in the test system postexposure. These results imply that in field applications of microbial control agents, toxicologically unaffected but exposed organisms might transport the agent to untreated sites, expanding the effective treatment area and the number of organisms exposed. PMID:16347242

Brazner, John C.; Anderson, Richard L.

1986-01-01

258

Ingestion and Adsorption of Bacillus thuringiensis subsp. israelensis by Gammarus lacustris in the Laboratory.  

PubMed

Several groups of Gammarus lacustris adults were exposed to solutions containing 0.5 and 5.0 mg of Bacillus thuringiensis subsp. israelensis per liter for 1- or 24-h periods by using traditional static bioassay exposure procedures. During a postexposure holding period, fecal pellets were removed and plated on tryptic soy agar to determine B. thuringiensis subsp. israelensis spore content. The experiments verified that traditional exposure procedures assure ingestion of B. thuringiensis subsp. israelensis spores and provided a mean dose estimate of 1,948 spores ingested per test animal with a 95% confidence interval ranging from 891 to 4,296 (1-h exposure, 5.0 mg/liter). It was also found that dose level is highly dependent upon both exposure duration and concentration and that relatively short exposures can result in a relatively long-term retention of spores postexposure (>/=30 days). Body burden experiments established that large numbers of spores adsorb to the bodies of test animals during exposure and may in part explain the long-term retention of spores in the test system postexposure. These results imply that in field applications of microbial control agents, toxicologically unaffected but exposed organisms might transport the agent to untreated sites, expanding the effective treatment area and the number of organisms exposed. PMID:16347242

Brazner, J C; Anderson, R L

1986-12-01

259

Genetic Variability and Population Structure of Disanthus cercidifolius subsp. longipes (Hamamelidaceae) Based on AFLP Analysis.  

PubMed

Disanthus cercidifolius subsp. longipes is an endangered species in China. Genetic diversity and structure analysis of this species was investigated using amplified fragments length polymorphism (AFLP) fingerprinting. Nei's gene diversity ranged from 0.1290 to 0.1394. The AMOVA indicated that 75.06% of variation was distributed within populations, while the between-group component 5.04% was smaller than the between populations-within-group component 19.90%. Significant genetic differentiation was detected between populations. Genetic and geographical distances were not correlated. PCA and genetic structure analysis showed that populations from East China were together with those of the Nanling Range. These patterns of genetic diversity and levels of genetic variation may be the result of D. c. subsp. longipes restricted to several isolated habitats and "excess flowers production, but little fruit set". It is necessary to protect all existing populations of D. c. subsp. longipes in order to preserve as much genetic variation as possible. PMID:25250583

Yu, Yi; Fan, Qiang; Shen, Rujiang; Guo, Wei; Jin, Jianhua; Cui, Dafang; Liao, Wenbo

2014-01-01

260

Microencapsulation of Bifidobacterium animalis subsp. lactis and Lactobacillus acidophilus in cocoa butter using spray chilling technology  

PubMed Central

In the present study, the cells of Bifidobacterium animalis subsp. lactis (BI-01) and Lactobacillus acidophilus (LAC-04) were encapsulated in cocoa butter using spray-chilling technology. Survival assays were conducted to evaluate the resistance of the probiotics to the spray-chilling process, their resistance to the simulated gastric and intestinal fluids (SGF and SIF), and their stability during 90 days of storage. The viability of the cells was not affected by microencapsulation. The free and encapsulated cells of B. animalis subsp. lactis were resistant to both SGF and SIF. The micro-encapsulated cells of L. acidophilus were more resistant to SGF and SIF than the free cells; the viability of the encapsulated cells was enhanced by 67%, while the free cells reached the detection limit of the method (103 CFU/g). The encapsulated probiotics were unstable when they were stored at 20 C. The population of encapsulated L. acidophilus decreased drastically when they were stored at 7 C; only 20% of cells were viable after 90 days of storage. The percentage of viable cells of the encapsulated B. animalis subsp.lactis, however, was 72% after the same period of storage. Promising results were obtained when the microparticles were stored at ?18 C; the freeze granted 90 days of shelf life to the encapsulated cells. These results suggest that the spray-chilling process using cocoa butter as carrier protects L. acidophilus from gastrointestinal fluids. However, the viability of the cells during storage must be improved. PMID:24516445

Pedroso, D.L.; Dogenski, M.; Thomazini, M.; Heinemann, R.J.B.; Favaro-Trindade, C.S.

2013-01-01

261

Survival and Dormancy of Mycobacterium avium subsp. paratuberculosis in the Environment  

PubMed Central

The survival of Mycobacterium avium subsp. paratuberculosis was studied by culture of fecal material sampled at intervals for up to 117 weeks from soil and grass in pasture plots and boxes. Survival for up to 55 weeks was observed in a dry fully shaded environment, with much shorter survival times in unshaded locations. Moisture and application of lime to soil did not affect survival. UV radiation was an unlikely factor, but infrared wavelengths leading to diurnal temperature flux may be the significant detrimental component that is correlated with lack of shade. The organism survived for up to 24 weeks on grass that germinated through infected fecal material applied to the soil surface in completely shaded boxes and for up to 9 weeks on grass in 70% shade. The observed patterns of recovery in three of four experiments and changes in viable counts were indicative of dormancy, a hitherto unreported property of this taxon. A dps-like genetic element and relA, which are involved in dormancy responses in other mycobacteria, are present in the M. avium subsp. paratuberculosis genome sequence, providing indirect evidence for the existence of physiological mechanisms enabling dormancy. However, survival of M. avium subsp. paratuberculosis in the environment is finite, consistent with its taxonomic description as an obligate parasite of animals. PMID:15128561

Whittington, Richard J.; Marshall, D. Jeff; Nicholls, Paul J.; Marsh, Ian B.; Reddacliff, Leslie A.

2004-01-01

262

Lactobacillus delbrueckii subsp. bulgaricus CRL 454 cleaves allergenic peptides of ?-lactoglobulin.  

PubMed

Whey, a cheese by-product used as a food additive, is produced worldwide at 40.7 million tons per year. ?-Lactoglobulin (BLG), the main whey protein, is poorly digested and is highly allergenic. We aimed to study the contribution of Lactobacillus delbrueckii subsp. bulgaricus CRL 454 to BLG digestion and to analyse its ability to degrade the main allergenic sequences of this protein. Pre-hydrolysis of BLG by L. delbrueckii subsp. bulgaricus CRL 454 increases digestion of BLG assayed by an in vitro simulated gastrointestinal system. Moreover, peptides from hydrolysis of the allergenic sequences V41-K60, Y102-R124, C121-L140 and L149-I162 were found when BLG was hydrolysed by this strain. Interestingly, peptides possessing antioxidant, ACE inhibitory, antimicrobial and immuno-modulating properties were found in BLG degraded by both the Lactobacillus strain and digestive enzymes. To conclude, pre-hydrolysis of BLG by L. delbrueckii subsp. bulgaricus CRL 454 has a positive effect on BLG digestion and could diminish allergenic reactions. PMID:25306364

Pescuma, Micaela; Hbert, Elvira M; Haertl, Thomas; Chobert, Jean-Marc; Mozzi, Fernanda; Font de Valdez, Graciela

2015-03-01

263

New Type of Antimicrobial Protein Produced by the Plant Pathogen Clavibacter michiganensis subsp. michiganensis  

PubMed Central

It has previously been shown that the tomato pathogen Clavibacter michiganensis subsp. michiganensis secretes a 14-kDa protein, C. michiganensis subsp. michiganensis AMP-I (CmmAMP-I), that inhibits growth of Clavibacter michiganensis subsp. sepedonicus, the causal agent of bacterial ring rot of potato. Using sequences obtained from tryptic fragments, we have identified the gene encoding CmmAMP-I and we have recombinantly produced the protein with an N-terminal intein tag. The gene sequence showed that CmmAMP-I contains a typical N-terminal signal peptide for Sec-dependent secretion. The recombinant protein was highly active, with 50% growth inhibition (IC50) of approximately 10 pmol, but was not toxic to potato leaves or tubers. CmmAMP-I does not resemble any known protein and thus represents a completely new type of bacteriocin. Due to its high antimicrobial activity and its very narrow inhibitory spectrum, CmmAMP-1 may be of interest in combating potato ring rot disease. PMID:23851100

Liu, Zhanliang; Ma, Ping; Holtsmark, Ingrid; Skaugen, Morten; Eijsink, Vincent G. H.

2013-01-01

264

Antigenic and Genetic Characterization of Lipoprotein LppQ from Mycoplasma mycoides subsp. mycoides SC  

PubMed Central

Lipoprotein LppQ, a predominant 48-kDa antigen, and its corresponding gene, lppQ, were characterized in Mycoplasma mycoides subsp. mycoides SC, the etiological agent of contagious bovine pleuropneumonia. The lppQ gene is specific to M. mycoides subsp. mycoides SC and was found in the type strain and in field strains isolated in Europe, Africa, and Australia, as well as in vaccinal strains. LppQ is encoded as a precursor with a consensus sequence for prokaryotic signal peptidase II and a lipid attachment site. The leader sequence shows significant prominent transmembrane helix structure with a predicted outside-to-inside helix formation capacity. The N-terminal domain of the mature LppQ was shown to be surface exposed. It induced a strong, specific, early, and persistent immune response in naturally and experimentally infected animals. The C-terminal domain of LppQ possesses an integral membrane structure built up of repeated units, rich in hydrophobic and aromatic amino acids, which have a pore formation potential. A recombinant peptide representing the N-terminal domain of LppQ was obtained by site-directed mutagenesis of nine Mycoplasma-specific TGA (Trp) codons into universal TGG (Trp) codons and expression in Escherichia coli hosts. It was used for serodetection of cattle infected with M. mycoides subsp. mycoides SC, in which it was detected postinfection for significantly longer than conventional serological test reactions. PMID:10882657

Abdo, El-Mostafa; Nicolet, Jacques; Frey, Joachim

2000-01-01

265

Interactions between Bacillus thuringiensis subsp. israelensis and Fathead Minnows, Pimephales promelas Rafinesque, under Laboratory Conditions  

PubMed Central

Interactions between Bacillus thuringiensis subsp. israelensis and fathead minnows, Pimephales promelas, were studied in laboratory exposures to two commercial formulations, Vectobac-G and Mosquito Attack. Mortality among fatheads exposed to 2.0 106 to 6.5 106 CFU/ml with both formulations was attributed to severe dissolved oxygen depletion due to formulation ingredients rather than to direct toxicity from the parasporal crystal. No adverse effects were observed at 6.4 105 CFU/ml and below. Fathead minnows rapidly accumulated high numbers of spores with 1 h of exposure to 2.2 105 CFU of Mosquito Attack per ml, producing whole-body counts of 4.0 106 CFU per fish. Comparison of counts on gastrointestinal tract samples and whole-body samples and high numbers of spores in feces indicated that ingestion was the major route of exposure. B. thuringiensis subsp. israelensis spore counts decreased rapidly after transfer of fish to clean water, with a drop of over 3 orders of magnitude in 1 day. Spores were rarely detected in fish after 8 days but were detectable in feces for over 2 weeks. These findings suggest that fish could influence the dissemination of B. thuringiensis subsp. israelensis, and possibly other microbial agents, in the aquatic environment. PMID:16348271

Snarski, Virginia M.

1990-01-01

266

Genetic Variability and Population Structure of Disanthus cercidifolius subsp. longipes (Hamamelidaceae) Based on AFLP Analysis  

PubMed Central

Disanthus cercidifolius subsp. longipes is an endangered species in China. Genetic diversity and structure analysis of this species was investigated using amplified fragments length polymorphism (AFLP) fingerprinting. Nei's gene diversity ranged from 0.1290 to 0.1394. The AMOVA indicated that 75.06% of variation was distributed within populations, while the between-group component 5.04% was smaller than the between populations-within-group component 19.90%. Significant genetic differentiation was detected between populations. Genetic and geographical distances were not correlated. PCA and genetic structure analysis showed that populations from East China were together with those of the Nanling Range. These patterns of genetic diversity and levels of genetic variation may be the result of D. c. subsp. longipes restricted to several isolated habitats and excess flowers production, but little fruit set. It is necessary to protect all existing populations of D. c. subsp. longipes in order to preserve as much genetic variation as possible. PMID:25250583

Yu, Yi; Fan, Qiang; Shen, Rujiang; Guo, Wei; Jin, Jianhua; Cui, Dafang; Liao, Wenbo

2014-01-01

267

Expression and characterization of the periplasmic cobalamin-binding protein of Photobacterium damselae subsp. piscicida.  

PubMed

Abstract Cobalamin (vitamin B(12)) is an essential cofactor in a variety of enzymatic reactions and most prokaryotes contain transport systems to import vitamin B(12). A gene coding for a periplasmic cobalamin-binding protein of Photobacterium damselae subsp. piscicida was identified by in silico analysis of sequences from a genomic library. The open reading frame was composed of 834 bp encoding a protein of 277 amino acids. The protein showed 61% identity with the vitamin B(12)-binding protein precursor of P. profundum, 53% identity with the corresponding protein of Vibrio parahaemolyticus and 43% identity with the periplasmic binding protein BtuF of Escherichia coli. The expression of the native protein was investigated in P. damselae subsp. piscicida, but BtuF was weakly expressed under normal conditions. To characterize the BtuF of P. damselae subsp. piscicida, the recombinant protein was expressed with a C-terminal His(6)-tag and purified; the molecular weight was estimated to be approximately 30 kDa. The protein does not contain any free thiol group, consistent with the view that the two cysteine residues are involved in a disulphide bond. The purified BtuF binds cyanocobalamin with an affinity constant of 6 +/- 2 microm. PMID:19490395

Boiani, R; Andreoni, F; Serafini, G; Bianconi, I; Pierleoni, R; Dominici, S; Gorini, F; Magnani, M

2009-09-01

268

Effect of Soil Slope on the Appearance of Mycobacterium avium subsp. paratuberculosis in Water Running off Grassland Soil after Application of Contaminated Slurry  

PubMed Central

The study assessed the effect of soil slope on Mycobacterium avium subsp. paratuberculosis transport into rainwater runoff from agricultural soil after application of M. avium subsp. paratuberculosis-contaminated slurry. Under field conditions, 24 plots of undisturbed loamy soil 1 by 2 m2 were placed on platforms. Twelve plots were used for water runoff: 6 plots at a 3% slope and 6 plots at a 15% slope. Half of the plots of each slope were treated with M. avium subsp. paratuberculosis-contaminated slurry, and half were not treated. Using the same experimental design, 12 plots were established for soil sampling on a monthly basis using the same spiked slurry application and soil slopes. Runoff following natural rainfall was collected and analyzed for M. avium subsp. paratuberculosis, coliforms, and turbidity. M. avium subsp. paratuberculosis was detected in runoff from all plots treated with contaminated slurry and one control plot. A higher slope (15%) increased the likelihood of M. avium subsp. paratuberculosis detection but did not affect the likelihood of finding coliforms. Daily rainfall increased the likelihood that runoff would have coliforms and the coliform concentration, but it decreased the M. avium subsp. paratuberculosis concentration in the runoff. When there was no runoff, rain was associated with increased M. avium subsp. paratuberculosis concentrations. Coliform counts in runoff were related to runoff turbidity. M. avium subsp. paratuberculosis presence/absence, however, was related to turbidity. Study duration decreased bacterial detection and concentration. These findings demonstrate the high likelihood that M. avium subsp. paratuberculosis in slurry spread on pastures will contaminate water runoff, particularly during seasons with high rainfall. M. avium subsp. paratuberculosis contamination of water has potential consequences for both animal and human health. PMID:23542616

Alfaro, M.; Salazar, F.; Troncoso, E.; Mitchell, R. M.; Ramirez, L.; Naguil, A.; Zamorano, P.; Collins, M. T.

2013-01-01

269

Novel Feature of Mycobacterium avium subsp. paratuberculosis, Highlighted by Characterization of the Heparin-Binding Hemagglutinin Adhesin  

PubMed Central

Mycobacterium avium subsp. paratuberculosis comprises two genotypically defined groups, known as the cattle (C) and sheep (S) groups. Recent studies have reported phenotypic differences between M. avium subsp. paratuberculosis groups C and S, including growth rates, infectivity for macrophages, and iron metabolism. In this study, we investigated the genotypes and biological properties of the virulence factor heparin-binding hemagglutinin adhesin (HBHA) for both groups. In Mycobacterium tuberculosis, HBHA is a major adhesin involved in mycobacterium-host interactions and extrapulmonary dissemination of infection. To investigate HBHA in M. avium subsp. paratuberculosis, we studied hbhA polymorphisms by fragment analysis using the GeneMapper technology across a large collection of isolates genotyped by mycobacterial interspersed repetitive-unitvariable-number tandem-repeat (MIRU-VNTR) and IS900 restriction fragment length polymorphism (RFLP-IS900) analyses. Furthermore, we analyzed the structure-function relationships of recombinant HBHA proteins of types C and S by heparin-Sepharose chromatography and surface plasmon resonance (SPR) analyses. In silico analysis revealed two forms of HBHA, corresponding to the prototype genomes for the C and S types of M. avium subsp. paratuberculosis. This observation was confirmed using GeneMapper on 85 M. avium subsp. paratuberculosis strains, including 67 strains of type C and 18 strains of type S. We found that HBHAs from all type C strains contain a short C-terminal domain, while those of type S present a long C-terminal domain, similar to that produced by Mycobacterium avium subsp. avium. The purification of recombinant HBHA from M. avium subsp. paratuberculosis of both types by heparin-Sepharose chromatography highlighted a correlation between their affinities for heparin and the lengths of their C-terminal domains, which was confirmed by SPR analysis. Thus, types C and S of M. avium subsp. paratuberculosis may be distinguished by the types of HBHA they produce, which differ in size and adherence properties, thereby providing new evidence that strengthens the genotypic differences between the C and S types of M. avium subsp. paratuberculosis. PMID:23974028

Lefrancois, Louise H.; Bodier, Christelle C.; Cochard, Thierry; Canepa, Sylvie; Raze, Dominique; Lanotte, Philippe; Sevilla, Iker A.; Stevenson, Karen; Behr, Marcel A.; Locht, Camille

2013-01-01

270

Novel feature of Mycobacterium avium subsp. paratuberculosis, highlighted by characterization of the heparin-binding hemagglutinin adhesin.  

PubMed

Mycobacterium avium subsp. paratuberculosis comprises two genotypically defined groups, known as the cattle (C) and sheep (S) groups. Recent studies have reported phenotypic differences between M. avium subsp. paratuberculosis groups C and S, including growth rates, infectivity for macrophages, and iron metabolism. In this study, we investigated the genotypes and biological properties of the virulence factor heparin-binding hemagglutinin adhesin (HBHA) for both groups. In Mycobacterium tuberculosis, HBHA is a major adhesin involved in mycobacterium-host interactions and extrapulmonary dissemination of infection. To investigate HBHA in M. avium subsp. paratuberculosis, we studied hbhA polymorphisms by fragment analysis using the GeneMapper technology across a large collection of isolates genotyped by mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) and IS900 restriction fragment length polymorphism (RFLP-IS900) analyses. Furthermore, we analyzed the structure-function relationships of recombinant HBHA proteins of types C and S by heparin-Sepharose chromatography and surface plasmon resonance (SPR) analyses. In silico analysis revealed two forms of HBHA, corresponding to the prototype genomes for the C and S types of M. avium subsp. paratuberculosis. This observation was confirmed using GeneMapper on 85 M. avium subsp. paratuberculosis strains, including 67 strains of type C and 18 strains of type S. We found that HBHAs from all type C strains contain a short C-terminal domain, while those of type S present a long C-terminal domain, similar to that produced by Mycobacterium avium subsp. avium. The purification of recombinant HBHA from M. avium subsp. paratuberculosis of both types by heparin-Sepharose chromatography highlighted a correlation between their affinities for heparin and the lengths of their C-terminal domains, which was confirmed by SPR analysis. Thus, types C and S of M. avium subsp. paratuberculosis may be distinguished by the types of HBHA they produce, which differ in size and adherence properties, thereby providing new evidence that strengthens the genotypic differences between the C and S types of M. avium subsp. paratuberculosis. PMID:23974028

Lefrancois, Louise H; Bodier, Christelle C; Cochard, Thierry; Canepa, Sylvie; Raze, Dominique; Lanotte, Philippe; Sevilla, Iker A; Stevenson, Karen; Behr, Marcel A; Locht, Camille; Biet, Franck

2013-11-01

271

Prevalence and Acquisition of the Genes for Zoocin A and Zoocin A Resistance in Streptococcus equi subsp. zooepidemicus  

PubMed Central

Zoocin A is a streptococcolytic enzyme produced by Streptococcus equi subsp. zooepidemicus strain 4881. The zoocin A gene (zooA) and the gene specifying resistance to zoocin A (zif) are adjacent on the chromosome and are divergently transcribed. Twenty-four S. equi subsp. zooepidemicus strains were analyzed to determine the genetic difference between three previously characterized as zoocin A producers (strains 4881, 9g and 9h) and the twenty-one non-producers. LT-PCR and Southern hybridization studies revealed that none of the non-producer strains possessed zooA or zif. RAPD and PFGE showed that the 24 strains were a genetically diverse population with 8 RAPD profiles. S. equi subsp. zooepidemicus strains 9g and 9h appeared genetically identical to each other, but quite different from 4881. Sequences derived from 4881 and 9g showed that zooA and zif were integrated into the chromosome adjacent to the gene flaR. A comparison of these sequences with the genome sequences of S. equi subsp. zooepidemicus strains H70 and MGCS10565 and S. equi subsp. equi strain 4047 suggests that flaR flanks a region of genome plasticity in this species. PMID:19357799

O'Rourke, Anna-Lee D.; Simmonds, Robin S.; Gargis, Amy S.; Sloan, Gary L.

2009-01-01

272

recA is required in the induction of pectin lyase and carotovoricin in Erwinia carotovora subsp. carotovora.  

PubMed Central

Pectin lyase (PNL) and the bacteriocin carotovoricin (CTV) were induced in Erwinia carotovora subsp. carotovora 71 by the DNA-damaging agents mitomycin C, nalidixic acid, and UV light. To determine whether the recA product was involved in the expression of these damage-inducible phenotypes, we cloned the E. carotovora subsp. carotovora recA+ gene, inactivated it by Tn5 insertion, and constructed an E. carotovora subsp. carotovora recA::Tn5 strain by gene replacement via homologous recombination. The RecA- strain was more sensitive to methyl methanesulfonate, nitroquinoline oxide, and UV light than its RecA+ parent. The recA mutation did not affect the production of pectate lyase, polygalacturonase, cellulase, and protease or the ability to cause soft rot of potato tubers. With this mutant, unlike with the RecA+ parent strain, PNL and CTV were not induced by mitomycin C or detected in potato tuber tissue. The RecA+ phenotype, including the inducibility of PNL and CTV, could, however, be restored in the mutant in trans by the recA+ gene from either E. carotovora subsp. carotovora or Escherichia coli. We conclude that, in E. carotovora subsp. carotovora, the recA product is required in the induction of PNL and CTV. Images PMID:4044526

Zink, R T; Engwall, J K; McEvoy, J L; Chatterjee, A K

1985-01-01

273

"Mycobacterium avium subsp. hominissuis" in neck lymph nodes of children and their environment examined by culture and triplex quantitative real-time PCR.  

PubMed

"Mycobacterium avium subsp. hominissuis" often causes cervical lymphadenitis in children; its prompt and accurate identification enables adequate therapy, tracing, and prevention. The aims of this study were to determine the causative agent of lymphadenitis using culture, PCR, and triplex quantitative real-time PCR (qPCR) methods with DNA directly isolated from tissue, as well as to identify possible sources of infection from the environment. We confirmed the diagnoses by detecting M. avium subsp. hominissuis using qPCR with DNA directly isolated from lymph node biopsy specimens of two patients. In order to trace the source of infection from the environment, a method of DNA isolation from soil and other environmental samples, such as dust, cobwebs, and compost, was developed. The triplex qPCR examination revealed the presence of M. avium subsp. hominissuis in a high proportion of the environmental samples (42.8% in the first patient's house and 47.6% in the second patient's house). Both patients were also exposed to M. avium subsp. avium, which was present due to the breeding of infected domestic hens. The high infectious dose of M. avium subsp. hominissuis or the increased susceptibility of humans to M. avium subsp. hominissuis compared to M. avium subsp. avium could be the reason why the children were infected with M. avium subsp. hominissuis. PMID:21084514

Kaevska, Marija; Slana, Iva; Kralik, Petr; Reischl, Udo; Orosova, Jaroslava; Holcikova, Alena; Pavlik, Ivo

2011-01-01

274

"Mycobacterium avium subsp. hominissuis" in Neck Lymph Nodes of Children and their Environment Examined by Culture and Triplex Quantitative Real-Time PCR ?  

