3256-04-0Relevant articles and documents
Purification and characterization of 1,3-β-D-glucan phosphorylase from Ochromonas danica
Yamamoto, Yutaka,Kawashima, Daichi,Hashizume, Ayu,Hisamatsu, Makoto,Isono, Naoto
, p. 1949 - 1954 (2013/10/08)
1,3-β-D-Glucan phosphorylase (BGP) is an enzyme that catalyzes the reversible phosphorolysis of 1,3-β- glucosidic linkages to form α-D-glucose 1-phosphate (G1P). Here we report on the purification and characterization of BGP from Ochromonas danica (OdBGP). The purified enzyme preparation showed three bands (113, 118, and 124 kDa) on SDS-polyacrylamide gel electrophoresis. The optimum pH and temperature were 5.5 and 25°C-30°C. OdBGP phosphorolysed laminaritriose, larger laminarioligosaccharides, and laminarin, but not laminaribiose. In the synthesis reaction, laminarin and laminarioligosaccharides served as good acceptors, but OdBGP did not act on glucose. Kinetic analysis indicated that the phosphorolysis reaction of OdBGP follows a sequential Bi Bi mechanism. The equilibrium of the enzymatic reaction indicated that OdBGP favors the reaction in the synthetic direction. Overnight incubation of OdBGP with laminaribiose and G1P resulted in the formation of precipitates, which were probably 1,3-β-glucans.
Characterization of a bacterial laminaribiose phosphorylase
Kitaoka, Motomitsu,Matsuoka, Yasuyuki,Mori, Kiyotaka,Nishimoto, Mamoru,Hayashi, Kiyoshi
, p. 343 - 348 (2012/08/08)
Bacterial laminaribiose phosphorylase (LBPbac) was first identified and purified from cell-free extract of Paenibacillus sp. YM-1. It phosphorolyzed laminaribiose into α-glucose 1-phosphate and glucose, but did not phosphorolyze other glucobioses. It slightly phosphorolyzed laminaritriose and higher laminarioligosaccharides. The specificity of the degree of polymerization of the substrate was clearly different from that of the enzyme of Euglena gracilis (LBPEug): LBPbac was more specific to laminaribiose than LBPEug. It showed acceptor specificity in reverse phosphorolysis similar to LBPEug. Cloning of the gene encoding LBPbac (lbpA) has revealed that LBPbac is a member of the glucoside hydrolase family 94, which includes cellobiose phosphorylase, cellodextrin phosphorylase, and N,N0-diacetylchitobiose phosphorylase. The genes that encode the components of an ATP-binding cassette sugar transporter specific to laminarioligosaccharides were identified upstream of lbpA, suggesting that the role of LBPbac is to utilize laminaribiose generated outside the cell. This role is different from that of LBPEug, which participates in the utilization of paramylon, the intracellular storage 1,3-β-glucan.
