[Development of Staphylococcus Haemolyticus multilocus sequencing scheme and its use for molecular-epidemiologic analysis of strains isolated in hospitals in Russian federation in 2009-2010].

AIM

Development of Staphylococcus haemolyticus strain typing method based on multilocus sequencing for resolving problems of molecular epidemiology.

MATERIALS AND METHODS

102 strains of coagulase negative staphylococci (CNS) isolated in hospitals of various specialization in N. Novgorod and Moscow were studied. Species identification of strain was performed by using tuf gene fragment sequencing, S. haemolyticus strain differentiation--by MLST results. eBURST approach was used for cluster analysis of MLST data; structural changes in tagatose-6-phosphate kinase were studied by using InterProScan platform and SWISS-MODEL site programs; MLST scheme gene allele variability analysis was performed by using MEGA4.0 program package.

RESULTS

In the 102 strains sampled CNS was detected in 28 strains of the S. haemolyticus species. The MLST scheme developed for the first time for S. haemolyticus including mvaK, rphE, tphK, gtr, arcC, triA, aroE genes allowed the differentiation of the sampled strains by 11 genotypes. Strains with ST 3, 8, 6, 1, 4, 5 and 11 differed by highest epidemiologic significance. Cluster and phylogenetic analysis of the data obtained showed a high adaptive ability of the nosocomial S. haemolyticus strains. Multiresistance to antibacterial preparations was detected in the analyzed strains.

CONCLUSION

The MLST method developed was effective in the differentiation of S. haemolyticus strains that circulate in hospitals and threaten both neonates and hospitalized adult patients.