Title: Amylase
CAS Registry Number: 9000-92-4
Literature References: Enzymes catalyzing the hydrolysis of a-1?4 glucosidic linkages of polysaccharides such as glycogen, starch, or their degradation products.
Endoamylases attack the a-1?4 linkage at random. A single type of endoamylase is known,
i.e., a-amylases (
a-1,4-glucan 4-glucanohydrolases), so named, because the reducing hemiacetal group liberated by the hydrolysis has a optical configuration and mutarotates downward. The more common a-amylases include those isolated from human saliva, human, hog and rat pancreas,
Bacillus subtilis, B. coagulans, Aspergillus oryzae, A. candidus, Pseudomonas saccharophila, and barley malt.
Exoamylases attack the a-1?4 linkages only from the non-reducing outer polysaccharide chain ends. Those breaking every glucosidic bond to produce solely a-glucose are known as
glucoamylases (
g-amylases). Those breaking every alternate bond to produce maltose are known as b-amylases (
a-1,4-glucan maltohydrolases). Exoamylases are exclusively of vegetable or microbial origin.
Reviews: Fischer, Stein, "a-Amylases" and French, "b-Amylases" in
The Enzymes Vol. 4, P. D. Boyer
et al., Eds., (Academic Press, New York, 2nd ed., 1960) pp 313-343, 345-368; J. A. Thoma
et al., ibid. Vol. V (3rd ed., 1971) pp 115-189; W. M. Fogarty, C. T. Kelly,
Microbial Enzymes and Bioconversions, A. H. Rose, Ed. (Academic Press, New York, 1980) pp 115-170.
Derivative Type: a-Amylase (porcine)
CAS Registry Number: 9000-90-2
Trademarks: Maxilase (Sanofi Winthrop)
Literature References: Enzyme derived from swine pancrease. mol wt ~45,000. Prepn: Caldwell
et al., J. Am. Chem. Soc. 74, 4033 (1952).
Derivative Type: a-Amylase (bacterial)
CAS Registry Number: 9000-85-5
Literature References: Usually derived from
Bacillus subtilis. Purification: Stein, Fischer,
Helv. Chim. Acta 40, 529 (1957).
Derivative Type: b-Amylase (sweet potato)
CAS Registry Number: 9000-91-3
Literature References: Mol wt ~152,000. Prepn: Balls
et al., J. Biol. Chem. 173, 9 (1948).
Use: In starch processing, brewing, distilling, baking, animal feed, sewage treatment.
Therap-Cat: Enzyme (digestive aid).
Keywords: Digestive Aid; Enzyme; Digestive.
