Synthesis of maltotriose by maltase purified from rabbit kidney.
To clarify the enzyme participates in maltotriose synthesis, we purified maltase from rabbit kidney using 2-amino-2-hydroxymethylpropane-1,3-diol (Tris) affinity column chromatography. The purified enzyme possessed specific activity of 33.7 mumol/mg/min and estimated molecular weight of 350,000 dalton, as judged by SDS-polyacrylamide gel electrophoresis, comparable with those reported from rat kidney. Moreover this enzyme possessed not only maltase (maltose----glucose) but also amylomaltase (maltose----maltotriose) activity, and both activities were inhibited by Tris in a dose-dependent manner with similar IC50 values. From these results, we concluded that maltotriose was synthesized by maltase in vitro and that kidney maltase may participate in sugar metabolism in vivo.
Itoh
K
K
Department of Molecular Cardiology, Center for Adult Diseases, Osaka, Japan.
Hara
T
T
Shibata
N
N
D000818:Animals; D002845:Chromatography; D004591:Electrophoresis, Polyacrylamide Gel; D007668:Kidney / Q000201:enzymology*; D008970:Molecular Weight; D011817:Rabbits; D014312:Trisaccharides / Q000096:biosynthesis*; D000520:alpha-Glucosidases / Q000302:isolation & purification / Q000378:metabolism*
D014312:Trisaccharides; C008317:maltotriose; D000520:alpha-Glucosidases