title: YwdL in Bacillus cereus: its role in germination and exosporium structure.
abstract: In members of the Bacillus cereus group the outermost layer of the spore is the exosporium, which interacts with hosts and the environment. Efforts have been made to identify proteins of the exosporium but only a few have so far been characterised and their role in determining spore architecture and spore function is still poorly understood. We have characterised the exosporium protein, YwdL. ΔywdL spores have a more fragile exosporium, subject to damage on repeated freeze-thawing, although there is no evidence of altered resistance properties, and coats appear intact. Immunogold labelling and Western blotting with anti-YwdL antibodies identified YwdL to be located exclusively on the inner surface of the exosporium of B. cereus and B. thuringiensis. We conclude that YwdL is important for formation of a robust exosporium but is not required to maintain the crystalline assembly within the basal layer or for attachment of the hairy nap structure. ΔywdL spores are unable to germinate in response to CaDPA, and have altered germination properties, a phenotype that confirms the expected defect in localization of the cortex lytic enzyme CwlJ in the coat.
authors: Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, United Kingdom.
authors: Cassandra
authors: C
authors: Terry
authors: Andrew
authors: A
authors: Shepherd
authors: David S
authors: DS
authors: Radford
authors: Anne
authors: A
authors: Moir
authors: Per A
authors: PA
authors: Bullough
mesh_terms: D001409:Bacillus cereus / Q000737:chemistry* / Q000648:ultrastructure; D001426:Bacterial Proteins / Q000502:physiology* / Q000648:ultrastructure; D002473:Cell Wall; D018525:Germination; D046529:Microscopy, Electron, Transmission; D019441:Plant Epidermis; D013171:Spores, Bacterial / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D001426:Bacterial Proteins