PubMed Central

Mycobacterium avium subsp. hominissuis often causes cervical lymphadenitis in children; its prompt and accurate identification enables adequate therapy, tracing, and prevention. The aims of this study were to determine the causative agent of lymphadenitis using culture, PCR, and triplex quantitative real-time PCR (qPCR) methods with DNA directly isolated from tissue, as well as to identify possible sources of infection from the environment. We confirmed the diagnoses by detecting M. avium subsp. hominissuis using qPCR with DNA directly isolated from lymph node biopsy specimens of two patients. In order to trace the source of infection from the environment, a method of DNA isolation from soil and other environmental samples, such as dust, cobwebs, and compost, was developed. The triplex qPCR examination revealed the presence of M. avium subsp. hominissuis in a high proportion of the environmental samples (42.8% in the first patient's house and 47.6% in the second patient's house). Both patients were also exposed to M. avium subsp. avium, which was present due to the breeding of infected domestic hens. The high infectious dose of M. avium subsp. hominissuis or the increased susceptibility of humans to M. avium subsp. hominissuis compared to M. avium subsp. avium could be the reason why the children were infected with M. avium subsp. hominissuis. PMID:21084514

Kaevska, Marija; Slana, Iva; Kralik, Petr; Reischl, Udo; Orosova, Jaroslava; Holcikova, Alena; Pavlik, Ivo

2011-01-01

275

La presenza di colesterolo nella frazione sterolica dell'olio dei semi di Solanum nigrum L. subsp. nigrum e Solanum dulcamara L  

Microsoft Academic Search

The presence of cholesterol in the sterolic fraction in the oil of the seeds of Solanum nigrum L. subsp. nigrum and Solanum dulcamara L.The sterol fraction of oil in Solanum nigrum L. subsp. nigrum and Solanum dulcamara L. seeds has been analysed by GLC. The amounts of cholesterol we have found are 8% and 23% respectively, in relation to the

Paola Gastaldo; Paola Profumo; Enrico Tiscornia; Maria Angela Pagano

1977-01-01

276

Enhanced ozone strongly reduces carbon sink strength of adult beech (Fagus sylvatica)--resume from the free-air fumigation study at Kranzberg Forest.  

PubMed

Ground-level ozone (O(3)) has gained awareness as an agent of climate change. In this respect, key results are comprehended from a unique 8-year free-air O(3)-fumigation experiment, conducted on adult beech (Fagus sylvatica) at Kranzberg Forest (Germany). A novel canopy O(3) exposure methodology was employed that allowed whole-tree assessment in situ under twice-ambient O(3) levels. Elevated O(3) significantly weakened the C sink strength of the tree-soil system as evidenced by lowered photosynthesis and 44% reduction in whole-stem growth, but increased soil respiration. Associated effects in leaves and roots at the gene, cell and organ level varied from year to year, with drought being a crucial determinant of O(3) responsiveness. Regarding adult individuals of a late-successional tree species, empirical proof is provided first time in relation to recent modelling predictions that enhanced ground-level O(3) can substantially mitigate the C sequestration of forests in view of climate change. PMID:20570421

Matyssek, R; Wieser, G; Ceulemans, R; Rennenberg, H; Pretzsch, H; Haberer, K; Lw, M; Nunn, A J; Werner, H; Wipfler, P; Osswald, W; Nikolova, P; Hanke, D E; Kraigher, H; Tausz, M; Bahnweg, G; Kitao, M; Dieler, J; Sandermann, H; Herbinger, K; Grebenc, T; Blumenrther, M; Deckmyn, G; Grams, T E E; Heerdt, C; Leuchner, M; Fabian, P; Hberle, K-H

2010-08-01

277

Impact of elevated atmospheric O3 on the actinobacterial community structure and function in the rhizosphere of European beech (Fagus sylvatica L.)  

PubMed Central

Many bacteria belonging to the phylum of Actinobacteria are known as antagonists against phytpathogenic microbes. This study aimed to analyze the effect of ozone on the actinobacterial community of the rhizosphere of four years old European beech (Fagus sylvatica L.) trees during different time points of the vegetation period. Effects of ozone on the total community structure of Actinobacteria were studied based on the analysis of 16S rRNA gene amplicons. In addition effects of the ozone treatment on the diversity of potential biocontrol active Actionobacteria being able to produce antibiotics were characterized by using the type II polyketide synthases (PKS) genes as marker. Season as well as ozone treatments had a significant effect on parts of the actinobacterial rhizosphere community of European beech. However on the basis of the performed analysis, the diversity of Actinobacteria possessing type II PKS genes is neither affected by seasonal changes nor by the ozone treatments, indicating no influence of the investigated treatments on the biocontrol active part of the actinobacterial community. PMID:24575080

Haesler, Felix; Hagn, Alexandra; Engel, Marion; Schloter, Michael

2014-01-01

278

Detecting short spatial scale local adaptation and epistatic selection in climate-related candidate genes in European beech (Fagus sylvatica) populations.  

PubMed

Detecting signatures of selection in tree populations threatened by climate change is currently a major research priority. Here, we investigated the signature of local adaptation over a short spatial scale using 96 European beech (Fagus sylvatica L.) individuals originating from two pairs of populations on the northern and southern slopes of Mont Ventoux (south-eastern France). We performed both single and multilocus analysis of selection based on 53 climate-related candidate genes containing 546 SNPs. FST outlier methods at the SNP level revealed a weak signal of selection, with three marginally significant outliers in the northern populations. At the gene level, considering haplotypes as alleles, two additional marginally significant outliers were detected, one on each slope. To account for the uncertainty of haplotype inference, we averaged the Bayes factors over many possible phase reconstructions. Epistatic selection offers a realistic multilocus model of selection in natural populations. Here, we used a test suggested by Ohta based on the decomposition of the variance of linkage disequilibrium. Overall populations, 0.23% of the SNP pairs (haplotypes) showed evidence of epistatic selection, with nearly 80% of them being within genes. One of the between gene epistatic selection signals arose between an FST outlier and a nonsynonymous mutation in a drought response gene. Additionally, we identified haplotypes containing selectively advantageous allele combinations which were unique to high or low elevations and northern or southern populations. Several haplotypes contained nonsynonymous mutations situated in genes with known functional importance for adaptation to climatic factors. PMID:25156570

Csillry, Katalin; Lalage, Hadrien; Vendramin, Giovanni G; Gonzlez-Martnez, Santiago C; Fady, Bruno; Oddou-Muratorio, Sylvie

2014-10-01

279

DrsG from Streptococcus dysgalactiae subsp. equisimilis inhibits the antimicrobial peptide LL-37.  

PubMed

SIC and DRS are related proteins present in only 4 of the >200 Streptococcus pyogenes emm types. These proteins inhibit complement-mediated lysis and/or the activity of certain antimicrobial peptides (AMPs). A gene encoding a homologue of these proteins, herein called DrsG, has been identified in the related bacterium Streptococcus dysgalactiae subsp. equisimilis. Here we show that geographically dispersed isolates representing 14 of 50 emm types examined possess variants of drsG. However, not all isolates within the drsG-positive emm types possess the gene. Sequence comparisons also revealed a high degree of conservation in different S. dysgalactiae subsp. equisimilis emm types. To examine the biological activity of DrsG, recombinant versions of two major DrsG variants, DrsGS and DrsGL, were expressed and purified. Western blot analysis using antisera raised to these proteins demonstrated both variants to be expressed and secreted into culture supernatants. Unlike SIC, but similar to DRS, DrsG does not inhibit complement-mediated lysis. However, like both SIC and DRS, DrsG is a ligand of the cathelicidin LL-37 and is inhibitory to its bactericidal activity in in vitro assays. Conservation of prolines in the C-terminal region also suggests that these residues are important in the biology of this family of proteins. This is the first report demonstrating the activity of an AMP-inhibitory protein in S. dysgalactiae subsp. equisimilis and suggests that inhibition of AMP activity is the primary function of this family of proteins. The acquisition of the complement-inhibitory activity of SIC may reflect its continuing evolution. PMID:24664506

Smyth, Danielle; Cameron, Ainslie; Davies, Mark R; McNeilly, Celia; Hafner, Louise; Sriprakash, Kadaba S; McMillan, David J

2014-06-01

280

Phylogeography and seed dispersal in islands: the case of Rumex bucephalophorus subsp. canariensis (Polygonaceae)  

PubMed Central

Background and Aims Rumex bucephalophorus subsp. canariensis is an endemic taxon to Macaronesia with diaspore polymorphism. The origin and colonizing route of this taxon in Macaronesia was studied using molecular data and information on diaspore types. Methods Amplified fragment length polymorphism (AFLP) was used in 260 plants from 22 populations of R. bucephalophorus subsp. canariensis, four from the Madeiran archipelago and 18 from the Canary archipelago. Diaspore production was analysed in 950 plants from each population used for AFLP analysis. One hundred and one plants from the Madeiran archipelago and 375 plants from the Canary Islands were studied. For each plant the type of diaspore produced was recorded. Key Results Overall populations had low genetic diversity but they showed a geographical pattern of genetic diversity that was higher in the older eastern islands than in the younger western ones. Two types of dispersible diaspores were found: in the eastern Canary islands (Lanzarote, Fuerteventura and Gran Canaria), plants produced exclusively long-dispersible diaspores, whereas in the western Canary islands (Tenerife, La Gomera, El Hierro) and the Madeiran archipelago plants produced exclusively short-dispersible diaspores. Genetically, the studied populations fell into four main island groups: LanzaroteFuerteventura, Gran Canaria, TenerifeEl Hierro and La GomeraMadeira archipelago. Conclusions A Moroccan origin of R. bucephalophorus subsp. canariensis is hypothesized with a colonization route from the eastern to the western islands. In addition, at least one gene flow event from La Gomera to the Madeiran archipelago has taken place. During the colonization process the type of dispersible diaspore changed so that dispersability decreased in populations of the westernmost islands. PMID:23267005

Talavera, Maria; Navarro-Sampedro, Laura; Ortiz, Pedro L.; Arista, Montserrat

2013-01-01

281

Characterization of a New Bacteriocin, Carocin D, from Pectobacterium carotovorum subsp. carotovorum Pcc21?  

PubMed Central

Two different bacteriocins, carotovoricin and carocin S1, had been found in Pectobacterium carotovorum subsp. carotovorum, which causes soft-rot disease in diverse plants. Previously, we reported that the particular strain Pcc21, producing only one high-molecular-weight bacteriocin, carried a new antibacterial activity against the indicator strain Pcc3. Here, we report that this new antibacterial activity is due to a new bacteriocin produced by strain Pcc21 and named carocin D. Carocin D is encoded by the caroDK gene located in the genomic DNA together with the caroDI gene, which seems to encode an immunity protein. N-terminal amino acid sequences of purified carocin D were determined by Edman degradation. In comparison with the primary translation product of caroDK, it was found that 8 amino acids are missing at the N terminus. This finding proved that carocin D is synthesized as a precursor peptide and that 8 amino acids are removed from its N terminus during maturation. Carocin D has two putative translocation domains; the N-terminal and C-terminal domains are homologous to those of Escherichia coli colicin E3 and Pseudomonas aeruginosa S-type pyocin, respectively. When caroDK and caroDI genes were transformed into carocin D-sensitive bacteria such as Pcc3, the bacteria became resistant to this bacteriocin. Carocin D has one putative DNase domain at the extreme C terminus and showed DNase activity in vitro. This bacteriocin had slight tolerance to heat but not to proteases. The caroDK gene was present in only 5 of 54 strains of P. carotovorum subsp. carotovorum. These results indicate that carocin D is a third bacteriocin found in P. carotovorum subsp. carotovorum, and this bacteriocin can be readily expressed in carocin D-sensitive nonpathogenic bacteria, which may have high potential as a biological control agent in the field. PMID:20870796

Roh, Eunjung; Park, Tae-Ho; Kim, Myung-il; Lee, Seungdon; Ryu, Sangryeol; Oh, Chang-Sik; Rhee, Sangkee; Kim, Doo-Ho; Park, Beom-Seok; Heu, Sunggi

2010-01-01

282

Essential oil of Juniperus communis subsp. alpina (Suter) ?elak needles: chemical composition, antifungal activity and cytotoxicity.  

PubMed

Essential oils are known to possess antimicrobial activity against a wide spectrum of bacteria and fungi. In the present work the composition and the antifungal activity of the oils of Juniperus communis subsp. alpina (Suter) ?elak were evaluated. Moreover, the skin cytotoxicity, at concentrations showing significant antifungal activity, was also evaluated. The oils were isolated by hydrodistillation and analysed by gas chromatography and gas chromatography-mass spectrometry. Minimal inhibitory concentration (MIC) and minimal lethal concentration (MLC) were used to evaluate the antifungal activity of the oil against dermatophytes (Epidermophyton floccosum, Microsporum canis, M. gypseum, Trichophyton mentagrophytes, T. mentagrophytes var. interdigitale, T. rubrum, T. verrucosum), yeasts (Candida albicans, C. guillermondii, C. krusei, C. parapsilosis, C. tropicalis, Cryptococcus neoformans) and Aspergillus species (Aspergillus flavus, A. fumigatus, A. niger). Cytotoxicity was tested in HaCaT keratinocytes through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Essential oil of J. communis subsp. alpina needles was predominantly composed of monoterpene hydrocarbons (78.4%), with the main compounds being sabinene (26.2%), ?-pinene (12-9%) and limonene (10.4%). Results concerning the antifungal activity demonstrated the potential of needle oil against dermatophytes, particularly for Microsporum canis and Trichophyton rubrum with MIC and MLC of 0.32 ?L/mL. Furthermore, evaluation of cell viability showed no significant cytotoxicity in HaCaT keratinocytes at concentrations between 0.32 and 0.64 ?L/mL. These results show that it is possible to find appropriate doses of J. communis subsp. alpina oil with both antifungal activity and a very low detrimental effect on keratinocytes. PMID:22294341

Cabral, C; Francisco, V; Cavaleiro, C; Gonalves, M J; Cruz, M T; Sales, F; Batista, M T; Salgueiro, L

2012-09-01

283

Early Immune Markers Associated with Mycobacterium avium subsp. paratuberculosis Infection in a Neonatal Calf Model ?  

PubMed Central

The objective of this study was to observe early markers of cell-mediated immunity in nave calves infected with Mycobacterium avium subsp. paratuberculosis and how expression of these markers evolved over the 12-month period of infection. Groups for experimental infection included control (noninfected), oral (infected orally with M. avium subsp. paratuberculosis strain K-10), oral/DXM (pretreatment with dexamethasone before oral inoculation), intraperitoneal (i.p.) inoculation, and oral/M (oral inoculation with mucosal scrapings from a cow with clinical disease) groups. One of the earliest markers to emerge was antigen-specific gamma interferon (IFN-?). Only i.p. inoculated calves had detectable antigen-specific IFN-? responses at 7 days, with responses of the other infection groups becoming detectable at 90 and 120 days. All infection groups maintained robust IFN-? responses for the remainder of the study. At 1 month, calves in the oral and oral/M groups had higher antigen-stimulated interleukin-10 (IL-10) levels than calves in the other treatment groups, but IL-10 secretion declined by 12 months for all calves. T-cell activation markers such as CD25, CD26, CD45RO, and CD5 were significantly upregulated in infected calves compared to noninfected controls. Oral inoculation of calves resulted in significantly increased antigen-specific lymphocyte proliferation at 9 and 12 months, as well as inducible nitric oxide synthase (iNOS) secretion at 6 and 12 months. These results demonstrate that infection of nave calves with M. avium subsp. paratuberculosis invoked early immunologic responses characterized by robust antigen-specific IFN-? responses and induction of CD25 and CD45RO expression on T-cell subsets. These were followed by antigen-specific lymphocyte proliferation, iNOS secretion, and expression of CD26 and CD5bright markers in the latter part of the 12-month study. PMID:21228140

Stabel, J. R.; Robbe-Austerman, S.

2011-01-01

284

Persistence and Decontamination of Bacillus atrophaeus subsp. globigii Spores on Corroded Iron in a Model Drinking Water System?  

PubMed Central

Persistence of Bacillus atrophaeus subsp. globigii spores on corroded iron coupons in drinking water was studied using a biofilm annular reactor. Spores were inoculated at 106 CFU/ml in the dechlorinated reactor bulk water. The dechlorination allowed for observation of the effects of hydraulic shear and biofilm sloughing on persistence. Approximately 50% of the spores initially adhered to the corroded iron surface were not detected after 1 month. Addition of a stable 10 mg/liter free chlorine residual after 1 month led to a 2-log10 reduction of adhered B. atrophaeus subsp. globigii, but levels on the coupons quickly stabilized thereafter. Increasing the free chlorine concentration to 25 or 70 mg/liter had no additional effect on inactivation. B. atrophaeus subsp. globigii spores injected in the presence of a typical distribution system chlorine residual (?0.75 mg/liter) resulted in a steady reduction of adhered B. atrophaeus subsp. globigii over 1 month, but levels on the coupons eventually stabilized. Adding elevated chlorine levels (10, 25, and 70 mg/liter) after 1 month had no effect on the rate of inactivation. Decontamination with elevated free chlorine levels immediately after spore injection resulted in a 3-log10 reduction within 2 weeks, but the rate of inactivation leveled off afterward. This indicates that free chlorine did not reach portions of the corroded iron surface where B. atrophaeus subsp. globigii spores had adhered. B. atrophaeus subsp. globigii spores are capable of persisting for an extended time in the presence of high levels of free chlorine. PMID:17308186

Szabo, Jeffrey G.; Rice, Eugene W.; Bishop, Paul L.

2007-01-01

285

Transcriptome-Based Characterization of Interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus in Lactose-Grown Chemostat Cocultures  

PubMed Central

Mixed populations of Saccharomyces cerevisiae yeasts and lactic acid bacteria occur in many dairy, food, and beverage fermentations, but knowledge about their interactions is incomplete. In the present study, interactions between Saccharomyces cerevisiae and Lactobacillus delbrueckii subsp. bulgaricus, two microorganisms that co-occur in kefir fermentations, were studied during anaerobic growth on lactose. By combining physiological and transcriptome analysis of the two strains in the cocultures, five mechanisms of interaction were identified. (i) Lb. delbrueckii subsp. bulgaricus hydrolyzes lactose, which cannot be metabolized by S. cerevisiae, to galactose and glucose. Subsequently, galactose, which cannot be metabolized by Lb. delbrueckii subsp. bulgaricus, is excreted and provides a carbon source for yeast. (ii) In pure cultures, Lb. delbrueckii subsp. bulgaricus grows only in the presence of increased CO2 concentrations. In anaerobic mixed cultures, the yeast provides this CO2 via alcoholic fermentation. (iii) Analysis of amino acid consumption from the defined medium indicated that S. cerevisiae supplied alanine to the bacterium. (iv) A mild but significant low-iron response in the yeast transcriptome, identified by DNA microarray analysis, was consistent with the chelation of iron by the lactate produced by Lb. delbrueckii subsp. bulgaricus. (v) Transcriptome analysis of Lb. delbrueckii subsp. bulgaricus in mixed cultures showed an overrepresentation of transcripts involved in lipid metabolism, suggesting either a competition of the two microorganisms for fatty acids or a response to the ethanol produced by S. cerevisiae. This study demonstrates that chemostat-based transcriptome analysis is a powerful tool to investigate microbial interactions in mixed populations. PMID:23872557

Mendes, Filipa; Sieuwerts, Sander; de Hulster, Erik; Almering, Marinka J. H.; Luttik, Marijke A. H.; Pronk, Jack T.; Smid, Eddy J.; Bron, Peter A.

2013-01-01

286

Salmonella enterica Suppresses Pectobacterium carotovorum subsp. carotovorum Population and Soft Rot Progression by Acidifying the Microaerophilic Environment  

PubMed Central

ABSTRACT Although enteric human pathogens are usually studied in the context of their animal hosts, a significant portion of their life cycle occurs on plants. Plant disease alters the phyllosphere, leading to enhanced growth of human pathogens; however, the impact of human pathogens on phytopathogen biology and plant health is largely unknown. To characterize the interaction between human pathogens and phytobacterial pathogens in the phyllosphere, we examined the interactions between Pectobacterium carotovorum subsp. carotovorum and Salmonella enterica or Escherichia coli O157:H7 with regard to bacterial populations, soft rot progression, and changes in local pH. The presence of P. carotovorum subsp. carotovorum enhanced the growth of both S.enterica and E.coli O157:H7 on leaves. However, in a microaerophilic environment, S.enterica reduced P. carotovorum subsp. carotovorum populations and soft rot progression by moderating local environmental pH. Reduced soft rot was not due to S.enterica proteolytic activity. Limitations on P. carotovorum subsp. carotovorum growth, disease progression, and pH elevation were not observed on leaves coinoculated with E.coli O157:H7 or when leaves were coinoculated with S.enterica in an aerobic environment. S.enterica also severely undermined the relationship between the phytobacterial population and disease progression of a P. carotovorum subsp. carotovorum budB mutant defective in the 2,3-butanediol pathway for acid neutralization. Our results show that S.enterica and E.coli O157:H7 interact differently with the enteric phytobacterial pathogen P. carotovorum subsp. carotovorum. S.enterica inhibition of soft rot progression may conceal a rapidly growing human pathogen population. Whereas soft rotted produce can alert consumers to the possibility of food-borne pathogens, healthy-looking produce may entice consumption of contaminated vegetables. PMID:23404399

Kwan, Grace; Charkowski, Amy O.; Barak, Jeri D.

2013-01-01

287

A circular genetic map of Erwinia carotovora subsp. atroseptica 3-2  

SciTech Connect

A circular genetic map of Erwinia carotovora subsp. atroseptica 3-2 was constructed on the basis of the R471a plasmid and Tn5 and Tn9 using Hfr-like donors. Forty-six genes, including phytopathogenicity genes, were located on the basis of interrupted mating experiment results and analysis of coinheritance of markers on a map of 183 min in length. The similarity and differences of chromosomal genetic maps of Erwinia genus bacteria are discussed. 23 refs., 2 figs., 4 tabs.

Nikolaichik, E.A.; Pesnyakevich, A.G. [Belarussian State Univ., Minsk (Belarus)

1995-08-01

288

Complete Genome Sequence of the Ethanol-Producing Zymomonas mobilis subsp. mobilis Centrotype ATCC 29191  

PubMed Central

Zymomonas mobilis is an ethanologenic bacterium that has been studied for use in biofuel production. Of the sequenced Zymomonas strains, ATCC 29191 has been described as the phenotypic centrotype of Zymomonas mobilis subsp. mobilis, the taxon that harbors the highest ethanol-producing Z. mobilis strains. ATCC 29191 was isolated in Kinshasa, Congo, from palm wine fermentations. This strain is reported to be a robust levan producer, while in recent years it has been employed in studies addressing Z. mobilis respiration. Here we announce the finishing and annotation of the ATCC 29191 genome, which comprises one chromosome and three plasmids. PMID:23045486

Desiniotis, Andreas; Kouvelis, Vassili N.; Davenport, Karen; Bruce, David; Detter, Chris; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne A.; Woyke, Tanja; Kyrpides, Nikos C.; Typas, Milton A.

2012-01-01

289

Chemical Composition and Seasonal Variation of Hypericum hircinum L. subsp. majus (Aiton) N. Robson Essential Oil  

Microsoft Academic Search

Essential oils obtained by hydrodistillation of leaves (LV), flowers (FL) and fruits (FR) of Hypericum hircinum subsp. majus from Marche (Italy), were analyzed by gas chromatography-flame ionization detector (GC-FID) and gas chromatography\\/mass spectrometry (GC\\/MS). Ninety-two volatile components were identified in the oils, representing 81.4194.36% of the total oils. The major compounds were cis-?-guaiene (23.2541.23%) and ?-selinene (8.4825.20%) in LV, ?-selinene

F. Maggi; B. Tirillini; S. Vittori; G. Sagratini; F. Papa

2010-01-01

290

Three new glycosides from the leaves of Hydrangea macrophylla subsp. serrata (THUNB.) MAKINO.  

PubMed

Three new glycosides, 7-deoxyloganic acid beta-D-glucopyranosyl ester (1), (3R)-hydrangenol 8,4'-di-O-beta-D-glucopyranoside (2), and (6R,7E,9R)-megastigma-4,7-dien-3-one 9,13-di-O-beta-D-glucopyranoside (3), have been isolated from the leaves of Hydrangea macrophylla subsp. serrata (THUNB.) MAKINO (Saxifragaceae). The structures of 1-3 were elucidated on the basis of spectral data and chemical evidence. PMID:18379120

Kikuchi, Masao; Kakuda, Rie; Kikuchi, Masafumi; Yaoita, Yasunori

2008-04-01

291

Genetic IS901 RFLP diversity among Mycobacterium avium subsp. avium isolates from four pheasant flocks  

PubMed Central

IS901 RFLP analysis of 36 Mycobacterium avium subsp. avium (MAA) isolates from 15 pheasants (Phasianus colchicus) and two goshawks (Accipiter gentilis) from four pheasant farms was performed. Using this method, six different IS901 RFLP types (E, F, G, M, Q, and V) were identified. The distribution of IS901 RFLP profiles was tightly linked to individual flocks. Matching IS901 RFLP profiles observed in the present study indicate MAA transmission between pheasants and goshawks in the same locality. In two flocks, different pheasants within a flock as well as in various organs of five individual pheasants were found to have two distinct IS901 RFLP profiles. PMID:23388436

Moravkova, Monika; Lamka, Jiri; Slany, Michal

2013-01-01

292

Genetic IS901 RFLP diversity among Mycobacterium avium subsp. avium isolates from four pheasant flocks.  

PubMed

IS901 RFLP analysis of 36 Mycobacterium avium subsp. avium (MAA) isolates from 15 pheasants (Phasianus colchicus) and two goshawks (Accipiter gentilis) from four pheasant farms was performed. Using this method, six different IS901 RFLP types (E, F, G, M, Q, and V) were identified. The distribution of IS901 RFLP profiles was tightly linked to individual flocks. Matching IS901 RFLP profiles observed in the present study indicate MAA transmission between pheasants and goshawks in the same locality. In two flocks, different pheasants within a flock as well as in various organs of five individual pheasants were found to have two distinct IS901 RFLP profiles. PMID:23388436

Moravkova, Monika; Lamka, Jiri; Slany, Michal; Pavlik, Ivo

2013-01-01

293

Complete genome sequence of the ethanol-producing Zymomonas mobilis subsp. mobilis centrotype ATCC 29191.  

