Peculiarities of the biosynthesis of Bacillus intermedius glutamyl endopeptidase in recombinant Bacillus subtilis cells during the stationary growth phase

Abstract

We studied the biosynthesis of Bacillus intermedius glutamyl endopeptidase in the recombinant Bacillus subtilis strain AJ73 Δ58.21 during the stationary growth phase. We optimized the composition of the culture medium to favor effective enzyme production during the stationary growth phase, and found that the nutritional requirements for glutamyl endopeptidase synthesis were different in the stationary phase and growth retardation phase. Proteinase accumulation was activated by complex organic substrates (casein and gelatin). During final stages of the culture growth, the enzyme production was stimulated by Ca2+, Mn2+, and Co2+ and inhibited by Zn2+, Fe2+, and Cu2+. The synthesis of glutamyl endopeptidase in the late stationary phase was not inhibited by glucose, unlike that in the trophophase during proliferation. We conclude that the regulatory mechanisms of proteinase synthesis during vegetative growth and sporulation are different.