PECTINOLYTIC ENZYMES OF ANAEROBIC FUNGI

Pectinolytic enzymes of four rumen fungi have been described. Three fu ngal species were monocentric Neocallimastix spp. H15, JL3 and OC2, an d one isolate was a polycentric strain of Orpinomyces joyonii, A4. The y differed in degree of pectin degradation and utilization. Only the s train Neocallimastix sp. H15 and partially Orpinomyces joyonii A4 were able to utilize pectin to a higher extent. The most important pectino lytic activity in all these isolates represented pectin lyase (EC 4.2. 2.10) and polygalacturonase (EC 3.2.1.15). Their specific activities w ere in the range of 10-900 and 10-450 mu g galacturonic acid h(-1) mg protein(-1) for pectin lyase and polygalacturonase, respectively. Poly galacturonase, located mainly in the endocellular fraction, was inhibi ted by calcium ions and had the main pH optimum at pH 6.0. All strains produced pectate lyase (EC 4.2.2.2). None of the strains tested produ ced pectinesterase (EC 3.1.1.11).