PubMed

Zymomonas mobilis is an ethanologenic bacterium that has been studied for use in biofuel production. Of the sequenced Zymomonas strains, ATCC 29191 has been described as the phenotypic centrotype of Zymomonas mobilis subsp. mobilis, the taxon that harbors the highest ethanol-producing Z. mobilis strains. ATCC 29191 was isolated in Kinshasa, Congo, from palm wine fermentations. This strain is reported to be a robust levan producer, while in recent years it has been employed in studies addressing Z. mobilis respiration. Here we announce the finishing and annotation of the ATCC 29191 genome, which comprises one chromosome and three plasmids. PMID:23045486

Desiniotis, Andreas; Kouvelis, Vassili N; Davenport, Karen; Bruce, David; Detter, Chris; Tapia, Roxanne; Han, Cliff; Goodwin, Lynne A; Woyke, Tanja; Kyrpides, Nikos C; Typas, Milton A; Pappas, Katherine M

2012-11-01

294

Purification and characterization of a prolidase from Lactobacillus casei subsp. casei IFPL 731.  

PubMed Central

A peptidase showing a high level of specificity towards dipeptides of the X-Pro type was purified to homogeneity from the cell extract of Lactobacillus casei subsp. casei IFPL 731. The enzyme was a monomer having a molecular mass of 41 kDa. The pH and temperature optima were 6.5 to 7.5 and 55 degrees C, respectively. Metal chelating agents completely inhibited enzyme activity, indicating that the prolidase was a metalloenzyme. The Michaelis constant (K(m)) and Vmax for several proline-containing dipeptides were determined. PMID:8979358

Fernndez-Espl, M D; Martn-Hernndez, M C; Fox, P F

1997-01-01

295

High-Throughput Direct Fecal PCR Assay for Detection of Mycobacterium avium subsp. paratuberculosis in Sheep and Cattle  

PubMed Central

Johne's disease (JD) is a chronic enteric disease caused by Mycobacterium avium subsp. paratuberculosis that affects ruminants. Transmission occurs by the fecal-oral route. A commonly used antemortem diagnostic test for the detection of M. avium subsp. paratuberculosis in feces is liquid culture; however, a major constraint is the 2- to 3-month incubation period needed for this method. Rapid methods for the detection of M. avium subsp. paratuberculosis based on PCR have been reported, but comprehensive validation data are lacking. We describe here a new test, the high-throughput-Johnes (HT-J), to detect M. avium subsp. paratuberculosis in feces. Its diagnostic accuracy was compared with that of liquid radiometric (Bactec) fecal culture using samples from cattle (1,330 samples from 23 herds) and sheep (596 samples from 16 flocks). The multistage protocol involves the recovery of M. avium subsp. paratuberculosis cells from a fecal suspension, cell rupture by bead beating, extraction of DNA using magnetic beads, and IS900 quantitative PCR. The limit of detection of the assay was 0.0005 pg, and the limit of quantification was 0.005 pg M. avium subsp. paratuberculosis genomic DNA. Only M. avium subsp. paratuberculosis was detected from a panel of 51 mycobacterial isolates, including 10 with IS900-like sequences. Of the 549 culture-negative fecal samples from unexposed herds and flocks, 99% were negative in the HT-J test, while 60% of the bovine- and 84% of the ovine-culture-positive samples were positive in the HT-J test. As similar total numbers of samples from M. avium subsp. paratuberculosis-exposed animals were positive in culture and HT-J tests in both species, and as the results of a McNemar's test were not significant, these methods probably have similar sensitivities, but the true diagnostic sensitivities of these tests are unknown. These validation data meet the consensus-based reporting standards for diagnostic test accuracy studies for paratuberculosis and the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines (S. A. Bustin et al., Clin. Chem. 55:611622, 2009, doi:10.1373/clinchem.2008.112797). The HT-J assay has been approved for use in JD control programs in Australia and New Zealand. PMID:24352996

Waldron, Anna M.; Galea, Francesca; Whittington, Ann-Michele; Saunders, Vanessa F.; Begg, Douglas J.; de Silva, Kumudika; Purdie, Auriol C.; Whittington, Richard J.

2014-01-01

296

A novel thermo-alkali stable catalaseperoxidase from Oceanobacillus oncorhynchi subsp. incaldaniensis : purification and characterization  

Microsoft Academic Search

A novel thermo-alkali-stable catalaseperoxidase from Oceanobacillus oncorhynchi subsp. incaldaniensis subsp. nov., strain 20AG, was purified and characterized. The protein purified from the cells resulted in 110-fold purification\\u000a with a specific activity of 35,000U\\/mg. The enzyme consisted of four identical subunits of 72kDa as determined by SDS-PAGE\\u000a and the total molecular mass measured by gel filtration was 280kDa. The heme content

Valeria Calandrelli; Agata Gambacorta; Ida Romano; Vito Carratore; Licia Lama

2008-01-01

297

High-throughput direct fecal PCR assay for detection of Mycobacterium avium subsp. paratuberculosis in sheep and cattle.  

PubMed

Johne's disease (JD) is a chronic enteric disease caused by Mycobacterium avium subsp. paratuberculosis that affects ruminants. Transmission occurs by the fecal-oral route. A commonly used antemortem diagnostic test for the detection of M. avium subsp. paratuberculosis in feces is liquid culture; however, a major constraint is the 2- to 3-month incubation period needed for this method. Rapid methods for the detection of M. avium subsp. paratuberculosis based on PCR have been reported, but comprehensive validation data are lacking. We describe here a new test, the high-throughput-Johnes (HT-J), to detect M. avium subsp. paratuberculosis in feces. Its diagnostic accuracy was compared with that of liquid radiometric (Bactec) fecal culture using samples from cattle (1,330 samples from 23 herds) and sheep (596 samples from 16 flocks). The multistage protocol involves the recovery of M. avium subsp. paratuberculosis cells from a fecal suspension, cell rupture by bead beating, extraction of DNA using magnetic beads, and IS900 quantitative PCR. The limit of detection of the assay was 0.0005 pg, and the limit of quantification was 0.005 pg M. avium subsp. paratuberculosis genomic DNA. Only M. avium subsp. paratuberculosis was detected from a panel of 51 mycobacterial isolates, including 10 with IS900-like sequences. Of the 549 culture-negative fecal samples from unexposed herds and flocks, 99% were negative in the HT-J test, while 60% of the bovine- and 84% of the ovine-culture-positive samples were positive in the HT-J test. As similar total numbers of samples from M. avium subsp. paratuberculosis-exposed animals were positive in culture and HT-J tests in both species, and as the results of a McNemar's test were not significant, these methods probably have similar sensitivities, but the true diagnostic sensitivities of these tests are unknown. These validation data meet the consensus-based reporting standards for diagnostic test accuracy studies for paratuberculosis and the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) guidelines (S. A. Bustin et al., Clin. Chem. 55:611-622, 2009, doi:10.1373/clinchem.2008.112797). The HT-J assay has been approved for use in JD control programs in Australia and New Zealand. PMID:24352996

Plain, Karren M; Marsh, Ian B; Waldron, Anna M; Galea, Francesca; Whittington, Ann-Michele; Saunders, Vanessa F; Begg, Douglas J; de Silva, Kumudika; Purdie, Auriol C; Whittington, Richard J

2014-03-01

298

Environmental Survival of Mycobacterium avium subsp. paratuberculosis in Different Climatic Zones of Eastern Australia  

PubMed Central

The duration of survival of both the S and C strains of Mycobacterium avium subsp. paratuberculosis in feces was quantified in contrasting climatic zones of New South Wales, Australia, and detailed environmental temperature data were collected. Known concentrations of S and C strains in feces placed on soil in polystyrene boxes were exposed to the environment with or without the provision of shade (70%) at Bathurst, Armidale, Condobolin, and Broken Hill, and subsamples taken every 2 weeks were cultured for the presence of M. avium subsp. paratuberculosis. The duration of survival ranged from a minimum of 1 week to a maximum of 16 weeks, and the provision of 70% shade was the most important factor in extending the survival time. The hazard of death for exposed compared to shaded samples was 20 and 9 times higher for the S and C strains, respectively. Site did not affect the survival of the C strain, but for the S strain, the hazard of death was 2.3 times higher at the two arid zone sites (Broken Hill and Condobolin) than at the two temperate zone sites (Bathurst and Armidale). Temperature measurements revealed maximum temperatures exceeding 60C and large daily temperature ranges at the soil surface, particularly in exposed boxes. PMID:24463974

Begg, Douglas J.; Dhand, Navneet K.; Watt, Bruce; Whittington, Richard J.

2014-01-01

299

Persistent Infection or Successive Reinfection of Deer Mice with Bartonella vinsonii subsp. arupensis?  

PubMed Central

Bartonella infections are common in rodents. From 1994 to 2006, longitudinal studies of a rodent community, consisting mainly of deer mice (Peromyscus maniculatus), were conducted in southwestern Colorado to study hantaviruses. Blood samples from deer mice captured one or more times during the period 2003 to 2006 (n = 737) were selected to study bartonellae in deer mice. Bartonellae were found to be widely distributed in that population, with an overall prevalence of 82.4% (607/737 mice). No correlation was found between bartonella prevalence and deer mouse weight or sex. Persistent or successive infections with bartonellae were observed in deer mice captured repeatedly, with a prevalence of 83.9% (297/354), and the infection appeared to last for more than 1 year in some of them. Persistent infection with bartonellae may explain the high prevalence of these bacteria in deer mice at this site and, perhaps, elsewhere. Genetic analysis demonstrated that deer mouse-borne bartonella isolates at this site belong to the same species, B. vinsonii subsp. arupensis, demonstrating a specific relationship between B. vinsonii subsp. arupensis and deer mice. PMID:21239553

Bai, Ying; Calisher, Charles H.; Kosoy, Michael Y.; Root, J. Jeffrey; Doty, Jeffrey B.

2011-01-01

300

Cytotoxicity, antimicrobial activity and composition of essential oil from Tanacetum balsamita L. subsp. balsamita.  

PubMed

The aerial parts of Tanacetum balsamita subsp. balsamita were collected at full flowering stage from Tabriz, Iran. The essential oil was isolated by hydrodistillation and analyzed by combination of capillary GC and GC-MS. Twenty seven components were identified, representing 99.2% of the total oil. Carvone (51.0%), beta-thujone (20.8%), 1,8-cineole (4.4%) and alpha-thujone (3.2%) were the main components. The in vitro antimicrobial activity of the essential oil of T. balsamita subsp. balsamita was studied against eight Gram-positive and Gram-negative bacteria (Bacillus subtilis, B. pumulis, Enterococcus faecalis, Staphylococcus aureus, S. epidermidis, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae) and three fungi (Candida albicans, Saccharomyces cerevisiae and Aspergillus niger). The results of the antimicrobial activity of the essential oil according to the disc diffusion method and MIC values indicated that the oil exhibited moderate to high antimicrobial activity. The in vitro toxicological study based on the MTT cytotoxicity assay on human fetal skin fibroblast (HFSF) and Monkey kidney (Vero) cell lines showed IC50 values of 2500 and 1250 microg/mL, respectively. PMID:19370888

Yousefzadi, Morteza; Ebrahimi, Samad Nejad; Sonboli, Ali; Miraghasi, Farah; Ghiasi, Shahla; Arman, Mitra; Mosaffa, Nariman

2009-01-01

301

Molecular Characterization of Pigmented and Nonpigmented Isolates of Mycobacterium avium subsp. paratuberculosis  

PubMed Central

Five pigmented isolates of Mycobacterium avium subsp. paratuberculosis were examined by pulsed-field gel electrophoresis (PFGE), IS900 restriction fragment length polymorphism (IS900-RFLP), and IS1311 polymorphism analysis using PCR. All of the pigmented isolates exhibited one of three distinct PFGE profiles with SnaBI, designated 9, 10, and 11, and with SpeI, designated 7, 8, and 9, which generated three multiplex profiles designated [9-7], [10-8], and [11-9]. All of the pigmented isolates had the same IS900-RFLP BstEII and PvuII profiles. The IS900-RFLP BstEII profile was new, but the IS900-RFLP PvuII profile corresponded to PvuII type 6 of a sheep strain described by Cousins and colleagues (D. V. Cousins, S. N. Williams, A. Hope, and G. J. Eamens, Aust. Vet. J. 78:184-190, 2000). IS1311-PCR analysis typed all of the pigmented isolates as sheep (S) strains. The genetic relationship between pigmented and nonpigmented isolates was investigated by using multiplex PFGE data from the analysis of both the 5 pigmented isolates and 88 nonpigmented isolates of M. avium subsp. paratuberculosis from a variety of host species and geographic locations. It was possible to classify the isolates into two distinct types designated type I, comprising the pigmented isolates, and type II, comprising the nonpigmented isolates, which exhibit a very broad host range. PMID:11980962

Stevenson, Karen; Hughes, Valerie M.; de Juan, Lucia; Inglis, Neil F.; Wright, Frank; Sharp, J. Michael

2002-01-01

302

Experimental Inoculation of BFDV-Positive Budgerigars (Melopsittacus undulatus) with Two Mycobacterium avium subsp. avium Isolates  

PubMed Central

Beak and feather disease virus- (BFDV-) positive (naturally infected) but clinically healthy budgerigars (Melopsittacus undulatus) were inoculated with two isolates of Mycobacterium avium subsp. avium isolated from naturally infected golden pheasant (Chrysolophus pictus) and peafowl (Pavo cristatus). During a period of more than two months after inoculation, samples of cloacal and crop swabs, faeces, and blood were obtained for BFDV and Mycobacterium avium testing with PCR. Birds were euthanized nine weeks after inoculation. All infected budgerigars developed signs typical of mycobacteriosis, but more advanced clinical and pathological changes were visible in the group infected with the pheasant isolate. Only a few cloacal and crop swab samples were positive for Mycobacterium avium subsp. avium despite advanced pathological changes in the internal organs. In the groups infected with mycobacterium isolates the frequency of BFDV-positive samples was higher than in the control group. In the infected groups the frequency of BFDV was substantially higher in the cloacal swabs of birds inoculated with the pheasant isolate than in the peafowl-isolate-infected group. PMID:24738057

Sapierzynski, Rafal; Szeleszczuk, Piotr

2014-01-01

303

Chemical and biological investigations of a toxic plant from Central Africa, Magnistipula butayei subsp. montana.  

PubMed

Magnistipula butayei subsp. montana (Chrysobalanaceae) is known, in the Great Lakes Region, to possess toxicological properties. In this paper, we investigated the acute toxicity (dose levels 50-1600 mg/kg) of its aqueous extract, administered orally to adult Wistar rats. This study demonstrated that the freeze-dried aqueous extract (5%, w/w) possesses high toxicity. The extract caused hypothermia, neurological disorders, including extensor reflex of maximal convulsive induced-seizures at about 2 h after the administered dose, and death occurred (LD50=370 mg/kg) in a dose dependent manner. Blood parameter evaluation revealed slight variations, but these might not have clinical relevance. Histological examination of internal organs (lungs, liver, heart and kidneys) did not reveal any abnormality in the treated group compared to the control. Therefore, it can be concluded that Magnistipula butayei subsp. montana aqueous extract, given orally, is toxic and that its target is the central nervous system. General phytochemical screening revealed that the plant did not contain significant amounts of products known to be toxic, such as alkaloids or cardioactive glycosides, but only catechic tannins, amino acids, saponins and other aphrogen principles in the three parts of the species (fruit, leave and bark). PMID:16174557

Karangwa, C; Esters, V; Frdrich, M; Tits, M; Kadima, J N; Damas, J; Noirfalise, A; Angenot, L

2006-02-20

304

Multi-Method Approach for Characterizing the Interaction between Fusarium verticillioides and Bacillus thuringiensis Subsp. Kurstaki  

PubMed Central

Bacterial antagonists used as biocontrol agents represent part of an integrated management program to reduce pesticides in the environment. Bacillus thuringiensis is considered a good alternative as a biocontrol agent for suppressing plant pathogens such as Fusarium. In this study, we used microscopy, flow cytometry, indirect immunofluorescence, and high performance liquid chromatography to determine the interaction between B. thuringiensis subsp. kurstaki LFB-FIOCRUZ (CCGB) 257 and F. verticillioides MRC 826, an important plant pathogen frequently associated with maize. B. thuringiensis showed a strong in vitro suppressive effect on F. verticillioides growth and inhibited fumonisin production. Flow cytometry analysis was found to be adequate for characterizing the fungal cell oscillations and death during these interactions. Further studies of the antagonistic effect of this isolate against other fungi and in vivo testing are necessary to determine the efficacy of B. thuringiensis subsp. kurstaki in controlling plant pathogens. This is the first report on the use of flow cytometry for quantifying living and apoptotic F. verticillioides cells and the B. thuringiensis Cry 1Ab toxin. PMID:24739804

Rocha, Liliana O.; Tralamazza, Sabina Moser.; Reis, Gabriela M.; Rabinovitch, Leon; Barbosa, Cynara B.; Correa, Benedito

2014-01-01

305

Response of Endophytic Bacterial Communities in Potato Plants to Infection with Erwinia carotovora subsp. atroseptica  

PubMed Central

The term endophyte refers to interior colonization of plants by microorganisms that do not have pathogenic effects on their hosts, and various endophytes have been found to play important roles in plant vitality. In this study, cultivation-independent terminal restriction fragment length polymorphism analysis of 16S ribosomal DNA directly amplified from plant tissue DNA was used in combination with molecular characterization of isolates to examine the influence of plant stress, achieved by infection with the blackleg pathogen Erwinia carotovora subsp. atroseptica, on the endophytic population in two different potato varieties. Community analysis clearly demonstrated increased bacterial diversity in infected plants compared to that in control plants. The results also indicated that the pathogen stress had a greater impact on the bacteria population than the plant genotype had. Partial sequencing of the 16S rRNA genes of isolated endophytes revealed a broad phylogenetic spectrum of bacteria, including members of the ?, ?, and ? subgroups of the Proteobacteria, high- and low-G+C-content gram-positive organisms, and microbes belonging to the Flexibacter-Cytophaga-Bacteroides group. Screening of the isolates for antagonistic activity against E. carotovora subsp. atroseptica revealed that 38% of the endophytes protected tissue culture plants from blackleg disease. PMID:11976096

Reiter, Birgit; Pfeifer, Ulrike; Schwab, Helmut; Sessitsch, Angela

2002-01-01

306

Complete Genome Sequence of the Prototype Lactic Acid Bacterium Lactococcus lactis subsp. cremoris MG1363?  

PubMed Central

Lactococcus lactis is of great importance for the nutrition of hundreds of millions of people worldwide. This paper describes the genome sequence of Lactococcus lactis subsp. cremoris MG1363, the lactococcal strain most intensively studied throughout the world. The 2,529,478-bp genome contains 81 pseudogenes and encodes 2,436 proteins. Of the 530 unique proteins, 47 belong to the COG (clusters of orthologous groups) functional category carbohydrate metabolism and transport, by far the largest category of novel proteins in comparison with L. lactis subsp. lactis IL1403. Nearly one-fifth of the 71 insertion elements are concentrated in a specific 56-kb region. This integration hot-spot region carries genes that are typically associated with lactococcal plasmids and a repeat sequence specifically found on plasmids and in the lateral gene transfer hot spot in the genome of Streptococcus thermophilus. Although the parent of L. lactis MG1363 was used to demonstrate lysogeny in Lactococcus, L. lactis MG1363 carries four remnant/satellite phages and two apparently complete prophages. The availability of the L. lactis MG1363 genome sequence will reinforce its status as the prototype among lactic acid bacteria through facilitation of further applied and fundamental research. PMID:17307855

Wegmann, Udo; O'Connell-Motherway, Mary; Zomer, Aldert; Buist, Girbe; Shearman, Claire; Canchaya, Carlos; Ventura, Marco; Goesmann, Alexander; Gasson, Michael J.; Kuipers, Oscar P.; van Sinderen, Douwe; Kok, Jan

2007-01-01

307

Photobacterium damselae subsp. damselae, a bacterium pathogenic for marine animals and humans  

PubMed Central

Photobacterium damselae subsp. damselae (formerly Vibrio damsela) is a pathogen of a variety of marine animals including fish, crustaceans, molluscs, and cetaceans. In humans, it can cause opportunistic infections that may evolve into necrotizing fasciitis with fatal outcome. Although the genetic basis of virulence in this bacterium is not completely elucidated, recent findings demonstrate that the phospholipase-D Dly (damselysin) and the pore-forming toxins HlyApl and HlyAch play a main role in virulence for homeotherms and poikilotherms. The acquisition of the virulence plasmid pPHDD1 that encodes Dly and HlyApl has likely constituted a main driving force in the evolution of a highly hemolytic lineage within the subspecies. Interestingly, strains that naturally lack pPHDD1 show a strong pathogenic potential for a variety of fish species, indicating the existence of yet uncharacterized virulence factors. Future and deep analysis of the complete genome sequence of Photobacterium damselae subsp. damselae will surely provide a clearer picture of the virulence factors employed by this bacterium to cause disease in such a varied range of hosts. PMID:24093021

Rivas, Amable J.; Lemos, Manuel L.; Osorio, Carlos R.

2013-01-01

308

Persistent infection or successive reinfection of deer mice with Bartonella vinsonii subsp. arupensis.  

PubMed

Bartonella infections are common in rodents. From 1994 to 2006, longitudinal studies of a rodent community, consisting mainly of deer mice (Peromyscus maniculatus), were conducted in southwestern Colorado to study hantaviruses. Blood samples from deer mice captured one or more times during the period 2003 to 2006 (n = 737) were selected to study bartonellae in deer mice. Bartonellae were found to be widely distributed in that population, with an overall prevalence of 82.4% (607/737 mice). No correlation was found between bartonella prevalence and deer mouse weight or sex. Persistent or successive infections with bartonellae were observed in deer mice captured repeatedly, with a prevalence of 83.9% (297/354), and the infection appeared to last for more than 1 year in some of them. Persistent infection with bartonellae may explain the high prevalence of these bacteria in deer mice at this site and, perhaps, elsewhere. Genetic analysis demonstrated that deer mouse-borne bartonella isolates at this site belong to the same species, B. vinsonii subsp. arupensis, demonstrating a specific relationship between B. vinsonii subsp. arupensis and deer mice. PMID:21239553

Bai, Ying; Calisher, Charles H; Kosoy, Michael Y; Root, J Jeffrey; Doty, Jeffrey B

2011-03-01

309

Antioxidant Potential, Lipid Peroxidation Inhibition and Antimicrobial Activities of Satureja montana L. subsp. kitaibelii Extracts  

PubMed Central

The antioxidant activity of different Satureja montana L. subsp. kitaibelii extracts was tested by measuring their ability to scavenge reactive hydroxyl radical during the Fenton reaction, using ESR spectroscopy. Also, the influence of these extracts on lipid peroxyl radicals obtained during lipid peroxidation of: (I) sunflower oil (37 C, 3h) induced by 4,4?-azobis(4-cyanovaleric acid) (ACVA) and (II) liposomes induced by 2,2?-azobis(2- amidino-propane)dihydrochloride (AAPH) was studied. n-Butanol extract had the best antioxidant activity (100% at 0.5 mg/mL in Fenton reaction system; 89.21% at 5 mg/mL in system I; 83.38% at 5 mg/mL in system II). The antioxidant activities of the extracts significantly correlated with total phenolic content. The antimicrobial activity of Satureja montana L. subsp. kitaibelii extracts was investigated. Petroleum ether, chloroform and ethyl acetate extracts expressed a wide range of inhibiting activity against both grampositive and gram-negative bacteria.

Cetkovic, Gordana S.; Canadanovic-Brunet, Jasna M.; Djilas, Sonja M.; Tumbas, Vesna T.; Markov, Sinisa L.; Cvetkovic, Dragoljub D.

2007-01-01

310

Mycobacterium avium subsp. hominissuis Infection in Swine Associated with Peat Used for Bedding  

PubMed Central

Mycobacterium avium subsp. hominissuis is an environmental bacterium causing opportunistic infections in swine, resulting in economic losses. Additionally, the zoonotic aspect of such infections is of concern. In the southeastern region of Norway in 2009 and 2010, an increase in condemnation of pig carcasses with tuberculous lesions was seen at the meat inspection. The use of peat as bedding in the herds was suspected to be a common factor, and a project examining pigs and environmental samples from the herds was initiated. Lesions detected at meat inspection in pigs originating from 15 herds were sampled. Environmental samples including peat from six of the herds and from three peat production facilities were additionally collected. Samples were analysed by culture and isolates genotyped by MLVA analysis. Mycobacterium avium subsp. hominissuis was detected in 35 out of 46 pigs, in 16 out of 20 samples of peat, and in one sample of sawdust. MLVA analysis demonstrated identical isolates from peat and pigs within the same farms. Polyclonal infection was demonstrated by analysis of multiple isolates from the same pig. To conclude, the increase in condemnation of porcine carcasses at slaughter due to mycobacteriosis seemed to be related to untreated peat used as bedding.

Johansen, Tone Bjordal; Lium, Bjrn; Jrgensen, Anne; Djnne, Berit

2014-01-01

311

A metabolic enzyme as a primary virulence factor of Mycoplasma mycoides subsp. mycoides small colony.  

