A. Petersohn et al., Identification of sigma(B)-dependent genes in Bacillus subtilis using a promoter consensus-directed search and oligonucleotide hybridization, J BACT, 181(18), 1999, pp. 5718-5724
A consensus-directed search for sigma(B) promoters was used to locate poten
tial candidates for new sigma(B)-dependent genes in Bacillus subtilis. Scre
ening of those candidates by oligonucleotide hybridizations with total RNA
from exponentially growing or ethanol-stressed cells of the wild type as we
ll as a sigB mutant revealed 22 genes that required sigma(B) for induction
by ethanol. Although almost 50% of the proteins encoded by the newly discov
ered sigma(B)-dependent stress genes seem to be membrane localized, biochem
ical functions have so far not been defined for any of the gene products. A
llocation of the genes to the sigma(B)-dependent stress regulon may indicat
e a potential function in the establishment of a multiple stress resistance
. AIdY and YhdF show similarities to NAD(P)-dependent dehydrogenases and Yd
bP to thioredoxins, supporting our suggestion that sigma(B)-dependent prote
ins may be involved in the maintenance of the intracellular redox balance a
fter stress.