title: Molecular and in silico analysis of a new plasmid-mediated AmpC β-lactamase (CMH-2) in clinical isolates of Klebsiella pneumoniae.
abstract: Two Klebsiella strains isolated from urine samples were positive for blaAmpCby PCR and showed sequence similarity with CMH-1 (98.6%) after sequencing. It also shares 82% similarity with ACT-1, 85% with MIR-1 and 81% with the chromosomal AmpC gene of Enterobacter cloacae. This gene was associated with the plasmid of IncK type. It has an open reading frame of 381 amino acid with four amino acid substitutions at position D144A, C189R, Q192E, and A195T as compared to CMH-1. When expressed in E.coli DH5α and E.coli strain B, this β-lactamase conferred resistance to cefotaxime, ceftriaxone and ceftazidime. In addition, both in vitro and in silico analysis revealed that this cephalosporinase was inhibited by cefepime and carbapenem group of drugs. Therefore, this new plasmid-encoded AmpC type β-lactamase gene was designated as CMH-2.
authors.affiliation: Department of Microbiology, Assam University, Silchar 788011, India.
authors.forename: Birson
authors.initials: B
authors.lastname: Ingti
authors.affiliation: Bioinformatics Centre, Assam University, Silchar 7880111, India.
authors.forename: Monjur Ahmed
authors.initials: MA
authors.lastname: Laskar
authors.affiliation: Department of Chemistry, Assam University, Silchar 788011, India.
authors.forename: Sudip
authors.initials: S
authors.lastname: Choudhury
authors.affiliation: Department of Microbiology, Assam University, Silchar 788011, India.
authors.forename: Anand Prakash
authors.initials: AP
authors.lastname: Maurya
authors.affiliation: Department of Microbiology, Assam University, Silchar 788011, India.
authors.forename: Deepjyoti
authors.initials: D
authors.lastname: Paul
authors.affiliation: Bioinformatics Centre, Assam University, Silchar 7880111, India.
authors.forename: Anupam Das
authors.initials: AD
authors.lastname: Talukdar
authors.affiliation: Bioinformatics Centre, Assam University, Silchar 7880111, India.
authors.forename: Manabendra Dutta
authors.initials: MD
authors.lastname: Choudhury
authors.affiliation: Department of Microbiology, Silchar Medical College and Hospital, Silchar 788014, India.
authors.forename: Debadatta
authors.initials: D
authors.lastname: Dhar
authors.affiliation: Department of Microbiology, Silchar Medical College and Hospital, Silchar 788014, India.
authors.forename: Atanu
authors.initials: A
authors.lastname: Chakravarty
authors.affiliation: Department of Microbiology, Assam University, Silchar 788011, India. Electronic address: ab0404@gmail.com.
authors.forename: Amitabha
authors.initials: A
authors.lastname: Bhattacharjee
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics*; D020134:Catalytic Domain; D003198:Computer Simulation; D024881:Drug Resistance, Bacterial / Q000235:genetics; D006801:Humans; D007710:Klebsiella Infections / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000201:enzymology / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics*; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D047090:beta-Lactams; C048795:AmpC beta-lactamases; D001618:beta-Lactamases