EXTRACTION AND PARTIAL PURIFICATION OF PROTEASE FROM LOCAL SERRATIA MARCESCENS

Abstract

ABSTRACTSerratia marcescens isolated from a patient with urinary tract infection taken fromthe Central Health Laboratory. The sensitivity test showed the resistant to theTetracyclin (30μg), Amoxicillin (25 μg), Gentamycin(30 μg), ampicillin (10μg), andKanamycin (30μg), but it was sensitive to Ciprofloxacin (5 μg) only. The extracellularprotease was extracted in LB broth and purified in two step included precipitationwith (30-55%) saturation of ammonium sulfate, dialysis and ion exchangechromatography by DEAE–Cellulose. Only one peak contained the enzymatic activity,and purification fold was 22.6 with 37.92% recovery. Based on the inhibitory effectsof EDTA, the protease was characterized as a metalloproteinase. The enzyme activitywas increased in the presence of Mg2+ and decreased in the presence of Cu2+ andZn2+. The protease could also be activated by the non-ionic surfactants Tween 80(1.0%) and Triton X-100 (1.0%).