PubMed

During evolution, pathogenic bacteria have developed complex interactions with their hosts. This has frequently involved the acquisition of virulence factors on pathogenicity islands, plasmids, transposons, or prophages, allowing them to colonize, survive, and replicate within the host. In contrast, Mycoplasma species, the smallest self-replicating organisms, have regressively evolved from gram-positive bacteria by reduction of the genome to a minimal size, with the consequence that they have economized their genetic resources. Hence, pathogenic Mycoplasma species lack typical primary virulence factors such as toxins, cytolysins, and invasins. Consequently, little is known how pathogenic Mycoplasma species cause host cell damage, inflammation, and disease. Here we identify a novel primary virulence determinant in Mycoplasma mycoides subsp. mycoides Small Colony (SC), which causes host cell injury. This virulence factor, released in significant amounts in the presence of glycerol in the growth medium, consists of toxic by-products such as H2O2 formed by l-alpha-glycerophosphate oxidase (GlpO), a membrane-located enzyme that is involved in the metabolism of glycerol. When embryonic calf nasal epithelial cells are infected with M. mycoides subsp. mycoides SC in the presence of physiological amounts of glycerol, H2O2 is released inside the cells prior to cell death. This process can be inhibited with monospecific anti-GlpO antibodies. PMID:16166545

Pilo, Paola; Vilei, Edy M; Peterhans, Ernst; Bonvin-Klotz, Laetitia; Stoffel, Michael H; Dobbelaere, Dirk; Frey, Joachim

2005-10-01

312

Persistence of Mycobacterium avium subsp. paratuberculosis at a Farm-Scale Biogas Plant Supplied with Manure from Paratuberculosis-Affected Dairy Cattle?  

PubMed Central

In this study, products from all steps of anaerobic digestion at a farm-scale biogas plant supplied with manure from paratuberculosis-affected dairy cattle were examined and quantified for the presence of the causal agent of paratuberculosis, Mycobacterium avium subsp. paratuberculosis, using culture and quantitative real-time PCR (qPCR). Viable M. avium subsp. paratuberculosis cells were detected using culture in fermentors for up to 2 months; the presence of M. avium subsp. paratuberculosis DNA (101 cells/g) was demonstrated in all anaerobic fermentors and digestate 16 months after initiation of work at a biogas plant, using IS900 qPCR. F57 qPCR was able to detect M. avium subsp. paratuberculosis DNA (102 cells/g) at up to 12 months. According to these results, a fermentation process that extended beyond 2 months removed all viable M. avium subsp. paratuberculosis cells and therefore rendered its product M. avium subsp. paratuberculosis free. However, M. avium subsp. paratuberculosis DNA was found during all the examined periods (more than 1 year), which could be explained by either residual DNA being released from dead cells or by the presence of viable cells whose amount was under the limit of cultivability. As the latter hypothesis cannot be excluded, the safety of the final products of digestion used for fertilization or animal bedding cannot be defined, and further investigation is necessary to confirm or refute this risk. PMID:21398476

Slana, I.; Pribylova, R.; Kralova, A.; Pavlik, I.

2011-01-01

313

Derivation of Mutants of Erwinia carotovora subsp. betavasculorum Deficient in Export of Pectolytic Enzymes with Potential for Biological Control of Potato Soft Rot  

PubMed Central

Erwinia carotovora subsp. betavasculorum Ecb168 produces an antibiotic(s) that suppresses growth of the related bacterium Erwinia carotovora subsp. carotovora in culture and in wounds of potato tubers. Strain Ecb168 also produces and secretes pectolytic enzymes and causes a vascular necrosis and root rot of sugar beet. Genes (out) involved in secretion of pectolytic enzymes by Ecb168 were localized to two HindIII fragments (8.5 and 10.5 kb) of Ecb168 genomic DNA by hybridization to the cloned out region of E. carotovora subsp. carotovora and by complementation of Out- mutants of E. carotovora subsp. carotovora. Out- mutants of Ecb168, which did not secrete pectate lyase into the culture medium, were obtained when deletions internal to either HindIII fragment were introduced into the genome of Ecb168 through marker exchange mutagenesis. Out- mutants of Ecb168 were complemented to the Out+ phenotype by introduction of the corresponding cloned HindIII fragment. Out- mutants of Ecb168 were less virulent than the Out+ parental strain on potato tubers. Strain Ecb168 and Out- derivatives inhibited the growth of E. carotovora subsp. carotovora in culture, indicating that the uncharacterized antibiotic(s) responsible for antagonism was exported through an out-independent mechanism. Strain Ecb168 and Out- derivatives reduced the establishment of large populations of E. carotovora subsp. carotovora in wounds of potato tubers and suppressed tuber soft rot caused by E. carotovora subsp. carotovora. PMID:16349316

Costa, Jose M.; Loper, Joyce E.

1994-01-01

314

Effects of long-term exposure to ammonium sulfate particles on growth and gas exchange rates of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica seedlings  

NASA Astrophysics Data System (ADS)

To clarify the effects of long-term exposure to ammonium sulfate (AS) particles on growth and physiological functions of forest tree species, seedlings of Fagus crenata, Castanopsis sieboldii, Larix kaempferi and Cryptomeria japonica were exposed to submicron-size AS particles during two growing seasons from 3 June 2011 to 8 October 2012. The mean sulfate concentration in PM2.5 increased during the exposure inside the chamber in 2011 and 2012 by 2.73 and 4.32?gSO42-m-3, respectively. No significant effects of exposure to AS particles were detected on the whole-plant dry mass of the seedlings. These results indicate that the exposure to submicrometer AS particles at the ambient level for two growing seasons did not significantly affect the growth of the seedlings. No significant effects of exposure to AS particles were found on the net photosynthetic rate in the leaves or needles of F.crenata, C.sieboldii and L.kaempferi seedlings. Also, in the previous-year needles of C.japonica seedlings, exposure to AS particles significantly reduced the net photosynthetic rate, which may be caused by the reduction in the concentration of ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco). On the contrary, in current-year needles of C.japonica seedlings, net photosynthetic rate significantly increased with exposure to AS particles, which may be the result of increases in stomatal conductance and concentrations of Rubisco and chlorophyll. Furthermore, exposure to AS particles correlated with an increase in concentrations of NH4+, free amino acid and total soluble protein, suggesting that AS particles may be deliquesced, absorbed into the leaves and metabolized into amino acid and protein. These results suggest that net photosynthesis in the needles of C.japonica is relatively sensitive to submicron-size AS particles as compared with the other three tree species.

Yamaguchi, Masahiro; Otani, Yoko; Li, Peiran; Nagao, Hiroshi; Lenggoro, I. Wuled; Ishida, Atsushi; Yazaki, Kenichi; Noguchi, Kyotaro; Nakaba, Satoshi; Yamane, Kenichi; Kuroda, Katsushi; Sano, Yuzou; Funada, Ryo; Izuta, Takeshi

2014-11-01

315

Local adaptations to frost in marginal and central populations of the dominant forest tree Fagus sylvatica L. as affected by temperature and extreme drought in common garden experiments  

PubMed Central

Local adaptations to environmental conditions are of high ecological importance as they determine distribution ranges and likely affect species responses to climate change. Increased environmental stress (warming, extreme drought) due to climate change in combination with decreased genetic mixing due to isolation may lead to stronger local adaptations of geographically marginal than central populations. We experimentally observed local adaptations of three marginal and four central populations of Fagus sylvaticaL., the dominant native forest tree, to frost over winter and in spring (late frost). We determined frost hardiness of buds and roots by the relative electrolyte leakage in two common garden experiments. The experiment at the cold site included a continuous warming treatment; the experiment at the warm site included a preceding summer drought manipulation. In both experiments, we found evidence for local adaptation to frost, with stronger signs of local adaptation in marginal populations. Winter frost killed many of the potted individuals at the cold site, with higher survival in the warming treatment and in those populations originating from colder environments. However, we found no difference in winter frost tolerance of buds among populations, implying that bud survival was not the main cue for mortality. Bud late frost tolerance in April differed between populations at the warm site, mainly because of phenological differences in bud break. Increased spring frost tolerance of plants which had experienced drought stress in the preceding summer could also be explained by shifts in phenology. Stronger local adaptations to climate in geographically marginal than central populations imply the potential for adaptation to climate at range edges. In times of climate change, however, it needs to be tested whether locally adapted populations at range margins can successfully adapt further to changing conditions. PMID:25035801

Kreyling, Juergen; Buhk, Constanze; Backhaus, Sabrina; Hallinger, Martin; Huber, Gerhard; Huber, Lukas; Jentsch, Anke; Konnert, Monika; Thiel, Daniel; Wilmking, Martin; Beierkuhnlein, Carl

2014-01-01

316

Light and competition gradients fail to explain the coexistence of shade-tolerant Fagus sylvatica and shade-intermediate Quercus petraea seedlings  

PubMed Central

Background and Aims The coexistence of forest tree species has often been linked to differences among species in terms of their response to light availability during the regeneration stage. From this perspective, species coexistence results from growthgrowth or mortalitygrowth trade-offs along spatial light gradients. Experimental evidence of growthgrowth trade-offs in natural conditions is sparse due to various confounding factors that potentially hinder the relationship. This study examined growth hierarchies along light gradients between two tree species with contrasting shade tolerance by controlling potential confounding factors such as seedling size, seedling status, seedling density and species composition. Methods Natural regenerated shade-tolerant Fagus sylvatica and shade-intermediate Quercus petraea seedlings were used, and growth rankings over a 4-year period were compared in 8- to 10-year-old tree seedlings. Key results No rank reversal occurs between the two species along the light gradient, or along the density, mixture or seedling size gradients. The shade-tolerant species was always the more competitive of the two. Pronounced effects of initial size on seedling growth were observed, whereas the effects of light and competition by neighbours were of secondary importance. The paramount effect of size, which results from the asymmetric nature of interseedling competition, gives a strong advantage to tall seedlings over the long term. Conclusions This study extends previous efforts to identify potential drivers of rank reversals in young tree mixtures. It does not support the classical assumption that spatial heterogeneity in canopy opening explains the coexistence of the two species studied. It suggests that spatial variation in local size hierarchies among seedlings that may be caused by seedling emergence time or seedling initial performance is the main driver of the dynamics of these mixed stands. PMID:24036670

Van Couwenberghe, Rosalinde; Gegout, Jean-Claude; Lacombe, Eric; Collet, Catherine

2013-01-01

317

Local adaptations to frost in marginal and central populations of the dominant forest tree Fagus sylvatica L. as affected by temperature and extreme drought in common garden experiments.  

PubMed

Local adaptations to environmental conditions are of high ecological importance as they determine distribution ranges and likely affect species responses to climate change. Increased environmental stress (warming, extreme drought) due to climate change in combination with decreased genetic mixing due to isolation may lead to stronger local adaptations of geographically marginal than central populations. We experimentally observed local adaptations of three marginal and four central populations of Fagus sylvaticaL., the dominant native forest tree, to frost over winter and in spring (late frost). We determined frost hardiness of buds and roots by the relative electrolyte leakage in two common garden experiments. The experiment at the cold site included a continuous warming treatment; the experiment at the warm site included a preceding summer drought manipulation. In both experiments, we found evidence for local adaptation to frost, with stronger signs of local adaptation in marginal populations. Winter frost killed many of the potted individuals at the cold site, with higher survival in the warming treatment and in those populations originating from colder environments. However, we found no difference in winter frost tolerance of buds among populations, implying that bud survival was not the main cue for mortality. Bud late frost tolerance in April differed between populations at the warm site, mainly because of phenological differences in bud break. Increased spring frost tolerance of plants which had experienced drought stress in the preceding summer could also be explained by shifts in phenology. Stronger local adaptations to climate in geographically marginal than central populations imply the potential for adaptation to climate at range edges. In times of climate change, however, it needs to be tested whether locally adapted populations at range margins can successfully adapt further to changing conditions. PMID:25035801

Kreyling, Juergen; Buhk, Constanze; Backhaus, Sabrina; Hallinger, Martin; Huber, Gerhard; Huber, Lukas; Jentsch, Anke; Konnert, Monika; Thiel, Daniel; Wilmking, Martin; Beierkuhnlein, Carl

2014-03-01

318

Within-Population Genetic Structure in Beech (Fagus sylvatica L.) Stands Characterized by Different Disturbance Histories: Does Forest Management Simplify Population Substructure?  

PubMed Central

The fine-scale assessment of both spatially and non-spatially distributed genetic variation is crucial to preserve forest genetic resources through appropriate forest management. Cryptic within-population genetic structure may be more common than previously thought in forest tree populations, which has strong implications for the potential of forests to adapt to environmental change. The present study was aimed at comparing within-population genetic structure in European beech (Fagus sylvatica L.) plots experiencing different disturbance levels. Five plot pairs made up by disturbed and undisturbed plots having the same biogeographic history were sampled throughout Europe. Overall, 1298 individuals were analyzed using four highly polymorphic nuclear microsatellite markers (SSRs). Bayesian clustering within plots identified 3 to 11 genetic clusters (within-plot ?ST ranged from 0.025 to 0.124). The proportion of within-population genetic variation due to genetic substructuring (FCluPlot?=?0.067) was higher than the differentiation among the 10 plots (FPlotTot?=?0.045). Focusing on the comparison between managed and unmanaged plots, disturbance mostly explains differences in the complexity of within-population genetic structure, determining a reduction of the number of genetic clusters present in a standardized area. Our results show that: i) genetic substructuring needs to be investigated when studying the within-population genetic structure in forest tree populations, and ii) indices describing subtle characteristics of the within-population genetic structure are good candidates for providing early signals of the consequences of forest management, and of disturbance events in general. PMID:24039930

Piotti, Andrea; Leonardi, Stefano; Heuertz, Myriam; Buiteveld, Joukje; Geburek, Thomas; Gerber, Sophie; Kramer, Koen; Vettori, Cristina; Vendramin, Giovanni Giuseppe

2013-01-01

319

Persistence of Mycobacterium avium subsp. paratuberculosis in soil, crops, and ensiled feed following manure spreading on infected dairy farms  

PubMed Central

The goal of this study was to determine the persistence of Mycobacterium avium subsp. paratuberculosis (MAP) in soil, crops, and ensiled feeds following manure spreading. This bacterium was often found in soil samples, but less frequently in harvested feeds and silage. Spreading of manure on fields used for crop harvest is preferred to spreading on grazing pastures. PMID:24179246

Fecteau, Marie-Eve; Hovingh, Ernest; Whitlock, Robert H.; Sweeney, Raymond W.

2013-01-01

320

Adult Invasive and Noninvasive Infections Due to Streptococcus dysgalactiae subsp. equisimilis in France from 2006 to 2010  

PubMed Central

We characterized 182 Streptococcus dysgalactiae subsp. equisimilis isolates and analyzed the epidemiological data on the corresponding infections. stG6, stG485, and stG6792 were the 3 most prevalent invasive emm types among the 27 different emm types recovered. High rates of antimicrobial resistance were observed for macrolides (26.4%) and tetracycline (34.6%). PMID:23698531

Plainvert, Celine; Collobert, Gislene; Touak, Gerald; Bouvet, Anne

2013-01-01

321

Detection of Mycobacterium avium subsp. paratuberculosis in formalin- fixed, paraffin embedded tissues of goats by IS 900 polymerase chain reaction  

Microsoft Academic Search

The objective of the present study was to optimise and evaluate a procedure for detection of Mycobacterium avium subsp. paratuberculosis in archived formalin-fixed, paraffin embedded tissue sections from cases of naturally occurring paratuberculosis in goats. A pilot study assessed 3 procedures for extraction of DNA for detection by PCR. The procedure that gave the most consistent results involved removal of

B. N. Tripathi; K. Stevenson

322

Draft Genome Sequence of Streptomyces roseochromogenes subsp. oscitans DS 12.976, Producer of the Aminocoumarin Antibiotic Clorobiocin.  

PubMed

Streptomyces roseochromogenes subsp. oscitans DS12.976 is the producer of the gyrase-inhibiting aminocoumarin antibiotic clorobiocin. Here, we present a draft genome sequence of this strain, in which we identified the clorobiocin gene cluster as well as an unusually high number (43) of further putative secondary metabolite clusters. PMID:24407645

Rckert, Christian; Kalinowski, Jrn; Heide, Lutz; Apel, Alexander Kristian

2014-01-01

323

Draft Genome Sequence of Streptomyces roseochromogenes subsp. oscitans DS 12.976, Producer of the Aminocoumarin Antibiotic Clorobiocin  

PubMed Central

Streptomyces roseochromogenes subsp. oscitans DS12.976 is the producer of the gyrase-inhibiting aminocoumarin antibiotic clorobiocin. Here, we present a draft genome sequence of this strain, in which we identified the clorobiocin gene cluster as well as an unusually high number (43) of further putative secondary metabolite clusters. PMID:24407645

Ruckert, Christian; Kalinowski, Jorn; Heide, Lutz

2014-01-01

324

Genome Sequence of Lactobacillus delbrueckii subsp. lactis CNRZ327, a Dairy Bacterium with Anti-Inflammatory Properties  

PubMed Central

Lactobacillus delbrueckii subsp. lactis CNRZ327 is a dairy bacterium with anti-inflammatory properties both in vitro and in vivo. Here, we report the genome sequence of this bacterium, which appears to contain no less than 215 insertion sequence (IS) elements, an exceptionally high number regarding the small genome size of the strain. PMID:25035318

El Kafsi, Hela; Binesse, Johan; Loux, Valentin; Buratti, Julien; Boudebbouze, Samira; Dervyn, Rozenn; Hammani, Amal; Maguin, Emmanuelle

2014-01-01

325

Genome Sequence of the Lactic Acid Bacterium Lactococcus lactis subsp. lactis TOMSC161, Isolated from a Nonscalded Curd Pressed Cheese  

PubMed Central

Lactococcus lactis is a lactic acid bacterium used in the production of many fermented foods, such as dairy products. Here, we report the genome sequence of L.lactis subsp. lactis TOMSC161, isolated from nonscalded curd pressed cheese. This genome sequence provides information in relation to dairy environment adaptation. PMID:25377704

Velly, H.; Abraham, A.-L.; Loux, V.; Delacroix-Buchet, A.; Fonseca, F.; Bouix, M.

2014-01-01

326

Genome Sequence of the Lactic Acid Bacterium Lactococcus lactis subsp. lactis TOMSC161, Isolated from a Nonscalded Curd Pressed Cheese.  

PubMed

Lactococcus lactis is a lactic acid bacterium used in the production of many fermented foods, such as dairy products. Here, we report the genome sequence of L.lactis subsp. lactis TOMSC161, isolated from nonscalded curd pressed cheese. This genome sequence provides information in relation to dairy environment adaptation. PMID:25377704

Velly, H; Renault, P; Abraham, A-L; Loux, V; Delacroix-Buchet, A; Fonseca, F; Bouix, M

2014-01-01

327

Recovery of Mycobacterium avium subsp. paratuberculosis from nematode larvae cultured from the faeces of sheep with Johnes disease  

Microsoft Academic Search

A study was conducted to determine whether trichostrongylid nematode larvae become contaminated with Mycobacterium avium subsp. paratuberculosis when they develop in the faeces of sheep with Johnes disease. Nematode larvae were hatched from ova in the faecal samples of affected sheep. Larval sheaths were removed and these as well as exsheathed larvae were subjected to radiometric culture for M.paratuberculosis. The

R. J Whittington; J. B Lloyd; L. A Reddacliff

2001-01-01

328

Genome Sequences of Strain ATCC 29281 and Pin and Northern Red Oak Isolates of Lonsdalea quercina subsp. quercina.  

PubMed

Two bacteria identified as Lonsdalea quercina subsp. quercina were isolated from oak trees showing symptoms of drippy blight. Here, we present their draft genome assemblies, as well as that of the type strain of this species. To our knowledge, these are the first published genome sequences of this subspecies of Lonsdalea quercina. PMID:24926062

Ibarra Caballero, Jorge; Zerillo, Marcelo M; Snelling, Jacob; Cranshaw, Whitney; Boucher, Christina; Tisserat, Ned

2014-01-01

329

Draft genome sequence of Enterobacter cloacae subsp. cloacae strain 08XA1, a fecal bacterium of giant pandas.  

PubMed

Enterobacter cloacae, a common pathogenic bacterium, is a Gram-negative bacillus. We analyzed the draft genome of Enterobacter cloacae subsp. cloacae strain 08XA1 from the feces of a giant panda in China. Genes encoding a ?-lactamase and efflux pumps, as well as other factors, have been found in the genome. PMID:23209197

Yan, Yue; Zhao, Chuan-Wu; Zhang, Yi-Zheng; Zhang, Zhi-He; Pan, Guang-Lin; Liu, Wen-Wang; Ma, Qing-Yi; Hou, Rong; Tan, Xue-Mei

2012-12-01

330

Infection due to extended-spectrum ?-lactamase-producing Salmonella enterica subsp. enterica serotype infantis in a neonatal unit  

Microsoft Academic Search

Objective: To describe the investigation and control of an outbreak of extended-spectrum ?-lactamase producing Salmonella enterica subsp. enterica serotype Infantis in a neonatal unit in Brazil. Methods: A case-control study for risk factors for Salmonella Infantis systemic infection, environmental cultures, and evaluation of staffing and overcrowding and an assessment of infection control practices were performed. Results: During July 1998 to

Carmem Lcia Pessoa-Silva; Cristiana M. Toscano; Beatriz Meurer Moreira; Ana Lcia Santos; Ana Cristina Cisne Frota; Claude Andre Solari; Efignia L. T. Amorim; Maria da Gloria S. Carvalho; Lcia Martins Teixeira; William R. Jarvis

2002-01-01

331

Isolation of Mycobacterium avium subsp paratuberculosis (Map) from Feral Cats on a Dairy Farm with Map-infected Cattle  

Microsoft Academic Search

Paratuberculosis is an economical- ly important disease of dairy cattle caused by Mycobacterium avium subsp. paratuberculosis (Map). The role of nonruminant, nondomestic animals in the epidemiology of paratuberculosis in cattle is unclear. To examine nonruminant, nondomestic animals for the presence of Map, 25 feral cats, nine mice (species unknown), eight rabbits (Sylvilagus floridanus), six rac- coons (Procyon lotor), and three

Mitchell V. Palmer; William C. Stoffregen; Jeremy G. Carpenter; Judith R. Stabel

2005-01-01

332

Evaluation of four commercial serum ELISAs for detection of Mycobacterium avium subsp. paratuberculosis infection in dairy cows  

Microsoft Academic Search

During the first 3months of 2006, a study was performed on four dairy cattle herds with a history of clinical paratuberculosis, to evaluate different enzyme-linked immunosorbent assays (ELISAs). Serum samples obtained from 326 animals were analysed using four ELISAs to detect antibodies to Mycobacterium avium subsp. paratuberculosis (MAP). Kappa (?) concordance coefficients in pairwise comparisons of the ELISA outcomes ranged

Francisco J. Diguez; Ana M. Gonzlez; Santiago Menndez; Mara J. Vilar; Mara L. Sanjun; Eduardo Yus; Ignacio Arnaiz

2009-01-01

333

Reproductive potential and seed fate of Sclerocarya birrea subsp. caffra (marula) in the low altitude savannas of South Africa  

Microsoft Academic Search

Even though Sclerocarya birrea subsp. caffra (marula) is a well-studied, keystone tree species with high ecological, commercial and cultural value, significant gaps in our understanding of its reproductive biology exist, particularly the factors limiting fruit and seed production, seed fate and the persistence of the seed bank. Therefore, a detailed quantitative assessment of these factors was conducted at five sites

C. V. Helm; S. L. Scott; E. T. F. Witkowski

2011-01-01

334

Management of Sinapis alba subsp. mairei winter cover crop residues for summer weed control in southern Spain  

Microsoft Academic Search

Sinapis alba subsp. mairei (H. Lindb. fil.) Maire, a wild subspecies of S. alba L., which is distributed throughout the Mediterranean basin, has been recently introduced in southern Spain as a winter cover crop in olive groves. The reason behind using this cover crop is for the reduction of Verticillium dahliae inoculum. The effectiveness of this cover crop for weed

C. Alcntara; A. Pujadas; M. Saavedra

2011-01-01

335

First Fully Closed Genome Sequence of Salmonella enterica subsp. enterica Serovar Cubana Associated with a Food-Borne Outbreak.  

PubMed

Salmonella enterica subsp. enterica serovar Cubana (Salmonella serovar Cubana) is associated with human and animal disease. Here, we used third-generation, single-molecule, real-time DNA sequencing to determine the first complete genome sequence of Salmonella serovar Cubana CFSAN002050, which was isolated from fresh alfalfa sprouts during a multistate outbreak in 2012. PMID:25359917

Hoffmann, Maria; Muruvanda, Tim; Pirone, Cary; Korlach, Jonas; Timme, Ruth; Payne, Justin; Evans, Peter; Meng, Jianghong; Brown, Eric W; Allard, Marc W

2014-01-01

336

First Fully Closed Genome Sequence of Salmonella enterica subsp. enterica Serovar Cubana Associated with a Food-Borne Outbreak  

PubMed Central

Salmonella enterica subsp. enterica serovar Cubana (Salmonella serovar Cubana) is associated with human and animal disease. Here, we used third-generation, single-molecule, real-time DNA sequencing to determine the first complete genome sequence of Salmonella serovar Cubana CFSAN002050, which was isolated from fresh alfalfa sprouts during a multistate outbreak in 2012. PMID:25359917

Muruvanda, Tim; Pirone, Cary; Korlach, Jonas; Timme, Ruth; Payne, Justin; Evans, Peter; Meng, Jianghong; Brown, Eric W.; Allard, Marc W.

2014-01-01

337

Culture- and quantitative IS900 real-time PCR-based analysis of the persistence of Mycobacterium avium subsp. paratuberculosis in a controlled dairy cow farm environment.  

