Purification and characterization of protopectinase produced by Kluyveromyces marxianus

الملخص EN

The crude protopectinase preparation obtained from Kluyveromyces marxianus cultures was partially purified by fractional precipitation with ammonium sulphate.

At 65 % ammonium sulphate, the most active fractionation was obtained.

Further purification by gel filtration on CM-Sephadix C-50 followed by ion exchange chromatography on Sephadix G-75 yielded 4 peaks of protopectinase components.

The second peak was the major one containing most of the recovered protein and all the protopectinase activity.

The enzyme showed different hydrolytic activities on some protopectin sources.

Characterization of the enzyme including, enzyme concentration, amount of substrate, pH and temperature of the reaction mixture was carried out.

The enzyme was stable up to 50ºC and at pH range between 4 and 7.

The enzyme activity was responded differently to the tested metal ions and some inhibitors.

The amino acids composition of the enzyme showed a high proportion of glycine and moderate amounts of glutamic acid, alanine and leucine but poor contents of proline, cysteine and tyrosine.