Accumulation of an artificial cell wall-binding lipase by Bacillus subtilis wprA and/or sigD mutants

A recombinant lipase, CWB-LipB, localized on the Bacillus subtilis cell sur face and retaining lipase activity was unstable and not accumulated in a hi gh yield. To improve the accumulation, we examined cell wall binding protea se (wprA)- and/or sigma D (sigD)-deficient mutants, and also a NprE and Apr A protease-deficient mutant as host strains. The nprE aprA mutation did not lead to a significant increase in the CWB-LipB accumulation. The wprA muta nt accumulated a greater amount than the wild-type only in the stationary p hase, but the sigD mutant accumulated a greater amount in both the exponent ial and stationary phases. The double mutant exhibited great accumulation o f CWB-LipB, the amount being 36% of the total proteins extracted from the c ell surface. (C) 2000 Federation of European Microbiological Societies. Pub lished by Elsevier Science B.V. All rights reserved.