title: First description of SHV-148 mediated extended-spectrum cephalosporin resistance among clinical isolates of Escherichia coli from India.
abstract: OBJECTIVE
  The present study was aimed to investigate the genetic context, association with IS26 and horizontal transmission of SHV-148 among Escherichia coli in Tertiary Referral Hospital of India.
  
  
  METHODS
  Phenotypic characterisation of extended-spectrum beta-lactamases (ESBLs) was carried out as per CLSI criteria. Molecular characterisation of blaSHVand integron was carried out by polymerase chain reaction (PCR) assay and confirmed by sequencing. Linkage of IS26 with blaSHV-148was achieved by PCR. Purified products were cloned on pGEM-T vector and sequenced. Strain typing was performed by pulsed field gel electrophoresis with Xba I digestion. Transferability experiment and antimicrobial susceptibility was performed.
  
  
  RESULTS
  A total of 33 isolates showed the presence of SHV-148 variant by sequencing and all were Class 1 integron borne. PCR and sequencing results suggested that all blaSHV-148 showed linkage with IS26 and were present in the upstream portion of the gene cassette and were also horizontally transferable through F type of Inc group. Susceptibility results suggest that tigecycline was most effective.
  
  
  CONCLUSIONS
  The present study reports for the first time of SHV-148 mediated extended spectrum cephalosporin resistance from India. Association of their resistance gene with IS26 and Class 1 integron and carriage within IncF plasmid signifies the potential mobilising unit for the horizontal transfer.
authors.forename: Anand Prakash
authors.initials: AP
authors.lastname: Maurya
authors.forename: Anupam
authors.initials: A
authors.lastname: Das Talukdar
authors.forename: Debadatta Dhar
authors.initials: DD
authors.lastname: Chanda
authors.forename: Atanu
authors.initials: A
authors.lastname: Chakravarty
authors.affiliation: Department of Microbiology, Assam University Silchar, Silchar, India.
authors.forename: Amitabha
authors.initials: A
authors.lastname: Bhattacharjee
mesh_terms: D000328:Adult; D018550:Cephalosporin Resistance; D004251:DNA Transposable Elements; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology*; D005260:Female; D022761:Gene Transfer, Horizontal; D006801:Humans; D007194:India; D032023:Integrons; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058889:Molecular Typing; D010957:Plasmids / Q000032:analysis / Q000145:classification; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D062606:Tertiary Care Centers; D055815:Young Adult; D001618:beta-Lactamases / Q000032:analysis* / Q000235:genetics
chemical_list: D004251:DNA Transposable Elements; C025580:endodeoxyribonuclease XBAI; D015252:Deoxyribonucleases, Type II Site-Specific; D001618:beta-Lactamases