Determination of M types of group A beta hemolytic streptococci by "emm" sequencing analyse

Following Streptococcus pyogenes (S. pyogenes) related throat infections, invasive diseases may occur due to several virulence factors. The most important virulence factor which leads to these diseases is known as M protein. Although many studies explore M types of S. pyogenes which lead throat infections in many countries, an accomplished research has not been found in our country yet. In this study it was aimed to determine M types of S.pyogenes which were isolated from the cultures of individuals who had throat infections, by using emm gene cycle-sequencing analyse. For this purpose, 114 S.pyogenes strains which were isolated from the throat cultures were sent to Gazi University, Hospital of Faculty of Medicine, Microbiology laboratory from different clinics and policlinics and identified with conventional and API methods, were included in this study."emm" specific PCR products were obtained in 97 of the strains (85%) using emmPl(5'- tatt(c/g)gcttagaaaattaa-3') and emmP2 (5'-gcaagttcttcagcttgttt-3') which were suggested by CDC. 91 of these emm types were sequenced by DNA cycle- sequencing analyse and local and global alignments which contain all sequences were performed by Clustal W vl.7 software. The BLAST server was used for the alignment. Phylogenetic dendrogram was drawn and emm types were identified. The emm types were 1, 3, 4, 6, 9, 11, 12, 14, 18, 22, 24, 29, 33, 43, 48, 75, 77, 78, 89, 90, 102, 112, 118. The most frequent emm types among these 23 different emm types were 12, 3, 1, 75, 29 respectively. The other 23 types which were not identified were accepted as nontypeable. M types. The most frequent 5 emm types were isolated from school age children who were under 10 years old. Besides, 15 of emm/M types including the most frequently seen emm 1, 3 and 12 which were determined in this study, were found that they were also in the contents of M types of 26 VV vaccine developed for GAS. For this reason, this vaccine is suggested to be effective as 76.9 % on all defined emm types in our study In conclusion, this study was carried out with limited samples and performed with strains which were isolated from patients who addressed to only one center. However, this study was the first study in our country which identified emm types of S. pyogenes. This study will meet the scientific deficit in our country and provide a scientific base which will lead to other researches in the future. The use of great deal of samples in these types of studies will help to determine the distribution of emm types according to different geographic regions. In addition, these researches are very important to provide the early determination of the distribution of invasive diseases in different regions and also their complications and to be the guide in vaccine development researches.