RESUMO
Here, we report the whole-genome sequences of two ovine-pathogenic Corynebacterium pseudotuberculosis isolates: strain 3/99-5, which represents the first C. pseudotuberculosis genome originating from the United Kingdom, and 42/02-A, the second from Australia. These genome sequences will contribute to the objective of determining the global pan-genome of this bacterium.
Assuntos
Infecções por Corynebacterium/veterinária , Corynebacterium pseudotuberculosis/genética , Genoma Bacteriano , Doenças dos Ovinos/microbiologia , Animais , Austrália , Sequência de Bases , Mapeamento Cromossômico , Infecções por Corynebacterium/microbiologia , Corynebacterium pseudotuberculosis/classificação , Corynebacterium pseudotuberculosis/isolamento & purificação , Linfadenite/microbiologia , Linfadenite/veterinária , Dados de Sequência Molecular , Escócia , Análise de Sequência de DNA , Ovinos/microbiologiaRESUMO
Corynebacterium pseudotuberculosis causes disease in several animal species, although distinct biovars exist that appear to be restricted to specific hosts. In order to facilitate a better understanding of the differences between biovars, we report here the complete genome sequence of the equine pathogen Corynebacterium pseudotuberculosis strain 1/06-A.
Assuntos
Corynebacterium pseudotuberculosis/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Genoma Bacteriano , Análise de Sequência de DNA , Animais , Infecções por Corynebacterium/veterinária , Corynebacterium pseudotuberculosis/isolamento & purificação , Doenças dos Cavalos/microbiologia , Cavalos , Dados de Sequência Molecular , América do NorteRESUMO
A two-step allele replacement mutagenesis procedure, using a conditionally replicating plasmid, was developed to allow the creation of targeted, marker-free mutations in Corynebacterium pseudotuberculosis. The relationship between homologous sequence length and recombination frequency was determined, and enhanced plasmid excision was observed due to the rolling-circle replication of the mutagenesis vector. Furthermore, an antibiotic enrichment procedure was applied to improve the recovery of mutants. Subsequently, as proof of concept, a marker-free, cp40-deficient mutant of C. pseudotuberculosis was constructed.
Assuntos
Corynebacterium pseudotuberculosis/genética , Marcação de Genes/métodos , Mutagênese Insercional/métodos , Alelos , Antibacterianos/farmacologia , DNA Bacteriano/química , DNA Bacteriano/genética , Deleção de Genes , Vetores Genéticos , Dados de Sequência Molecular , Plasmídeos , Seleção Genética , Análise de Sequência de DNARESUMO
Milk samples from 50 sheep on a single Scottish research farm were collected weekly for 10 wk postpartum. Samples were analyzed for somatic cell counts (SCC) each week and bacteriologic culture was done for 7 of the 10 wk. A total of 492 udder half samples were cultured, of which 467 had corresponding cell count data. Statistical analysis on complete SCC and culture data showed no association between SCC and bacterial isolation, even when more than 10 colonies of a single bacterial species were present. Only 3.6% of the samples were simultaneously positive for high count (> 10 colonies from 0.01 mL of milk) of any one bacterial species and high SCC (> 1 x 10(6)/mL). The bacteria recovered were: Staphylococcus equorum (19 times), S. xylosus (7 times), S. simulans (6 times), Streptococcus uberis (3 times) and other streptococci (4 times), Mannheimia (Pasteurella) haemolytica (2 times), Staphylococcus aureus (1 time), S. capitis (1 time), and Enterococcus faecium (1 time). There was an association between the test day and SCC, with higher SCC values in the first 2 wk. In addition, significantly higher SCC values were found in the oldest animals compared to the other age groups.