title: Molecular characterization and antibiotic resistance of clinical Streptococcus dysgalactiae subsp. equisimilis in Beijing, China.
abstract: Streptococcus dysgalactiae subsp. equisimilis (SDSE) is presently considered as a human pathogen associated with clinical infection. We characterized 56 SDSE isolates collected from two tertiary hospitals in Beijing, China. Sixteen distinct emm types/subtypes were detected, dominated by stG245.0 (32.1%), stG652.0 (10.7%), stG6.1 (10.7%) and stG485.0 (10.7%), and a novel stG840.0 variant type was identified. All isolates possessed virulence genes of sagA and scpA, and most carried slo (98.2%), ska (98.2%) and speG(dys) (35.7%). By multilocus sequence typing (MLST) analysis, 17 individual sequence types (STs) were distinguished, including 7 newly-identified STs (26.8% of isolates), of which ST127 (30.4%), ST7 (12.5%) and ST44 (10.7%) dominated. Meanwhile, pulsed-field gel electrophoresis (PFGE) analysis revealed 33 pattern types (PTs), which were further combined into 16 pattern clusters (PCs), and 59.3% of isolates were distributed into 2 dominant PCs. Notably, emm types had both close relationship and consistency with STs and PFGE PCs. Furthermore, of 56 SDSE isolates, the predominant antibiotic resistances were erythromycin (71.4%), clindamycin (71.4%) and tetracycline (60.7%). Correspondingly, the prevalent resistance genes of macrolide and tetracycline were erm(B) (78.6%) and tet(M) (73.2%). In addition, multiple point mutations of parC, one of fluoroquinolone resistance genes, were observed (accounting for 75%), and were divided into 12 types, with parC 07 as the predominant type. Our data suggested the wide molecular diversity and distinctive regional features of SDSE from clinical infection in Beijing, China.
authors.affiliation: Department of Laboratory Medicine, Civil Aviation General Hospital, Beijing 100123, China. Electronic address: zs25041@126.com.
authors.forename: Binghuai
authors.initials: B
authors.lastname: Lu
authors.affiliation: State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou 310003, China.
authors.forename: Yujie
authors.initials: Y
authors.lastname: Fang
authors.affiliation: Department of Laboratory Medicine, First Hospital, Peking University, Beijing 100034, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou 310003, China.
authors.forename: Baowei
authors.initials: B
authors.lastname: Diao
authors.affiliation: State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou 310003, China.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Du
authors.affiliation: State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou 310003, China.
authors.forename: Biao
authors.initials: B
authors.lastname: Kan
authors.affiliation: Department of Laboratory Medicine, Civil Aviation General Hospital, Beijing 100123, China.
authors.forename: Yanchao
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Department of Laboratory Medicine, Civil Aviation General Hospital, Beijing 100123, China.
authors.forename: Fengxia
authors.initials: F
authors.lastname: Zhu
authors.affiliation: Department of Laboratory Medicine, Civil Aviation General Hospital, Beijing 100123, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Li
authors.affiliation: State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Hangzhou 310003, China. Electronic address: wangduochun@icdc.cn.
authors.forename: Duochun
authors.initials: D
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015373:Bacterial Typing Techniques / Q000379:methods*; D002681:China; D024881:Drug Resistance, Bacterial; D005260:Female; D024841:Fluoroquinolones / Q000494:pharmacology; D014644:Genetic Variation; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing / Q000379:methods*; D013290:Streptococcal Infections / Q000382:microbiology*; D013291:Streptococcus / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D062606:Tertiary Care Centers; D037521:Virulence Factors / Q000235:genetics; D055815:Young Adult
chemical_list: D024841:Fluoroquinolones; D037521:Virulence Factors
keywords: Antibiotic resistance; China; Molecular characterization; S. dysgalactiae subsp. equisimilis