Biochemical changes occurring during sporulation in Bacillus species

Abstract

The second step, which involves the acylation of the enzyme and the concomitant liberation of pnitrophenol, is characterized by the rate constant k2= 3-15 sec.-'. The third step involves the liberation of acetate and reactivation of the enzyme; the rate of this reaction is defined by kI3 = 0-0254 sec.-'. 2. The rate constant k2 for the second step is, within experimental error, the same at pH 6-45 and pH 7*75; from this and other available evidence it is suggested that it involves the acetylation of the OH group of a serine residue in the enzyme. The third step has a pH dependence similar to that previously found for the overall rate of reactions catalysed by chymotrypsin, and it is suggested that it involves the imidazole group of a histidine residue ofthe enzyme. The work described in this paper was carried out during the tenure by one of the authors (J.M.S.) of a Fulbright Scholarship and a Guggenheim Fellowship. The other author (H. G.) is an Imperial Chemical Industries Research

Function and Location of a "Germination Enzyme" in Spores of Bacillus Cereus

“…3). Inosine, calcium and n-dodecylamine (a chemical germinant; Rode & Foster, 1960b), did not affect release during 5 min. at 4".…”

“…Within a dormant spore the enzyme clearly does not attack its substrate; however, on addition of the correct germinant the enzyme may act to cause rapid germination. The theory that germination involved depolymerization of spore mucopeptide by a lytic enzyme was originally proposed by Powell & Strange (1956). The purpose of the experiments described in this paper is to try to find whether activation, or release of the enzyme from a bound form does occur during germination.…”

“…It can also be simulated by what appear to be less natural means; i.e. by mechanical abrasion (Rode & Foster, 1960a), by surface active substances (Rode & Foster, 1960b), by alkanes (Rode & Foster, 1965), by enzymes like lysozyme (Gould & Hitchins, 1963), a spore enzyme (Gould & Hitchins, 1965) and by a heat-activated factor+a cofactor in Bacillus cereus strain T spore extracts (Vary, 1965). How a ' germinant ' initiates the normal germination reaction is unknown.…”

SEROLOGICAL STUDIES ON THE FORMATION OF PROTEIN PARASPORAL INCLUSIONS IN BACILLUS THURINGIENSIS

“…It is known that cells increase in dry weight during sporulation in suitable media (14) and that carbon and nitrogen compounds may be depleted from the medium (12). It is also probable that crystals are smaller and spores less resistant when cells are sporulated endotrophically.…”

Metabolism during the growth and sporulation of Bacillus cereus var mycoides

“…The sporulation of Bacillus sphaericus was stimulated by the addition of bi carbonate or alpha-ketoglutarate to the medium (Powell and Hunter, 1955). Powell and Strange (1956) observed the accumulation of alpha-ketoglutarate in a complex medium before the onset of sporulation in JB. cereus and B..…”