title: Mechanisms of tigecycline resistance among Klebsiella pneumoniae clinical isolates.
abstract: Of 26 tigecycline-nonsusceptible Klebsiella pneumoniae (TNSKP) clinical isolates, 25 had nonsynonymous mutations in ramR and/or acrR (23 in ramR and 10 in acrR). Eight TNSKP isolates possessed overexpression of ramA, acrB, rarA, and oqxB simultaneously, while 8 and 1 TNSKP strains had upregulation of ramA and acrB and of rarA and oqxB, respectively. Thus, resistance mechanisms of 9 TNSKP isolates cannot be explained by the present pathways. This study underscores the role of RamA in TNSKP and suggests the presence of novel tigecycline resistance mechanisms.
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China.
authors.forename: Zi-Ke
authors.initials: ZK
authors.lastname: Sheng
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China.
authors.forename: Fupin
authors.initials: F
authors.lastname: Hu
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China.
authors.forename: Weixia
authors.initials: W
authors.lastname: Wang
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China.
authors.forename: Qinglan
authors.initials: Q
authors.lastname: Guo
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China.
authors.forename: Xiaogang
authors.initials: X
authors.lastname: Xu
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China.
authors.forename: Demei
authors.initials: D
authors.lastname: Zhu
authors.affiliation: Institute of Antibiotics, Huashan Hospital, Fudan University, Shanghai, China Key Laboratory of Clinical Pharmacology of Antibiotics, Ministry of Health, Shanghai, China mgwang@fudan.edu.cn.
authors.forename: Minggui
authors.initials: M
authors.lastname: Wang
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D006801:Humans; D007710:Klebsiella Infections / Q000188:drug therapy / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D026901:Membrane Transport Proteins / Q000235:genetics*; D008826:Microbial Sensitivity Tests; D008911:Minocycline / Q000031:analogs & derivatives* / Q000494:pharmacology; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics*; D000078304:Tigecycline
chemical_list: D000900:Anti-Bacterial Agents; D026901:Membrane Transport Proteins; D008911:Minocycline; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D000078304:Tigecycline; C477884:AcrR protein, Klebsiella pneumoniae