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Faecium Strains (faecium + strain)
Selected AbstractsEmtA, a rRNA methyltransferase conferring high-level evernimicin resistanceMOLECULAR MICROBIOLOGY, Issue 6 2001Paul A. Mann Enterococcus faecium strain 9631355 was isolated from animal sources on the basis of its resistance to the growth promotant avilamycin. The strain also exhibited high-level resistance to evernimicin, a drug undergoing evaluation as a therapeutic agent in humans. Ribosomes from strain 9631355 exhibited a dramatic reduction in evernimicin binding, shown by both cell-free translation assays and direct-binding assays. The resistance determinant was cloned from strain 9631355; sequence alignments suggested it was a methyltransferase and therefore it was designated emtA for evernimicin methyltransferase. Evernimicin resistance was transmissible and emtA was localized to a plasmid-borne insertion element. Purified EmtA methylated 50S subunits from an evernimicin-sensitive strain 30-fold more efficiently than those from a resistant strain. Reverse transcription identified a pause site that was unique to the 23S rRNA extracted from resistant ribosomes. The pause corresponded to methylation of residue G2470 (Escherichia coli numbering). RNA footprinting revealed that G2470 is located within the evernimicin-binding site on the ribosome, thus providing an explanation for the reduced binding of the drug to methylated ribosomes. [source] ORIGINAL ARTICLE: Effect of Lactobacillus fermentum and Enterococcus faecium strains on internal milieu, antioxidant status and body weight of broiler chickensJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2010M. Capcarova Summary The aim of the present study was to evaluate the functional efficiency of two probiotic strains Lactobacillus fermentum CCM 7158 and Enterococcus faecium M 74 given to the drinking water on internal milieu, antioxidant status and body weight of broiler chickens. The experiment was conducted on hybrid Hybro (n = 180). The feeding period lasted 42 days. Experimental chickens of E1 group received a probiotic preparation in drinking water with concentration of 1 × 109 colony forming units (CFU) of L. fermentum CCM 7158 in 1 g of nutrient medium and experimental chickens of E2 group concentration of 2 × 109 CFU of E. faecium M 74 in 1 g of nutrient medium. The control group of animals received water without any additives. Triglycerides content in serum mainly with L. fermentum strain against the control group was decreased. Calcium content in both experimental groups and significantly in E. faecium group was increased. Antioxidant status in both probiotic groups was significantly increased. The content of bilirubin in group with E. faecium M 74 was significantly increased. In conclusion, addition of a microbial feed additive (L. fermentum and E. faecium) increased serum calcium and iron level, decreased triglycerides content in blood and slightly increased body weight of broiler chickens. [source] Clinical isolates of Enterococcus faecium exhibit strain-specific collagen binding mediated by Acm, a new member of the MSCRAMM familyMOLECULAR MICROBIOLOGY, Issue 6 2003Sreedhar R. Nallapareddy Summary A collagen-binding adhesin of Enterococcus faecium, Acm, was identified. Acm shows 62% similarity to the Staphylococcus aureus collagen adhesin Cna over the entire protein and is more similar to Cna (60% and 75% similarity with Cna A and B domains respectively) than to the Enterococcus faecalis collagen-binding adhesin, Ace, which shares homology with Acm only in the A domain. Despite the detection of acm in 32 out of 32 E. faecium isolates, only 11 of these (all clinical isolates, including four vancomycin-resistant endocarditis isolates and seven other isolates) exhibited binding to collagen type I (CI). Although acm from three CI-binding vancomycin-resistant E. faecium clinical isolates showed 100% identity, analysis of acm genes and their promoter regions from six non-CI-binding strains identified deletions or mutations that introduced stop codons and/or IS elements within the gene or the promoter region in five out of six strains, suggesting that the presence of an intact functional acm gene is necessary for binding of E. faecium strains to CI. Recombinant Acm A domain showed specific and concentration-dependent binding to collagen, and this protein competed with E. faecium binding to immobilized CI. Consistent with the adherence phenotype and sequence data, probing with Acm-specific IgGs purified from anti-recombinant Acm A polyclonal rabbit serum confirmed the surface expression of Acm in three out of three collagen-binding clinical isolates of E. faecium tested, but in none of the strains with a non-functional pseudo acm gene. Introduction of a functional acm gene into two non-CI-binding natural acm mutant strains conferred a CI-binding phenotype, further confirming that native Acm is sufficient for the binding of E. faecium to CI. These results demonstrate that acm, which encodes a potential virulence factor, is functional only in certain infection-derived clinical isolates of E. faecium, and suggest that Acm is the primary adhesin responsible for the ability of E. faecium to bind collagen. [source] Increased conjugation frequencies in clinical Enterococcus faecium strains harbouring the enterococcal surface protein gene espCLINICAL MICROBIOLOGY AND INFECTION, Issue 6 2006B. Lund Abstract This study compared the in-vitro ability of Enterococcus faecium isolates of different origin to acquire vanA by conjugation in relation to the occurrence of the esp gene. In total, 29 clinical isolates (15/29 esp+), 30 normal intestinal microflora isolates (2/30 esp+) and one probiotic strain (esp -) were studied with a filter-mating assay. Conjugation events were confirmed by PCR and pulsed-field gel electrophoresis. Among the infection-derived isolates, the esp+ isolates had higher conjugation frequencies compared with esp - isolates (p < 0.001), with a median value of 6.4 × 10,6 transconjugants/donor. The probiotic strain was shown to acquire vanA vancomycin resistance in in-vitro filter mating experiments. [source] | ||||||||||