Purification and Biosynthesis of a Spore Coat Protein in Bacillus megaterium QM B1551

Summary: A spore coat protein of Bacillus megaterium QM B1551 was purified from an SDS-DTT extract of lysozyme-digested spores using Sephadex, DEAE-cellulose chromatography and polyacrylamide disc gel electrophoresis. The molecular weight of the protein was approximately 12000. It constituted about 13% of spore dry weight and was rich in lysine, aspartic acid, glycine and alanine residues. The sum of these four amino acids constituted 53.9% of the total amino acids. Small amounts of phosphorus and sugar were detected, but no amino sugar. The protein was synthesized in the cytosol of sporulating mother cells at t 3, and accumulated on the forespores.