In-silico mutagenesis of L- asparaginase enzyme derived from three microbiome strains: Potential implications for cancer treatment

Abstract

With possible ramifications for cancer treatment, this work examined how silico mutagenesis affected the L-asparaginase L-(ASNase) enzymes from three microbial sources: Bifidobacterium longum, Lactococcus lactis subsp. lactis, and Escherichia coli K12. The influence of mutagenesis on the binding affinity of L-asparagine was assessed by substituting a single amino acid at predicted active site residues using computational techniques such as molecular docking, active site prediction, and 3D protein modeling. Four distinct mutations of L-ASNase in E. coli (GLY198CYS, GLY198LEU, LEU190LYS, and PRO194ALA) showed a marginally higher binding affinity (-5.9 kcal/mol) than the wild-type enzyme (-5.8 kcal/mol). The 290–298 region was where L. lactis mutations exhibited clustering effects, with position 295 (ASN295) exhibiting mutational sensitivity. It's interesting to note that B. longum L-ASNase showed consistent binding reduction across all studied mutations (-5.8 kcal/mol versus wild-type -5.6 kcal/mol), indicating that its active site residues have evolved to be more efficient. Enzyme-substrate interactions are influenced by changes in charge distribution, steric effects, hydrogen bonding capacities, hydrophobicity, and secondary structure integrity, according to a thorough examination of these mutations. Even though there were only slight changes in binding energy, our research offers important new information on the structure-function relationship of L-ASNase enzymes and suggests possible targets for enzyme engineering to improve therapeutic efficacy in cancer treatment applications.