title: Molecular analysis of β-lactamase genes to understand their differential expression in strains of Yersinia enterocolitica biotype 1A.
abstract: Beta-lactams are used as major therapeutic agents against a number of infectious agents. Due to widespread use of β-lactams, β-lactamases have evolved at a rapid pace leading to treatment failures. Yersinia enterocolitica causes many gastrointestinal problems. It is an extremely heterogeneous species comprising more than fifty serotypes and six biotypes which differ in their ecological niches, geographical distribution and pathogenic potential. Though biotype 1A strains have been associated with outbreaks of Yersiniosis, there has been a controversy regarding their pathogenicity. The strains of Y. enterocolitica isolated from India belonged to biotype 1A and possessed genes for two β-lactamases namely, blaA and blaB. An earlier study by us reported differential expression of blaA by strains of Y. enterocolitica biotype 1A. The present study has been carried out to understand the molecular bases which regulate the expression of blaA in Y. enterocolitica biotype 1A. We concluded that six types of blaA variants were present in strains of biotype 1A. Neither amino acid substitutions in blaA nor mutations in promoter regions of blaA contributed to differential expression of blaA in Y. enterocolitica biotype 1A. Rather, the secondary structures attained by mRNA of blaA might underlie the differential expression of blaA in Y. enterocolitica.
authors.affiliation: Department of Microbiology, University of Delhi South Campus, New Delhi, India.
authors.forename: Neelja
authors.initials: N
authors.lastname: Singhal
authors.affiliation: Department of Biophysics, University of Delhi South Campus, New Delhi, India.
authors.forename: Manish
authors.initials: M
authors.lastname: Kumar
authors.affiliation: Department of Microbiology, University of Delhi South Campus, New Delhi, India.
authors.forename: Jugsharan Singh
authors.initials: JS
authors.lastname: Virdi
mesh_terms: D019943:Amino Acid Substitution / Q000235:genetics; D004196:Disease Outbreaks; D015870:Gene Expression / Q000235:genetics*; D007194:India; D009154:Mutation / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D065288:Serogroup; D015008:Yersinia enterocolitica / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D001618:beta-Lactamases