Bacillus subtilis spore coats: complexity and purification of a unique polypeptide component
UMass Chan Affiliations
Department of Microbiology and Physiological SystemsDepartment of Microbiology
Document Type
Journal ArticlePublication Date
1978-09-01Keywords
Bacillus subtilisspore
protein
Bacteriology
Biochemistry, Biophysics, and Structural Biology
Physiology
Metadata
Show full item recordAbstract
Extensively washed, dormant spores of Bacillus subtilis were disrupted with glass beads in buffer at pH 7 in the presence of protease inhibitors. Approximately 31% of the total spore protein was soluble, and another 14% was removed from the insoluble fraction by hydrolysis with lysozyme and washing with 1 M KCl and 0.1% sodium dodecyl sulfate. The residual spore integuments comprised 55% of the total spore proteins and consisted of coats and residual membrane components. Treatment of integuments with sodium dodecyl sulfate and reducing agents at pH 10 solubilized 40% of the total spore protein. Seven low-molecular-weight polypeptide components of this solubilized fraction comprised 27% of the total spore protein. They are not normal membrane components and reassociated to form fibrillar structures resembling spore coat fragments. The residual insoluble material (15% of the total spore protein) was rich in cysteine and was probably also derived from the spore coats. A solubilized coat polypeptide of molecular weight 12,200 has been purified in good yield (4 to 5% of the total spore protein). Five amino acids account for 92% of its total amino acid residues: glycine, 19%; tyrosine, 31%; proline, 23%; arginine, 13%; and phenylalanine, 6%.Source
J Bacteriol. 1978 Sep;135(3):1091-106. Link to article on publisher's website