Exploring and exploiting starch-modifying amylomaltases from thermophiles.
Starch is a staple food present in water-insoluble granules in many economically important crops. It is composed of two glucose polymers: the linear alpha-1,4-linked amylose and amylopectin with a backbone of alpha-1,4-glycosidic bonds and alpha-1,6-linked side chains. To dissolve starch completely in water it needs to be heated; when it cools down too much the starch solution forms a thermo-irreversible gel. Amylomaltases (EC 2.4.1.25) are enzymes that transfer a segment of an alpha-1,4-D-glucan to a new 4-position in an acceptor, which may be glucose or another alpha-1,4-D-glucan. Acting upon starch, amylomaltases can produce cycloamylose or a thermoreversible starch gel, both of which are of commercial interest.
Kaper
T
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Centre for Carbohydrate Bioengineering TNO-RUG, P.O. Box 14, 9750 AA Haren, The Netherlands.
van der Maarel
M J E C
MJ
Euverink
G J W
GJ
Dijkhuizen
L
L
D000687:Amylopectin / Q000737:chemistry; D000688:Amylose / Q000737:chemistry; D001105:Archaea / Q000201:enzymology*; D005936:Glucans / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D006004:Glycogen Debranching Enzyme System / Q000737:chemistry*; D006026:Glycoside Hydrolases / Q000737:chemistry; D006358:Hot Temperature; D008958:Models, Molecular; D011108:Polymers / Q000737:chemistry*; D013213:Starch / Q000737:chemistry*; D013997:Time Factors
D005936:Glucans; D006004:Glycogen Debranching Enzyme System; D011108:Polymers; D013213:Starch; D000688:Amylose; D000687:Amylopectin; C020569:4 alpha-glucanotransferase; D006026:Glycoside Hydrolases; D005947:Glucose