In:
Applied and Environmental Microbiology, American Society for Microbiology, Vol. 77, No. 19 ( 2011-10), p. 6755-6762
Abstract:
Acinetobacter baumannii is an important Gram-negative opportunistic pathogen causing nosocomial infections. The emergence of multiple-drug-resistant A. baumannii isolates has increased in recent years. Directed toward phage therapy, a lytic phage of A. baumannii , designated Abp53, was isolated from a sputum sample in this study. Abp53 has an isometric head and a contractile tail with tail fibers (belonging to Myoviridae ), a latent period of about 10 min, and a burst size of approximately 150 PFU per infected cell. Abp53 could completely lyse 27% of the A. baumannii isolates tested, which were all multiple drug resistant, but not other bacteria. Mg 2+ enhanced the adsorption and productivity of, and host lysis by, Abp53. Twenty Abp53 virion proteins were visualized in SDS-polyacrylamide gel electrophoresis, with a 47-kDa protein being the predicted major capsid protein. Abp53 has a double-stranded DNA genome of 95 kb. Sequence analyses of a 10-kb region revealed 8 open reading frames. Five of the encoded proteins, including 3 tail components and 2 hypothetical proteins, were similar to proteins encoded by A. baumannii strain ACICU. ORF1176 (one of the tail components, 1,176 amino acids [aa]), which is also similar to tail protein gp21 of Klebsiella phage phiKO2, contained repeated domains similar to those within the ACICU_02717 protein of A. baumannii ACICU and gp21. These findings suggest a common ancestry and horizontal gene transfer during evolution. As phages can expand the host range by domain duplication in tail fiber proteins, repeated domains in ORF1176 might have a similar significance in Abp53.
Type of Medium:
Online Resource
ISSN:
0099-2240
,
1098-5336
DOI:
10.1128/AEM.05116-11
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2011
detail.hit.zdb_id:
223011-2
detail.hit.zdb_id:
1478346-0
SSG:
12
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