title: Isolation and characterization of ZZ1, a novel lytic phage that infects Acinetobacter baumannii clinical isolates.
abstract: BACKGROUND
  Acinetobacter baumannii, a significant nosocomial pathogen, has evolved resistance to almost all conventional antimicrobial drugs. Bacteriophage therapy is a potential alternative treatment for multidrug-resistant bacterial infections. In this study, one lytic bacteriophage, ZZ1, which infects A. baumannii and has a broad host range, was selected for characterization.
  
  
  RESULTS
  Phage ZZ1 and 3 of its natural hosts, A. baumanni clinical isolates AB09V, AB0902, and AB0901, are described in this study. The 3 strains have different sensitivities to ZZ1, but they have the same sensitivity to antibiotics. They are resistant to almost all of the antibiotics tested, except for polymyxin. Several aspects of the life cycle of ZZ1 were investigated using the sensitive strain AB09V under optimal growth conditions. ZZ1 is highly infectious with a short latent period (9 min) and a large burst size (200 PFU/cell). It exhibited the most powerful antibacterial activity at temperatures ranging from 35°C to 39°C. Moreover, when ZZ1 alone was incubated at different pHs and different temperatures, the phage was stable over a wide pH range (4 to 9) and at extreme temperatures (between 50°C and 60°C). ZZ1 possesses a 100-nm icosahedral head containing double-stranded DNA with a total length of 166,682 bp and a 120-nm long contractile tail. Morphologically, it could be classified as a member of the Myoviridae family and the Caudovirales order. Bioinformatic analysis of the phage whole genome sequence further suggested that ZZ1 was more likely to be a new member of the Myoviridae phages. Most of the predicted ORFs of the phage were similar to the predicted ORFs from other Acinetobacter phages.
  
  
  CONCLUSIONS
  The phage ZZ1 has a relatively broad lytic spectrum, high pH stability, strong heat resistance, and efficient antibacterial potential at body temperature. These characteristics greatly increase the utility of this phage as an antibacterial agent; thus, it should be further investigated.
authors: Department of Pathogen Biology, Basic Medical College of Zhengzhou University, Zhengzhou, P R China.
authors: Jing
authors: J
authors: Jin
authors: Zhen-Jiang
authors: ZJ
authors: Li
authors: Shu-Wei
authors: SW
authors: Wang
authors: Shan-Mei
authors: SM
authors: Wang
authors: De-Hai
authors: DH
authors: Huang
authors: Ya-Hui
authors: YH
authors: Li
authors: Yun-Yun
authors: YY
authors: Ma
authors: Jin
authors: J
authors: Wang
authors: Fang
authors: F
authors: Liu
authors: Xiang-Dong
authors: XD
authors: Chen
authors: Guang-Xing
authors: GX
authors: Li
authors: Xiao-Ting
authors: XT
authors: Wang
authors: Zhong-Quan
authors: ZQ
authors: Wang
authors: Guo-Qiang
authors: GQ
authors: Zhao
mesh_terms: D000151:Acinetobacter Infections / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000187:drug effects / Q000302:isolation & purification / Q000821:virology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001435:Bacteriophages / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology* / Q000648:ultrastructure; D017899:Caudovirales / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology / Q000648:ultrastructure; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D023061:Gene Order; D016679:Genome, Viral; D058507:Host Specificity; D006801:Humans; D006863:Hydrogen-Ion Concentration; D050296:Microbial Viability / Q000187:drug effects / Q000528:radiation effects; D008969:Molecular Sequence Data; D017900:Myoviridae / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology / Q000648:ultrastructure; D016366:Open Reading Frames; D017422:Sequence Analysis, DNA; D013696:Temperature; D014771:Virion / Q000648:ultrastructure
chemical_list: D000900:Anti-Bacterial Agents; D004279:DNA, Viral