Effect of netropsin on the derepression of enzymes during growth and sporulation of Bacillus subtilis

Alkaline phosphatase production during sporulation of Bacillus cereus

Cell-bound alkaline phosphatase of Bacillus cereus was produced during vegetative growth and sporulation in a complex medium. Addition of glucose repressed the sporulation process and the amount of enzyme synthesized increased. The time course of alkaline phosphatase production is very similar in both sporulating and non-sporulating cells. Irrespective of sporulation, alkaline phosphatase level shows a peak of activity in the exponential phase, and another in the stationary phase of growth. This preliminary data indicates differences between B. cereus, and B. subtilis in alkaline phosphatase characteristics.

Studies on lipopeptide biosynthesis by Bacillus subtilis: isolation and characterization of iturin-, surfactin+ mutants

Two mutant strains, M35 and M89, were obtained by UV irradiation from a wild-type Bacillus subtilis producing iturin and surfactin. Sporulation and surfactin production were similar in both mutants and in the parent strain, while the iturin production of M35 was 300-fold less than that of the wild-type strain; M89 did not produce any iturin. The analysis of the incorporation of sodium [1-14C]acetate into cellular lipids and lipopeptides showed that M89 still synthesized beta-amino fatty acids, the lipid moiety of iturin.

Netropsin inhibits the increase of intracellular Ca(2+)-dependent serine proteinase activity in sporulating Bacillus megaterium

Netropsin suppressed the increase of intracellular proteolytic activity when added to B. megaterium incubated in a sporulation medium. The inhibited enzyme was a Ca(2+)-dependent serine proteinase. Sporulation and protein turnover in later sporulation phases were inhibited as well. Different concentrations of netropsin affected various aspects of protein catabolism differently.

An improved method for the purification of Bacillus subtilis glucose dehydrogenase cloned in Escherichia coli

An improved and simplified purification procedure has been developed for the isolation of the Bacillus subtilis glucose dehydrogenase which has resulted in a 10 fold higher yield of pure enzyme. The purification procedure utilizes gene cloning and an additional ammonium sulfate step to facilitate the removal of contaminating proteins. The procedure requires fewer chromatographic steps than previously reported, thus simplifying the procedure. This improved and simplified purification of B. subtilis glucose dehydrogenase will facilitate further structure-function studies of this sporulation specific enzyme.

Characterization and properties of an LL-oligopeptidase from sporulating cells of Bacillus sphaericus

An LL-oligopeptidase was characterized in the cell cytoplasm of sporulating Bacillus sphaericus 9602. Its activity showed a threefold increase throughout sporulation. The enzyme has lytic activity on various LL-dipeptides, especially on dipeptides with N-terminal L-alanine. Lytic activity was also found on some tripeptides and larger peptides which contain the sequence L-Ala-L-Ala. The role of this oligopeptidase in relation to sporulation may be to supply the cell with L-alanine for the biosynthesis of the peptide chains of the spore cortex.