Assessment of alkaline cholesterol oxidase purified from Rhodococcus sp. PKPD-CL for its halo tolerance, detergent and organic solvent stability

摘要: The novel bacterium, Rhodococcus sp. PKPD-CL was isolated and identified from the 'Chilika Lake' located at Odisha state of India, which is a largest brackish water habitat in Asia. produces extracellular halo tolerant, detergent organic solvent stable alkaline cholesterol oxidase. It has apparent molecular weight 60 kDa purified 59 fold by using 60% saturated ammonium sulfate fractionation, anion exchange followed size exclusion chromatographic techniques with 37% recovery. showed substrate specificity for 3β-hydroxysteroids Km 1.1 × 10(-4)M cholesterol. pH, 8.0 temperature, 37 °C were required its optimum activity. Enzyme considerably pH 6.0-8.5 temperature up to 50 °C. At 4 30 it maintained 100% activity days. isoelectric point enzyme 9.5. 80% residual 20% NaCl (3.42 M) 83% relative 12% (2.05 concentration. metal ions like Zn(2+), Cu(2+), Ag+, Fe(3+), Ba(2+) inhibited >60% while Hg(2+) served potent inhibitor whereas Mg(2+) found be good enhancer it. presence chemical reagents (NaN3, EDTA), detergents (Tween-80, Tween-20, Triton X-100, sodium cholate) various solvents (isopropanol, ethanol, benzene, chloroform, methanol, toluene, ethyl acetate, butanol dimethylsulfoxide). Such multi stress tolerant versatile produced may serve as choice industrial applications.