3 Ontology Annotations
| GO Term | Gene Name |
|---|---|
| GO:0004553 | IPR013776 |
| GO:0005509 | IPR013776 |
| GO:0005975 | IPR013776 |
| Type: | Family | Name: | Alpha-amylase, thermostable |
| Description: | O-Glycosyl hydrolases () are a widespread group of enzymes that hydrolyse the glycosidic bond between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. A classification system for glycosyl hydrolases, based on sequence similarity, has led to the definition of 85 different families [, ]. This classification is available on the CAZy (CArbohydrate-Active EnZymes) web site.Alpha-amylase is classified as family 13 of the glycosyl hydrolases and is present in archaea, bacteria, plants and animals. Alpha-amylase is an essential enzyme in alpha-glucan metabolism, acting to catalyse the hydrolysis of alpha-1,4-glucosidic bonds of glycogen, starch and related polysaccharides. Although all alpha-amylases possess the same catalytic function, they can vary with respect to sequence. In general, they are composed of three domains: a TIM barrel containing the active site residues and chloride ion-binding site (domain A), a long loop region inserted between the third beta strand and the alpha-helix of domain A that contains calcium-binding site(s) (domain B), and a C-terminal beta-sheet domain that appears to show some variability in sequence and length between amylases (domain C) []. Amylases have at least one conserved calcium-binding site, as calcium is essential for the stability of the enzyme. The chloride-binding functions to activate the enzyme, which acts by a two-step mechanism involving a catalytic nucleophile base (usually an Asp) and a catalytic proton donor (usually a Glu) that are responsible for the formation of the beta-linked glycosyl-enzyme intermediate. This entry represents a subfamily of alpha-amylase proteins that are highly thermostable. Studies on amylases with different thermostabilities have revealed several structural and dynamic features that can affect thermal adaptation []. One of these features is the number of calcium-binding sites that the enzyme contains, with extra calcium-binding sites contributing to structural stability [, ]. | Short Name: | A-amylase_thermo |
| GO Term | Gene Name |
|---|---|
| GO:0004553 | IPR013776 |
| GO:0005509 | IPR013776 |
| GO:0005975 | IPR013776 |
