title: Isolation and characterization of a virulent bacteriophage infecting Acinetobacter johnsonii from activated sludge.
abstract: A double-stranded DNA phage named AJO1, infecting Acinetobacter johnsonii, which plays an important role in wastewater treatment, was isolated from activated sludge in a full-scale municipal wastewater treatment plant. Based on morphological taxonomy, AJO1, with an icosahedral head 55 ± 2 nm in diameter and a non-contractile tail 8 ± 2 nm in length, was classified as a member of the Podoviridae family. Bacterial infection characteristics were as follows: no polyvalent infectivity, optimal multiplicity of infection of 10-2; eclipse and burst size of 30 min and 51.2 PFU-infected cells-1, respectively. It showed considerable infectivity under a neutral pH condition (pH 6.0-9.0) and relatively high temperature (55 °C). Whole-genome sequencing of AJO1 revealed a linearly permuted DNA (41 437 bp) carrying 54 putative open reading frames and 4 repeats. This is the first report of isolation of an A. johnsonii phage, whose bacteriophage distribution and population dynamics are not well known. The results of this study could contribute to subsequent research on the interaction between bacteriophages and their hosts during wastewater treatment. In addition, AJO1 may become a candidate for potential therapy against A. johnsonii infection in clinical applications, since this species is an opportunistic pathogen.
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, No.18 Shuangqing Road, Haidian District, 100085 Beijing, China.
authors.forename: Niansi
authors.initials: N
authors.lastname: Fan
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, No.18 Shuangqing Road, Haidian District, 100085 Beijing, China.
authors.forename: Rong
authors.initials: R
authors.lastname: Qi
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, No.18 Shuangqing Road, Haidian District, 100085 Beijing, China. Electronic address: yangmin@rcees.ac.cn.
authors.forename: Min
authors.initials: M
authors.lastname: Yang
mesh_terms: D000150:Acinetobacter / Q000821:virology*; D001435:Bacteriophages / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity*; D004279:DNA, Viral; D016679:Genome, Viral; D054884:Host-Pathogen Interactions; D006863:Hydrogen-Ion Concentration; D016366:Open Reading Frames; D017902:Podoviridae / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism / Q000648:ultrastructure; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology / Q000821:virology*; D014764:Viral Proteins / Q000235:genetics; D062065:Wastewater / Q000382:microbiology / Q000821:virology
chemical_list: D004279:DNA, Viral; D012722:Sewage; D014764:Viral Proteins; D062065:Wastewater
keywords: Acinetobacter johnsonii; Activated sludge; Bacterial infection; Bacteriophage; Isolation; Wastewater