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- *******************************************
- * Glycosyl hydrolases family 17 signature *
- *******************************************
-
- It has been shown [1,2] that the following glycosyl hydrolases can be, on the
- basis of sequence similarities, classified into a single family:
-
- - Glucan endo-1,3-beta-glucosidases (EC 3.2.1.39) (endo-(1->3)-beta-
- glucanase) from various plants. This enzyme may be involved in the defense
- of plants against pathogens through its ability to degrade fungal cell wall
- polysaccharides.
- - Glucan 1,3-beta-glucosidase (EC 3.2.1.58) (exo-(1->3)-beta-glucanase) from
- yeast (gene BGL2). This enzyme may play a role in cell expansion during
- growth, in cell-cell fusion during mating, and in spore release during
- sporulation.
- - Lichenases (EC 3.2.1.73) (endo-(1->3,1->4)-beta-glucanase) from various
- plants.
-
- The best conserved region in the sequence of these enzymes is located in their
- central section. This region contains a conserved tryptophan residue which
- could be involved in the interaction with the glucan substrates [2] and it
- also contains a conserved glutamate which could be involved in the catalytic
- mechanism. We have used this region as a signature pattern.
-
- -Consensus pattern: [LIVM]-x-[LIVMFYW](3)-[STAG]-E-[ST]-G-W-P-[ST]-x-G
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Expert(s) to contact by email: Henrissat B.
- bernie@cermav.grenet.fr
-
- -Last update: December 1992 / Text revised.
-
- [ 1] Henrissat B.
- Biochem. J. 280:309-316(1991).
- [ 2] Ori N., Sessa G., Lotan T., Himmelhoch S., Fluhr R.
- EMBO J. 9:3429-3436(1990).
-