Purification and characterization of esterase from marine <i style="">Vibrio fischeri</i> isolated from squid

Abstract

Bioluminescence bacterium <i style="">Vibrio fischeri</i> was produces esterase enzyme when the medium contained specific substrate. Esterase was purified from the culture supernatant. Most active fractions were obtained using the technique of precipitation with 1N HCl. Precipitated fraction was purified by ion exchange chromatography (DEAE-Cellulose) and gel filtration chromatography (Sephadex G200). Enzyme purity was determined by RP-HPLC. Purified active fraction exhibiting final specific activity of 300U/mg and characterized; the optimum <i style="">p</i>H was 7.5, the optimum temperature was 30°C. Enzyme was very stable at the temperature 30°C and at wide range of <i style="">p</i>H. Enzyme was monomeric protein having molecular mass of 37 kDa estimated by native PAGE assay.