 BackResearch Article ScienceAsia 10 (1984): 043-051 |doi: 10.2306/scienceasia1513-1874.1984.10.043
PROPERTIES OF A PARTIALLY - PURIFIED ESTERASE FROM ASPERGILLUS NIGER NRRL 337
MOLSIRI VEEROTHAIABSTRACT: An esterase has been isolated from an aqueous extract of a wheat bran culture of Aspergillus niger NRRL 337 by ammonium sulfate precipitation, followed by chromatography on DEAE Sephadex A-50, Sephadex G - 100, DEAE Sepharose and Sephadex G - 75. The partially purified enzyme had a specific activity (methyl acetyl salicylate, MAS, as a substrate) of 30.4 units per mg of protein. The apparent Km for MAS was 7.5 mM. The molecular weight was estimated as about 100,000 by gel filtration and as 120,000 by HPLC. The enzyme catalyzed the preferential hydrolysis of esters derived from short chain fatty acids. A serine residue may participate in the catalysis of hydrolysis by the enzyme. Other molecular characteristics of the enzyme are described. Department of Home Economics, Faculty of Science, Srinakarinwirot University (Prasanmitr), Bangkok 10110, Thailand. Received 15 September 1983
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