Mapping of mutations affecting synthesis of exocellular enzymes in Bacillus subtilis. Identity of the sacUh, amyB and pap mutations.

The sacUh, amyB and pap mutations are identical with respect to their pleiotropic phenotype and their genetic location. Strains bearing these mutations overproduce several exocellular enzymes: alpha amylase, lavansucrase and proteases, they are poorly or not at all transformable and most of them are devoid of flagella. These mutations are tightly linked to the sacU- mutations by transformation and therefore lie between the hisA1 and gtaB290 markers. It is possible that the sacUh, amyB and pap mutations on one hand and the sacU- mutations on the other are two different classes of alterations of the same regulatory gene controlling the synthesis of some exocellular enzymes and several other cellular functions. Furthermore an amy- mutation, leading to the lack of alpha-amylase activity, was mapped between the lin2 and aroI906 markers which are not linked to the sacU locus.