Open AccessRoles of DacB and Spm Proteins in Clostridium perfringens Spore Resistance to Moist Heat, Chemicals, and UV Radiation
Author(s) -
Daniel Paredes-Sabja,
Nahid Sarker,
Barbara Setlow,
Peter Setlow,
Mahfuzur R. Sarker
Publication year - 2008
Publication title -
applied and environmental microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.552
H-Index - 324
eISSN - 1070-6291
pISSN - 0099-2240
DOI - 10.1128/aem.00169-08
Subject(s) - spore , clostridium perfringens , bacillus subtilis , food science , microbiology and biotechnology , endospore , water activity , radiation resistance , spore germination , biology , chemistry , water content , bacteria , radiation , genetics , physics , geotechnical engineering , quantum mechanics , engineering
Clostridium perfringens food poisoning is caused mainly by enterotoxigenic type A isolates that typically possess high spore heat resistance. Previous studies have shown that α/β-type small, acid-soluble proteins (SASP) play a major role in the resistance ofBacillus subtilis andC. perfringens spores to moist heat, UV radiation, and some chemicals. Additional major factors inB. subtilis spore resistance are the spore's core water content and cortex peptidoglycan (PG) structure, with the latter properties modulated by thespm anddacB gene products and the sporulation temperature. In the current work, we have shown that thespm anddacB genes are expressed only duringC. perfringens sporulation and have examined the effects ofspm anddacB mutations and sporulation temperature on spore core water content and spore resistance to moist heat, UV radiation, and a number of chemicals. The results of these analyses indicate that forC. perfringens SM101 (i) core water content and, probably, cortex PG structure have little if any role in spore resistance to UV and formaldehyde, presumably because these spores’ DNA is saturated with α/β-type SASP; (ii) spore resistance to moist heat and nitrous acid is determined to a large extent by core water content and, probably, cortex structure; (iii) core water content and cortex PG cross-linking play little or no role in spore resistance to hydrogen peroxide; (iv) spore core water content decreases with higher sporulation temperatures, resulting in spores that are more resistant to moist heat; and (v) factors in addition to SpmAB, DacB, and sporulation temperature play roles in determining spore core water content and thus, spore resistance to moist heat.