부산대학교 도서관

The Dsb family of redox proteins catalyzes disulfide bond formation and isomerization. Since mutations indsbgenes change the conformation and stability of many extracytoplasmic proteins, and since many virulence factors of pathogenic bacteria are extracytoplasmic, inactivation ofdsbgenes often results in pathogen attenuation. This study investigated the role of 2 membrane-bound oxidoreductases, DsbB and DsbI, in theCampylobacter jejunioxidative Dsb pathway.Campylobactermutants, lacking DsbB or DsbI or both, were constructed by allelic replacement and used in the human intestinal epithelial T84 cell line for the gentamicin protection assay (invasion assay) and chicken colonization experiments. InC. colistrain 23/1, the inactivation of thedsbBordsbIgene separately did not significantly affect the colonization process. However, simultaneous disruption of both membrane-bound oxidoreductase genes significantly decreased the strain’s ability to colonize chicken intestines. Moreover,C. jejunistrain 81–176 with mutateddsbBordsbIgenes showed reduced invasion/intracellular survival abilities. No cells of the double mutants (dsbB−dsbI−) ofC. jejuni81–176 were recovered from human cells after 3 h of invasion.