RESUMO
Enterococcus faecium NRRL B-2354 is a surrogate microorganism used in place of pathogens for validation of thermal processing technologies and systems. We evaluated the safety of strain NRRL B-2354 based on its genomic and functional characteristics. The genome of E. faecium NRRL B-2354 was sequenced and found to comprise a 2,635,572-bp chromosome and a 214,319-bp megaplasmid. A total of 2,639 coding sequences were identified, including 45 genes unique to this strain. Hierarchical clustering of the NRRL B-2354 genome with 126 other E. faecium genomes as well as pbp5 locus comparisons and multilocus sequence typing (MLST) showed that the genotype of this strain is most similar to commensal, or community-associated, strains of this species. E. faecium NRRL B-2354 lacks antibiotic resistance genes, and both NRRL B-2354 and its clonal relative ATCC 8459 are sensitive to clinically relevant antibiotics. This organism also lacks, or contains nonfunctional copies of, enterococcal virulence genes including acm, cyl, the ebp operon, esp, gelE, hyl, IS16, and associated phenotypes. It does contain scm, sagA, efaA, and pilA, although either these genes were not expressed or their roles in enterococcal virulence are not well understood. Compared with the clinical strains TX0082 and 1,231,502, E. faecium NRRL B-2354 was more resistant to acidic conditions (pH 2.4) and high temperatures (60°C) and was able to grow in 8% ethanol. These findings support the continued use of E. faecium NRRL B-2354 in thermal process validation of food products.
Assuntos
Enterococcus faecium/genética , Enterococcus faecium/efeitos da radiação , Microbiologia de Alimentos/métodos , Esterilização/métodos , Fatores de Virulência/genética , Cromossomos Bacterianos , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , Enterococcus faecium/patogenicidade , Genoma Bacteriano , Dados de Sequência Molecular , Tipagem Molecular , Fases de Leitura Aberta , Plasmídeos , Análise de Sequência de DNARESUMO
Enterococcus faecalis ATCC 29212, a vancomycin-sensitive strain, has been extensively used as a representative control strain for clinical and laboratory experiments. Here we report the draft genome and annotation of this strain, containing 3,027,060 bp, with a G+C content of 37.2% in 126 contigs (≥ 500 bp).
Assuntos
DNA Bacteriano/química , DNA Bacteriano/genética , Enterococcus faecalis/genética , Genoma Bacteriano , Análise de Sequência de DNA , Técnicas Bacteriológicas/normas , Dados de Sequência Molecular , Controle de QualidadeRESUMO
Herein we report the first genome sequence for Lactobacillus florum. L. florum 2F was isolated from Valencia orange leaves and is fructophilic, like other strains of this species. The draft genome of L. florum 2F contains 1,261,842 bp with a G+C content of 41.5% in 46 contigs (≥500 bp).