title: Population dynamics of an Acinetobacter baumannii clonal complex during colonization of patients.
abstract: Acinetobacter baumannii has emerged as one of the leading pathogens causing hospital-acquired infection. The success of A. baumannii as a pathogen has to a large extent been attributed to its capacity to remodel its genome. Several major epidemic clonal complexes of A. baumannii spread across different health care facilities around the world, each of which contains a subset of diversified strains. However, little is known about the population dynamics during colonization of A. baumannii within hosts. Here, whole-genome sequencing was used to analyze population dynamics of A. baumannii strains isolated from a group of patients at different time points as well as from different sites of a particular patient. Seven out of nine of the sampled A. baumannii strains belonged to the international clone II (CC92 clonal complex). While the A. baumannii strains were found to be stable in three patients, there was a change of A. baumannii strains in one patient. Comparative genomic analysis revealed that the accessory genome of these strains contained a large set of virulence-encoding genes and these virulence factors might play a role in determining population dynamics. Microscale genome modification has been revealed by analysis of single nucleotide polymorphisms (SNPs) between A. baumannii strains isolated from the same patient. Parallel evolutionary traits have been observed during genome diversification when A. baumannii colonize in different patients. Our study suggested that both antibiotic usage and host environment might impose selective forces that drive the rapid adaptive evolution in colonizing A. baumannii.
authors.affiliation: Department of Emergency, First Affiliated Hospital of Guangxi Medical University, Nanning, People's Republic of China.
authors.forename: Hanchun
authors.initials: H
authors.lastname: Wen
authors.affiliation: Department of Emergency, First Affiliated Hospital of Guangxi Medical University, Nanning, People's Republic of China Department of Respiratory Disease, First Affiliated Hospital of Guangxi Medical University, Nanning, People's Republic of China.
authors.forename: Ke
authors.initials: K
authors.lastname: Wang
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore.
authors.forename: Martin
authors.initials: M
authors.lastname: Tay
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, New South Wales, Australia.
authors.forename: Federico M
authors.initials: FM
authors.lastname: Lauro
authors.affiliation: Department of Respiratory Disease, First Affiliated Hospital of Guangxi Medical University, Nanning, People's Republic of China.
authors.forename: Hong
authors.initials: H
authors.lastname: Huang
authors.affiliation: Department of Cell Biology and Genetics, Guangxi Medical University, Nanning, People's Republic of China.
authors.forename: Huayu
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning, People's Republic of China.
authors.forename: Hongjie
authors.initials: H
authors.lastname: Liang
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore Interdisciplinary Graduate School, Nanyang Technological University, Singapore.
authors.forename: Yichen
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore Costerton Biofilm Center, Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Michael
authors.initials: M
authors.lastname: Givskov
authors.affiliation: Department of Respiratory Disease, First Affiliated Hospital of Guangxi Medical University, Nanning, People's Republic of China chenyq0708@foxmail.com yangliang@ntu.edu.sg.
authors.forename: Yiqiang
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Singapore Centre on Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore School of Biological Sciences, Nanyang Technological University, Singapore chenyq0708@foxmail.com yangliang@ntu.edu.sg.
authors.forename: Liang
authors.initials: L
authors.lastname: Yang
mesh_terms: D000151:Acinetobacter Infections / Q000382:microbiology*; D040981:Acinetobacter baumannii / Q000145:classification* / Q000235:genetics / Q000254:growth & development*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D016680:Genome, Bacterial; D005838:Genotype; D006801:Humans; D008969:Molecular Sequence Data; D011157:Population Dynamics; D017422:Sequence Analysis, DNA; D013997:Time Factors
chemical_list: D004269:DNA, Bacterial