Preparation and characterization of alpha-D-glucopyranosyl-alpha-acarviosinyl-D-glucopyranose, a novel inhibitor specific for maltose-producing amylase.
A novel inhibitor against maltose-producing alpha-amylase was prepared via stepwise degradation of a high-molecular-weight acarbose (HMWA) using Thermus maltogenic amylase (ThMA). The structure of the purified inhibitor was determined to be alpha-D-glucopyranosyl-alpha-acarviosinyl-D-glucopyranose (GlcAcvGlc) by (13)C NMR and MALDI-TOF/MS. Progress curves of PNPG2 hydrolysis by various amylolytic enzymes, including MGase, ThMA, and CDase I-5, in the presence of acarbose or GlcAcvGlc indicated a slow-binding mode of inhibition. Analytical ultracentrifugation and X-ray crystallography analyses revealed that the presence of GlcAcvGlc increased the dimerization of ThMA. The formation of dimer complexed with GlcAcvGlc might induce a conformational change in ThMA, leading to a two-step inhibition process. The inhibition potency of GlcAcvGlc for MGase, ThMA, and CDase I-5 was 3 orders of magnitude higher than that of acarbose.
Kim
Myo-Jeong
MJ
Research Center for New Bio-Materials in Agriculture and Department of Food Science & Technology, School of Agricultural Biotechnology, Seoul National University, Suwon 441-744, Korea.
Lee
Hee-Seob
HS
Cho
Jin-Sook
JS
Kim
Tae-Jip
TJ
Moon
Tae-Wha
TW
Oh
Sang-Taek
ST
Kim
Jung-Wan
JW
Oh
Byung-Ha
BH
Park
Kwan-Hwa
KH
D020909:Acarbose / Q000494:pharmacology; D000681:Amylases / Q000037:antagonists & inhibitors*; D002240:Carbohydrate Sequence; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D008320:Maltose / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000037:antagonists & inhibitors* / Q000737:chemistry
D004791:Enzyme Inhibitors; D009844:Oligosaccharides; C462531:glucopyranosyl-acarviosinyl-glucopyranose; D008320:Maltose; D000681:Amylases; D020909:Acarbose