PubMed

The aim of this study was to monitor the persistence of Mycobacterium avium subsp. paratuberculosis in environmental samples taken from a Holstein farm with a long history of clinical paratuberculosis. A herd of 606 head was eradicated, and mechanical cleaning and disinfection with chloramine B with ammonium (4%) was carried out on the farm; in the surrounding areas (on the field and field midden) lime was applied. Environmental samples were collected before and over a period of 24 months after destocking. Only one sample out of 48 (2%) examined on the farm (originating from a waste pit and collected before destocking) was positive for M. avium subsp. paratuberculosis by cultivation on solid medium (Herrold's egg yolk medium). The results using real-time quantitative PCR (qPCR) showed that a total of 81% of environmental samples with an average mean M. avium subsp. paratuberculosis cell number of 3.09 10(3) were positive for M. avium subsp. paratuberculosis before destocking compared to 43% with an average mean M. avium subsp. paratuberculosis cell number of 5.86 10(2) after 24 months. M. avium subsp. paratuberculosis-positive samples were detected in the cattle barn as well as in the calf barn and surrounding areas. M. avium subsp. paratuberculosis was detected from different matrices: floor and instrument scrapings, sediment, or scraping from watering troughs, waste pits, and cobwebs. M. avium subsp. paratuberculosis DNA was also detected in soil and plants collected on the field midden and the field 24 months after destocking. Although the proportion of positive samples decreased from 64% to 23% over time, the numbers of M. avium subsp. paratuberculosis cells were comparable. PMID:22773642

Moravkova, M; Babak, V; Kralova, A; Pavlik, I; Slana, I

2012-09-01

338

Culture- and Quantitative IS900 Real-Time PCR-Based Analysis of the Persistence of Mycobacterium avium subsp. paratuberculosis in a Controlled Dairy Cow Farm Environment  

PubMed Central

The aim of this study was to monitor the persistence of Mycobacterium avium subsp. paratuberculosis in environmental samples taken from a Holstein farm with a long history of clinical paratuberculosis. A herd of 606 head was eradicated, and mechanical cleaning and disinfection with chloramine B with ammonium (4%) was carried out on the farm; in the surrounding areas (on the field and field midden) lime was applied. Environmental samples were collected before and over a period of 24 months after destocking. Only one sample out of 48 (2%) examined on the farm (originating from a waste pit and collected before destocking) was positive for M. avium subsp. paratuberculosis by cultivation on solid medium (Herrold's egg yolk medium). The results using real-time quantitative PCR (qPCR) showed that a total of 81% of environmental samples with an average mean M. avium subsp. paratuberculosis cell number of 3.09 103 were positive for M. avium subsp. paratuberculosis before destocking compared to 43% with an average mean M. avium subsp. paratuberculosis cell number of 5.86 102 after 24 months. M. avium subsp. paratuberculosis-positive samples were detected in the cattle barn as well as in the calf barn and surrounding areas. M. avium subsp. paratuberculosis was detected from different matrices: floor and instrument scrapings, sediment, or scraping from watering troughs, waste pits, and cobwebs. M. avium subsp. paratuberculosis DNA was also detected in soil and plants collected on the field midden and the field 24 months after destocking. Although the proportion of positive samples decreased from 64% to 23% over time, the numbers of M. avium subsp. paratuberculosis cells were comparable. PMID:22773642

Moravkova, M.; Babak, V.; Kralova, A.; Pavlik, I.

2012-01-01

339

Chemical decontamination with N-acetyl-L-cysteine-sodium hydroxide improves recovery of viable Mycobacterium avium subsp. paratuberculosis organisms from cultured milk.  

PubMed

Mycobacterium avium subsp. paratuberculosis is shed into the milk and feces of cows with advanced Johne's disease, allowing the transmission of M. avium subsp. paratuberculosis between animals. The objective of this study was to formulate an optimized protocol for the isolation of M. avium subsp. paratuberculosis in milk. The parameters investigated included chemical decontamination with N-acetyl-l-cysteine-sodium hydroxide (NALC-NaOH), alone and in combination with antibiotics (vancomycin, amphotericin B, and nalidixic acid), and the efficacy of solid (Herrold's egg yolk medium [HEY]) and liquid (Bactec 12B and para-JEM) culture media. For each experiment, raw milk samples from a known noninfected cow were inoculated with 10(2) to 10(8) CFU/ml of live M. avium subsp. paratuberculosis organisms. The results indicate that an increased length of exposure to NALC-NaOH from 5 to 30 min and an increased concentration of NaOH from 0.5 to 2.0% did not affect the viability of M. avium subsp. paratuberculosis. Additional treatment of milk samples with the antibiotics following NALC-NaOH treatment decreased the recovery of viable M. avium subsp. paratuberculosis cells more than treatment with NALC-NaOH alone. The Bactec 12B medium was the superior medium of the three evaluated for the isolation of M. avium subsp. paratuberculosis from milk, as it achieved the lowest threshold of detection. The optimal conditions for NALC-NaOH decontamination were determined to be exposure to 1.50% NaOH for 15 min followed by culture in Bactec 12B medium. This study demonstrates that chemical decontamination with NALC-NaOH resulted in a greater recovery of viable M. avium subsp. paratuberculosis cells from milk than from samples treated with hexadecylpyridinium chloride (HPC). Therefore, it is important to optimize milk decontamination protocols to ensure that low concentrations of M. avium subsp. paratuberculosis can be detected. PMID:23637290

Bradner, L; Robbe-Austerman, S; Beitz, D C; Stabel, J R

2013-07-01

340

Changes in Presettlement Forest Composition for Five Areas in the Central Hardwood Forest, 1784-1990  

Microsoft Academic Search

Witness tree tallies from early land surveys show that presettlement forests in eastern Ohio, southwestern Pennsylvania, and north central West Virginia were oak-dominated forests. Quercus alba was dominant by a large margin - at minimum, twice as abundant as Q. velutina, the second ranked species. Acer saccharum and Fagus grandifolia were among the top ten ranked species at each site;

James S. Rentch; Ray R. Hicks

341

Phytotoxicity of American beech leaf leachate to sugar maple seedlings in a greenhouse experiment  

Microsoft Academic Search

In an effort to reexamine the factors that affect codominance of American beech (Fagus grandifolia Ehrh.) and sugar maple (Acer saccharum Marsh.), a greenhouse experiment was conducted to test the potential phytotoxic ef- fects of American beech leaf leachate on sugar maple seedlings. We utilized an experimental protocol that addressed phytotoxic, nutrient, and pH effects by watering seedlings with seven

Elizabeth N. Hane; Steven P. Hamburg; Adelia L. Barber; Jennifer A. Plaut

2003-01-01

342

Nutrient concentrations in roots, leaves and wood of seedling and mature sugar maple and American beech at two contrasting sites  

Microsoft Academic Search

Differences in sensitivity to soil conditions across tree species and developmental stage are important to predicting forest response to environmental change. This study was conducted to compare elemental concentrations in leaves, stems, and roots of (1) sugar maple (Acer saccharum Marsh.) seedlings vs. mature trees and (2) mature sugar maple vs. mature American beech (Fagus grandifolia Ehrh.) in two sites

Byung Bae Park; Ruth D. Yanai

2009-01-01

343

USING ROUNDUP AND OUST TO CONTROL INTERFERING UNDERSTORIES IN ALLEGHENY HARDWOOD STANDS  

Microsoft Academic Search

Allegheny hardwood stands in the Pennsylvania portion of the type frequently contain dense understories of undesirable species such as hayscented fern (Dennstaedtia punctilobula (Michx.) Moore), New York fern (Thelypteris noveboracensis L.), grasses and sedges (Carex spp.), striped maple (Acer pensylvanicum L.) and beech (Fagus grandifolia Ehrh.). Once established, they interfere with the establishment of advance regeneration of desirable species. The

Stephen B. Horsley

344

Late Holocene Decline of Beech Populations in the Central Great Lakes Region: Drought Induced Vegetation Change in a Humid Region  

Microsoft Academic Search

A large decline in beech populations ( Fagus grandifolia) has been well-documented from pollen records in southeastern Michigan and Southern Ontario between 1000 and 600 BP. These records reveal that declines in beech pollen were generally associated with increases in oak ( Quercus) and pine ( Pinus). The beech decline probably extended eastward into western Pennsylvania and New York, although

R. K. Booth; S. T. Jackson; M. Taylor; E. Pendall; V. A. Sousa

2007-01-01

345

The effects of feeding by Oniscus asellus on leaf litter sulfur constituents  

Microsoft Academic Search

Feeding by the isopod, Oniscus asellus, produced changes in the sulfur constituents of leaf litter substrates (Acer negundo, A. saccharum, Fagus grandifolia, Picea rubens, and Tsuga canadensis). Isopod consumption of leaf litter generally accelerated the mineralization of carbon-bonded S and increased the formation of ester sulfate in all substrates. After the isopod egestion of A. negundo leaves, fecal decomposition over

C. R. Morgan; M. J. Mitchell

1987-01-01

346

Variation in the molecular weight of Photobacterium damselae subsp. piscicida antigens when cultured under different conditions in vitro  

PubMed Central

The antigenicity of Photobacterium damselae (Ph. d.) subsp. piscicida, cultured in four different growth media [tryptone soya broth (TSB), glucose-rich medium (GRM), iron-depleted TSB (TSB + IR-), and iron-depleted GRM (GRM + IR-)] was compared by enzyme-linked immunosorbent assay (ELISA) and Western blot analysis using sera obtained from sea bass (Dicentrarchus labrax) raised against live or heat-killed Ph. d. subsp. piscicida. The antigenic expression of Ph. d. subsp. piscicida was found to differ depending on the culture medium used. A significantly higher antibody response was obtained with iron-depleted bacteria by ELISA compared with non-iron depleted bacteria obtained from the sera of sea bass raised against live Ph. d. subsp. piscicida. The sera from sea bass raised against live bacteria showed a band at 22 kDa in bacteria cultured in TSB + IR- or GRM+ IR- when bacteria that had been freshly isolated from fish were used for the screening, while bands at 24 and 47 kDa were observed with bacteria cultured in TSB or GRM. When bacteria were passaged several times on tryptic soya agar prior to culturing in the four different media, only bands at 24 and 47 kDa were recognized, regardless of the medium used to culture the bacteria. It would appear that the molecular weight of Ph. d. subsp. piscicida antigens change in the presence of iron restriction, and sera from sea bass infected with live bacteria are able to detect epitopes on the antigens after this shift in molecular weight. PMID:17679772

Thompson, Kim D.; Volpatti, Donatella; Galeotti, Marco; Adams, A.

2007-01-01

347

In Silico Identification of Epitopes in Mycobacterium avium subsp. paratuberculosis Proteins That Were Upregulated under Stress Conditions  

PubMed Central

Johne's disease in ruminants is caused by Mycobacterium avium subsp. paratuberculosis. Diagnosis of M. avium subsp. paratuberculosis infection is difficult, especially in the early stages. To date, ideal antigen candidates are not available for efficient immunization or immunodiagnosis. This study reports the in silico selection and subsequent analysis of epitopes of M. avium subsp. paratuberculosis proteins that were found to be upregulated under stress conditions as a means to identify immunogenic candidate proteins. Previous studies have reported differential regulation of proteins when M. avium subsp. paratuberculosis is exposed to stressors which induce a response similar to dormancy. Dormancy may be involved in evading host defense mechanisms, and the host may also mount an immune response against these proteins. Twenty-five M. avium subsp. paratuberculosis proteins that were previously identified as being upregulated under in vitro stress conditions were analyzed for B and T cell epitopes by use of the prediction tools at the Immune Epitope Database and Analysis Resource. Major histocompatibility complex class I T cell epitopes were predicted using an artificial neural network method, and class II T cell epitopes were predicted using the consensus method. Conformational B cell epitopes were predicted from the relevant three-dimensional structure template for each protein. Based on the greatest number of predicted epitopes, eight proteins (MAP2698c [encoded by desA2], MAP2312c [encoded by fadE19], MAP3651c [encoded by fadE3_2], MAP2872c [encoded by fabG5_2], MAP3523c [encoded by oxcA], MAP0187c [encoded by sodA], and the hypothetical proteins MAP3567 and MAP1168c) were identified as potential candidates for study of antibody- and cell-mediated immune responses within infected hosts. PMID:22496492

Gurung, Ratna B.; Purdie, Auriol C.; Begg, Douglas J.

2012-01-01

348

Bioactive alkaloids produced by Pseudomonas brassicacearum subsp. Neoaurantiaca, an endophytic bacterium from Salvia miltiorrhiza.  

PubMed

Eleven compounds were isolated from the culture of an endophytic bacterium Pseudomonas brassicacearum subsp. Neoaurantiaca in Salvia miltiorrhiza Bunge. Their structures were elucidated by spectroscopic methods as cyclo-(Gly-L-Ala) (1), cyclo-(L-Ala-L-Ala) (2), cyclo-(L-Pro-Gly) (3), cyclo-(L-Pro-L-Ser) (4), cyclo-(L-Ala-trans-4-hydroxy-L-Pro) (5), cyclo-(L-Val-L-Pro) (6), cyclo-(Gly-L-Tyr) (7), cyclo-(L-Ala-L-Tyr) (8), cyclo-(L-Tyr-trans-4-hydroxy-L-Pro) (9), 3-methylhydantoin (10) and 2-piperidinone (11). All these compounds were isolated from this bacterium for the first time. The brine shrimp lethality, antifungal and antibacterial activities of these compounds were evaluated. The results indicated that some cyclodipeptides may play an important role in plant-bacteria interactions. PMID:22765159

Li, Xiao-Jun; Tang, Hao-Yu; Duan, Jia-Li; Gao, Jin-Ming; Xue, Quan-Hong

2013-03-01

349

Composition and antimicrobial activity of the essential oil of Cistus creticus subsp. eriocephalus.  

PubMed

The chemical composition of the essential oil of the leaves of Cistus creticus subsp. eriocephalus (Viv.) Greuter & Burdet, (Cistaceae), was investigated by GC/MS. Thirty-nine components were identified, representing 73.9% (based on % total peak area by GC) of the oil composition. The main components of the oil were alpha-cadinene (6.5%), delta-cadinene (5.6%), viridiflorol (5.4%), bulnesol (6.3%), ledol (3.8%), alpha-copaene (3.8%), beta-selinene (3.4%), cubenene (3.3%), manoyl oxide (9.9%) and 13-epi-manoyl oxide (3.4%). Antibacterial studies were carried out in vitro against Gram-positive and Gram-negative organisms. PMID:9342956

Demetzos, C; Katerinopoulos, H; Kouvarakis, A; Stratigakis, N; Loukis, A; Ekonomakis, C; Spiliotis, V; Tsaknis, J

1997-10-01

350

Biological Role of Pigment Production for the Bacterial Phytopathogen Pantoea stewartii subsp. stewartii  

PubMed Central

Pantoea stewartii subsp. stewartii, the causal agent of Stewart's wilt of sweet corn, produces a yellow carotenoid pigment. A nonpigmented mutant was selected from a bank of mutants generated by random transposon mutagenesis. The transposon insertion site was mapped to the crtB gene, encoding a putative phytoene synthase, an enzyme involved in the early steps of carotenoid biosynthesis. We demonstrate here that the carotenoid pigment imparts protection against UV radiation and also contributes to the complete antioxidant pathway of P. stewartii. Moreover, production of this pigment is regulated by the EsaI/EsaR quorum-sensing system and significantly contributes to the virulence of the pathogen in planta. PMID:22820327

Mohammadi, Mojtaba; Burbank, Lindsey

2012-01-01

351

Citrate can partially replace carbon dioxide required for growth of Lactococcus lactis subsp. lactis biovar diacetylactis.  

PubMed

Lactococcus lactis subsp. lactis biovar diacetylactis was grown as batch cultures on a chemically defined medium. No growth was observed when the cultures were sparged with pure nitrogen (1.3 l l-1 min-1) whereas the cultures displayed exponential growth in the presence of minute amounts of carbon dioxide (0.035 mol-% of the inlet gas). However, in the former case, the addition of citrate restored growth. This suggested that oxaloacetate required for aspartate biosynthesis can be formed by the carboxylation of pyruvate or by citrate catabolism. When the cultures were heavily sparged with nitrogen (2.6 l l-1 min-1), no growth was observed even in the presence of citrate. This indicated that growth in these conditions was repressed by the absence of carbon dioxide required in some other biosynthetic reaction than in the carboxylation of pyruvate leading to oxaloacetate/aspartate biosynthesis. PMID:10792674

Henriksen, C M; Curic, M; Nilsson, D

2000-05-01

352

Cytolytic peptide fragments of Cyt1Aa from Bacillus thuringiensis subsp. israelensis.  

PubMed

Cyt1Aa is the major and most active component of the parasporal crystal of the Gram-positive soil entomopathogenic bacterium Bacillus thuringiensis subsp. israelensis. The Cyt1Aa protoxin exhibits some hemolytic and cytolytic activity. However, highly active 22-25 kDa toxins are obtained after proteolysis of Cyt1Aa from both the N- and the C-termini. As shown in this study, preliminary binding of the protoxin to polylamellary liposomes or partial denaturation of Cyt1Aa and further processing by several exogenous proteases yielded short 4.9-11.5 kDa cytolytic peptide fragments of Cyt1Aa. The shortest 51 amino acid peptide was obtained after pre-incubation of Cyt1Aa with SDS and proteolysis with proteinase K. This peptide was purified, identified as the Ile87-Asp137 fragment of Cyt1Aa and was shown to exhibit more than 30 % hemolysis of rabbit erythrocytes. PMID:22875467

Nisnevitch, Marina; Nikonov, Svetlana; Nitzan, Yeshayahu

2013-03-01

353

Infection of the thyroid gland caused by Campylobacter fetus subsp. fetus.  

PubMed

We report what we consider to be the first case of an abscess of the thyroid gland due to Campylobacter fetus subsp. fetus (C. fetus) in a patient suffering from hyperthyroidism. C. fetus is known as a rare and opportunistic pathogen in humans, causing a broad variety of systemic infections. Acquisition by humans is thought to occur through contact with animals or animal products and to start as a gastro-intestinal colonization. The detection of C. fetus in stool is challenging, since culture efforts are generally directed in order to fulfil growth requirements of C.jejuni, a much more common enteric pathogen. Detection of C. fetus in non-stool samples is even more challenging since routine culture doesn't imply prolonged incubation (>72h), selective media and microaerophilic conditions. It is therefore not unlikely that human infections caused by C. fetus occur more often than generally assumed. PMID:17547296

Goegebuer, T; Verhaeghe, J P; Verlinde, A; De Laere, E; Surmont, I

2007-01-01

354

Quantification of Mycobacterium avium subsp. paratuberculosis (MAP) survival in monocyte-derived macrophages.  

PubMed

Real-time PCR assays were developed to quantitate Mycobacterium avium subsp. paratuberculosis (MAP) in bovine monocyte-derived macrophages. We measured the absolute number of both host cells and bacteria in in vitro challenge assays. Results obtained from real-time quantitative PCR (qPCR) DNA copy counts were compared to visual quantitation of fluorescent-stained MAP in macrophages. Conclusions from our original visual analysis were supported by the second (qPCR) methodology; however, the qPCR assay proved to be more consistent between samples and was easier to perform. There was a strain-to-strain difference in growth curves between fluorescent quantitation (FQ) and qPCR that we believe to be a consequence of bacterial growth characteristics in FQ. In summary, real-time PCR assays provided a more accurate and precise method for evaluating intracellular growth dynamics when comparing strains of MAP. PMID:20832125

Mitchell, Rebecca M; Gollnick, Nicole S; Sreevatsan, Srinand; Russell, David G; Schukken, Ynte H

2011-01-01

355

[Dissociation of Pectobacterium carotovorum subsp. carotovorumrelated to the changes in the cell wall lipopolysaccharide].  

PubMed

It is shown for the first time that population heterogeneity of Pectobacterium carotovorum subsp. carotovorum is applicable to a wide range of strains and therefore is a universal characteristic. Using the method of specific selection with the help of carotovoricins which are identical to the phage tails a set of population dissociants of different types was obtained, due to the fact that S-LPS is the part of the cell wall which contains their attachment sites. It was determined that changes in S-lipopolysaccharides lead to the formation of SR-, R-forms of P. carotovorum. A suggestion is made that the changes in the surface structures of dissociants have a significant impact on secretion types II and III--the main pathogenicity factor of some bacteria. The results presented are a prerequisite for studying the direction, the reasons for dissociation process and its impact on the pathogenicity of P. carotovorum. PMID:22545443

Tovkach, F I; Romaniuk, L V; Gorb, T E; Ostapchuk, A N; Muchnik, F V

2012-01-01

356

Antioxidant and antiproliferative activity of Hypericum hircinum L. subsp. majus (Aiton) N. Robson essential oil.  

PubMed

This study was undertaken to assess the antioxidant and antiproliferative potential of the essential oil of Hypericum hircinum L. subsp. majus (Aiton) N. Robson. Analysis of the oil composition revealed that sesquiterpene hydrocarbons (69.3%) dominate, cis-?-guaiene, ?-selinene and (E)-caryophyllene being the most representative. Significant values of antioxidant activity were found using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays. The essential oil revealed antiproliferative activity as evaluated on human glioblastoma (T98G), human prostatic adenocarcinoma (PC3), human squamous carcinoma (A431) and mouse melanoma (B16-F1) tumour cell lines by MTT assay. PMID:22480321

Quassinti, Luana; Lupidi, Giulio; Maggi, Filippo; Sagratini, Gianni; Papa, Fabrizio; Vittori, Sauro; Bianco, Armandodoriano; Bramucci, Massimo

2013-01-01

357

Two new species of Lactarius associated with Alnus acuminata subsp. arguta in Mexico.  

PubMed

In pure stands of Alnus acuminata subsp. arguta trees from Sierra Norte de Puebla (central Mexico) two undescribed ectomycorrhizal species of Lactarius were discovered. Distinction of the two new species is based on morphological characters and supported with phylogenetic analyses of the nuclear ribosomal DNA ITS region and part of the gene that encodes for the second largest subunit of RNA polymerase II (rpb2). The phylogenies inferred recovered the two species in different clades strongly supported by posterior probabilities and bootstrap values. The new Lactarius species are recognized as part of the assemblage of ectomycorrhizal fungi associated with Alnus acuminata. Information about these taxa includes the morphological variation achieved along 16 monitories 2010-2013. Descriptions are provided. They are accompanied by photos including SEM photomicrographs of basidiospores and information on differences between them and other related taxa from Europe and the United States. PMID:24895428

Montoya, Leticia; Bandala, Victor M; Garay, Edith

2014-01-01

358

Development of Loop-Mediated Isothermal Amplification for Detection of Leifsonia xyli subsp. xyli in Sugarcane  

PubMed Central

Ratoon stunt, caused by the xylem-limited coryneform bacterium Leifsonia xyli subsp. xyli (Lxx), is a deep bacteriosis and prevalent in most of sugarcane-producing countries. Based on loop-mediated isothermal amplification (LAMP), we developed a method for detecting Lxx. The major advantages of the LAMP method are visual judgment by color and time saving with only 60?min for identification of Lxx and without the need for costly PCR apparatus and gel scanner. In the present study, positive and negative samples detected by the LAMP method were clearly distinguishable. When total DNA extracted from internode juice was used as the template, the sensitivity of LAMP was 10 times higher than that of the conventional PCR detection. The LAMP assay is a highly specific, rapid, and sensitive method for the diagnosis of ratoon stunt caused by Lxx in sugarcane. This is the first report of LAMP-based assay for the detection of Lxx in sugarcane. PMID:23710444

Liu, Jing; Guo, Jinlong; Chen, Rukai; Grisham, Michael Paul

2013-01-01

359

Mechanism of inhibited growth of Bacillus pumilus by Propionibacterium freudenreichii subsp. shermanii.  

PubMed

Physiological studies were conducted in an attempt to elucidate the mechanism of inhibition of Bacillus pumilus by Propionibacterium freudenreichii subsp. shermanii. Inhibition of B. pumilus by P. shermanii occurred in media supplemented with 1% glucose, indicating that glucose utilization by the latter bacterium was not responsible for growth inhibition of the former bacterium. The medium pH in which P. shermanii inhibited the growth of B. pumilus was 4.3. Propionic acid was positively identified in the culture medium in which B. pumilus was inhibited by P. shermanii. The presence of propionic acid and a low medium pH may account for the inhibition of B. pumilus by P. shermanii. Sodium lactate concentrations of 0.8-1.0% were essential for the continuous growth of and propionic acid production by P. shermanii. Thus, use of P. shermanii to inhibit B. pumilus in foods would likely require a lactate source. PMID:8060789

Marshall, D L; Odame-Darkwah, J K

1994-04-01

360

Fermentation performance of an exopolysaccharide-producing strain of Lactobacillus delbrueckii subsp. bulgaricus.  

PubMed

The formation of exopolysaccharide (EPS) and extracellular metabolites was studied in a strain of Lactobacillus delbrueckii subsp. bulgaricus (NCFB 2483), grown under batch culture conditions in a semi-defined medium incorporating lactose and casein hydrolysate. Performance parameters were derived from the fermentation data, and kinetic models were applied in order to describe the production of EPS, extracellular metabolites, and biomass produced. Lactose was split intracellularly, with the resultant galactose being exported from the cell, and the glucose being metabolised further to EPS and lactic acid. Production of EPS, lactate, and galactose was closely growth-associated and followed a pattern of primary kinetics. A marginally lower galactose level relative to the modelled levels throughout most of the time course of the fermentation suggests that not all galactose is exported from the cell, and that a low level of flux to other metabolites, such as EPS, might exist. PMID:14618406

Welman, A D; Maddox, I S

2003-11-01

361

Exopolysaccharide and extracellular metabolite production by Lactobacillus delbrueckii subsp. bulgaricus, grown on lactose in continuous culture.  

