Changing prevalent T serotypes and emm genotypes of Streptococcus pyogenes isolates from streptococcal toxic shock-like syndrome (TSLS) patients in Japan

Abstract

We surveyed T serotypes and emm genotypes of Streptococcus pyogenes isolates from streptococcal toxic shock-like syndrome (TSLS) patients. T1 (emm1) remained dominant through 1992 to 2000, but the dominant T3 (emm3.1) strains from 1992 to 1995 disappeared during 1996-2000. Strains of several emm genotypes emerged during 1996-2000, indicating alterations in the prevalent strains causing TSLS.Streptococcus pyogenes (group A streptococcus) is one of the most common human pathogens. It causes a wide array of infections, the most frequent of which is acute pharyngitis (strep throat). Many streptococcal virulence factors involved in these symptoms have been reported, including pyrogenic exotoxins (SpeA, SpeB and SpeC) and M protein. M protein, which is an important virulence factor of S. pyogenes, protects S. pyogenes from phagocytosis by polymorphonuclear leukocytes [1,2]. More than 90 of M protein serotypes have been identified, and a molecular approach to identification of emm (M protein) genes has also been documented. For example, emm1, emm2 and emm3 genes encode the M1, M2 and M3 proteins, respectively. In addition, the emm3.1 and emm22.2 belong to the emm3 and emm22 alleles, respectively (http ://www.cdc.gov/ncidod/biotech/strep/ emmtypes.html).T serotypes of S. pyogenes have also been important markers in the epidemiological investigation of S. pyogenes infections and more than 25 different T serotypes have been described [3,4]. The combination of T serotype and emm genotype allows the identification of strain diversity [5].From the late 1980s, streptococcal TSLS caused by S. pyogenes became a serious problem in both

Integrating proteomics, genomics, and bioinformatics tools to define unique features of the clonal M1T1 strain of Streptococcus pyogenes

“…doi:10.1016/j.ics.2005.11.083 GAS diseases; this hypothesis was indeed confirmed [4,5]. Still, since the M1T1 clone has persisted for over 20 years unlike other serotypes that tend to appear and disappear in a cyclic fashion [6,7], there must be something unique that led to the unusual success of this clone. In this article, we describe how we determined the unique features of this strain by integrating proteomics, genomics, and bioinformatics tools that spared us the need of fully sequencing the M1T1 genome.…”

Incompetence of Neutrophils to Invasive Group A streptococcus Is Attributed to Induction of Plural Virulence Factors by Dysfunction of a Regulator

“…The strains of emm1 genotype, among more than 100 emm genes encoding the serotype-determinant M protein, are the predominant cause of severe GAS infections in Japan [7]. Recently, GAS with diverse emm genotypes, especially, emm49 -genotype, have been isolated from patients of severe invasive GAS infections since 2000; however, these genotypes were not isolated before 1999 in Japan [8].…”

Long-term surveillance of invasive group A streptococcal disease in The Netherlands, 1994–2003

“…Only a few population‐based prospective epidemiological studies [4,16,18,20,26–28] have addressed the long‐term dynamics of invasive GAS disease and the contribution of ‘virulent’ M‐types over time. The present study analysed data obtained prospectively from a laboratory‐based nationwide surveillance system for invasive GAS infections that has been ongoing for a period of 10 years in The Netherlands.…”