Biomaterial Database

Discrimination of porcine glycogen debranching enzyme isozymes by the ratios of their 4-alpha-glucanotransferase and amylo-alpha-1,6-glucosidase activities. 2010

Seiko Doi, and Yasushi Makino, and Kaoru Omichi

Department of Chemistry, Graduate School of Science, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.

Glycogen debranching enzyme (GDE) is a single-chain protein containing distinct active sites that exhibit 4-alpha-glucanotransferase and amylo-alpha-1,6-glucosidase activities. The ratios of these two activities in porcine liver and muscle GDEs were compared using a set of homologous fluorogenic branched dextrins. For quantifying 4-alpha-glucanotransferase activity, 6(3)-O-alpha-maltotetraosyl-PA-maltooctaose (B3/84), 6(4)-O-alpha-maltotetraosyl-PA-maltooctaose (B4/84), 6(5)-O-alpha-maltotetraosyl-PA-maltooctaose (B5/84) and 6(6)-O-alpha-maltotetraosyl-PA-maltooctaose (B6/84) were used as substrates and maltohexaose (G6) as the acceptor. The substrate for amylo-alpha-1,6-glucosidase activity was 6(3)-O-alpha-glucosyl-PA-maltotetraose (B3/41). HPLC analysis of the fluorogenic branched dextrin digests in the presence of G6 revealed that GDE 4-alpha-glucanotransferases produce the corresponding 6-O-alpha-glucosyl-PA-maltooctaose (GG8PA) and maltononaose (G9). The ratios of the 4-alpha-glucanotransferase activity to amylo-alpha-1,6-glucosidase activity, for the liver and muscle enzymes were respectively 0.240 and 0.0840 for B3/84, 0.204 and 0.0788 for B4/84, 0.145 and 0.0592 for B5/84, and 0.109 and 0.0458 for B6/84. These data clearly indicate that porcine liver and muscle GDEs are different from each other. The ratios of porcine brain GDE were 0.155, 0.131, 0.0990 and 0.0745 for B3/84, B4/84, B5/84 and B6/84, respectively. These results indicate that porcine brain GDE is also unique from liver and muscle enzymes, suggesting that it is either a third enzyme, or a mixture of 45% liver and 55% muscle GDEs.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D009844	Oligosaccharides	Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.	Oligosaccharide
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002851	Chromatography, High Pressure Liquid	Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.	Chromatography, High Performance Liquid,Chromatography, High Speed Liquid,Chromatography, Liquid, High Pressure,HPLC,High Performance Liquid Chromatography,High-Performance Liquid Chromatography,UPLC,Ultra Performance Liquid Chromatography,Chromatography, High-Performance Liquid,High-Performance Liquid Chromatographies,Liquid Chromatography, High-Performance
D003912	Dextrins	A group of low-molecular-weight carbohydrates produced by the hydrolysis of STARCH or GLYCOGEN. They are mixtures of polymers of D-glucose units linked by alpha-(1->4) or alpha-(1->6) glycosidic bonds.	Dextrin
D006004	Glycogen Debranching Enzyme System	1,4-alpha-D-Glucan-1,4-alpha-D-glucan 4-alpha-D-glucosyltransferase/dextrin 6 alpha-D-glucanohydrolase. An enzyme system having both 4-alpha-glucanotransferase (EC 2.4.1.25) and amylo-1,6-glucosidase (EC 3.2.1.33) activities. As a transferase it transfers a segment of a 1,4-alpha-D-glucan to a new 4-position in an acceptor, which may be glucose or another 1,4-alpha-D-glucan. As a glucosidase it catalyzes the endohydrolysis of 1,6-alpha-D-glucoside linkages at points of branching in chains of 1,4-linked alpha-D-glucose residues. Amylo-1,6-glucosidase activity is deficient in glycogen storage disease type III.	Glycogen Debranching Enzyme,Transfer-Glucosidase,Debranching Enzyme, Glycogen,Enzyme, Glycogen Debranching,Transfer Glucosidase
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013552	Swine	Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).	Phacochoerus,Pigs,Suidae,Warthogs,Wart Hogs,Hog, Wart,Hogs, Wart,Wart Hog