Comparative L-Methioninase Activity, Anticancer Activity and Molecular Docking Studies of L-Methioninase from Microbial Isolates

Cancer is a major global health concern due to the high mortality rate associated with it. Only cancer cells exhibit methionine dependency, and cannot proliferate in a methionine-depleted environment. Hence, L-methionase has drawn considerable attention as a potential treatment for cancer. Based on this, the present study was aimed on the isolation and purification of L-Methioninase from microbes, and evaluation of its cytotoxic effects on liver cancer (HepG2) and cervical cancer (HeLa) cell lines. Different samples were collected for the isolation of microorganisms capable of producing L-methioninase. The enzymes from these were further purified by ammonium sulphate and acetone precipitations. The purified enzymes were treated on to HepG2 and HeLa cell lines and checked for cytotoxicity by MTT, LDH and trypan blue assays. The molecular docking of L-methioninase to methionine and homocysteine were assessed through AutoDock tools 1.5.7. Among the 21 isolates, 4 microbial isolates were shortlisted based on their L-methioninase activity. These 4 isolates were named as B4 and B6 (Bacteria), F6 (fungi), A2 (Actinomycete). The results were analyzed using Pymol. The purified L-methioninase from two isolates were having high methioninase activity and cytotoxicity and identified as Pseudomonas plecoglossicida JUB4 and Streptomyces cavourensis JUA2. L-methioninase from these isolates had promising anticancer properties, and hence show promise towards further purification, characterization, and anticancer applications.