1XSK

Structure of a Family 31 alpha glycosidase glycosyl-enzyme intermediate

Summary for 1XSK

• Entry DOI: 10.2210/pdb1xsk/pdb
• Related: 1XSI 1XSJ
• Descriptor: Putative family 31 glucosidase yicI, SULFATE ION, 5(R)-fluoro-beta-D-xylopyranose, ... (5 entities in total)
• Functional Keywords: beta(8)alpha(8) barrel and beta sandwich domains, hydrolase
• Biological source: Escherichia coli
• Total number of polymer chains: 6
• Total formula weight: 536766.46

Authors

Lovering, A.L.,Lee, S.S.,Kim, Y.W.,Withers, S.G.,Strynadka, N.C. (deposition date: 2004-10-19, release date: 2004-11-10, Last modification date: 2024-10-30)

Primary citation

Lovering, A.L.,Lee, S.S.,Kim, Y.W.,Withers, S.G.,Strynadka, N.C.
Mechanistic and Structural Analysis of a Family 31 {alpha}-Glycosidase and Its Glycosyl-enzyme Intermediate
J.Biol.Chem., 280:2105-2115, 2005

PubMed Abstract: We have determined the first structure of a family 31 alpha-glycosidase, that of YicI from Escherichia coli, both free and trapped as a 5-fluoroxylopyranosyl-enzyme intermediate via reaction with 5-fluoro-alpha-D-xylopyranosyl fluoride. Our 2.2-A resolution structure shows an intimately associated hexamer with structural elements from several monomers converging at each of the six active sites. Our kinetic and mass spectrometry analyses verified several of the features observed in our structural data, including a covalent linkage from the carboxylate side chain of the identified nucleophile Asp(416) to C-1 of the sugar ring. Structure-based sequence comparison of YicI with the mammalian alpha-glucosidases lysosomal alpha-glucosidase and sucrase-isomaltase predicts a high level of structural similarity and provides a foundation for understanding the various mutations of these enzymes that elicit human disease.

PubMed: 15501829
DOI: 10.1074/jbc.M410468200

Experimental method

X-RAY DIFFRACTION (2.2 Å)