Open AccessNuclear translocation and DNAse I‐like enzymatic activity of Acinetobacter baumannii outer membrane protein A
Author(s) -
Choi Chul Hee,
Hyun Sung Hee,
Kim Jungmin,
Lee Yoo Chul,
Seol Sung Yong,
Cho Dong Taek,
Lee Je Chul
Publication year - 2008
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2008.01323.x
Subject(s) - biology , endonuclease , dna , intracellular , nuclease , cytosol , microbiology and biotechnology , acinetobacter baumannii , bacterial outer membrane , xenopus , enzyme , biochemistry , gene , bacteria , genetics , pseudomonas aeruginosa , escherichia coli
Abstract Acinetobacter baumannii outer membrane protein A (AbOmpA) is a potential virulence factor that induces host cell death. Based on previous findings that AbOmpA translocated into the nuclei of host cells, the cell‐death mechanism of AbOmpA through the nuclear targeting was investigated. Acinetobacter baumannii secreted AbOmpA in in vitro culture. The recombinant AbOmpA (rAbOmpA) was internalized by the host cells. The intracellular rAbOmpA was degraded into several forms of subfragments in the cytosol and then two subfragments of rAbOmpA translocated into the nuclei. The rAbOmpA exhibited the divalent cation‐dependent endonuclease activity. In an in vivo assay with microinjection of rAbOmpA into the nucleus of fertilized Xenopus laevis eggs, rAbOmpA degraded chromosomal DNA with the characteristic DNA ladders and induced degeneration of the embryos. These results suggest that AbOmpA translocates into the nuclei of host cells and degrades chromosomal DNA by DNAse I‐like enzymatic activity, which is a new pathogenic strategy of A. baumannii .