Survey of emm -Like Gene Sequences from Pharyngeal Isolates of Group C and Group G Streptococci Collected in Spain

Abstract

We conducted a nationwide surveillance of the variable 5 emm-like (M-like protein gene) sequences from 214 pharyngeal group C and group G streptococci. Almost 75% of the isolates exhibited emm or emm-like sequences previously described. We identified six new 5 emm-like regions, and almost 23% of the isolates were nontypeable. Five emm-like sequences accounted for more than 50% of the isolates in group C and group G, suggesting horizontal gene transfer between strains of different species.

Distribution of emm Types and Genetic Characterization of the mgc Locus in Group G Streptococcus dysgalactiae subsp. equisimilis from a Hospital in Northern Taiwan

“…It is noted that stC839.0 was reported to be a dominant emm type from group C S. dysgalactiae subsp. equisimilis isolates in Spain and Australia (2,12). In our study, this type was also found in some (11.7%, 32/274) group G S. dysgalactiae subsp.…”

Prevalence of the M Protein Gene in Group C and Group G Streptococci Isolated from Patients in Thailand

“…A previous study in Thailand showed the predominant M protein type of GAS to be M93 (20.75z); other M types included M1, M44/61, and M25 (17). The M protein gene (emm and emmL) prevalence in GCS/GGS found in our study was higher than the 76.63z found in Spain (13). Of the blood-isolated GAS, GCS, and GGS, 90.0z, 84.6z, and 78.3z, respectively, had the M protein.…”

“…Although ＞ 200 emm types of GAS (15) and ＞60 emm types of GCS/GGS (7) have been reported, but the important types associated with invasive infection are unclear (7). M-like proteins may benefit GCS and GGS colonizing in the pharynx (13). The high diversity of the emm and emmL genes facilitates emm typing (13), and presents an alternative to serological typing, which has limitations that include nontypeable M proteins, specific antisera that are difficult to produce, and the potential for missing novel M-types.…”

“…The sizes of emm and emmL genes were similar in these 2 strains. Sizes of amplicons ranged 0.8-1.6 kb, depending on the M types (13).…”

Genetic Features of Clinical Isolates of Streptococcus dysgalactiae subsp. equisimilis Possessing Lancefield's Group A Antigen

“…The clinical manifestations included shock, hepatic insufficiency, renal failure, disseminated intravascular coagulation, erythematous rash, and soft-tissue necrosis. It has been suggested that the horizontal transfer of the emm sequences and the following recombination events occur among beta-hemolytic streptococci such as GAS, GCS, and GGS (1,24,25). Such a mechanism could be responsible for the development of gene mosaics and the evolution of the emm genes in beta-hemolytic streptococci (29).…”