Previous Article | Next Article ![]()
Appl. Environ. Microbiol., 10 1995, 3633-3638, Vol 61, No. 10
DL Popham, S Sengupta and P Setlow
Spores of a Bacillus subtilis strain with an insertion mutation in the dacB
gene, which codes for an enzyme involved in spore cortex biosynthesis, have
a higher core water content than wild-type spores. Spores lacking the two
major alpha/beta-type small, acid-soluble proteins (SASP) (termed
alpha-beta- spores) have the same core water content as do wild-type
spores, but alpha-beta- dacB spores had more core water than did dacB
spores. The resistance of alpha-beta-, alpha- beta- dacB, dacB, and
wild-type spores to dry and moist heat, hydrogen peroxide, and UV radiation
has been determined, as has the role of DNA damage in spore killing by
moist heat and hydrogen peroxide. These data (i) suggest that core water
content has little if any role in spore UV resistance and are consistent
with binding of alpha/beta-type SASP to DNA being the major mechanism
providing protection to spores from UV radiation; (ii) suggest that binding
of alpha/beta-type SASP to DNA is the major mechanism unique to spores
providing protection from dry heat; (iii) suggest that spore resistance to
moist heat and hydrogen peroxide is affected to a large degree by the core
water content, as increased core water resulted in large decreases in spore
resistance to these agents; and (iv) indicate that since this decreased
resistance (i.e., in dacB spores) is not associated with increased spore
killing by DNA damage, spore DNA must normally be extremely well protected
against such damage, presumably by the saturation of spore DNA by
alpha/beta-type SASP.
Copyright © 1995, American Society for Microbiology
Heat, hydrogen peroxide, and UV resistance of Bacillus subtilis spores with increased core water content and with or without major DNA-binding proteins
Department of Biochemistry, University of Connecticut Health Center, Farmington 06030, USA.
This article has been cited by other articles:
| J. Bacteriol. | Microbiol. Mol. Biol. Rev. | Eukaryot. Cell | All ASM Journals |
|---|