Previous Article | Next Article ![]()
Journal of Bacteriology, July 2001, p. 4364-4373, Vol. 183, No. 14
School of Biological Sciences, Royal Holloway
University of London, Egham, Surrey TW20 0EX,1
and Department of Chemistry, University of York, York Y010
5DD,2 United Kingdom
Received 20 February 2001/Accepted 25 April 2001
During spore formation in Bacillus subtilis, the
SpoIVB protein is a critical component of the
0021-9193/01/$04.00+0 DOI: 10.1128/JB.183.14.4364-4373.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
The PDZ Domain of the SpoIVB Serine Peptidase
Facilitates Multiple Functions
K
regulatory checkpoint. SpoIVB has been shown to be a serine peptidase that is synthesized in the spore chamber and which self-cleaves, releasing active forms. These forms can signal proteolytic processing of the transcription factor
K in the outer mother cell
chamber of the sporulating cell. This forms the basis of the
K checkpoint and ensures accurate
K-controlled gene expression. SpoIVB has also been shown
to activate a second distinct process, termed the second function,
which is essential for the formation of heat-resistant spores. In
addition to the serine peptidase domain, SpoIVB contains a PDZ domain. We have altered a number of conserved residues in the PDZ domain by
site-directed mutagenesis and assayed the sporulation phenotype and
signaling properties of mutant SpoIVB proteins. Our work has revealed
that the SpoIVB PDZ domain could be used for up to four distinct
processes, (i) targeting of itself for trans
proteolysis, (ii) binding to the protease inhibitor BofC, (iii)
signaling of pro-
K processing, and (iv) signaling of the
second function of SpoIVB.
*
Corresponding author. Mailing address: School of
Biological Sciences, Royal Holloway University of London, Egham, Surrey
TW20 0EX, United Kingdom. Phone: 01784-443760. Fax: 01784-434326. E-mail: s.cutting{at}rhul.ac.uk.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»