Phylogeny, Prevalence, and Shiga Toxin (Stx) Production of Clinical Escherichia coli O157 Clade 2 Strains Isolated in Shimane Prefecture, Japan.
Curr Microbiol
; 78(1): 265-273, 2021 Jan.
Article
en En
| MEDLINE
| ID: mdl-33095293
ABSTRACT
This study investigated the genetic and pathogenic variation of the subgroups of clade 2 strains of Shiga toxin (Stx)-producing Escherichia coli (STEC) O157. A total of 111 strains of STEC O157 isolated in Shimane prefecture, Japan, were classified in clade 2 (n = 39), clade 3 (n = 16), clade 4/5 (n = 3), clade 7 (n = 14), clade 8 (n = 17), and clade 12 (n = 22) by single-nucleotide polymorphism analysis and lineage-specific polymorphism assay-6. These results showed a distinct difference from our previous study in which clade 3 strains were the most prevalent strains in three other prefectures in Japan, indicating that the clade distribution of O157 strains was different in different geographic areas in Japan. Phylogenetic analysis using insertion sequence (IS) 629 distribution data showed that clade 2 strains formed two clusters, designated 2a and 2b. Stx2 production by cluster 2b strains was significantly higher than by cluster 2a strains (P < 0.01). In addition, population genetic analysis of the clade 2 strains showed significant linkage disequilibrium in the IS629 distribution of the strains in clusters 2a and 2b (P < 0.05). The ΦPT values calculated using the IS629 distribution data indicated that strains in clusters 2a and 2b were genetically different (P < 0.001). Cluster 2b strains are a highly pathogenic phylogenetic group and their geographic spread may be a serious public health concern.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Escherichia coli O157
/
Infecciones por Escherichia coli
Tipo de estudio:
Prevalence_studies
/
Risk_factors_studies
Límite:
Humans
País/Región como asunto:
Asia
Idioma:
En
Revista:
Curr Microbiol
Año:
2021
Tipo del documento:
Article
País de afiliación:
Japón