Characteristics of Enzymes Produced by Ruminococcus flavefaciens which Degrade Plant Cell Walls

Abstract

Summary: Enzyme preparations active against crystalline cellulose, marble-milled filter paper, carboxymethyicellulose (CM-cellulose), hemicellulose and xylan were obtained from cultures of Ruminococcus flavefaciens. These preparations also contained swelling factor, pectin methylesterase, pectin lyase and low levels of aryl β-glucosidase and aryl β-xylosidase. CM-cellulase and xylanase activities were present in a high molecular weight complex, but substrate competition studies showed that different active sites were probably responsible for each activity. Analysis of products and viscosity changes during enzymic hydrolysis of CM-cellulose and xylan indicated that the most active enzymes were of the exo-1, 4-β-glycosidase type. A variety of reducing sugars were released from cell walls of Lolium perenne (perennial ryegrass) by enzyme preparations.