Format

Send to

Choose Destination
J Bacteriol. 2009 Nov;191(21):6501-12. doi: 10.1128/JB.00767-09. Epub 2009 Aug 28.

Cell wall hydrolases affect germination, vegetative growth, and sporulation in Streptomyces coelicolor.

Author information

1
Department of Biology and Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.

Abstract

Peptidoglycan is a major cell wall constituent of gram-positive bacteria. It is a dynamic macromolecule that is actively remodeled to enable cell growth and differentiation through a tightly choreographed interplay of hydrolytic and biosynthetic enzyme activities. The filamentous bacterium Streptomyces coelicolor has a complex life cycle that likely requires considerable cell wall remodeling to enable both extension of vegetative hyphae and formation of differentiated cell types. In silico analysis of the S. coelicolor genome enabled identification of 56 candidate cell wall hydrolase genes. We found that seven of these genes shared a highly conserved 5' untranslated region and were expressed during both vegetative growth and sporulation; four of these genes were selected for more extensive biochemical and biological characterization. The proteins encoded by these genes, termed RpfA, SwlA, SwlB, and SwlC, were confirmed to be hydrolytic enzymes, as they could efficiently cleave S. coelicolor cell walls. Phenotypic analyses revealed that these enzymes are important throughout development; deletion of each hydrolase gene resulted in a mutant strain that was heat sensitive, defective in spore formation, and either altered in vegetative growth or delayed in spore germination. Our results indicate that these enzymes play key roles at multiple stages in the growth and development of S. coelicolor, highlighting both the lack of redundancy in hydrolase activity and the importance of cell wall remodeling in the S. coelicolor life cycle.

PMID:
19717604
PMCID:
PMC2795291
DOI:
10.1128/JB.00767-09
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center