drs (Distantly related sic) gene polymorphisms among emm12-type Streptococcus pyogenes isolates

Abstract

Twenty-eight emm12-type Streptococcus pyogenes isolates from patients with invasive and noninvasive infections or from asymptomatic carriers were genetically typed. Sequencing of drs (distantly related sic [streptococcal inhibitor of complement]) genes identified two novel alleles and revealed a polymorphism for drs similar to that of sic. No association was observed between the five different drs alleles and the five restriction patterns of the vir regulon for the isolates studied. These data suggest that drs sequencing may be useful for further differentiation of S. pyogenes isolates with emm12 and identical vir regulon restriction patterns.

FIG. 1.

Restriction fragments of the vir(mga) regulon after digestion of the PCR product with HaeIII (lanes 2 to 6), BsiYI (lanes 8 to 12), and RsaI (lanes 14 to 18). Lanes 1, 7, 13, and 19, DNA molecular weight marker; lanes 2, 8, and 14, isolate AC-2353 (type 5); lanes 3, 9, and 15, isolate AC-2445 (type 4); lanes 4, 10, and 16, isolate AC-4098 (type 3); lanes 5, 11, and 17, isolate AC-1985 (type 2); lanes 6, 12, and 18, isolate AC-1460 (type 1).

FIG. 2.

Partial alignment of the nucleotide sequences of drs alleles drs12.01, drs12.02, drs12.03, drs12.04, drs.NS488, and drs.DRV1 and of the deduced protein sequences DRS12.01, DRS12.02, DRS12.03, DRS12.04, DRS.NS488, and DRS.DRV1. The allele drs12.01 serves as a reference.