PubMed

Lactobacillus delbrueckii subsp. bulgaricus NCFB 2483, when grown on lactose in continuous culture, showed increasing specific yields and volumetric productivities of exopolysaccharide (EPS) with increasing dilution rate. Specific and volumetric productivities of lactate and galactose, as extracellular metabolites, increased in response to the incremental changes in the dilution rate up to 0.4 h(-1). Elevated Y(p/s) values determined for EPS (0.025 g EPS x g lactose(-1)) at the dilution rates of 0.3 h(-1)-0.4 h(-1), relative to those determined at lower dilution rates, suggest a diversion of carbon flux towards EPS being associated with the higher rates of growth. PMID:14571975

Welman, Alan; Maddox, Ian; Archer, Richard

2003-09-01

362

Spread of Mycobacterium avium subsp. paratuberculosis through soil and grass on a mouflon (Ovis aries) pasture.  

PubMed

The aims of this study were to describe spatial contamination of the environment on a mouflon pasture, as well as to assess the contamination of grass and roots after surface contamination and in depth contamination with feces and buried tissues from animals infected with Mycobacterium avium subsp. paratuberculosis (M. a. paratuberculosis). Samples of soil, roots, and aerial parts of plants were collected from different locations inside the mouflon pasture, and one control sample site was chosen outside the area where the animals are living. M. a. paratuberculosis DNA was present in all the examined sites and was more often detected in roots than in soil. DNA was detected at up to 80cm of depth and was spatially more widespread than the initial hypothesis of M. a. paratuberculosis leaching vertically into deeper layers of soil. This study broadens our knowledge of the spread and persistence of M. a. paratuberculosis in an environment with highly infected animals. PMID:24880776

Kaevska, Marija; Lvoncik, S; Lamka, J; Pavlik, I; Slana, I

2014-10-01

363

Results of Multiple Diagnostic Tests for Mycobacterium avium subsp. paratuberculosis in Patients with Inflammatory Bowel Disease and in Controls  

PubMed Central

Mycobacterium avium subsp. paratuberculosis has been incriminated as a cause of Crohn's disease (CD); however, studies to date have been relatively small and generally only used a single diagnostic assay. The objective of the study was to reexamine the association of M. avium subsp. paratuberculosis and CD using multiple diagnostic tests. Five methods were used to detect M. avium subsp. paratuberculosis infections in 439 inflammatory bowel disease (IBD) patients and 324 control subjects in the United States and Denmark. Most assays were adaptations of diagnostic tests for this infection performed routinely on animals. PCR for IS900, a genetic element unique to M. avium subsp. paratuberculosis, was positive significantly more often on resected bowel and lymph node tissues from CD patients (19.0%) and ulcerative colitis (UC) patients (26.2%) than from controls (6.3%) (P < 0.05). Positive IS900 PCR results occurred more often in U.S. than in Danish IBD patients, 32.0 versus 13.3% (P = 0.025). The majority of Danish patients were bacillus Calmette-Gurin (Mycobacterium bovis BCG) vaccinated (CD, 77.5%; UC, 86.6%; controls, 83.0%) whereas none of the U.S. patients with IBD and only 2% of U.S. controls were vaccinated. Among Danish IBD patients, positive PCR findings were four times more common among subjects who were not BCG vaccinated (33.3%) than among BCG vaccinates (8.8%, P = 0.02). Culture of the same tissues tested by PCR using modified BACTEC 12B medium failed to grow M. avium subsp. paratuberculosis from patients or controls. U.S. CD patients had the highest serological evidence (enzyme-linked immunosorbent assay [ELISA] for serum antibodies) of M. avium subsp. paratuberculosis infection (20.7% of patients positive) which was higher than for all UC patients studied (6.1%) or healthy controls (3.8%, P < 0.005). Among Danish patients alone, however, no significant differences in rates of ELISA-positive results among CD, UC, or control patients were found. For 181 study subjects, both IS900 PCR and ELISA were performed. Although 11 were ELISA positive and 36 were PCR positive, in no instance was a patient positive by both tests, suggesting that these states are mutually exclusive. Evaluation of cytokine-mediated immune responses of IBD patients was complicated by the influence of immunosuppressive therapy given most IBD patients. Gamma interferon (IFN-?) release by peripheral blood leukocytes after M. avium purified protein derivative PPD antigen stimulation showed significantly lower responses in CD patients than in UC patients or controls in both U.S. (by ex vivo assay) and Danish (by in vitro assay) populations (P < 0.05). Interleukin-5 responses were not different among CD, UC, or control groups. Collectively, the PCR, ELISA, and IFN-? tests for M. avium subsp. paratuberculosis together with the unexpected observation that BCG vaccination influenced M. avium subsp. paratuberculosis detection, lead us to conclude that M. avium subsp. paratuberculosis, or some similarly fastidious mycobacterial species, infects at least a subset of IBD patients. Whether the infection is primary (causal) or secondary, it may contribute to the etiopathogenesis of IBD. PMID:11101567

Collins, Michael T.; Lisby, Gorm; Moser, Claus; Chicks, Debra; Christensen, Steen; Reichelderfer, Mark; H?iby, Niels; Harms, Bruce A.; Thomsen, Ole ?.; Skibsted, Ulrik; Binder, Vibeke

2000-01-01

364

Comparative chemical composition and antioxidant activity of Calamintha nepeta (L.) Savi subsp. glandulosa (Req.) Nyman and Calamintha grandiflora (L.) Moench (Labiatae).  

PubMed

The two studied Calamintha species showed different polyphenolic content and sterol composition. Calamintha grandiflora possessed twice the polyphenolic content of Calamintha nepeta subsp. glandulosa, while the latter contained a higher number of sterols. Among them, stigmast-5-en-3?-ol was found to be the major constituent. The methanolic extract of C. grandiflora was more potent than the C. nepeta subsp. glandulosa methanolic extract in a DPPH assay, while the activity of the C. grandiflora EtOAc fraction was weaker than its C. nepeta subsp. glandulosa counterpart. Fractions of C. nepeta subsp. glandulosa showed higher activity using a ?-carotene bleaching test. The petrol ether fraction of C. grandiflora showed significant inhibition of NO production. PMID:21861645

Conforti, Filomena; Marrelli, Mariangela; Statti, Giancarlo; Menichini, Federica; Uzunov, Dimitar; Solimene, Umberto; Menichini, Francesco

2012-01-01

365

Long Lasting Persistence of Bacillus thuringiensis Subsp. israelensis (Bti) in Mosquito Natural Habitats  

PubMed Central

Background The detrimental effects of chemical insecticides on the environment and human health have lead to the call for biological alternatives. Today, one of the most promising solutions is the use of spray formulations based on Bacillus thuringiensis subsp. israelensis (Bti) in insect control programs. As a result, the amounts of Bti spread in the environment are expected to increase worldwide, whilst the common belief that commercial Bti is easily cleared from the ecosystem has not yet been clearly established. Methodology/Main Findings In this study, we aimed to determine the nature and origin of the high toxicity toward mosquito larvae found in decaying leaf litter collected in several natural mosquito breeding sites in the Rhne-Alpes region. From the toxic fraction of the leaf litter, we isolated B. cereus-like bacteria that were further characterized as B. thuringiensis subsp. israelensis using PCR amplification of specific toxin genes. Immunological analysis of these Bti strains showed that they belong to the H14 group. We finally used amplified length polymorphism (AFLP) markers to show that the strains isolated from the leaf litter were closely related to those present in the commercial insecticide used for field application, and differed from natural worldwide genotypes. Conclusions/Significance Our results raise the issue of the persistence, potential proliferation and environmental accumulation of human-spread Bti in natural mosquito habitats. Such Bti environmental persistence may lengthen the exposure time of insects to this bio-insecticide, thereby increasing the risk of resistance acquisition in target insects, and of a negative impact on non-target insects. PMID:18941501

Tilquin, Mathieu; Paris, Margot; Reynaud, Stphane; Despres, Laurence; Ravanel, Patrick; Geremia, Roberto A.; Gury, Jrme

2008-01-01

366

Genetic and Physiological Responses of Bifidobacterium animalis subsp. lactis to Hydrogen Peroxide Stress  

PubMed Central

Consumer interest in probiotic bifidobacteria is increasing, but industry efforts to secure high cell viability in foods is undermined by these anaerobes' sensitivity to oxidative stress. To address this limitation, we investigated genetic and physiological responses of two fully sequenced Bifidobacterium animalis subsp. lactis strains, BL-04 and DSM 10140, to hydrogen peroxide (H2O2) stress. Although the genome sequences for these strains are highly clonal, prior work showed that they differ in both intrinsic and inducible H2O2 resistance. Transcriptome analysis of early-stationary-phase cells exposed to a sublethal H2O2 concentration detected significant (P < 0.05) changes in expression of 138 genes in strain BL-04 after 5 min and 27 genes after 20 min. Surprisingly, no significant changes in gene expression were detected in DSM 10140 at either time. Genomic data suggested that differences in H2O2 stress resistance might be due to a mutation in a BL-04 gene encoding long-chain fatty acid coenzyme A (CoA) ligase. To explore this possibility, membrane fatty acids were isolated and analyzed by gas chromatography-mass spectrometry (GC-MS). Results confirmed that the strains had significantly different lipid profiles: the BL-04 membrane contained higher percentages of C14:0 and C16:0 and lower percentages of C18:1n9. Alteration of the DSM 10140 membrane lipid composition using modified growth medium to more closely mimic that of BL-04 yielded cells that showed increased intrinsic resistance to lethal H2O2 challenge but did not display an inducible H2O2 stress response. The results show that deliberate stress induction or membrane lipid modification can be employed to significantly improve H2O2 resistance in B. animalis subsp. lactis strains. PMID:23772066

Oberg, Taylor S.; Ward, Robert E.; Steele, James L.

2013-01-01

367

Physical and genetic map of the chromosome of Lactococcus lactis subsp. lactis IL1403.  

PubMed Central

A combined physical and genetic map of the chromosome of Lactococcus lactis subsp. lactis IL1403 was determined. We constructed a restriction map for the NotI, ApaI, and SmaI enzymes. The order of the restriction fragments was determined by using the randomly integrative plasmid pRL1 and by performing indirect end-labeling experiments. The strain IL1403 chromosome was found to be circular and 2,420 kb in size. A total of 24 chromosomal markers were mapped on the chromosome by performing hybridization experiments with gene probes for L. lactis and various other bacteria. Integration of pRC1-derived plasmids via homologous recombination allowed more precise location of some lactococcal genes and allowed us to determine the orientation of these genes on the chromosome. Recurrent sequences, such as insertion elements and rRNA gene (rrn) clusters, were also mapped. At least seven copies of IS1076 were present and were located on 50% of the chromosome. In contrast, no copy of ISS1RS was detected. Six ribosomal operons were found on the strain IL1403 chromosome; five were located on 16% of the chromosome and were transcribed in the same direction. A comparison of the physical maps of L. lactis subsp. lactis IL1403 and DL11 showed that these two strains are closely related and that the variable regions are located mainly near the rrn gene clusters. In contrast, despite major restriction pattern dissimilarities between L. lactis IL1403 and MG1363, the overall genetic organization of the genome seems to be conserved between these two strains. Images PMID:1328163

Le Bourgeois, P; Lautier, M; Mata, M; Ritzenthaler, P

1992-01-01

368

Identification and characterization of three previously undescribed crystal proteins from Bacillus thuringiensis subsp. jegathesan.  

PubMed

The total protoxin complement in the parasporal body of mosquitocidal strain, Bacillus thuringiensis subsp. jegathesan 367, was determined by use of a polyacrylamide gel block coupled to mass spectrometry. A total of eight protoxins were identified from this strain, including five reported protoxins (Cry11Ba, Cry19Aa, Cry24Aa, Cry25Aa, and Cyt2Bb), as well as three previously undescribed (Cry30Ca, Cry60Aa, and Cry60Ba) in this isolate. It was interesting that the encoding genes of three new protoxins existed as cry30Ca-gap-orf2 and cry60Ba-gap-cry60Aa. The cry30Ca and a downstream orf2 gene were oriented in the same direction and separated by 114 bp, and cry60Ba was located 156 bp upstream from and in the same orientation to cry60Aa. The three new protoxin genes were cloned from B. thuringiensis subsp. jegathesan and expressed in an acrystalliferous strain under the control of cyt1A gene promoters and the STAB-SD stabilizer sequence. Recombinant strain containing only cry30Ca did not produce visible inclusion under microscope observation, while that containing both cry30Ca and orf2 could produce large inclusions. Cry60Aa and Cry60Ba synthesized either alone or together in the acrystalliferous host could yield large inclusions. In bioassays using the fourth-instar larvae of Culex quinquefasciatus, Cry60Aa and Cry60Ba alone or together had estimated 50% lethal concentrations of 2.9 to 7.9 ?g/ml; however, Cry30Ca with or without ORF2 was not toxic to this mosquito. PMID:23524673

Sun, Yunjun; Zhao, Qiang; Xia, Liqiu; Ding, Xuezhi; Hu, Quanfang; Federici, Brian A; Park, Hyun-Woo

2013-06-01

369

Host responses to the pathogen Mycobacterium avium subsp. paratuberculosis and beneficial microbes exhibit host sex specificity.  

PubMed

Differences between microbial pathogenesis in male and female hosts are well characterized in disease conditions connected to sexual transmission. However, limited biological insight is available on variances attributed to sex specificity in host-microbe interactions, and it is most often a minimized variable outside these transmission events. In this work, we studied two gut microbes-a pathogen, Mycobacterium avium subsp. paratuberculosis, and a probiotic, Lactobacillus animalis NP-51-and the interaction between each agent and the male and female gastrointestinal systems. This trial was conducted in BALB/c mice (n=5 per experimental group and per sex at a given time point), with analysis at four time points over 180 days. Host responses to M.avium subsp. paratuberculosis and L. animalis were sensitive to sex. Cytokines that were significantly different (P ? 0.05) betweenthe sexes included interleukin-1?/? (IL-1?/?), IL-17, IL-6, IL-10, IL-12, and gamma interferon (IFN-) and were dependent on experimental conditions. However, granulocyte-macrophage colony-stimulating factor (GM-CSF), vascular endothelial growth factor (VEGF), and IL-13/23 showed no sex specificity. A metabolomics study indicated a 0.5- to 2.0-fold (log2 scale) increase in short-chain fatty acids (butyrate and acetate) in males and greater increases in o-phosphocholine or histidine from female colon tissues; variances distinct to each sex were observed with age or long-term probiotic consumption. Two genera, Staphylococcus and Roseburia, were consistently overrepresented in females compared to males; other species were specific to one sex but fluctuated depending on experimental conditions. The differences observed suggest that male and female gut tissues and microbiota respond to newly introduced microorganisms differently and that gut-associated microorganisms with host immune system responses and metabolic activity are supported by biology distinct to the host sex. PMID:24814797

Karunasena, Enusha; McMahon, K Wyatt; Chang, David; Brashears, Mindy M

2014-08-01

370

In vivo morphological and antigenic characteristics of Photobacterium damselae subsp. piscicida  

PubMed Central

The present study was conducted to examine the morphology and antigenicity of Photobacterium damselae subsp. piscicida by culturing the bacterium in vivo in the peritoneal cavity of sea bass (Dicentrarchus labrax) within dialysis bags with either a low molecular weight (LMW) cut-off of 25 kDa or a high molecular weight (HMW) cut-off of 300 kDa. Differences were observed in the growth rate between the bacteria cultured in vivo or in vitro. Bacteria cultured in vivo were smaller and produced a capsular layer, which was more prominent in bacteria cultured in the HMW bag. Antigenicity was examined by Western blot analysis using sera from sea bass injected with live Ph. d. subsp. piscicida. The sera recognised bands at 45 and 20 kDa in bacteria cultured in vivo in the LMW bag. Bacteria cultured in vivo in the HMW bag did not express the 45 kDa band when whole cell extracts were examined, although the antigen was present in their extracellular products. In addition, these bacteria had a band at 18 kDa rather than 20 kDa. Differences in glycoprotein were also evident between bacteria cultured in vitro and in vivo. Bacteria cultured in vitro in LMW and HMW bags displayed a single 26 kDa band. Bacteria cultured in the LMW bag in vivo displayed bands at 26 and 27 kDa, while bacteria cultured in vivo in the HMW bag possessed only the 27 kDa band. These bands may represent sialic acid. The significance of the changes observed in the bacterium's structure and antigenicity when cultured in vivo is discussed. PMID:18487938

Thompson, Kim D.; Volpatti, Donatella; Galeotti, Marco; Adams, A.

2008-01-01

371

Molecular Epidemiology of Mycobacterium avium subsp. paratuberculosis Isolates Recovered from Wild Animal Species  

PubMed Central

Mycobacterial isolates were obtained by radiometric culture from 33 different species of captive or free-ranging animals (n = 106) and environmental sources (n = 3) from six geographic zones within the United States. The identities of all 109 isolates were confirmed by using mycobactin J dependence and characterization of five well-defined molecular markers, including two integration loci of IS900 (loci L1 and L9), one Mycobacterium avium subsp. paratuberculosis (M. paratuberculosis)-specific sequence (locus 251), and one M. avium subsp. avium-specific marker (IS1245), as well as hsp65 and IS1311 restriction endonuclease analyses. Seventy-six acid-fast isolates were identified as M. paratuberculosis, 15 were identified as belonging to the M. avium-M. intracellulare complex (but not M. paratuberculosis), and the remaining 18 were identified as mycobacteria outside the M. avium-M. intracellulare complex. Fingerprinting by multiplex PCR for IS900 integration loci clustered 67 of the 76 M. paratuberculosis strains into a single clade (designated clade A18) and had a Simpson's diversity index (D) of 0.53. In contrast, sequence-based characterization of a recently identified M. paratuberculosis short sequence repeat (SSR) region enabled the differentiation of the M. paratuberculosis isolates in clade A18 into seven distinct alleles (D = 0.75). The analysis revealed eight subtypes among the 33 species of animals, suggesting the interspecies transmission of specific strains. Taken together, the results of our analyses demonstrate that SSR analysis enables the genetic characterization of M. paratuberculosis isolates from different host species and provide evidence for the host specificity of some M. paratuberculosis strains as well as sharing of strains between wild and domesticated animal species. PMID:15071028

Motiwala, Alifiya S.; Amonsin, Alongkorn; Strother, Megan; Manning, Elizabeth J. B.; Kapur, Vivek; Sreevatsan, Srinand

2004-01-01

372

Detection and Verification of Mycobacterium avium subsp. paratuberculosis in Fresh Ileocolonic Mucosal Biopsy Specimens from Individuals with and without Crohn's Disease  

PubMed Central

Mycobacterium avium subsp. paratuberculosis is a robust and phenotypically versatile pathogen which causes chronic inflammation of the intestine in many species, including primates. M. avium subsp. paratuberculosis infection is widespread in domestic livestock and is present in retail pasteurized cows' milk in the United Kingdom and, potentially, elsewhere. Water supplies are also at risk. The involvement of M. avium subsp. paratuberculosis in Crohn's disease (CD) in humans has been uncertain because of the substantial difficulties in detecting this pathogen. In its Ziehl-Neelsen staining-negative form, M. avium subsp. paratuberculosis is highly resistant to chemical and enzymatic lysis. The present study describes the development of optimized sample processing and DNA extraction procedures with fresh human intestinal mucosal biopsy specimens which ensure access to M. avium subsp. paratuberculosis DNA and maximize detection of these low-abundance pathogens. Also described are two nested PCR methodologies targeted at IS900, designated IS900[L/AV] and IS900[TJ1-4], which are uniquely specific for IS900. Detection of M. avium subsp. paratuberculosis in mucosal biopsy specimens was also evaluated by using mycobacterial growth indicator tube (MGIT) cultures (Becton Dickinson). IS900[L/AV] PCR detected M. avium subsp. paratuberculosis in 34 of 37 (92%) patients with CD and in 9 of 34 (26%) controls without CD (noninflammatory bowel disease [nIBD] controls) (P = 0.0002; odds ratio = 3.47). M. avium subsp. paratuberculosis was detected by IS900[L/AV] PCR in MGIT cultures after 14 to 88 weeks of incubation in 14 of 33 (42%) CD patients and 3 of 33 (9%) nIBD controls (P = 0.0019; odds ratio = 4.66). Nine of 15 (60%) MGIT cultures of specimens from CD patients incubated for more than 38 weeks were positive for M. avium subsp. paratuberculosis. In each case the identity of IS900 from M. avium subsp. paratuberculosis was verified by amplicon sequencing. The rate of detection of M. avium subsp. paratuberculosis in individuals with CD is highly significant and implicates this chronic enteric pathogen in disease causation. PMID:12843021

Bull, Tim J.; McMinn, Elizabeth J.; Sidi-Boumedine, Karim; Skull, Angela; Durkin, Damien; Neild, Penny; Rhodes, Glenn; Pickup, Roger; Hermon-Taylor, John

2003-01-01

373

kdgR Ecc Negatively Regulates Genes for Pectinases, Cellulase, Protease, Harpin Ecc , and a Global RNA Regulator in Erwinia carotovora subsp. carotovora  

Microsoft Academic Search

Erwinia carotovora subsp. carotovora produces extracellular pectate lyase (Pel), polygalacturonase (Peh), cellulase (Cel), and protease (Prt). The concerted actions of these enzymes largely determine the virulence of this plant-pathogenic bacterium. E. carotovora subsp. carotovora also produces HarpinEcc, the elicitor of the hypersensitive reaction. We document here that KdgREcc (Kdg, 2-keto-3-deoxygluconate; KdgR, general re- pressor of genes involved in pectin and

YANG LIU; GUOQIAO JIANG; YAYA CUI; ASITA MUKHERJEE; WEI LEI MA; ARUN K. CHATTERJEE

1999-01-01

374

Ecological interaction of a biocontrol Pseudomonas fluorescens strain producing 2,4-diacetylphloroglucinol with the soft rot potato pathogen Erwinia carotovora subsp. atroseptica  

Microsoft Academic Search

Erwinia carotovora subspecies atroseptica is the agent of soft rot of potato and causes important crop damage in Europe. Synthetic 2,4-diacetylphloroglucinol (DAPG) inhibited the growth of E. carotovora subsp. atroseptica under in vitro conditions and Pseudomonas fluorescens F113, which produces DAPG, was studied for biocontrol of E. carotovora subsp. atroseptica. Wild-type F113 (or the spontaneous rifampicin-resistant mutant F113Rif) inhibited growth

Don Cronin; Yvan Monne-Loccoz; Anne Fenton; Colum Dunne; David N Dowling; Fergal O'Gara

1997-01-01

375

The chromosome map of Bacillus thuringiensis subsp. canadensis HD224 is highly similar to that of the Bacillus cereus type strain ATCC 14579  

Microsoft Academic Search

A physical map of the Bacillus thuringiensis subsp. canadensis HD224 chromosome based on AscI, NotI, and SfiI restriction sites has been established. The chromosome map of 4.3 Mb was similar to a revised map of the chromosome of the B. cereus type strain ATCC 14579, except that the B. thuringiensis subsp. canadensis HD224 chromosome lacked a NotI site and had

Cathrine Rein Carlson; Trine Johansen; Anne-Brit Kolst

1996-01-01

376

Comparison of Culture and a Novel 5 Taq Nuclease Assay for Direct Detection of Campylobacter fetus subsp. venerealis in Clinical Specimens from Cattle  

Microsoft Academic Search

A Campylobacter fetus subsp. venerealis-specific 5 Taq nuclease PCR assay using a 3 minor groove binder- DNA probe (TaqMan MGB) was developed based on a subspecies-specific fragment of unknown identity (S. Hum, K. Quinn, J. Brunner, and S. L. On, Aust. Vet. J. 75:827-831, 1997). The assay specifically detected four C. fetus subsp. venerealis strains with no observed cross-reaction with

Lyle McMillen; Geoffry Fordyce; Vivienne J. Doogan; Ala E. Lew

377

Co-occurrence patterns of trees along macro-climatic gradients and their potential influence on the present and future distribution of Fagus sylvatica L.  

USGS Publications Warehouse

Aim During recent and future climate change, shifts in large-scale species ranges are expected due to the hypothesized major role of climatic factors in regulating species distributions. The stress-gradient hypothesis suggests that biotic interactions may act as major constraints on species distributions under more favourable growing conditions, while climatic constraints may dominate under unfavourable conditions. We tested this hypothesis for one focal tree species having three major competitors using broad-scale environmental data. We evaluated the variation of species co-occurrence patterns in climate space and estimated the influence of these patterns on the distribution of the focal species for current and projected future climates.Location Europe.Methods We used ICP Forest Level 1 data as well as climatic, topographic and edaphic variables. First, correlations between the relative abundance of European beech (Fagus sylvatica) and three major competitor species (Picea abies, Pinus sylvestris and Quercus robur) were analysed in environmental space, and then projected to geographic space. Second, a sensitivity analysis was performed using generalized additive models (GAM) to evaluate where and how much the predicted F. sylvatica distribution varied under current and future climates if potential competitor species were included or excluded. We evaluated if these areas coincide with current species co-occurrence patterns.Results Correlation analyses supported the stress-gradient hypothesis: towards favourable growing conditions of F. sylvatica, its abundance was strongly linked to the abundance of its competitors, while this link weakened towards unfavourable growing conditions, with stronger correlations in the south and at low elevations than in the north and at high elevations. The sensitivity analysis showed a potential spatial segregation of species with changing climate and a pronounced shift of zones where co-occurrence patterns may play a major role.Main conclusions Our results demonstrate the importance of species co-occurrence patterns for calibrating improved species distribution models for use in projections of climate effects. The correlation approach is able to localize European areas where inclusion of biotic predictors is effective. The climate-induced spatial segregation of the major tree species could have ecological and economic consequences. ?? 2010 Blackwell Publishing Ltd.

