Cellulase physical properties

Two Pea Cellulases Display the Same Catalytic Mechanism Despite Major Differences in Physical Properties... 

Physical Properties. All of the cellulase (CMCase) activity which develops in auxin-treated pea apices dissolves in salt solutions (e.g., phosphate buffer, 20mM, pH 6.2, containing 1M NaCl). Gel chromatography of such extracts indicates the presence of two cellulase components with similar levels of activity and elution volumes corresponding to molecular weights of about 20,000 and 70,000 (Figure 1). If the tissue is extracted with buffer alone, only the smaller cellulase dissolves (referred to as buffer-soluble or BS cellulase). The larger buffer-insoluble (BI) cellulase can then be extracted from the residue by salt solutions. This simple extraction procedure effectively separates the two cellulases, and can be used as an initial step for their estimation or purification. 

Parameters to describe a solid-state fermentation process for cellulase production include physical properties such as temperature, pH, humidity and water activity, particle size, pile and real densities, pore size and porosity, etc. chemical components such as medium composition, gas-phase composition, amount and properties of microorganisms, activities of cellulases, etc. and kinetic para-... 

Purification and Physical and Chemical Properties. Extracellular cellulase components A and B and cell-bound cellulase component C were purified through the steps summarized in Figure 7 from the cultures of Ps. fluorescens on 0.5% Avicel and on 0.5% cellobiose, respectively. The purified cellulase components (Cellulases A, B, and C) thus obtained showed a single peak in zone electrophoresis on cellulose acetate film and starch bed. 

Discrimination of Cellulase Components A, B, and C. The physical and chemical properties as well as substrate specificities of the highly purified cellulases of Ps. fluorescens have been characterized and are summarized in Table IV. Cellulase A is different from Cellulase B in the mobility on zone electrophoresis and in the pattern of Sephadex G-25 chromatography, but similar in substrate specificity toward several reduced and nonreduced cello-oligosaccharides. On the other hand, Cellulase C is different from A in the pattern of DEAE-Sephadex chromatography and the substrate specificity, and from B in all respects. These characteristics of each cellulase component are therefore different enough to be used as criteria to discriminate one from the other. 

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