nonhuman unclassified drug Western blotting amino acid sequence article Amino acid sequence Bacilli Bacillus subtilis Bacteriology C-terminal domains Cloning and expression Enzymatic activities Functional verification Hydrolase activities Hydrolases Lactobacillus acidophilus Salmonella Salmonella enterica amino acid bacterial enzyme bacterium bioassay carboxy terminal sequence enzyme activity enzyme analysis functional role gene expression hydrolase nucleotide sequence peptidoglycan hydrolase