Glycoside hydrolase family 36

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
PDB 1uas EBI.jpg
crystal structure of rice alpha-galactosidase
Symbol Melibiase
Pfam PF02065
Pfam clan CL0058
InterPro IPR000111
SCOP 1ktc
Symbol Raffinose_syn
Pfam PF05691
Pfam clan CL0058
InterPro IPR008811

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 (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[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 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 and stachyose synthase EC activities.

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

External links[edit]


  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. doi:10.1073/pnas.92.15.7090. PMC 41477Freely accessible. 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.
  4. ^ "Home". 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. 
  6. ^ "Glycoside Hydrolase Family 36". Retrieved 2018-03-06. 
  7. ^ CAZypedia Consortium (2018-12-01). "Ten years of CAZypedia: a living encyclopedia of carbohydrate-active enzymes". 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. 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. PMC 210573Freely accessible. 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. 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. doi:10.1007/s00425-002-0804-7. PMID 12244450. 
  12. ^ Naumoff DG (2011). "Hierarchical classification of glycoside hydrolases". Biochemistry (Mosc). 76 (6): 622–35. doi:10.1134/S0006297911060022. PMID 21639842. 

External links[edit]

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