Evaluation of in vitro Anti-proliferative Activity of L-arginine deiminase from Novel Marine Bacterial Isolate

L-Arginine deiminase is a therapeutic l-arginine depleter found to counteract various arginine auxotrophic cancer cells (do not express ASS/OCT). The aim of the present study was to evaluate the anti -proliferative activity of the purified l-arginine deiminase from Vibrio alginolyticus 1374. Production of the enzyme was carried out by shake flask method under optimal conditions. The enzyme thus produced was purified to near homogeneity by ammonium sulphate fractionation followed by ion exchange and gel filtration chromatography. The enzyme was purified to 529.43 fold and showed final specific activity of 280.6 IU/mg with 43.5% yield. SDS-PAGE revealed that the purified enzyme had a molecular weight of 48 kDa. The purified enzyme tested against A375-C6, MCF-7, HCT-113 and Jurkat, clone E6-1cell lines showed I.C.50 value of about 5. 21, 6.3,8 and 3.13 U/ml respectively. ADI obtained from Vibrio alginolyticus 1374 has several beneficial properties needed for its use as a therapeutic and industrial enzyme. It was active over wide range of pH (4-10) and temperature (25°-50°C), had high substrate specificity etc. Moreover it showed broad range of activity against cancer cells lines of human origin. Further animal model studies must be carried out to develop ADI as a potential drug.