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- *********************************************
- * Glucoamylase active site region signature *
- *********************************************
-
- Glucoamylase (GA) (EC 3.2.1.3) is an enzyme that catalyzes the release of D-
- glucose from the non-reducing ends of starch and other oligo- or
- polysaccharides. Extensive studies of fungal GA have shown [1] that three
- closely clustered acidic residues play a role in the catalytic mechanism of
- GA. The region that includes these residues is also conserved in a recently
- sequenced bacterial GA [2]. We used this region as a signature pattern.
-
- -Consensus pattern: [STN]-G-x(1,2)-[DE]-x-W-E-E-x(2)-G
- [All D/E are active site residues]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Note: these proteins belong to family 15 in the classification of glycosyl
- hydrolases [3].
- -Note: a GA from Schwanniomyces occidentalis is not a member of this family
- but belongs to family 31 (see the relevant entry).
-
- -Last update: October 1993 / First entry.
-
- [ 1] Sierks M.R., Ford C., Reilly P.J., Svensson B.
- Protein Eng. 3:193-198(1990) .
- [ 2] Ohnishi H., Kitamura H., Minowa T., Sakai H., Ohta T.
- Eur. J. Biochem. 207:413-418(1992).
- [ 3] Henrissat B.
- Biochem. J. 280:309-316(1991).
-