72] Cellulose synthetase from plants

Abstract

Publisher Summary This chapter discusses the synthesis of cellulose synthetase from plants. The synthesis of cellulose in plants from α-D-glucose 1-phosphate appears to involve at least two distinct reactions. In the first, the nucleotide guanosine diphosphate D-glucose (GDP-D-glucose) is formed by a pyrophosphorylase from guanosine triphosphate and α-D-glucose 1-phosphate. The polysaccharide is then formed by another enzyme(s) referred to as a “transferase,” which catalyzes the repetitive D-glucosyl transfer to an acceptor. Although GDP is formed in the reaction, it is not identified. The acceptor, which is present in the particles along with the transferase, is not characterized. The assay is based on the insolubility of cellulose in water and in hot alkali. The reagents used, procedure followed, and the properties of the enzyme are also described in the chapter. The cellulose synthesizing system shows a complete specificity for GDP-D-glucose. The synthesis of cellulose from GDP-D-glucose is also catalyzed by particulate enzyme preparations from etiolated seedlings of string bean, squash, pea, and corn.