Processing of the mother-cell sigma factor, sigma K, may depend on events occurring in the forespore during Bacillus subtilis development.

• DOI: 10.1073/pnas.87.24.9722
• Publication Date: 2006-05-31T11:32:52Z
• Authors: S Lu; R Halberg; L Kroos
• Keywords: Sigma factor; Sigma

During sporulation of the Gram-positive bacterium Bacillus subtilis, transcription genes encoding spore coat proteins in mother-cell compartment sporangium is controlled by RNA polymerase containing sigma subunit called K. Based on comparison N-terminal amino acid sequence K with nucleotide gene (sigK), primary product sigK was inferred to be a pro-protein (pro-sigma K) 20 extra acids at N terminus. Using antibodies generated against pro-sigma K, we have detected beginning third hour and about 1 hr later. Even when expressed artificially during growth throughout sporulation, appears normal time expression K-controlled occurs normally. These results suggest that an inactive precursor proteolytically processed active developmentally regulated fashion. Mutations block forespore accumulation but not suggesting processing regulatory device couples programs two compartments sporangium. We propose this ensures completion morphogenesis prior synthesis will encase forespore.