Search results for "bacteria."

Exiguobacterium pavilionensis str. N139, a halotolerant, UV-B and metal resistant bacteria from a high-altitude Andean lake

2016

We report the genome sequence of Exiguobacterium pavilionensis str. N139, isolated from a high-altitude Andean lake. The 2,952,588-bp genome contains one chromosome and three megaplasmids. The genome analysis suggests the presence of enzymes that confer E. pavilionensis str. N139 the ability to grow under multiple environmental extreme conditions, including high concentrations of different metals and high ultraviolet B radiation. Moreover, the regulation of its tryptophan biosynthesis suggests that novel pathways remain to be discovered, and that these pathways might be fundamental in the amino acid metabolism of the microbial community from Laguna Negra, Argentina .

Exploring the self-assembly of resorcinarenes : from molecular level interactions to mesoscopic structures

2012

Occurrence and virulence of Pseudoalteromonas spp. in cultured gilthead sea bream (Sparus aurata L.) and European sea bass (Dicentrarchus labrax L.).…

2007

During two long-term bacteriological surveys in European sea bass (Dicentrarchus labrax L.) and gilthead sea bream (Sparus aurata L.) culture facilities on the Spanish Mediterranean coast, four different species of Pseudoalteromonas were found in the internal organs of animals. Pseudoalteromonas undina, Pseudoalteromonas haloplanktis, P. espejiana and Pseudoalteromonas sp. were isolated from 9% out of 177 European sea bass and 11.7% out of 547 gilthead sea bream and they were recovered as pure cultures in 50% of isolations. Among fish with positive bacterial growth, Pseudoalteromonas was more prevalent in sea bass showing clinical signs (27.7%) and in gilthead sea bream without clinical sig…

Does the freshwater mussel Anodonta anatina remove the fish pathogen Flavobacterium columnare from water?

2021

AbstractGlobal decline of freshwater mussels (Unionoida) is threatening biodiversity and the essential ecosystem services that mussels provide. As filter-feeding organisms, freshwater mussels remove phytoplankton and suspended particles from the water. By filtering bacteria, freshwater mussels also decrease pathogen loads in the water. The objective of this study was to evaluate whether the common freshwater bivalve Anodonta anatina (duck mussel) could remove the bacterial fish pathogen Flavobacterium columnare from the water. Mussels reduced bacteria in both of the two experiments performed, so that the bacterial concentration at the end of the 96-h monitoring in mussel treatments was only…

Specific sequence elements in the 5′ untranslated regions of rbcL and atpB gene mRNAs stabilize transcripts in the chloroplast of Chlamydomonas reinh…

2001

Using a series of point mutations in chimeric reporter gene constructs consisting of the 5' regions of the Chlamydomonas chloroplast rbcL or atpB genes fused 5' to the coding sequence of the bacterial uidA (GUS) gene, RNA-stabilizing sequence elements were identified in vivo in the 5' untranslated regions (5' UTRs) of transcripts of the chloroplast genes rbcL and atpB in Chlamydomonas reinhardtii. In chimeric rbcL 5' UTR:GUS transcripts, replacement of single nucleotides in the 10-nt sequence 5'-AUUUCCGGAC-3', extending from positions +38 to +47 relative to the transcripts' 5' terminus, shortened transcript longevity and led to a reduction in transcript abundance of more than 95%. A similar…

HSP70 gene expression in Mytilus galloprovincialis hemocytes is triggered by moderate heat shock and Vibrio anguillarum, but not by V. splendidus or …

2005

Complete sequence of HSP70 cDNA from the mussel, Mytilus galloprovincialis was established before quantifying its expression following moderate heat shock or injection of heat-killed bacteria. HSP70 cDNA is comprised of 2378 bp including one ORF of 654 aa, with a predicted 70 bp 5'-UTR and a 343 bp 3'-UTR (GenBank, 18 Jan 05, AY861684). Alignment identity ranged from 89% for Crassostrea ariakensis to 72% for C. virginica. Curiously, HSP70 gene and cDNA sequences from M. galloprovincialis, deposited later (03 and 27 May), show only 73% identity with the present sequence. Meanwhile, characteristic motifs of the HSP70 family were located in conserved positions. Expression of HSP70 gene was qua…

UDP-glucose deficiency in a mutant cell line protects against glucosyltransferase toxins from Clostridium difficile and Clostridium sordellii.

1996

Abstract We have previously isolated a fibroblast mutant cell with high resistance to the two Rho-modifying glucosyltransferase toxins A and B of Clostridium difficile. We demonstrate here a low level of UDP-glucose in the mutant, which explains its toxin resistance since: (i) to obtain a detectable toxin B-mediated Rho modification in lysates of mutant cells, addition of UDP-glucose was required, and it promoted the Rho modification dose-dependently; (ii) high pressure liquid chromatography analysis of nucleotide extracts of cells indicated that the level of UDP-glucose in the mutant (0.8 nmol/106 cells) was lower than in the wild type (3.7 nmol/106 cells); and (iii) sensitivity to toxin B…

POOLED ESTIMATES OF INCIDENCE OF ENDOPHTHALMITIS AFTER INTRAVITREAL INJECTION OF ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR AGENTS WITH AND WITHOUT TOPI…

2017

Purpose: To assess the effect of topical antibiotic prophylaxis on postoperative endophthalmitis after intravitreal injection of anti-vascular endothelial growth factor agents.Methods: A systematic literature search was performed from inception to March 2016 using PubMed, Medline, Web of Science, Embase, and the Cochrane Library, to identify articles that reported cases of endophthalmitis after intravitreal injection of anti-vascular endothelial growth factor agents. We used a pooled analysis to estimate the incidence of cases of endophthalmitis who developed after injections performed with and without topical antibiotic prophylaxis. We used regression analysis to explore the effects of stu…

Staphylococcus aureus alpha toxin mediates polymorphonuclear leukocyte-induced vasocontraction and endothelial dysfunction.

2002

The effect of Staphylococcus aureus alpha toxin (alpha-toxin) on selectin-mediated neutrophil adhesion was investigated in polymorphonuclear leukocyte- (PMN) induced vasocontraction and endothelial dysfunction. Adherence of human PMNs to rat aortic endothelium increased significantly following stimulation of the endothelium with alpha-toxin (0.1, 0.5, and 1 microg/mL). This effect could be significantly attenuated by monoclonal antibodies directed against P-selectin or fucoidin, a carbohydrate known to block selectins. Unstimulated human PMNs (10(6)cells/mL) were added to organ chambers containing rat aortic rings stimulated with alpha-toxin (0.5 microg/mL). PMNs elicited a significant vaso…

Insertion of a malE B-Galactosidase fusion protein into the envelope of Escherichia coli disrupts biogenesis of outer membrane proteins and processin…

1982

The synthesis of a membrane-bound MalE ,B-galactosidase hybrid protein, when induced by growth of Escherichia coli on maltose, leads to inhibition of cell division and eventually a reduced rate of mass increase. In addition, the relative rate of synthesis of outer membrane proteins, but not that of inner membrane proteins, was reduced by about 50%o. Kinetic experiments demonstrated that this reduction coincided with the period of maximum synthesis of the hybrid protein (and another maltose-inducible protein, LamB). The accumulation of this abnormal protein in the envelope therefore appeared specifically to inhibit the synthesis, the assembly of outer membrane proteins, or both, indicating t…