Abstract
L-asparaginase is a vital antineoplastic drug. The side effects of the current formulations intrigued researchers to explore novel candidates. The study evaluated a novel type-II L-asparaginase from Chryseomicrobium amylolyticum from marine crab, Scylla serrata. Statistical optimization enhanced production to 281.6 from 115.69 IU/ml. The purified enzyme had 173.69 IU/mg protein specific activity. The Km, Vmax, and Kcat were 6.364 µM, 909.09 µM/min, and 222.82 /sec. The enzyme didn't react with L-glutamine, D-glutamine, L-glutamic acid, and urea, a clinically desirable feature. In vitro trypsin and serum half-life were ~ 39 h and ~ 27 min. The study enlisted ions, protein-modifying agents, and surfactants influencing its activity. The detailed in silico analyses of the functional gene predicted its physicochemical and structural features. The low sequence identity with the commercial enzymes and the predicted nonallergenic and nontoxic features suggested its clinical suitability. Molecular docking revealed a higher binding affinity for L-asparagine than L-glutamine and urea. The IC50 against MCF7, MOLT4 and THP-1 cell lines were 0.043, 0.041, and 0.05 IU/ml, respectively. Phase contrast microscopy confirmed its cytotoxicity. Flow cytometry demonstrated 81.4% apoptotic cells in MOLT-4 cells at IC50, signifying potent anticancer activity. The enzyme did not affect normal human fibroblast cells and was non-haemolytic. The results underscore the therapeutic potential of C. amylolyticum type-II L-asparaginase and support further in vivo studies to advance L-asparaginase-based cancer therapies.