Genomic insights and Taguchi-based optimization of culture conditions for enhanced alkaline protease production in Streptomyces barkulensis RC1831

This study presents a genome analysis identifying various alkaline protease genes and culture condition optimization to enhance the production of the enzyme in Streptomyces barkulensis RC1831. The analysis of genes using bioinformatics tools such as RAST, KEGG, KAAS, and BLASTx revealed the presence of 10 genes that are responsible for alkaline protease production belonging to different families. Multiple sequence alignment showed a high sequence identity with M24 family serine protease followed by subtilisin-like serine protease. Optimal conditions for enhanced protease production were determined to be at 37°C, pH 11, casein1 % (W/V), dextrose 0.5 % (W/V), urea 0.5 % (W/V), tryptophan 1 % (W/V), 1 mM Mn +2 , 1 % (V/V) Tween-80 in LB medium and an incubation time of 72 hours. Out of the 10 alkaline protease genes, 2 genes expressed significantly according to the activity observed during optimization processes i.e., M24 family, Mn +2 dependent metalloprotease and subtilisin-like serine, ca +2 dependent metalloprotease. Furthermore, the AP enzyme was remarkably stable in the presence of various cofactors (Metal ions) and surfactants, indicating its potential for industrial applications under diverse conditions. • Optimal enzyme production conditions from strain RC1831 include 37°C, pH 11, specific concentrations of casein, dextrose, urea, tryptophan, Mn 2+ , and Tween-80 in LB medium, and a 72-hour incubation. • Genome mining using tools like RAST, KEGG, KAAS, and BLASTx identified 11 genes linked to alkaline protease production. • The two highly expressed enzymes are a Mn 2+ dependent M24 family metalloprotease and a Ca 2+ dependent S8 family Subtilisin-like serine metalloprotease. • The alkaline protease enzyme demonstrated significant stability with various metal ions and surfactants, highlighting its industrial applicability.