IDENTIFICATION AND CHARACTERIZATION OF SPORULATION GENE SPOVS FROM BACILLUS-SUBTILIS

We report the identification and characterization of an additional spo rulation gene from Bacillus subtilis called spoVS, which is induced ea rly in sporulation under the control of sigma(H). We show that spoVS i s an 86-codon-long open reading frame and is capable of encoding a pro tein of 8,796 Da which exhibits little similarity to other proteins in the databases. Null mutations in spoVS have two contrasting phenotype s. In otherwise wild-type cells they block sporulation at stage V, imp airing the development of heat resistance and coat assembly. However, the presence of a spoVS mutation in a spoIIB spoVG double mutant (whic h is blocked at the stage [II] of polar septation) acts as a partial s uppressor, allowing sporulation to advance to a late stage. The implic ations of the contrasting phenotypes are discussed in the context of t he formation and maturation of the polar septum.