Cleavage Specificities and Synergistic Catalytic Action of Brevibacillus gelatini -Derived Thermostable Keratinolytic Protease BrgM4 and Reductase BrgTrxR on Feather Keratin

are important for BrgM4-substrate binding. These findings provide insights into the BrgM4 function and synergistic catalytic activity of keratinolytic protease and reductase, guiding the design of enzyme cocktails for efficient keratin conversion.