Complete genome sequence of hypervirulent and outbreak-associated Acinetobacter baumannii strain LAC-4: epidemiology, resistance genetic determinants and potential virulence factors.
Acinetobacter baumannii is an important human pathogen due to its multi-drug resistance. In this study, the genome of an ST10 outbreak A. baumannii isolate LAC-4 was completely sequenced to better understand its epidemiology, antibiotic resistance genetic determinants and potential virulence factors. Compared with 20 other complete genomes of A. baumannii, LAC-4 genome harbors at least 12 copies of five distinct insertion sequences. It contains 12 and 14 copies of two novel IS elements, ISAba25 and ISAba26, respectively. Additionally, three novel composite transposons were identified: Tn6250, Tn6251 and Tn6252, two of which contain resistance genes. The antibiotic resistance genetic determinants on the LAC-4 genome correlate well with observed antimicrobial susceptibility patterns. Moreover, twelve genomic islands (GI) were identified in LAC-4 genome. Among them, the 33.4-kb GI12 contains a large number of genes which constitute the K (capsule) locus. LAC-4 harbors several unique putative virulence factor loci. Furthermore, LAC-4 and all 19 other outbreak isolates were found to harbor a heme oxygenase gene (hemO)-containing gene cluster. The sequencing of the first complete genome of an ST10 A. baumannii clinical strain should accelerate our understanding of the epidemiology, mechanisms of resistance and virulence of A. baumannii.
State Key Laboratory of Microbial Metabolism and School of Life Sciences &Biotechnology, Shanghai Jiaotong University, Shanghai, China.
Hong-Yu
HY
Ou
Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, USA.
Shan N
SN
Kuang
State Key Laboratory of Microbial Metabolism and School of Life Sciences &Biotechnology, Shanghai Jiaotong University, Shanghai, China.
Xinyi
X
He
Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, USA.
Brenda M
BM
Molgora
Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, USA.
Peter J
PJ
Ewing
State Key Laboratory of Microbial Metabolism and School of Life Sciences &Biotechnology, Shanghai Jiaotong University, Shanghai, China.
Zixin
Z
Deng
Department of Pathology, LAC+USC Medical Center, Los Angeles, California, USA.
Melanie
M
Osby
Human Health Therapeutics, National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.
Wangxue
W
Chen
Department of Biological Sciences, California State University Los Angeles, Los Angeles, California, USA.
H Howard
HH
Xu
D000151:Acinetobacter Infections / Q000453:epidemiology* / Q000235:genetics / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D001483:Base Sequence; D002876:Chromosomes, Bacterial / Q000235:genetics; D003198:Computer Simulation; D004251:DNA Transposable Elements / Q000235:genetics; D004196:Disease Outbreaks; D004352:Drug Resistance, Microbial / Q000235:genetics; D018432:Drug Resistance, Multiple / Q000235:genetics*; D056426:Genetic Loci; D016680:Genome, Bacterial; D044404:Genomic Islands / Q000235:genetics; D023281:Genomics; D006801:Humans; D015141:Los Angeles / Q000453:epidemiology; D008969:Molecular Sequence Data; D058885:Multilocus Sequence Typing; D016254:Mutagenesis, Insertional / Q000235:genetics; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014774:Virulence / Q000235:genetics; D037521:Virulence Factors / Q000235:genetics*
D004251:DNA Transposable Elements; D037521:Virulence Factors