Patent ID: 7371839

Claim:
An isolated polynucleotide encoding an alkaline protease having at least 95% homology to the amino acid sequence represented by SEQ ID NO:1, wherein one or more of (a) to (d) are met: (a) K84, or the position corresponding thereto, is replaced with R; (b) L104, or the position corresponding thereto, is replaced with P; (c) M256, or the position corresponding thereto, is replaced with an amino acid selected from the group consisting of A, S, Q, V, L, N, E, and D; and (d) D369, or the position corresponding thereto, is replaced with N, wherein said alkaline protease has oxidant resistance, is active at an alkaline pH, and retains at least 80% residual alkaline protease activity of the alkaline protease of SEQ ID NO: 1 when treated at pH 10 for 10 minutes.