Optimization, purification and characterization of L-asparaginase from clinical Acinetobacter baumannii isolated from hospitals in Ramadi city-Iraq

Abstract

In the current study,32 isolates belonging to the bacteria Acinetobacter baumannii were isolated. It was diagnosed using several diagnostic methods, including microscopic, biochemical, culture and VITIK 2. Its ability to produce the L-asparaginase was also studied, and the optimal conditions for production were studied, where lactose was the best carbon source, casein the best nitrogen source, temperature 37, pH 8, and the incubation period was 24 hours, the best incubation period. The enzyme was also purified by ammonium sulfate precipitation, ion exchange chromatography, and gel filtration chromatography. High enzyme activity (0.85 Unit/ ml) and specific activity (4.25 U/mg. protein) were obtained in 70% ration saturation of ammonium sulphate After elution step in Gel filtration chromatography one peak was obtained and the activity of L-asparaginase was entirely associated with this peak. The L-asparaginase was purified from A. boumamanni using Sephadex G-150 as third step of purification with specific activity 13.7 U/ mg.