Abstract: A mutated subtilisin suitable for admixture to washing compositions and exhibiting substantially improved stability over naturally occurring Bacillus serine proteases is prepared by expressing a modified gene encoding subtilisin in Bacillus subtilis. A preferred subtilisin analog product differs from wild-type Bacillus alkaline proteases by having any amino acid, and preferably serine, at position 218 in place of asparagine. The product is preferably produced in a strain of B. subtilis which is mutated to block synthesis of endogenous proteases. The method of replacing an Asn or a Gly in an Asn-Gly sequence in order to improve pH and thermal stability may be applied to other sites in subtilisin and to other proteins as well.

Abstract: A class of subtilisin analogs suitable for admixture to cleaning compositions and having improved stability over naturally occurring Bacillus subtilisins are prepared by expressing a modified gene encoding the subtilisin analog in Bacillus subtilis.

Abstract: This disclosure relates to a sucrose inducible expression system. The sucrose inducible expression system comprises a novel plasmid vector having a sacY gene of the sacS locus which binds to a transcription terminator to relieve transcription termination when introduced into a B. subtilis host microorganism.

Abstract: A class of subtilisin analogs suitable for admixture to cleaning compositions and having improved stability over naturally occurring Bacillus subtilisins are prepared by expressing a modified gene encoding the subtilisin analog in Bacillus subtilis. The subtilisin analogs are characterized as having a modified calcium binding site to improve calcium binding and either an Asn or a Gly replaced in any Asn-Gly sequences present in the subtilisin.