Background
Streptococcus agalactiae (GBS) are the major cause of serious diseases of newborns and adults. Genome of GBS contains two variants of pathogenicity island PAI-A and PAI-A1 associated with sspB1 and sspB1a, respectively.
sspB1 was not found in the genomes of strains from Moscow (Russia), the United Kingdom, Germany, Portugal, Angola, USA, and the Czech Republic. However, this gene was localized in 9% of GBS strains from St Petersburg (Russia). Distribution of sspB1a was 27-30% among GBS strains from various countries (Kuleshevich E. et al 2017; Kuleshevich E. et al 2021).
The aim of this investigation was to determine the correlation between clonal complexes and the presence of sspB1 and sspB1a among GBS human strains from Genbank.
Methods
The search of sspB1 and sspB1a was performed by using computer program BLAST among GBS human strains, which genomes presented in Genbank on 31 May 2021.
Sequence types were determined by using Public databases for molecular typing and microbial genome diversity (https://pubmlst.org/organisms/streptococcus-agalactiae).
Results
sspB1 was found in 49 strains out of 996 (4.9%). Genomes of 299 strains out of 996 (30.0%) contained sspB1a. sspB1 and sspB1a was not found in genomes of the most strains (more than 70%) of clonal complexes 2, 12, 17, and 23. However, 84% GBS human strains of clonal complex CC19 contained sspB1a.
Conclusions
The distribution of sspB1 and sspB1a correlates with previous results (Kuleshevich E. et al 2017). There is the correlation between GBS clonal complex CC19 and the presence of sspB1a.