Glycoside hydrolase family 36

Melibiase
crystal structure of rice alpha-galactosidase
Identifiers
Symbol	Melibiase
Pfam	PF02065
Pfam clan	CL0058
InterPro	IPR000111
SCOP2	1ktc / SCOPe / SUPFAM
CAZy	GH36
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

Raffinose_syn
Identifiers
Symbol	Raffinose_syn
Pfam	PF05691
Pfam clan	CL0058
InterPro	IPR008811
CAZy	GH36
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

In molecular biology, glycoside hydrolase family 36 is a family of glycoside hydrolases.

Glycoside hydrolases EC 3.2.1. 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 glycoside hydrolases, based on sequence similarity, has led to the definition of >100 different families.[1][2][3] This classification is available on the CAZy web site,[4][5] and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes.[6][7]

Glycoside hydrolase family 36 together with family 31 and family 27 alpha-galactosidases form the glycosyl hydrolase clan GH-D, a superfamily of alpha-galactosidases, alpha-N-acetylgalactosaminidases, and isomaltodextranases which are likely to share a common catalytic mechanism and structural topology.

Alpha-galactosidase (EC 3.2.1.22) (melibiase)[8] catalyzes the hydrolysis of melibiose into galactose and glucose. In man, the deficiency of this enzyme is the cause of Fabry's disease (X-linked sphingolipidosis). Alpha-galactosidase is present in a variety of organisms. There is a considerable degree of similarity in the sequence of alpha-galactosidase from various eukaryotic species. Escherichia coli alpha-galactosidase (gene melA), which requires NAD and magnesium as cofactors, is not structurally related to the eukaryotic enzymes; by contrast, an Escherichia coli plasmid encoded alpha-galactosidase (gene rafA P16551)[9] contains a region of about 50 amino acids which is similar to a domain of the eukaryotic alpha-galactosidases. Alpha-N-acetylgalactosaminidase (EC 3.2.1.49)[10] catalyzes the hydrolysis of terminal non-reducing N-acetyl-D-galactosamine residues in N-acetyl-alpha-D- galactosaminides. In man, the deficiency of this enzyme is the cause of Schindler and Kanzaki diseases. The sequence of this enzyme is highly related to that of the eukaryotic alpha-galactosidases.

This family also includes raffinose synthase proteins, also known as seed inhibition (Sip1) proteins. Raffinose (O-alpha- D-galactopyranosyl- (1-->6)- O-alpha- D-glucopyranosyl-(1<-->2)- O-beta- D-fructofuranoside) is a widespread oligosaccharide in plant seeds and other tissues. Raffinose synthase EC 2.4.1.82 is the key enzyme that channels sucrose into the raffinose oligosaccharide pathway.[11]

Glycoside hydrolase family 36 also includes enzymes with α-N-acetylgalactosaminidase EC 3.2.1.49 and stachyose synthase EC 2.4.1.67 activities.

Glycoside hydrolase family 36 can be subdivided into 11 families, GH36A to GH36K.[12]

References

1. Henrissat B, Callebaut I, Mornon JP, Fabrega S, Lehn P, Davies G (1995). "Conserved catalytic machinery and the prediction of a common fold for several families of glycosyl hydrolases". Proc. Natl. Acad. Sci. U.S.A. 92 (15): 7090–7094. Bibcode:1995PNAS...92.7090H. doi:10.1073/pnas.92.15.7090. PMC 41477. PMID 7624375.
2. Henrissat B, Davies G (1995). "Structures and mechanisms of glycosyl hydrolases". Structure. 3 (9): 853–859. doi:10.1016/S0969-2126(01)00220-9. PMID 8535779.
3. "Bairoch, A. "Classification of glycosyl hydrolase families and index of glycosyl hydrolase entries in SWISS-PROT". 1999". Archived from the original on 2011-05-25. Retrieved 2011-11-08.
4. "Home". CAZy.org. Retrieved 2018-03-06.
5. Lombard, Vincent; Golaconda Ramulu, Hemalatha; Drula, Elodie; Coutinho, Pedro M.; Henrissat, Bernard (2014-01-01). "The carbohydrate-active enzymes database (CAZy) in 2013". Nucleic Acids Research. 42 (D1): D490 – D495. doi:10.1093/nar/gkt1178. ISSN 0305-1048. PMC 3965031. PMID 24270786.
6. "Glycoside Hydrolase Family 36". CAZypedia.org. Retrieved 2018-03-06.
7. CAZypedia Consortium (2018-12-01). "Ten years of CAZypedia: a living encyclopedia of carbohydrate-active enzymes" (PDF). Glycobiology. 28 (1): 3–8. doi:10.1093/glycob/cwx089. ISSN 1460-2423. PMID 29040563.
8. Dey PM, Pridham JB (1972). "Biochemistry of -galactosidases". Adv. Enzymol. Relat. Areas Mol. Biol. 36: 91–120. doi:10.1002/9780470122815.ch3. PMID 4561015.
9. Aslanidis C, Schmid K, Schmitt R (1989). "Nucleotide sequences and operon structure of plasmid-borne genes mediating uptake and utilization of raffinose in Escherichia coli". J. Bacteriol. 171 (12): 6753–6763. doi:10.1128/jb.171.12.6753-6763.1989. PMC 210573. PMID 2556373.
10. Wang AM, Bishop DF, Desnick RJ (1990). "Human alpha-N-acetylgalactosaminidase-molecular cloning, nucleotide sequence, and expression of a full-length cDNA. Homology with human alpha-galactosidase A suggests evolution from a common ancestral gene". J. Biol. Chem. 265 (35): 21859–21866. doi:10.1016/S0021-9258(18)45818-8. PMID 2174888.
11. Peterbauer T, Mach L, Mucha J, Richter A (September 2002). "Functional expression of a cDNA encoding pea (Pisum sativum L.) raffinose synthase, partial purification of the enzyme from maturing seeds, and steady-state kinetic analysis of raffinose synthesis". Planta. 215 (5): 839–46. Bibcode:2002Plant.215..839P. doi:10.1007/s00425-002-0804-7. PMID 12244450. S2CID 449826.
12. Naumoff DG (2011). "Hierarchical classification of glycoside hydrolases". Biochemistry (Moscow). 76 (6): 622–35. doi:10.1134/S0006297911060022. PMID 21639842. S2CID 206838603.

External links

• GH36 in CAZypedia

External links

• GH36 on CAZypedia

This article incorporates text from the public domain Pfam and InterPro: IPR000111