Unveiling the anticancer potential of L-Asparaginase (ASNase) from novel Streptomyces isolate HB2AG: Purification and characterization study

Abstract

L-asparaginase (ASNase) obtained from microbial origins is a significant enzyme in the commercial sphere, crucial for the treatment of acute lymphoblastic leukemia. In the current investigation, we isolated ASNase through techniques involving ammonium sulfate precipitation and DEAE sepharose anion exchange column chromatography, revealing a molecular weight of 35 kDa. The enzyme exhibited its peak activity at pH 8 and 40°C, maintaining approximately 99% of its enzymatic effectiveness. The Michaelis constant (Km) and maximum velocity (Vmax) were determined to be 0.0021 M and 714.3 µM/min, respectively. ASNase was found to be non-toxic on HEK293 cells and selectively effective against breast cancer, hepatocellular carcinoma cells, colorectal adenocarcinoma cells, Human lung cancer cell line, Neck squamous cells, and Human head carcinoma cells. Hepatocellular carcinoma cells exhibited remarkable responsiveness to ASNase, displaying an IC50 of 23 µg/mL. This led to observable changes in nuclear morphology indicative of apoptosis, as evidenced by DAPI and Annexin V-FITC staining. ASNase also showed cell migration potential on HEK293 cells. Streptomyces HB2AG ASNase’s dynamic functioning across pH and temperature ranges, as well as its stability at 40°C and cytotoxic potential, make it a promising pharmaceutical candidate for various applications.