To improve security and privacy, we are moving our web pages and services from HTTP to HTTPS.
To give users of web services time to transition to HTTPS, we will support separate HTTP and HTTPS services until the end of 2017.
From January 2018 most HTTP traffic will be automatically redirected to HTTPS. [more...]
View this page in https
PROSITE documentation PDOC00495 [for PROSITE entry PS00572]

Glycosyl hydrolases family 1 signatures





Description

It has been shown [1,2,3,4] that the following glycosyl hydrolases can be, on the basis of sequence similarities, classified into a single family:

  • β-glucosidases (EC 3.2.1.21) from various bacteria such as Agrobacterium strain ATCC 21400, Bacillus polymyxa, and Caldocellum saccharolyticum.
  • Two plants (clover) β-glucosidases (EC 3.2.1.21).
  • Two different β-galactosidases (EC 3.2.1.23) from the archaebacteria Sulfolobus solfataricus (genes bgaS and lacS).
  • 6-phospho-β-galactosidases (EC 3.2.1.85) from various bacteria such as Lactobacillus casei, Lactococcus lactis, and Staphylococcus aureus.
  • 6-phospho-β-glucosidases (EC 3.2.1.86) from Escherichia coli (genes bglB and ascB) and from Erwinia chrysanthemi (gene arbB).
  • Plants myrosinases (EC 3.2.1.147) (sinigrinase) (thioglucosidase).
  • Mammalian lactase-phlorizin hydrolase (LPH) (EC 3.2.1.108 / EC 3.2.1.62). LPH, an integral membrane glycoprotein, is the enzyme that splits lactose in the small intestine. LPH is a large protein of about 1900 residues which contains four tandem repeats of a domain of about 450 residues which is evolutionary related to the above glycosyl hydrolases.

One of the conserved regions in these enzymes is centered on a conserved glutamic acid residue which has been shown [5], in the β-glucosidase from Agrobacterium, to be directly involved in glycosidic bond cleavage by acting as a nucleophile. We have used this region as a signature pattern. As a second signature pattern we selected a conserved region, found in the N-terminal extremity of these enzymes, this region also contains a glutamic acid residue.

Note:

This pattern will pick up the last two domains of LPH; the first two domains, which are removed from the LPH precursor by proteolytic processing, have lost the active site glutamate and may therefore be inactive [4].

Consensus pattern:

F-x-[FYWM]-[GSTA]-x-[GSTA]-x-[GSTA](2)-[FYNH]-[NQ]-x-E-x- [GSTA]

Sequences known to belong to this class detected by the pattern:

ALL.

Other sequence(s) detected in Swiss-Prot:

NONE.

Note:

This pattern will pick up the last three domains of LPH.

Expert(s) to contact by email:

Henrissat B.

Last update:

November 1995 / Patterns and text revised.

Technical section

PROSITE methods (with tools and information) covered by this documentation:

GLYCOSYL_HYDROL_F1_1, PS00572; Glycosyl hydrolases family 1 active site  (PATTERN)

GLYCOSYL_HYDROL_F1_2, PS00653; Glycosyl hydrolases family 1 N-terminal signature  (PATTERN)


References

1AuthorsHenrissat B.
TitleA classification of glycosyl hydrolases based on amino acid sequence similarities.
SourceBiochem. J. 280:309-316(1991).
PubMed ID1747104

2AuthorsHenrissat B.
TitleSequence homology between a beta-galactosidase and some beta-glucosidases.
SourceProtein Seq. Data Anal. 4:61-62(1991).
PubMed ID1924272

3AuthorsGonzalez-Candelas L., Ramon D., Polaina J.
SourceGene 95:31-38(1990).

4AuthorsEl Hassouni M., Henrissat B., Chippaux M., Barras F.
SourceJ. Bacteriol. 174:765-777(1992).

5AuthorsWithers S.G., Warren R.A.J., Street I.P., Rupitz K., Kempton J.B., Aebersold R.
SourceJ. Am. Chem. Soc. 112:5887-5889(1990).



PROSITE is copyright. It is produced by the SIB Swiss Institute Bioinformatics. There are no restrictions on its use by non-profit institutions as long as its content is in no way modified. Usage by and for commercial entities requires a license agreement. For information about the licensing scheme send an email to
Prosite License or see: prosite_license.html.

Miscellaneous

View entry in original PROSITE document format
View entry in raw text format (no links)