Popis: |
Two extracellular alkaline polygalacturonases from extracts of liquid cultures of Paenibacillus polymyxa 20185 were purified by gel filtration chromatography to homogeneity as judged by SDS-PAGE. The purified alkaline polygalacturonases (PG1 and PG2) had a similar molecular weight of 65 kDa, exhibited maximal activity at 50°C with pH 10.0, and were stable in alkaline conditions. The purified alkaline polygalacturonases activities were enhanced in the presence of Mg2+, and were resistant to inhibition by Mn2+, Zn2+and Cu2+. Michaelis-menten constants of PG1 and PG2 were found as 3.6mg/mL and 3.5mg/mL, respectively. |