Meier, E. S.; Edwards, Jr, T. C.; Kienast, F.; Dobbertin, M.; Zimmermann, N. E.

2011-01-01

378

The effect of carbohydrate accumulation and nitrogen deficiency on feedback regulation of photosynthesis in beech (Fagus sylvatica) under elevated CO2 concentration  

NASA Astrophysics Data System (ADS)

One of the main manifestations of global change is an increase in atmospheric CO2 concentration. Elevated concentration of CO2 has stimulating effect on plant photosynthesis and consequently also on the productivity. Long-term studies, however, show that this effect is progressively reduced due to feedback regulation of photosynthesis. The main causes of this phenomenon are considered as two factors: i) increased biomass production consumes a larger amount of nitrogen from the soil and this leads to progressive nitrogen limitation of photosynthesis, particularly at the level of the enzyme Rubisco, ii) the sink capacity is genetically limited and elevated CO2 concentration leads to increased accumulation of carbohydtrates (mainly sucrose, which is the main transport form of assimilates) in leaves. Increased concentrations of carbohydrates leads to a feedback regulation of photosynthesis by both, long-term feedback regulation of synthesis of the enzyme Rubisco, and also due to reduced capacity to produce ATP in the chloroplasts. However, mechanisms for interactive effects of nitrogen and accumulation of non-structural carbohydrates are still not well understood. Using 3-year-old Fagus sylvatica seedlings we have explored the interactive effects of nitrogen nutrition and sink capacity manipulation (sucrose feeding) on the dynamics of accumulation of non-structural carbohydrates and changes in photosynthetic parameters under ambient (385 ?mol (CO2) mol-1) and elevated (700 ?mol(CO2) mol-1) CO2 concentration. Sink manipulation by sucrose feeding led to a continuous increase of non-structural carbohydrates in leaves, which was higher in nitrogen fertilized seedlings. The accumulation of non-structural carbohydrates was also slightly stimulated by elevated CO2 concentration. Exponential decay (p <0.01) was observed in CO2 assimilation rate and stomatal conductance when the content of non-structural carbohydrates increased. However, this relationship was modified by the nitrogen content. Accumulation of non-structural carbohydrates had relatively smaller effect on actual quantum yield of photosystem II. Both, CO2 assimilation rate and the actual quantum yield of photosystem II decreased more rapidly during sink manipulation in elevated concentrations of CO2 than in ambient. Application of chlorophyll fluorescence imaging enabled us to evaluate changes in spatial distribution of feedback regulation of photosynthesis on the leaf-level. We can conclude that the accumulation of non-structural carbohydrates down-regulates photosynthesis mainly through the stomatal conductance, and this effect is further modified by nitrogen content.

Klem, K.; Urban, O.; Holub, P.; Rajsnerova, P.

2012-04-01

379

Prevalence and comparison of Streptococcus infantarius subsp. infantarius and Streptococcus gallolyticus subsp. macedonicus in raw and fermented dairy products from East and West Africa.  

PubMed

Streptococcus infantarius subsp. infantarius (Sii) and Streptococcus gallolyticus subsp. macedonicus are members of the Streptococcus bovis/Streptococcus equinus complex (SBSEC) associated with human infections. SBSEC-related endocarditis was furthermore associated with rural residency in Southern Europe. SBSEC members are increasingly isolated as predominant species from fermented dairy products in Europe, Asia and Africa. African variants of Sii displayed dairy adaptations to lactose metabolism paralleling those of Streptococcus thermophilus including genome decay. In this study, the aim was to assess the prevalence of Sii and possibly other SBSEC members in dairy products of East and West Africa in order to identify their habitat, estimate their importance in dairy fermentation processes and determine geographic areas affected by this potential health risk. Presumptive SBSEC members were isolated on semi-selective M17 and SM agar media. Subsequent genotypic identification of isolates was based on rep-PCR fingerprinting and SBSEC-specific16S rRNA gene PCR assay. Detailed identification was achieved through application of novel primers enhancing the binding stringency in partial groES/groEL gene amplification and subsequent DNA sequencing. The presence of S. thermophilus-like lacS and lacZ genes in the SBSEC isolates was determined to elucidate the prevalence of this dairy adaptation. Isolates (n = 754) were obtained from 72 raw and 95 fermented milk samples from Cte d'Ivoire and Kenya on semi-selective agar media. Colonies of Sii were not detected from raw milk despite high microbial titers of approximately 10(6)CFU/mL on M17 agar medium. However, after spontaneous milk fermentation Sii was genotypically identified in 94.1% of Kenyan samples and 60.8% of Kenyan isolates. Sii prevalence in Cte d'Ivoire displayed seasonal variations in samples from 32.3% (June) to 40.0% (Dec/Jan) and isolates from 20.5% (June) to 27.7% (Dec/Jan) present at titers of 10(6)-10(8)CFU/mL. lacS and lacZ genes were detected in all Kenyan and 25.8% (June) to 65.4% (Dec/Jan) of Ivorian Sii isolates. Regional differences in prevalence of Sii and dairy adaptations were observed, but no clear effect of dairy animal, fermentation procedure and climate was revealed. Conclusively, the high prevalence of Sii in Kenya, Cte d'Ivoire in addition to Somalia, Sudan and Mali strongly indicates a pivotal role of Sii in traditional African dairy fermentations potentially paralleling that of typical western dairy species S. thermophilus. Putative health risks associated with the consumption of high amounts of live Sii and potential different degrees of evolutionary adaptation or ecological colonization require further epidemiologic and genomic investigations, particularly in Africa. PMID:24131584

Jans, Christoph; Kaindi, Dasel Wambua Mulwa; Bck, Dsire; Njage, Patrick Murigu Kamau; Kouam-Sina, Sylvie Mireille; Bonfoh, Bassirou; Lacroix, Christophe; Meile, Leo

2013-10-15

380

Differentiation of Paenibacillus larvae subsp. larvae, the Cause of American Foulbrood of Honeybees, by Using PCR and Restriction Fragment Analysis of Genes Encoding 16S rRNA  

PubMed Central

A rapid procedure for the identification of Paenibacillus larvae subsp. larvae, the causal agent of American foulbrood (AFB) disease of honeybees (Apis mellifera L.), based on PCR and restriction fragment analysis of the 16S rRNA genes (rDNA) is described. Eighty-six bacterial strains belonging to 39 species of the genera Paenibacillus, Bacillus, Brevibacillus, and Virgibacillus were characterized. Amplified rDNA was digested with seven restriction endonucleases. The combined data from restriction analysis enabled us to distinguish 35 profiles. Cluster analysis revealed that P. larvae subsp. larvae and Paenibacillus larvae subsp. pulvifaciens formed a group with about 90% similarity; however, the P. larvae subsp. larvae restriction fragment length polymorphism pattern produced by endonuclease HaeIII was found to be unique and distinguishable among other closely related bacteria. This pattern was associated with DNA extracted directly from honeybee brood samples showing positive AFB clinical signs that yielded the restriction profile characteristic of P. larvae subsp. larvae, while no amplification product was obtained from healthy larvae. The method described here is particularly useful because of the short time required to carry it out and because it allows the differentiation of P. larvae subsp. larvae-infected larvae from all other species found in apiarian sources. PMID:12089057

Alippi, Adriana M.; Lpez, Ana Claudia; Aguilar, O. Mario

2002-01-01

381

Genome-Wide DNA Microarray Analysis of Francisella tularensis Strains Demonstrates Extensive Genetic Conservation within the Species but Identifies Regions That Are Unique to the Highly Virulent F. tularensis subsp. tularensis  

PubMed Central

Francisella tularensis is a potent pathogen and a possible bioterrorism agent. Little is known, however, to explain the molecular basis for its virulence and the distinct differences in virulence found between the four recognized subspecies, F. tularensis subsp. tularensis, F. tularensis subsp. mediasiatica, F. tularensis subsp. holarctica, and F. tularensis subsp. novicida. We developed a DNA microarray based on 1,832 clones from a shotgun library used for sequencing of the highly virulent strain F. tularensis subsp. tularensis Schu S4. This allowed a genome-wide analysis of 27 strains representing all four subspecies. Overall, the microarray analysis confirmed a limited genetic variation within the species F. tularensis, and when the strains were compared, at most 3.7% of the probes showed differential hybridization. Cluster analysis of the hybridization data revealed that the causative agents of type A and type B tularemia, i.e., F. tularensis subsp. tularensis and F. tularensis subsp. holarctica, respectively, formed distinct clusters. Despite marked differences in their virulence and geographical origin, a high degree of genomic similarity between strains of F. tularensis subsp. tularensis and F. tularensis subsp. mediasiatica was apparent. Strains from Japan clustered separately, as did strains of F. tularensis subsp. novicida. Eight regions of difference (RD) 0.6 to 11.5 kb in size, altogether comprising 21 open reading frames, were identified that distinguished strains of the moderately virulent subspecies F. tularensis subsp. holarctica and the highly virulent subspecies F. tularensis subsp. tularensis. One of these regions, RD1, allowed for the first time the development of an F. tularensis-specific PCR assay that discriminates each of the four subspecies. PMID:12843022

Broekhuijsen, Martien; Larsson, Par; Johansson, Anders; Bystrom, Mona; Eriksson, Ulla; Larsson, Eva; Prior, Richard G.; Sjostedt, Anders; Titball, Richard W.; Forsman, Mats

2003-01-01

382

Genetic uniformity of international isolates of Leifsonia xyli subsp. xyli , causal agent of ratoon stunting disease of sugarcane  

Microsoft Academic Search

An international collection of the sugarcane ratoon stunting disease pathogen, Leifsonia xyli subsp. xyli, was analysed to assess genetic diversity. DNA fingerprinting using BOX primers was performed on 105 isolates, comprising\\u000a 65 Australian isolates and an additional 40 isolates from Indonesia (n=8), Japan (n=1), USA (n=3), Brazil (n=2), Mali (n=2), Zimbabwe (n=13), South Africa (n=9) and Runion (n=2). Sixty-two of

A. J. Young; L. A. Petrasovits; B. J. Croft; M. Gillings; S. M. Brumbley

2006-01-01

383

Roquette, Eruca vesicaria subsp. sativa a good host for long-term maintenance of aphid vectors of potato viruses  

Microsoft Academic Search

Since 1971, we have used roquette,Eruca vesicaria (L.) Cav. subsp.sativa (Mill.) Thell., as a host for prolonged maintenance of colonies of the green peach aphid,Myzus persicae (Sulzer), and the potato aphid,Macrosiphum euphorbiae (Thomas). When roquette plants were kept in a growth chamber with 12 hour light and dark periods and a temperature regime\\u000a of 20C light and 15C dark, or

R. W. Goth; R. E. Webb

1980-01-01

384

Longitudinal study of interferon-gamma, serum antibody and milk antibody responses in cattle infected with Mycobacterium avium subsp. paratuberculosis  

Microsoft Academic Search

During a 2-year study period, 252 animals from dairy herds infected with Mycobacterium avium subsp. paratuberculosis, and 119 animals from non-infected herds were subjected to repeated blood and faecal sampling. Animals were retrospectively grouped by infection status as infected, exposed (culture negative animals from infected herds), or non-infected animals, and by age, 1223 months (1+ year), 2435 months (2+ years),

A. Huda; G. Jungersen; P. Lind

2004-01-01

385

Antimicrobial Effects of a Hexapetide KCM21 against Pseudomonas syringae pv. tomato DC3000 and Clavibacter michiganensis subsp. michiganensis  

PubMed Central

Antimicrobial peptides (AMPs) are small but effective cationic peptides with variable length. In previous study, four hexapeptides were identified that showed antimicrobial activities against various phytopathogenic bacteria. KCM21, the most effective antimicrobial peptide, was selected for further analysis to understand its modes of action by monitoring inhibitory effects of various cations, time-dependent antimicrobial kinetics, and observing cell disruption by electron microscopy. The effects of KCM21 on Gram-negative strain, Pseudomonas syringae pv. tomato DC3000 and Gram-positive strain, Clavibacter michiganensis subsp. michiganensis were compared. Treatment with divalent cations such as Ca2+ and Mg2+ inhibited the bactericidal activities of KCM21 significantly against P. syringae pv. tomato DC3000. The bactericidal kinetic study showed that KCM21 killed both bacteria rapidly and the process was faster against C. michiganensis subsp. michiganensis. The electron microscopic analysis revealed that KCM21 induced the formation of micelles and blebs on the surface of P. syringae pv. tomato DC3000 cells, while it caused cell rupture against C. michiganensis subsp. michiganensis cells. The outer membrane alteration and higher sensitivity to Ca2+ suggest that KCM21 interact with the outer membrane of P. syringae pv. tomato DC3000 cells during the process of killing, but not with C. michiganensis subsp. michiganensis cells that lack outer membrane. Considering that both strains had similar sensitivity to KCM21 in LB medium, outer membrane could not be the main target of KCM21, instead common compartments such as cytoplasmic membrane or internal macromolecules might be a possible target(s) of KCM21.

Choi, Jeahyuk; Baek, Kwang-Hyun; Moon, Eunpyo

2014-01-01

386

Allozyme Diversity and Geographic Variation among Populations of the Locally Endangered Taxon Carex magellanica subsp. irrigua (Cyperaceae)  

Microsoft Academic Search

Carex magellanica subsp. irrigua is a wet habitat taxon that is extinct or declining in the Baltic States and Central Europe, but still quite common in northern\\u000a areas, in Fennoscandia and Alaska. We investigated the extent of genetic variation within and among populations and geographic\\u000a regions of this subspecies. Isozyme electrophoresis in polyacrylamide gels was applied to characterize genetic diversity

Thea Kull; Tatjana Oja

2010-01-01

387

Activation of flavonoid biosynthesis in roots of Vicia sativa subsp. nigra plants by inoculation with Rhizobium leguminosarum biovar viciae  

Microsoft Academic Search

Infective (nodulating) Rhizobium leguminosarum biovar viciae (R.l. viciae) bacteria release Nod factors which stimulate the release of nodulation gene-inducing flavanones and chalcones from roots of the host plant Vicia sativa subsp. nigra (K. Recourt et al., Plant Mol Biol 16: 841852; H.P. Spaink et al., Nature 354: 125130). The hypothesis that this release results from increased synthesis of flavonoids was

Kees Recourt; Arjen J. van Tunen; Leon A. Mur; Anton A. N. Brussel; Ben J. J. Lugtenberg; Jan W. Kijne

1992-01-01

388

Survival of plains cottonwood ( Populus deltoides subsp. Monilifera ) and saltcedar ( Tamarix ramosissima ) seedlings in response to flooding  

Microsoft Academic Search

We examined the response of first year saltcedar (Tamarix ramosissima) and plains cottonwood (Populus deltoides subsp.monilifera) seedlings to flooding in fall (25 days) and spring (28 days) using potgrown plants (1218 individuals\\/26.5-liter pot). Seedlings\\u000a were initially counted in all pots prior to fall treatment. Survival was calculated as the proportion of seedlings in cach\\u000a pot still alive following spring treatment.

Douglas N. Gladwin; James E. Roelle

1998-01-01

389

Physiological Aspects of Cadmium and Nickel Toxicity in the Lichens Peltigera rufescens and Cladina arbuscula Subsp. mitis  

Microsoft Academic Search

This study was undertaken with the aim of investigating the effect of Cd2+ and Ni2+ containing solutions on selected physiological parameters (metal uptake, chlorophyll a fluorescence, assimilation pigment composition, thiobarbituric acid-reactive substance production, and ergosterol content)\\u000a in the lichens Peltigera rufescens and Cladina arbuscula subsp. mitis growing on historic copper mine-spoil heaps at ?ubietov-Podlipa, Slovakia. Physiological measurements did not confirm

Martin Ba?kor; Jozef Kov?ik; Juraj Piovr; Tommaso Pisani; Stefano Loppi

2010-01-01

390

Physiological comparison of copper toxicity in the lichens Peltigera rufescens (Weis) Humb. and Cladina arbuscula subsp. mitis (Sandst.) Ruoss  

Microsoft Academic Search

Peltigera rufescens (Weis) Humb. with a prokaryotic photobiont Nostoc sp. and Cladina arbuscula subsp. mitis (Sandst.) Ruoss with a eukaryotic photobiont Trebouxia sp. were studied to determine the copper sensitivity of lichens with different algal symbionts. Samples growing on historic\\u000a copper mine-spoil heaps at ?ubietovPodlipa, Slovakia were assessed for physiological parameters, including total and intracellular\\u000a uptake of copper, assimilation pigmentation,

Martin Ba?kor; Jozef Kov?ik; Alexander Dzubaj; Miriam Ba?korov

2009-01-01

391

Pollination in small islands by occasional visitors: the case of Daucus carota subsp. commutatus (Apiaceae) in the Columbretes archipelago, Spain  

Microsoft Academic Search

This study investigates the pollination ecology and related floral traits of the species Daucus carota subsp. commutatus in the isolated archipelago of Columbretes, E. Spain, where bees are absent. Two populations were studied: a small population\\u000a found on a relatively large island (Grossa) inhabited nowadays by three people; and a larger population on a smaller uninhabited\\u000a island (Foradada). The plant,

Celeste Prez-Ban; Theodora Petanidou

2007-01-01

392

Evaluation of a Rapid Fecal PCR Test for Detection of Mycobacterium avium subsp. paratuberculosis in Dairy Cattle  

Microsoft Academic Search

A high-throughput TaqMan PCR assay for detection of bovine paratuberculosis was evaluated by using fecal samples from 1,808 dairy cattle in seven naturally infected herds and 347 dairy cattle in seven herds considered free of paratuberculosis. Fecal, blood, and milk samples were submitted to laboratories where the PCR-based assay, three different fecal culture procedures for Mycobacterium avium subsp. paratuberculosis (centrifugation,

Scott J. Wells; Michael T. Collins; Kay S. Faaberg; Carrie Wees; Saraya Tavornpanich; Kristine R. Petrini; James E. Collins; Natalia Cernicchiaro; Robert H. Whitlock

2006-01-01

393

Ecological conditions and the distribution of alpine juniper ( Juniperus communis subsp. alpina ) in the Hrub Jesenk Mts  

Microsoft Academic Search

In the Hrub Jesenk Mts of the Czech Republic, research was carried out from 20012005 aimed at completing an up-to-date\\u000a census of alpine juniper [Juniperus communis subsp. alpine (Smith) ?elakovsk] and an evaluation of the overall health status of the populations, and at investigating the impacts of\\u000a the main environmental factors on the viability of this species. 13 sites were

Miroslav Zeidler; Marek Bana; Michaela enat

2009-01-01

394

Dissemination of Salmonella enterica subsp. enterica Serovar Typhimurium var. Copenhagen Clonal Types through a Contract Heifer-Raising Operation  

Microsoft Academic Search

Salmonella enterica subsp. enterica serovar Typhimurium var. Copenhagen isolates from a heifer-raising operation and from 11 dairy herds that had their calves contracted to the heifer-raising operation were examined for their phenotypic and genotypic characteristics. Results of the study showed that the heifer-raising operation could serve as a clearinghouse for Salmonella serovar Typhimurium var. Copenhagen and perhaps other Salmonella serotypes.

Narasimha V. Hegde; Michelle L. Cook; David R. Wolfgang; Brenda C. Love; Carol C. Maddox; Bhushan M. Jayarao

2005-01-01

395

The wildlife hosts of Mycobacterium avium subsp. paratuberculosis in the Czech Republic during the years 2002-2007  

Microsoft Academic Search

The objective of this study was to determine the wildlife hosts of Mycobacterium avium subsp. paratuberculosis (MAP) in the Czech Republic. A total of 8 796 wildlife animals were examined by culture of faecal or tissue samples during the years 2002-2007. MAP was isolated from 12 (0.5%) out of 2 296 red deer ( Cervus elaphus), two (0.2%) out of

M. Kopecna; I. Trcka; J. Lamka; M. Moravkova; P. Koubek; M. Heroldova; V. Mrlik; A. Kralova; I. Pavlik

396

Sequence Diversity of Treponema pallidum subsp. pallidum tprK in Human Syphilis Lesions and Rabbit-Propagated Isolates  

Microsoft Academic Search

The tprK gene of Treponema pallidum subsp. pallidum, the causative agent of venereal syphilis, belongs to a 12-member gene family and encodes a protein with a predicted cleavable signal sequence and predicted transmembrane domains. Except for the Nichols type strain, all rabbit-propagated isolates of T. pallidum examined thus far are comprised of mixed populations of organisms with heterogeneous tprK sequences.

Rebecca E. LaFond; Arturo Centurion-Lara; Charmie Godornes; Anne M. Rompalo; Wesley C. Van Voorhis; Sheila A. Lukehart

2003-01-01

397

Complete genome sequence of Polynucleobacter necessarius subsp. asymbioticus type strain (QLW-P1DMWA-1T)  

SciTech Connect

Polynucleobacter necessarius subsp. asymbioticus Hahn et al. 2009 is one of currently two subspecies of P. necessarius. While P. necessarius subsp. asymbioticus is a free-living bacterium, the closely related second subspecies, P. necessarius subsp. necessarius is an obligate endosymbiont living in the cytoplasm of freshwater ciliates of the genus Euplotes aediculatus. The two P. necessarius subspecies were the closest thus far reported phylogenetic neighbors that differ in their lifestyle as obligately free-living vs. obligate endosymbiontic, and they are the only members of the genus Polynucleobacter with completely sequenced genomes. The genome-sequenced strain represents a group of closely related strains not distinguishable by 16S rRNA, 16S-23S ITS or glnA sequences, which is persistent in the home habitat of the strain and frequently contributes > 10% of total bacterial numbers in water samples of the habitat. The 2,159,490 bp long chromosome with a total of 2,088 protein-coding and 48 RNA genes was sequenced as part of the DOE Joint Genome Institute Community Sequencing Program 2006.

Meincke, Linda [Los Alamos National Laboratory (LANL); Copeland, A [U.S. Department of Energy, Joint Genome Institute; Lapidus, Alla L. [U.S. Department of Energy, Joint Genome Institute; Lucas, Susan [U.S. Department of Energy, Joint Genome Institute; Berry, Kerrie W. [United States Department of Energy Joint Genome Institute; Glavina Del Rio, Tijana [U.S. Department of Energy, Joint Genome Institute; Hammon, Nancy [U.S. Department of Energy, Joint Genome Institute; Dalin, Eileen [U.S. Department of Energy, Joint Genome Institute; Tice, Hope [U.S. Department of Energy, Joint Genome Institute; Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Richardson, P M [U.S. Department of Energy, Joint Genome Institute; Bruce, David [Los Alamos National Laboratory (LANL); Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Han, Cliff [Los Alamos National Laboratory (LANL); Tapia, Roxanne [Los Alamos National Laboratory (LANL); Detter, J. Chris [U.S. Department of Energy, Joint Genome Institute; Schmutz, Jeremy [Stanford University; Brettin, Thomas S [ORNL; Larimer, Frank W [ORNL; Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute; Ivanova, N [U.S. Department of Energy, Joint Genome Institute; Goker, Markus [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany; Woyke, Tanja [U.S. Department of Energy, Joint Genome Institute; Wu, Qinglong L. [Austrian Academy of Sciences, Institute for Limnology, Mondsee, Austria; Pockl, Matthias [Austrian Academy of Sciences, Institute for Limnology, Mondsee, Austria; Hahn, Martin W. [Austrian Academy of Sciences, Institute for Limnology, Mondsee, Austria; Klenk, Hans-Peter [DSMZ - German Collection of Microorganisms and Cell Cultures GmbH, Braunschweig, Germany

2012-01-01

398

Exposure of Bifidobacterium longum subsp. infantis to Milk Oligosaccharides Increases Adhesion to Epithelial Cells and Induces a Substantial Transcriptional Response  

PubMed Central

In this study, we tested the hypothesis that milk oligosaccharides may contribute not only to selective growth of bifidobacteria, but also to their specific adhesive ability. Human milk oligosaccharides (3?sialyllactose and 6?sialyllactose) and a commercial prebiotic (Beneo Orafti P95; oligofructose) were assayed for their ability to promote adhesion of Bifidobacterium longum subsp. infantis ATCC 15697 to HT-29 and Caco-2 human intestinal cells. Treatment with the commercial prebiotic or 3?sialyllactose did not enhance adhesion. However, treatment with 6?sialyllactose resulted in increased adhesion (4.7 fold), while treatment with a mixture of 3?- and 6?-sialyllactose substantially increased adhesion (9.8 fold) to HT-29 intestinal cells. Microarray analyses were subsequently employed to investigate the transcriptional response of B. longum subsp. infantis to the different oligosaccharide treatments. This data correlated strongly with the observed changes in adhesion to HT-29 cells. The combination of 3?- and 6?-sialyllactose resulted in the greatest response at the genetic level (both in diversity and magnitude) followed by 6?sialyllactose, and 3?sialyllactose alone. The microarray data was further validated by means of real-time PCR. The current findings suggest that the increased adherence phenotype of Bifidobacterium longum subsp. infantis resulting from exposure to milk oligosaccharides is multi-faceted, involving transcription factors, chaperone proteins, adhesion-related proteins, and a glycoside hydrolase. This study gives additional insight into the role of milk oligosaccharides within the human intestine and the molecular mechanisms underpinning host-microbe interactions. PMID:23805302

Kavanaugh, Devon W.; OCallaghan, John; Butt, Ludovica F.; Slattery, Helen; Lane, Jonathan; Clyne, Marguerite; Kane, Marian; Joshi, Lokesh; Hickey, Rita M.

