title: Identification of aac(2')-I type b aminoglycoside-modifying enzyme genes in resistant Acinetobacter baumannii.
abstract: The aim of this study was to investigate the mechanism underlying the drug resistance of Acinetobacter baumannii toward aminoglycosides. A total of 32 A. baumannii strains were identified by molecular identification and subsequently isolated. The isolates were then amplified by polymerase chain reaction to analyze the 9 aminoglycoside-modifying enzyme genes and 7 16S rRNA methylase genes. Five types of aminoglycoside-modifying enzyme genes and 1 type of 16S rRNA methylase gene were detected in the 32 drug-resistant A. baumannii strains. Positive genes included 7 detection modes, of which the all-6-gene-positive mode aac(2')-Ib+aac(3)-I+aac(6')-Ib+ant(3'')-I+aph(3')-I+armA exhibited the largest number of strains (12, 37.5%). The resistance of A. baumannii against aminoglycosides resulted from the presence of 5 types of aminoglycoside-modifying enzyme genes and the 16S rRNA methylase gene armA. This study is the first to isolate the aac(2')-Ib aminoglycoside-modifying enzyme gene from A. baumannii in a domestic clinical setting.
authors: Department of Clinical Laboratory, Huai'an First Hospital Affiliated of Nanjing Medical University, Huai'an, China.
authors: T
authors: T
authors: Lin
authors: Department of Clinical Laboratory, Huai'an First Hospital Affiliated of Nanjing Medical University, Huai'an, China chaoguitang@163.com.
authors: C G
authors: CG
authors: Tang
authors: Department of Clinical Laboratory, Huai'an First Hospital Affiliated of Nanjing Medical University, Huai'an, China.
authors: Q H
authors: QH
authors: Li
authors: Department of Clinical Laboratory, Huai'an First Hospital Affiliated of Nanjing Medical University, Huai'an, China.
authors: J
authors: J
authors: Ji
authors: Department of Clinical Laboratory, Huai'an First Hospital Affiliated of Nanjing Medical University, Huai'an, China.
authors: H Y
authors: HY
authors: Ge
authors: Department of Clinical Laboratory, Huai'an First Hospital Affiliated of Nanjing Medical University, Huai'an, China.
authors: X Y
authors: XY
authors: Zhang
authors: Department of Clinical Laboratory, Huai'an First Hospital Affiliated of Nanjing Medical University, Huai'an, China.
authors: H P
authors: HP
authors: Sun
mesh_terms: D000123:Acetyltransferases / Q000235:genetics* / Q000378:metabolism; D040981:Acinetobacter baumannii / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D000617:Aminoglycosides / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D005820:Genetic Testing; D008826:Microbial Sensitivity Tests; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D000123:Acetyltransferases; C443113:aminoglycoside 2'-N-acetyltransferase