title: Involvement of O8-antigen in altering beta-lactam antibiotic susceptibilities in Escherichia coli.
abstract: In spite of being dispensable, O-antigens are believed to facilitate various cellular processes and alter antibiotic sensitivities. Escherichia coli K-12 (CS109) strains are lacking in O-antigens and are reported to be sensitive to antibiotics. To our surprise, E. coli 2443 (expressing O8-antigen) manifested two- to fourfold higher sensitivities toward penicillin and its derivatives than strain CS109. However, sensitivities toward other structurally unrelated antibiotics remained unchanged. To understand the rationale behind such observations, we replaced the rfb locus of strain 2443 with that of E. coli K-12. The beta-lactam sensitivities of 2443 cells with replaced rfb locus appeared to be identical to those for CS109. Therefore, it is quite reasonable to hypothesize the possible involvement of O8-antigen in beta-lactam sensitization.
authors.affiliation: Department of Biotechnology, Indian Institute of Technology, Kharagpur, West Bengal, India.
authors.forename: Sujoy K
authors.initials: SK
authors.lastname: Sarkar
authors.forename: Anindya S
authors.initials: AS
authors.lastname: Ghosh
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D019081:O Antigens / Q000235:genetics / Q000378:metabolism*; D047090:beta-Lactams / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D019081:O Antigens; D047090:beta-Lactams; C079397:rfb protein, Bacteria