2013-01-01

399

Characterization of genes required for the pathogenicity of Pectobacterium carotovorum subsp. carotovorum Pcc21 in Chinese cabbage.  

PubMed

Pectobacterium carotovorum subsp. carotovorum is a well-known plant pathogen that causes severe soft rot disease in various crops, resulting in considerable economic loss. To identify pathogenicity-related factors, Chinese cabbage was inoculated with 5314 transposon mutants of P. carotovorum subsp. carotovorum Pcc21 derived using Tn5 transposon mutagenesis. A total of 35 reduced-virulence or avirulent mutants were isolated, and 14 loci were identified. The 14 loci could be functionally grouped into nutrient utilization (pyrD, purH, purD, leuA and serB), production of plant cell-wall-degrading enzymes (PCWDEs) (expI, expR and PCC21_023220), motility (flgA, fliA and flhB), biofilm formation (expI, expR and qseC), susceptibility to antibacterial plant chemicals (tolC) and unknown function (ECA2640). Among the 14 genes identified, qseC, tolC and PCC21_023220 are novel pathogenicity factors of P. carotovorum subsp. carotovorum involved in biofilm formation, phytochemical resistance and PCWDE production, respectively. PMID:23676432

Lee, Dong Hwan; Lim, Jeong-A; Lee, Juneok; Roh, Eunjung; Jung, Kyusuk; Choi, Minseon; Oh, Changsik; Ryu, Sangryeol; Yun, Jongchul; Heu, Sunggi

2013-07-01

400

Characterization of genes required for the pathogenicity of Pectobacterium carotovorum subsp. carotovorum Pcc21 in Chinese cabbage  

PubMed Central

Pectobacterium carotovorum subsp. carotovorum is a well-known plant pathogen that causes severe soft rot disease in various crops, resulting in considerable economic loss. To identify pathogenicity-related factors, Chinese cabbage was inoculated with 5314 transposon mutants of P. carotovorum subsp. carotovorum Pcc21 derived using Tn5 transposon mutagenesis. A total of 35 reduced-virulence or avirulent mutants were isolated, and 14 loci were identified. The 14 loci could be functionally grouped into nutrient utilization (pyrD, purH, purD, leuA and serB), production of plant cell-wall-degrading enzymes (PCWDEs) (expI, expR and PCC21_023220), motility (flgA, fliA and flhB), biofilm formation (expI, expR and qseC), susceptibility to antibacterial plant chemicals (tolC) and unknown function (ECA2640). Among the 14 genes identified, qseC, tolC and PCC21_023220 are novel pathogenicity factors of P. carotovorum subsp. carotovorum involved in biofilm formation, phytochemical resistance and PCWDE production, respectively. PMID:23676432

Lee, Dong Hwan; Lim, Jeong-A; Lee, Juneok; Roh, Eunjung; Jung, Kyusuk; Choi, Minseon; Oh, Changsik; Ryu, Sangryeol; Yun, Jongchul

2013-01-01

401

Improved trehalose production from biodiesel waste using parent and osmotically sensitive mutant of Propionibacterium freudenreichii subsp. shermanii under aerobic conditions.  

PubMed

Trehalose is an important nutraceutical of wide commercial interest in the food processing industry. Recently, crude glycerol was reported to be suitable for the production of trehalose using a food microbe, Propionibacterium freudenreichii subsp. shermanii, under static flask conditions. Similarly, enhanced trehalose yield was reported in an osmotically sensitive mutant of the same strain under anaerobic conditions. In the present study, an effort was made to achieve higher production of trehalose, propionic acid, and lactic acid using the parent and an osmotically sensitive mutant of P. freudenreichii subsp. shermanii under aeration conditions. Under aeration conditions (200 rpm in shake flasks and 30 % air saturation in a batch reactor), biomass was increased and approximately 98 % of crude glycerol was consumed. In the parent strain, a trehalose titre of 361 mg/l was achieved, whereas in the mutant strain a trehalose titre of 1.3 g/l was produced in shake flask conditions (200 rpm). In the mutant strain, propionic and lactic acid yields of 0.53 and 0.21 g/g of substrate were also achieved with crude glycerol. Similarly, in controlled batch reactor culturing conditions a final trehalose titre of approximately 1.56 g/l was achieved with the mutant strain using crude glycerol as the substrate. Enhanced production of trehalose using P. freudenreichii subsp. shermanii from waste under aeration conditions is reported here. Higher production of trehalose was not due to a higher yield of trehalose but to a higher final biomass concentration. PMID:22526328

Ruhal, Rohit; Choudhury, Bijan

2012-08-01

402

Specific Discrimination of Three Pathogenic Salmonella enterica subsp. enterica Serotypes by carB-Based Oligonucleotide Microarray  

PubMed Central

It is important to rapidly and selectively detect and analyze pathogenic Salmonella enterica subsp. enterica in contaminated food to reduce the morbidity and mortality of Salmonella infection and to guarantee food safety. In the present work, we developed an oligonucleotide microarray containing duplicate specific capture probes based on the carB gene, which encodes the carbamoyl phosphate synthetase large subunit, as a competent biomarker evaluated by genetic analysis to selectively and efficiently detect and discriminate three S. enterica subsp. enterica serotypes: Choleraesuis, Enteritidis, and Typhimurium. Using the developed microarray system, three serotype targets were successfully analyzed in a range as low as 1.6 to 3.1 nM and were specifically discriminated from each other without nonspecific signals. In addition, the constructed microarray did not have cross-reactivity with other common pathogenic bacteria and even enabled the clear discrimination of the target Salmonella serotype from a bacterial mixture. Therefore, these results demonstrated that our novel carB-based oligonucleotide microarray can be used as an effective and specific detection system for S. enterica subsp. enterica serotypes. PMID:24185846

Shin, Hwa Hui; Hwang, Byeong Hee; Seo, Jeong Hyun

2014-01-01

403

The Genome Sequence of the Tomato-Pathogenic Actinomycete Clavibacter michiganensis subsp. michiganensis NCPPB382 Reveals a Large Island Involved in Pathogenicity?  

PubMed Central

Clavibacter michiganensis subsp. michiganensis is a plant-pathogenic actinomycete that causes bacterial wilt and canker of tomato. The nucleotide sequence of the genome of strain NCPPB382 was determined. The chromosome is circular, consists of 3.298 Mb, and has a high G+C content (72.6%). Annotation revealed 3,080 putative protein-encoding sequences; only 26 pseudogenes were detected. Two rrn operons, 45 tRNAs, and three small stable RNA genes were found. The two circular plasmids, pCM1 (27.4 kbp) and pCM2 (70.0 kbp), which carry pathogenicity genes and thus are essential for virulence, have lower G+C contents (66.5 and 67.6%, respectively). In contrast to the genome of the closely related organism Clavibacter michiganensis subsp. sepedonicus, the genome of C. michiganensis subsp. michiganensis lacks complete insertion elements and transposons. The 129-kb chp/tomA region with a low G+C content near the chromosomal origin of replication was shown to be necessary for pathogenicity. This region contains numerous genes encoding proteins involved in uptake and metabolism of sugars and several serine proteases. There is evidence that single genes located in this region, especially genes encoding serine proteases, are required for efficient colonization of the host. Although C. michiganensis subsp. michiganensis grows mainly in the xylem of tomato plants, no evidence for pronounced genome reduction was found. C. michiganensis subsp. michiganensis seems to have as many transporters and regulators as typical soil-inhabiting bacteria. However, the apparent lack of a sulfate reduction pathway, which makes C. michiganensis subsp. michiganensis dependent on reduced sulfur compounds for growth, is probably the reason for the poor survival of C. michiganensis subsp. michiganensis in soil. PMID:18192381

Gartemann, Karl-Heinz; Abt, Birte; Bekel, Thomas; Burger, Annette; Engemann, Jutta; Flugel, Monika; Gaigalat, Lars; Goesmann, Alexander; Grafen, Ines; Kalinowski, Jorn; Kaup, Olaf; Kirchner, Oliver; Krause, Lutz; Linke, Burkhard; McHardy, Alice; Meyer, Folker; Pohle, Sandra; Ruckert, Christian; Schneiker, Susanne; Zellermann, Eva-Maria; Puhler, Alfred; Eichenlaub, Rudolf; Kaiser, Olaf; Bartels, Daniela

2008-01-01

404

A siderophore biosynthesis gene cluster from the fish pathogen Photobacterium damselae subsp. piscicida is structurally and functionally related to the Yersinia high-pathogenicity island.  

PubMed

Photobacterium damselae subsp. piscicida, the causative agent of fish pasteurellosis, produces a siderophore which is distinct from that produced by P. damselae subsp. damselae. Using suppression subtractive hybridization, a subsp. piscicida-specific DNA region of 35 kb was identified in strain DI21, and 11 genes were defined: dahP, araC1, araC2, frpA, irp8, irp2, irp1, irp3, irp4, irp9 and irp5. The sequence of the predicted proteins encoded by these genes showed significant similarity with the proteins responsible for the synthesis and transport of the siderophore yersiniabactin, encoded within the Yersinia high-pathogenicity island (HPI). Southern hybridization demonstrated that this gene cluster is exclusive to some European subsp. piscicida isolates. Database searches revealed that a similar gene cluster is present in Photobacterium profundum SS9 and Vibrio cholerae RC385. An irp1 gene (encoding a putative non-ribosomal peptide synthetase) insertional mutant (CS31) was impaired for growth under iron-limiting conditions and unable to produce siderophores, and showed an approximately 100-fold decrease in degree of virulence for fish. The subsp. piscicida DI21 strain, but not CS31, promoted the growth of a Yersinia enterocolitica irp1 mutant. Furthermore, a yersiniabactin-producing Y. enterocolitica strain as well as purified yersiniabactin were able to cross-feed strains DI21 and CS31, suggesting that the subsp. piscicida siderophore might be functionally and structurally related to yersiniabactin. The differential occurrence among P. damselae strains, and the low sequence similarity to siderophore synthesis genes described in other members of the Vibrionaceae, suggest that this genetic system might have been acquired by horizontal transfer in P. damselae subsp. piscicida, and might have a common evolutionary origin with the Yersinia HPI. PMID:17074903

Osorio, Carlos R; Juiz-Ro, Sandra; Lemos, Manuel L

2006-11-01

405

Inhibition of bacteriochlorophyll synthesis in Rhodobacter sphaeroides subsp. denitrificans grown in light under denitrifying conditions.  

PubMed Central

The inclusion of nitrate or nitrite in cultures of Rhodobacter spaeroides subsp. denitrificans grown heterotrophically in light depressed the formation of bacteriochlorophyll a. The pigment biosynthesis was inhibited at the stage of the reduction of chlorophyllide (chlorin) to bacteriochlorophyllide (tetrahydroporphyrin) since 3-hydroxyethylchlorophyllide a accumulated in the culture medium. The addition of exogenous 5-aminolevulinic acid to these cultures resulted in a complete restoration of bacteriochlorophyll synthesis accompanied by the accumulation of 3-vinylbacteriopheophorbide. This indicates that under these conditions bacteriochlorophyll was formed via an alternative route, in which the reduction of chlorins to tetrahydroporphyrins precedes modifications of the C-3 side chain. The multiple forms of 5-aminolevulinic acid synthase were purified from cells grown with and without nitrate. Antibodies against these proteins were raised in rabbits and used in enzyme-linked immunosorbent assays for various forms of 5-aminolevulinic acid synthase. In denitrifying cells, the amount and activity of fraction I of the enzyme was reduced by approximately 40 and 30%, respectively. Partly active enzymes from both types of cells were activated by cystine trisulfide. Images PMID:3654581

Michalski, W P; Nicholas, D J

1987-01-01

406

High-level Relatedness among Mycobacterium abscessus subsp. massiliense Strains from Widely Separated Outbreaks  

PubMed Central

Three recently sequenced strains isolated from patients during an outbreak of Mycobacterium abscessus subsp. massiliense infections at a cystic fibrosis center in the United States were compared with 6 strains from an outbreak at a cystic fibrosis center in the United Kingdom and worldwide strains. Strains from the 2 cystic fibrosis outbreaks showed high-level relatedness with each other and major-level relatedness with strains that caused soft tissue infections during an epidemic in Brazil. We identified unique single-nucleotide polymorphisms in cystic fibrosis and soft tissue outbreak strains, separate single-nucleotide polymorphisms only in cystic fibrosis outbreak strains, and unique genomic traits for each subset of isolates. Our findings highlight the necessity of identifying M. abscessus to the subspecies level and screening all cystic fibrosis isolates for relatedness to these outbreak strains. We propose 2 diagnostic strategies that use partial sequencing of rpoB and secA1 genes and a multilocus sequence typing protocol. PMID:24565502

Tettelin, Herve; Davidson, Rebecca M.; Agrawal, Sonia; Aitken, Moira L.; Shallom, Shamira; Hasan, Nabeeh A.; Strong, Michael; Nogueira de Moura, Vinicius Calado; De Groote, Mary Ann; Duarte, Rafael S.; Hine, Erin; Parankush, Sushma; Su, Qi; Daugherty, Sean C.; Fraser, Claire M.; Brown-Elliott, Barbara A.; Wallace, Richard J.; Holland, Steven M.; Sampaio, Elizabeth P.; Olivier, Kenneth N.; Jackson, Mary

2014-01-01

407

Mycobacterium avium subsp. paratuberculosis in an Italian Cohort of Type 1 Diabetes Pediatric Patients  

PubMed Central

Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne's disease in ruminants. Recent studies have linked MAP to type 1 diabetes (T1D) in the Sardinian population. The aim of this study was to investigate the prevalence of MAP infection in a T1D cohort from continental Italy compared with healthy control subjects. 247 T1D subjects and 110 healthy controls were tested for the presence of MAP. MAP DNA was detected using IS900-specific polymerase chain reaction (PCR). The presence of antibodies towards a MAP antigen, heparin binding hemoagglutinin (HBHA), was detected by ELISA. We demonstrated a higher MAP DNA prevalence in plasma samples from T1D patients and a stronger immune response towards MAP HBHA, compared with healthy control subjects. Moreover, in the recent onset patients, we observed an association between anti-MAP antibodies and HLA DQ2 (DQA1 0201/DQB1 0202). These findings taken together support the hypothesis of MAP as an environmental risk factor for the development of T1D in genetically predisposed subjects, probably involving a mechanism of molecular mimicry between MAP antigens and pancreatic islet ?-cells. PMID:22844325

Manca Bitti, Maria Luisa; Masala, Speranza; Capasso, Francesca; Rapini, Novella; Piccinini, Simona; Angelini, Federica; Pierantozzi, Andrea; Lidano, Roberta; Pietrosanti, Silvia; Paccagnini, Daniela; Sechi, Leonardo A.

2012-01-01

408

Phenolic Glycosides with antiproteasomal activity from Centaurea urvillei DC. subsp. urvillei.  

PubMed

A new flavanone glycoside, naringenin-7-O-?-D-glucuronopyranoside, and a new flavonol glycoside, 6-hydroxykaempferol-7-O-?-D-glucuronopyranoside were isolated together with 12 known compounds, 5 flavone glycoside; hispidulin-7-O-?-D-glucuronopyranoside, apigenin-7-O-?-D-methylglucuronopyranoside, hispidulin-7-O-?-D-methylglucuronopyranoside, hispidulin-7-O-?-D-glucopyranoside, apigenin-7-O-?-D-glucopyranoside, a flavonol; kaempferol, two flavone; apigenin, and luteolin, a flavanone glycoside; eriodictyol-7-O-?-D-glucuronopyranoside, and three phenol glycoside; arbutin, salidroside, and 3,5-dihydroxyphenethyl alcohol-3-O-?-D-glucopyranoside from Centaurea urvillei subsp. urvillei. The structure elucidation of the new compounds was achieved by a combination of one- ((1)H and (13)C) and two-dimensional NMR techniques (G-COSY, G-HMQC, and G-HMBC) and LC-ESI-MS. The isolated compounds were tested for their antiproteasomal activity. The results indicated that kaempferol, a well known and widely distributed flavonoid in the plant kingdom, was the most active antiproteasomal agent, followed by apigenin, eriodictyol-7-O-?-D-glucuronopyranoside, 3,5-dihydroxyphenethyl alcohol-3-O-?-D-glucopyranoside, and salidroside, respectively. PMID:20937505

Glcemal, Derya; Alanku?-al??kan, Ozgen; Karaalp, Canan; Ors, Ahmet Uygar; Ballar, Petek; Bedir, Erdal

2010-11-22

409

Identification of heme uptake genes in the fish pathogen Aeromonas salmonicida subsp. salmonicida.  

PubMed

Aeromonas salmonicida subsp. salmonicida, the causative agent of furunculosis in fish, can use heme as the sole iron source. We applied the Fur Titration Assay to isolate a cluster including six genes hutAZXBCD that showed similarity to heme uptake genes of other Gram-negative bacteria, and three genes orf123 of unknown function. The spatial organization of these nine genes, arranged in five transcriptional units, was similar to that of a homologous cluster in A. hydrophila. When a TonB system was provided, this cluster allowed Escherichia coli 101ESD (an ent mutant, unable to synthesize enterobactin) to utilize hemin and hemoglobin as iron sources. Mutation of hutB, a gene that encodes a predicted periplasmic hemin-binding protein, caused a drastic defect in the ability of A. salmonicida to grow with hemin as unique source of iron. Interestingly, a mutant for hutA gene (encoding the outer membrane hemin receptor) showed initially a reduced ability to grow with hemin as sole iron source, but after 24 h it achieved growth levels similar to parental strain. Thus mutation of hutA could not abolish the growth with hemin as iron source, suggesting that redundant outer membrane heme transport functions might be encoded in the A. salmonicida genome. PMID:18535817

Najimi, Mohsen; Lemos, Manuel L; Osorio, Carlos R

2008-10-01

410

Biochemical and thermal stabilization parameters of polygalacturonase from Erwinia carotovora subsp. carotovora BR1.  

PubMed

With emphasis on thermal behavior in presence of different pH conditions and salts, the kinetic and thermodynamic parameters of purified polygalacturonase (PG) of E. carotovora subsp. carotovora (Ecc) BR1 were studied since characterization of an enzyme is significant in the context of burgeoning biotechnological applications. Thermodynamic parameters for polygalacturonic acid hydrolysis by purified PG were, deltaH* = 7.98 kJ/mol, deltaG* = 68.86 kJ/mol, deltaS*= -194.48 J/mol/K, deltaG(E-S) = -1.04 kJ/mol and deltaG(E-T) = -8.96 kJ/mol. Its turnover number (k(cat)) was 21/sec. Purified PG was stable in 20-50 degrees C temperature range and was deactivated at 60 degrees C and 70 degrees C. Thermodynamic parameters (deltaH*, deltaG*, deltaS*) for irreversible inactivation of PG at different temperatures (30-60 degrees C) were determined, where effectiveness of various salts and different pH (4-8) individually for thermal stability of PG were characterized. The efficacy of various salts for thermal stability of PG was in the following order: MgCl? >BaCl? >KCl >CaCl? >NaCl. Present work projects biochemical, thermodynamics of substrate hydrolysis as well as thermal stabilization parameters of PG from Ecc. PMID:20668400

Maisuria, Vimal B; Patel, Vilas A; Nerurkar, Anuradha S

2010-07-01

411

Dendroclimatic potential of plains cottonwood (Populus deltoides subsp. monilifera) from the Northern Great Plains, USA  

USGS Publications Warehouse

A new 368-year tree-ring chronology (A.D. 16432010) has been developed in western North Dakota using plains cottonwood (Populus deltoides subsp. monilifera) growing on the relatively undisturbed floodplain of the Little Missouri River in the North Unit of Theodore Roosevelt National Park. We document many slow-growing living trees between 150370 years old that contradict the common understanding that cottonwoods grow fast and die young. In this northern location, cottonwood produces distinct annual rings with dramatic interannual variability that strongly crossdate. The detrended tree-ring chronology is significantly positively correlated with local growing season precipitation and soil moisture conditions (r ?=? 0.69). This time series shows periods of prolonged low radial tree growth during the known droughts of the instrumental record (e.g. 19311939 and 19801981) and also during prehistory (e.g. 18161823 and 18561865) when other paleoclimate studies have documented droughts in this region. Tree rings of cottonwood will be a useful tool to help reconstruct climate, streamflow, and the floodplain history of the Little Missouri River and other northern river systems.

Edmonson, Jesse; Friedman, Jonathan; Meko, David; Touchan, Ramzi; Scott, Julian; Edmonson, Alan

2014-01-01

412

Anaerobic Nitrate Respiration by Erwinia carotovora subsp. atroseptica during Potato Tuber Invasion  

PubMed Central

The in planta induction of anaerobic nitrate respiration by Erwinia carotovora subsp. atroseptica in relation to the in situ oxygen status in soft rotting potato tubers has been investigated. In vitro experiments have shown that nitrate was required for the induction of respiratory nitrate reductase activity in E. carotovora. In addition, oxygen was found to repress this activity. Expression of respiratory nitrate reductase was found in E. carotovora cells extracted from soft rotting potato tuber tissue. However, the rate of nitrite production in these cells was approximately 70-fold lower than the rate recorded in fully induced anaerobic cultures. Oxygen measurements in soft rotting potato tubers indicated that the invading bacteria encounter the lowest oxygen concentration at the interphase between healthy and macerated tissue. Consequently, growth of bacteria present in this specific zone will be stimulated by nitrate which is present in sufficient amounts in tuber tissue. A high nitrate content of the tuber will most likely facilitate the proliferation of E. carotovora in the tuber tissue. PMID:16349082

Smid, Eddy J.; Jansen, Antonius H. J.; Tuijn, Cees J.

1993-01-01

413

Mycobacterium avium subsp. avium found in raptors exposed to infected domestic fowl.  

PubMed

We report a case of a falcon breeding facility, where raptors (both diurnal and nocturnal) were raised in contact with domestic fowl (Gallus gallus f. domesticus) infected by Mycobacterium avium subsp. avium. Fecal and environmental samples from 20 raptors and four common ravens (Corvus corax) were collected. Mycobacterium a. avium DNA was detected in feces of four raptors (bald eagle [Haliaeetus leucocephalus], eagle owl [Bubo bubo], barn owl [Tyto alba], and little owl [Athene noctua]) using triplex quantitative real-time PCR. As both the flock of domestic fowl and one of the infected raptors had the same origin (zoological collection), they might have had a common source of colonization/infection. However, the detection of M. a. avium in feces of three other raptors may point at transmission of the agent between the birds in the facility. Contact of raptors with domestic fowl infected by M. a. avium may pose a risk for transmission of the infection for them; however, raptors from the falcon breeding facility seemed to be relatively resistant to the infection. PMID:24283140

Kriz, Petr; Kaevska, Marija; Bartejsova, Iva; Pavlik, Ivo

2013-09-01

414

From mouth to macrophage: mechanisms of innate immune subversion by Mycobacterium avium subsp. paratuberculosis  

PubMed Central

Johnes disease (JD) is a chronic enteric infection of cattle caused by Mycobacterium avium subsp. paratuberculosis (MAP). The high economic cost and potential zoonotic threat of JD have driven efforts to develop tools and approaches to effectively manage this disease within livestock herds. Efforts to control JD through traditional animal management practices are complicated by MAPs ability to cause long-term environmental contamination as well as difficulties associated with diagnosis of JD in the pre-clinical stages. As such, there is particular emphasis on the development of an effective vaccine. This is a daunting challenge, in large part due to MAPs ability to subvert protective host immune responses. Accordingly, there is a priority to understand MAPs interaction with the bovine host: this may inform rational targets and approaches for therapeutic intervention. Here we review the early host defenses encountered by MAP and the strategies employed by the pathogen to avert or subvert these responses, during the critical period between ingestion and the establishment of persistent infection in macrophages. PMID:24885748

2014-01-01

415

MglA Regulates Francisella tularensis subsp. novicida (Francisella novicida) Response to Starvation and Oxidative Stress?  

PubMed Central

MglA is a transcriptional regulator of genes that contribute to the virulence of Francisella tularensis, a highly infectious pathogen and the causative agent of tularemia. This study used a label-free shotgun proteomics method to determine the F. tularensis subsp. novicida (F. novicida) proteins that are regulated by MglA. The differences in relative protein amounts between wild-type F. novicida and the mglA mutant were derived directly from the average peptide precursor ion intensity values measured with the mass spectrometer by using a suite of mathematical algorithms. Among the proteins whose relative amounts changed in an F. novicida mglA mutant were homologs of oxidative and general stress response proteins. The F. novicida mglA mutant exhibited decreased survival during stationary-phase growth and increased susceptibility to killing by superoxide generated by the redox-cycling agent paraquat. The F. novicida mglA mutant also showed increased survival upon exposure to hydrogen peroxide, likely due to increased amounts of the catalase KatG. Our results suggested that MglA coordinates the stress response of F. tularensis and is likely essential for bacterial survival in harsh environments. PMID:17644593

Guina, Tina; Radulovic, Dragan; Bahrami, Arya J.; Bolton, Diana L.; Rohmer, Laurence; Jones-Isaac, Kendan A.; Chen, Jinzy; Gallagher, Larry A.; Gall