Mutations in the gerP locus of Bacillus subtilis and Bacillus cereus affect access of germinants to their targets in spores

Behravan, J. and Chirakkal, H. and Masson, A. and Moir, A. (2000) Mutations in the gerP locus of Bacillus subtilis and Bacillus cereus affect access of germinants to their targets in spores. Journal of Bacteriology, 182 (7). pp. 1987-1994.

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Mutations in the gerP locus of Bacillus subtilis and Bacillus cereus affect access of germinants to their targets in spores.pdf

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The gerP1 transposon insertion mutation of Bacillus cereus is responsible for a defect in the germination response of spores to both L- alanine and inosine. The mutant is blocked at an early stage, before loss of heat resistance or release of dipicolinate, and the efficiency of colony formation on nutrient agar from spores is reduced fivefold. The protein profiles of alkaline-extracted spore coats and the spore cortex composition are unchanged in the mutant. Permeabilization of gerP mutant spores by coat extraction procedures removes the block in early stages of germination, although a consequence of the permeabilization procedure in both wild type and mutant is that late germination events are not complete. The complete hexacistronic operon that includes the site of insertion has been cloned and sequenced. Four small proteins encoded by the operon (GerPA, GerPD, GerPB, and GerPF) are related in sequence. A homologous operon (yisH-yisC) can be found in the Bacillus subtilis genome sequence; null mutations in yisD and yisF, constructed by integrational inactivation, result in a mutant phenotype similar to that seen in B. cereus, though somewhat less extreme and equally repairable by spore permeabilization. Normal rates of germination, as estimated by loss of heat resistance, are also restored to a gerP mutant by the introduction of a cote mutation, which renders the spore coats permeable to lysozyme. The B. subtilis operon is expressed solely during sporulation, and is sigma K-inducible. We hypothesize that the GerP proteins are important as morphogenetic or structural components of the Bacillus spore, with a role in the establishment of normal spore coat structure and/or permeability, and that failure to synthesize these proteins during spore formation limits the opportunity for small hydrophilic organic molecules, like alanine or inosine, to gain access to their normal target, the germination receptor, in the spore.

Item Type: Article
Additional Information: Cited By :67 Export Date: 16 February 2020 CODEN: JOBAA Correspondence Address: Moir, A.; Dept. of Molec. Biol./Biotechnol., University of Sheffield, Sheffield S10 2TN, United Kingdom; email:
Uncontrolled Keywords: alanine bacterial DNA bacterial protein dipicolinic acid inosine lysozyme article Bacillus cereus Bacillus subtilis bacterial spore colony formation controlled study DNA sequence gene insertion gene locus gene mutation nonhuman operon priority journal spore germination sporogenesis transposon Amino Acid Sequence Bacterial Proteins Cloning, Molecular Gene Expression Regulation, Bacterial Genes, Bacterial Heat Kinetics Molecular Sequence Data Muramidase Mutation Permeability Phenotype Picolinic Acids Sequence Alignment Spores, Bacterial Transcription Factors Bacteria (microorganisms) Posibacteria Prokaryota
Subjects: QW Microbiology and Immunology
Divisions: Mashhad University of Medical Sciences
Depositing User: mr lib7 lib7
Date Deposited: 30 Apr 2020 08:22
Last Modified: 30 Apr 2020 08:22

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