Occurrence of a thermoacidophilic cell-bound exo-pectinase inAlicyclobacillus acidocaldarius

Alicyclobacillus acidocaldarius was able to degrade pectin under thermoacidophilic conditions of high temperature and acidity. Both extracellular and cell-bound pectolytic activities were found (28 and 72% of total activity, respectively). WhenA. acidocaldarius was subjected to lysozyme or sonication, more than 50% of the activity was found to be bound with the cell debris. The cell-bound enzyme presented principally exopectolytic activity. SDS-PAGE and zymogram showed that the estimated molar mass of the crude enzyme was 52 kDa. pH optimum was between 1.5 and 2.0 and the enzyme was thermostable at 70°C for 1 h at pH 2.0.