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It has been shown [1,2,E1] that the following glycosyl hydrolases can be, on the basis of sequence similarities, classified into a single family:

• β-galactosidases (EC 3.2.1.23) from bacteria such as Escherichia coli (genes lacZ and ebgA), Clostridium acetobutylicum, Clostridium thermosulfurogenes, Klebsiella pneumoniae, Lactobacillus delbrueckii, or Streptococcus thermophilus and from the fungi Kluyveromyces lactis.
• β-glucuronidase (EC 3.2.1.31) from Escherichia coli (gene uidA) and from mammals.

One of the conserved regions in these enzymes is centered on a conserved glutamic acid residue which has been shown [3], in Escherichia coli lacZ, to be the general acid/base catalyst in the active site of the enzyme. We have used this region as a signature pattern. As a second signature pattern we selected a highly conserved region located some sixty residues upstream from the active site glutamate.

Henrissat B.

April 2006 / Pattern revised.

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

GLYCOSYL_HYDROL_F2_1, PS00719; Glycosyl hydrolases family 2 signature 1  (PATTERN)

Consensus pattern: N-x-[LIVMFYWD]-R-[STACN](2)-H-Y-P-x(4)-[LIVMFYWS](2)-x(3)-[DN]-x(2)-G-[LIVMFYW](4) Sequences known to belong to this class detected by the pattern: ALL Other sequence(s) detected in Swiss-Prot: NONE.

• Retrieve an alignment of Swiss-Prot true positive hits:   Clustal format, color, condensed view  / Clustal format, color  / Clustal format, plain text  / Fasta format • Retrieve the sequence logo from the alignment • Taxonomic tree view of all Swiss-Prot/TrEMBL entries matching PS00719 • Retrieve a list of all Swiss-Prot/TrEMBL entries matching PS00719 • Scan Swiss-Prot/TrEMBL entries against PS00719 • view ligand binding statistics

Matching PDB structures: 1BGL 1BGM 1BHG 1DP0 ... [ALL]

GLYCOSYL_HYDROL_F2_2, PS00608; Glycosyl hydrolases family 2 acid/base catalyst  (PATTERN)

Consensus pattern: [DENQLF]-[KRVW]-N-[HRY]-[STAPV]-[SAC]-[LIVMFS]-[LIVMFSA]-[LIVMFS]-W-[GSV]-x(2,3)-N-E E is the active site residue Sequences known to belong to this class detected by the pattern: ALL, except for Rhizobium meliloti lacZ Other sequence(s) detected in Swiss-Prot: NONE.

• Retrieve an alignment of Swiss-Prot true positive hits:   Clustal format, color, condensed view  / Clustal format, color  / Clustal format, plain text  / Fasta format • Retrieve the sequence logo from the alignment • Taxonomic tree view of all Swiss-Prot/TrEMBL entries matching PS00608 • Retrieve a list of all Swiss-Prot/TrEMBL entries matching PS00608 • Scan Swiss-Prot/TrEMBL entries against PS00608 • view ligand binding statistics

Matching PDB structures: 1BGL 1BGM 1BHG 1DP0 ... [ALL]

1	Authors	Henrissat B.
	Title	A classification of glycosyl hydrolases based on amino acid sequence similarities.
	Source	Biochem. J. 280:309-316(1991).
	PubMed ID	1747104

2	Authors	Schroeder C.J., Robert C., Lenzen G., McKay L.L., Mercenier A.
	Title	Analysis of the lacZ sequences from two Streptococcus thermophilus strains: comparison with the Escherichia coli and Lactobacillus bulgaricus beta-galactosidase sequences.
	Source	J. Gen. Microbiol. 137:369-380(1991).
	PubMed ID	1901904

3	Authors	Gebler J.C., Aebersold R., Withers S.G.
	Title	Glu-537, not Glu-461, is the nucleophile in the active site of (lac Z) beta-galactosidase from Escherichia coli.
	Source	J. Biol. Chem. 267:11126-11130(1992).
	PubMed ID	1350782

E1
Source	http://www.uniprot.org/docs/glycosid

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