Purification and Properties of Extracellular and Cell-bound Cellulase Components of Pseudomonas fluorescens var. cellulosa

Publisher Website
Google Scholar
Abstract
Two extracellular (A and B) and one cell-bound (C) cellulase [EC 3.2.1.4] components of Pseudomonas fluorascens var.. cellulosa were purified. Each of them showed practically a single peak upon ultracentrifugation and electrophoresis and was free from cellobiase and p-nitropheny1 β-glucosidase as well as amylase. The contents of acidic amino acids in these cellulases were similarly higher than those of basic ones. They contained a considerable amount of carbohydrates. Galactose and glucose were the major constituent sugars, and glucosamine was detected in both cellulases A and B while galactosamine was detected in cellulase C. The cellulases hydrolyzed a variety of substances including cellooligosaccharides, amorphous and crystalline celluloses, and showed each characteristic hydrolysis pattern. They also hydrolyzed carboxymethyl cellulose in different rates and its hydrolysis by cellulase B was the slowest, whereas the mode of their action toward this substrate was similar in randomness. The hydrolysis rates of each bond of ordinary and reduced cellooligosaccharides by these cellulases were also characteristic of each cellulase. Only cellulase C attacked cellotriose beside higher cellooligosaccharides. Cellobiose was the main product from the latter. In contrast, cellulases A and B hydrolyzed cellooligosaccharides higher than cellotetraose and produced mainly cellobiose and cellotriose, in particular more cellotriose from ordinary and reduced cellohexaoses.

This publication has 0 references indexed in Scilit: