B-203. Whole Genome Analysis of Streptococcus dysgalactiae subsp. Eequisimilis GGS_124

T. Miyoshi-Akiyama¹, Y. Shimomura¹, S. Murayama², K. Ubukata², J. Yagi³, T. Kirikae¹;
¹Intl. Med. Ctr. of Japan, Tokyo, JAPAN, ²Kitasato Inst. for Life Sci., Tokyo, JAPAN, ³Tokyo Women's Med. Univ., Tokyo, JAPAN.

Objective: Streptococcal toxic shock syndrome (STSS) is one of the life-threatening infectious diseases. Although STSS cases reported were caused by group A streptococcus (GAS), recent epidemiological studies indicated that the number of STSS cases caused by non-GAS streptococcus are increasing. One of the such Streptococcus is S. dysgalactiae subsp. equisimilis (SDEG), of which the genome has never been analyzed. In this study, we analyzed the whole genome of a SDEG strain named GGS124, chosen by the virulence in a mouse model. Results and Discussion: In the draft sequence data of the GGS124, the genome size is approximately 2.1Mbp. Most of the ORFs showed high similarity to those of .S. pyogenes.. Interestingly, approximately 10% of the ORFs of GGS124 showed similarity to those of .Streptococcus., other than .S. pyogenes.. Number of the putative lysogenic phage is 1. Among the pathogenic factors of S. pyogenes, streptococcal pyrogenic exotoxin B (cysteine proteinase) does not exist in the genome of GGS124, and GGS124 harbors only one superantigenic toxin similar to streptococcal pyrogenic exotoxin G (spegg). The spegg gene is not located in any genetic mobile elements suggesting that spegg is a direct progenitor of the founder of superantigenic toxin in Streptococcus.