Glycoside hydrolase family 27

Melibiase
crystal structure of rice alpha-galactosidase
Identifiers
Symbol Melibiase
Pfam PF02065
Pfam clan CL0058
InterPro IPR000111
SCOP 1ktc
CAZy GH27

In molecular biology, glycoside hydrolase family 27 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(http://www.cazy.org/GH1.html) web site,[4] and also discussed at CAZypedia, an online encyclopedia of carbohydrate active enzymes. [5]

Glycoside hydrolase family 27 together with family 31 and the family 36 alpha-galactosidases form the glycosyl hydrolase clan GH-D (CAZY GH), 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)[6] 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)[7] 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)[8] 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.

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. doi:10.1073/pnas.92.15.7090. PMC 41477. PMID 7624375. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=41477. 
  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. ^ Henrissat, B. and Coutinho P.M. "Carbohydrate-Active Enzymes server". 1999.
  5. ^ CAZypedia, an online encyclopedia of carbohydrate-active enzymes.
  6. ^ Dey PM, Pridham JB (1972). "Biochemistry of -galactosidases". Adv. Enzymol. Relat. Areas Mol. Biol. 36: 91–120. PMID 4561015. 
  7. ^ 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 210573. PMID 2556373. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=210573. 
  8. ^ 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. 

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