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111.
M. Linhová P. Patáková J. Lipovský P. Fribert L. Paulová M. Rychtera K. Melzoch 《Folia microbiologica》2010,55(4):340-344
Clostridium pasteurianum forms acetic and butyric acids in an initial growth phase, which is a typical feature of clostridial acetone-butanol fermentation
where an initial accumulation of acids is followed by production of solvents 1-butanol, acetone and ethanol. The initiation
of the solvent production coupled with endospore formation leads to decrease of cell-wall thickness; thinner cell wall is
more resistant against solvents and dyes. These changes can be observed by the method based on adaptation of Gram staining.
The cell wall of G+ bacteria allows the entry of hexidium iodide and rhodamine 123, whereas the outer membrane of G− bacteria does not allow the uptake and therefore G+ bacteria are stained with higher fluorescence intensity than G− bacteria. The ratio of fluorescence intensity (FI) to forward scatter (FSC) was determined to correspond to G+ bacteria when clostridia were producing less solvents. The significant drop of the ratio FI to FSC to the level corresponding
to G− bacteria is detected after initiation of solvent production. 相似文献
112.
Michelle Pacholec John E. Bleasdale Boris Chrunyk David Cunningham Declan Flynn Robert S. Garofalo David Griffith Matt Griffor Pat Loulakis Brandon Pabst Xiayang Qiu Brian Stockman Venkataraman Thanabal Alison Varghese Jessica Ward Jane Withka Kay Ahn 《The Journal of biological chemistry》2010,285(11):8340-8351
113.
Producing a robust phylogenetic reconstruction for Polychaeta using either morphological or molecular data sets has proven very difficult. There remain many conflicts between morphological analyses and hypotheses based on DNA data, the latter principally derived from 18S rRNA sequences. For the present study a data set covering a broad range of polychaete diversity was assembled, including 38 new sequences from 21 species. Besides available 18S rRNA data, five additional gene segments were examined: the D1 and D9-10 expansion regions of 28S rRNA, histone H3, snU2 RNA and cytochrome c oxidase subunit I. Maximum parsimony, maximum likelihood and Bayesian analyses were conducted.Annelida and Mollusca were reciprocally monophyletic in maximum likelihood analyses, but Polychaeta included a cephalopod in maximum parsimony analyses, and a patellogastropod in Bayesian analyses. When rooted on the Mollusca, optimal topologies from maximum likelihood analyses showed a recognisable basal group of taxa, including Oweniidae, Chaetopteridae and Amphinomidae. The six studied phyllodocidan families plus Orbiniidae (as the sister group of the scale-worms) formed the next most basal group. All analyses support the inclusion of Echiura, Clitellata and Siboglinidae within polychaetes. Bayesian analyses show Echiura as the sister group of Capitellidae, in agreement with previous 18S rRNA results, In contrast, Echiura formed the sister group to Trichobranchidae in maximum likelihood and maximum parsimony analyses.Supra-familial groupings consistently recovered within Polychaeta in the analyses are: (i) Terebellida without Ampharetidae; (ii) Scolecida (excepting Orbiniidae); (iii) Eunicidae, Lumbrineridae and Clitellata; and (iv) “Cirratuliformia” (including Sternaspidae) plus Sabellidae, Serpulidae and Spionidae. 相似文献
114.
115.
Judge J Kyriazakis I Greig A Davidson RS Hutchings MR 《Applied and environmental microbiology》2006,72(1):398-403
Rabbits have been increasingly linked to the persistence of paratuberculosis (Johne's disease) in domestic ruminants in the United Kingdom. The aims of this study were to determine the routes of intraspecies transmission of Mycobacterium avium subspecies paratuberculosis (MAP) in rabbits and to estimate the probability of transmission via each route, in order to gain understanding of the dynamics of MAP in this host. Rabbits were sampled from two sites where MAP had previously been isolated from the livestock and rabbit populations. No pathology was noted in any animals, but the overall prevalence of MAP in rabbits was high at both sites studied, 39.7% and 23.0%, respectively. MAP was isolated from the testes, uterus, placenta, fetuses, and milk. This is the first time that the bacterium has been isolated from any of these tissues in a nonruminant wildlife species. These results suggest that transmission may occur vertically, pseudovertically, and horizontally. Vertical, i.e., transplacental, and/or pseudo-vertical, i.e., through the ingestion of contaminated milk and/or feces, transmission occurred in 14% of offspring entering the population at 1 month of age. As infection via these routes is only possible from infected adult females, this equates to a probability of infection via this route of 0.326. Probability of infection via horizontal transmission (including interspecies transmission) occurred at up to 0.037 per month. The presence of these routes of transmission within natural rabbit populations will contribute to the maintenance of MAP infections within such populations and, therefore, the environment. 相似文献
116.
117.
Zhang H Loriaux P Eng J Campbell D Keller A Moss P Bonneau R Zhang N Zhou Y Wollscheid B Cooke K Yi EC Lee H Peskind ER Zhang J Smith RD Aebersold R 《Genome biology》2006,7(8):R73-12
There has been considerable recent interest in proteomic analyses of plasma for the purpose of discovering biomarkers. Profiling N-linked glycopeptides is a particularly promising method because the population of N-linked glycosites represents the proteomes of plasma, the cell surface, and secreted proteins at very low redundancy and provides a compelling link between the tissue and plasma proteomes. Here, we describe UniPep http://www.unipep.org--a database of human N-linked glycosites--as a resource for biomarker discovery. 相似文献
118.
Background
Hydrophobic protein from soybean (HPS) is an 8 kD cysteine-rich polypeptide that causes asthma in persons allergic to soybean dust. HPS is synthesized in the pod endocarp and deposited on the seed surface during development. Past evidence suggests that the protein may mediate the adherence or dehiscence of endocarp tissues during maturation and affect the lustre, or glossiness of the seed surface. 相似文献119.