{PDOC00910} {PS01182; GLYCOSYL_HYDROL_F35} {BEGIN} ****************************************************** * Glycosyl hydrolases family 35 putative active site * ****************************************************** Beta-galactosidases (EC 3.2.1.23) from mammals, fungi, plants and the bacteria Xanthomonas manihotis are evolutionary related [1,2]. They belong to family 35 in the classification of glycosyl hydrolases [3,E1]. Mammalian beta-galactosidase is a lysosomal enzyme (gene GLB1) which cleaves the terminal galactose from gangliosides, glycoproteins, and glycosaminoglycans and whose deficiency is the cause of the genetic disease Gm(1) gangliosidosis (Morquio disease type B). On of the best conserved regions in these enzymes contains a glutamic acid residue which, on the basis of similarities with other families of glycosyl hydrolases [4], probably acts as the proton donor in the catalytic mechanism. We use this region as a signature pattern. -Consensus pattern: G-G-P-[LIVM](2)-x(2)-Q-x-E-N-E-[FY] [The second E may be the active site residue] -Sequences known to belong to this class detected by the pattern: ALL. -Other sequence(s) detected in Swiss-Prot: NONE. -Expert(s) to contact by email: Henrissat B.; bernie@afmb.cnrs-mrs.fr -Last update: May 2004 / Text revised. [ 1] Taron C.H., Benner J.S., Hornstra L.J., Guthrie E.P. "A novel beta-galactosidase gene isolated from the bacterium Xanthomonas manihotis exhibits strong homology to several eukaryotic beta-galactosidases." Glycobiology 5:603-610(1995). PubMed=8563148 [ 2] Carey A.T., Holt K., Picard S., Wilde R., Tucker G.A., Bird C.R., Schuch W., Seymour G.B. "Tomato exo-(1-->4)-beta-D-galactanase. Isolation, changes during ripening in normal and mutant tomato fruit, and characterization of a related cDNA clone." Plant Physiol. 108:1099-1107(1995). PubMed=7630937 [ 3] Henrissat B., Bairoch A. "New families in the classification of glycosyl hydrolases based on amino acid sequence similarities." Biochem. J. 293:781-788(1993). PubMed=8352747 [ 4] Henrissat B., Callebaut I., Fabrega S., Lehn P., Mornon J.-P., Davies G. "Conserved catalytic machinery and the prediction of a common fold for several families of glycosyl hydrolases." Proc. Natl. Acad. Sci. U.S.A. 92:7090-7094(1995). PubMed=7624375 [E1] https://www.uniprot.org/docs/glycosid -------------------------------------------------------------------------------- PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see https://prosite.expasy.org/prosite_license.html -------------------------------------------------------------------------------- {END}