Abstract:

The recombinant pectinase expressed in Escherichia coli BL21/pET-pel was purified by ultrasonic cell disruption
and nickel ion affinity chromatography, and detected using SDS-PAGE. Its enzymatic characteristics were analyzed. The
results showed that purification fold of the recombinant pectinase was 1.71, and recovery was 88.5%. Molecular weight
of the recombinant pectinase was approximately 44 kD. Its optimal temperature and pH were 45–55 ℃ and 9.0–9.5. It
was stable at pH 7.0–10.0. When the recombinant pectinase was incubated for 30 min at 60 ℃, the relative activity was
approximately 40%. Different metal ions revealed different effects on the recombinant pectinase, which was activated by
Ca2+ and Co2+ but inhibited by Fe2+.

Key words: recombinant pectinase, intracellular enzyme, nickel ion affinity chromatography, enzymatic characteristic