| abstract |
FIELD: enzymology, protein engineering, in particular enzyme with proteolysis activity. n SUBSTANCE: invention relates to new subtilisin variants obtained by substitution in amino acid sequence of wild-type enzyme following by certain charge alteration in corresponding site, namely negative charge increasing (positive charge decreasing) or vice versa. Subtilisin variants with the first-type substitutions have higher cleaning activities mainly in systems with law detergent concentrations. Subtilisin variants with the second-type substitutions have higher cleaning activities mainly in systems with high detergent concentrations. Variants being effective both in systems with low and high detergent concentration also are disclosed. New subtilisin variants are obtained by expression of DNA mutant sequence in cells of strain Bacillus. Subtilisin muteins of present invention are useful in cleaning compositions and composition for cloth treatment, as well as in animal feed additives. n EFFECT: enzyme of improved effectiveness. n 18 cl, 4 dwg, 14 tbl, 2 ex |