PARTIAL PROPERTIES OF PECTIN METHYLESTERASE EXTRACTED FROM STREPTOMYCETE ISOLATE

Abstract

Pectinases are one of the upcoming enzymes of fruit and textile industries. We are here
reporting isolation and purification of pectin methyl esterase enzyme (PME) from an actinomycete
isolate (StET). This isolate was identified and appeared to be close to S. nigrifaciens. Although there
were some differences in the utilization of sucrose as sole carbon source for growth and producing
faint yellow pigment. PME was purified via gel permeation chromatography on Sephacryl S200
column equilibrated in 0.1 M sodium acetate buffer at pH 4.2. Purification process of PME produced
by Streptomyces sp. resulted in a pure protein preparation with specific activity of 1.70units/mg. A
specific band with a molecular weight of about 110 KDa having a high specific activity 1.9 units/mg
protein was obtained. PME was successfully purified by ammonium sulphate which increased the
specific activity of PME 0.22 to 1.70. Results revealed that the optimum temperature range of the
activity of purified PME was from 34 to 40˚C and the highest enzyme activity was recorded at pH
4.5. The effect of Zn+2, Fe+2, Mg+2, Co+2, Cu+2, Cd+2 and Mn+2 at 50 µg/ml on PME activity was also
determined.