1. Amylomaltase of Pyrobaculum aerophilum IM2 produces thermoreversible starch gels
- Author
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H.T.P. Bos, Thijs J. G. Ettema, Marc J. E. C. van der Maarel, Boguslawa Talik, Lubbert Dijkhuizen, Thijs Kaper, Groningen Biomolecular Sciences and Biotechnology, Bioproduct Engineering, Engineering and Technology Institute Groningen, Host-Microbe Interactions, Moleculaire Microbiologie, and TNO Kwaliteit van Leven
- Subjects
alpha-amylase family ,Hot Temperature ,Amylomaltase ,heat sensitivity ,POTATO D-ENZYME ,Microbiologie ,Food Industry ,CRYSTAL-STRUCTURE ,GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries) ,cysteine ,Potato starch ,large cyclic glucans ,Thermostability ,chemistry.chemical_classification ,potato d-enzyme ,glucan ,acarbose ,Binding mode ,Bioinformatics ,Microbiology ,Food technology ,hydroxyl group ,cyclodextrin-glycosyltransferase ,ALPHA-AMYLASE FAMILY ,Enzymology and Protein Engineering ,Glucan ,VLAG ,potato starch ,Glycogen Debranching Enzyme System ,LARGE CYCLIC GLUCANS ,Achaeal amylomaltase ,pyrobaculum aerophilum ,chemistry ,escherichia-coli ,Pyrobaculum ,archaeon thermococcus-litoralis ,Cellular energy metabolism [UMCN 5.3] ,Archean ,molecular cloning ,food industry ,Starch ,Cyclodextrin glycosyltransferase ,Applied Microbiology and Biotechnology ,chemistry.chemical_compound ,Enzyme Stability ,PYROCOCCUS-FURIOSUS ,Glycoside hydrolase ,glucose ,Cloning, Molecular ,4alpha glucanotransferase ,enzyme inhibition ,Mathematical models ,Ecology ,biology ,CYCLODEXTRIN-GLYCOSYLTRANSFERASE ,gene product ,starch ,article ,hyperthermophilic archaeon ,enzyme activity ,pH effects ,Biochemistry ,ESCHERICHIA-COLI ,glycosidase ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,chemical reaction kinetics ,enzyme active site ,pyrococcus-furiosus ,ARCHAEON THERMOCOCCUS-LITORALIS ,Biotechnology ,HYPERTHERMOPHILIC ARCHAEON ,gelatin ,Escherichia coli ,oligosaccharide ,Pyrobaculum aerophilum IM2 ,DISPROPORTIONATING ENZYME ,Nutrition ,enzyme substrate complex ,Solanum tuberosum ,Enzyme substrate complex ,nonhuman ,Binding Sites ,Enzyme kinetics ,dithiothreitol ,crystal-structure ,biology.organism_classification ,Heat ,Archaea ,thermostability ,enzyme ,Kinetics ,gene expression ,Gels ,disproportionating enzyme ,disulfide ,Food Science - Abstract
Amylomaltases are 4-α-glucanotransferases (EC 2.4.1.25) of glycoside hydrolase family 77 that transfer α-1,4-linked glucans to another acceptor, which can be the 4-OH group of an α-1,4-linked glucan or glucose. The amylomaltase-encoding gene (PAE1209) from the hyperthermophilic archaeon Pyrobaculum aerophilum IM2 was cloned and expressed in Escherichia coli , and the gene product (PyAMase) was characterized. PyAMase displays optimal activity at pH 6.7 and 95°C and is the most thermostable amylomaltase described to date. The thermostability of PyAMase was reduced in the presence of 2 mM dithiothreitol, which agreed with the identification of two possible cysteine disulfide bridges in a three-dimensional model of PyAMase. The kinetics for the disproportionation of malto-oligosaccharides, inhibition by acarbose, and binding mode of the substrates in the active site were determined. Acting on gelatinized food-grade potato starch, PyAMase produced a thermoreversible starch product with gelatin-like properties. This thermoreversible gel has potential applications in the food industry. This is the first report on an archaeal amylomaltase.
- Published
- 2005