1887

Abstract

Summary: subsp. (formerly ) is the causative agent of pasteurellosis or pseudotuberculosis in warm water marine fish. Enzymes which neutralize reactive oxygen species, produced during aerobic metabolism or during respiratory burst in fish macrophages, are important virulence factors in many pathogens. This study characterizes a periplasmic superoxide dismutase (SOD) and a cytoplasmic catalase in Purification and partial amino-terminal sequencing confirmed the SOD to be iron-cofactored, with a high degree of homology to other bacterial FeSODs. The SOD was common to all strains analysed in terms of type, location and activity, whilst the catalase varied in activity between strains. The catalase was constitutively expressed, but the SOD appeared to be repressed under low oxygen conditions. In spite of the presence of a periplasmic SOD, was susceptible to killing by exogenous superoxide anion generated in a cell-free system. Addition of exogenous SOD to this system did not abolish the bactricidal effect; however, addition of catalase was protective. These results suggest that lack of periplasmic catalase may be implicated in susceptiblity to killing by reactive oxygen species.

Loading

Article metrics loading...

/content/journal/micro/10.1099/13500872-145-2-483
1999-02-01
2019-11-22
Loading full text...

Full text loading...

http://instance.metastore.ingenta.com/content/journal/micro/10.1099/13500872-145-2-483
Loading
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error