Open AccessExpression, purification, crystallization and preliminary X‐ray crystallographic analysis of human β‐galactosidase
Author(s) -
Usui Kimihito,
Ohto Umeharu,
Ochi Toshinari,
Shimizu Toshiyuki,
Satow Yoshinori
Publication year - 2012
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309111047920
Subject(s) - exoglycosidase , crystallization , crystallography , chemistry , galactose , keratan sulfate , glycoprotein , biochemistry , glycan , proteoglycan , organic chemistry , extracellular matrix
β‐ d ‐Galactosidase (β‐Gal) is an exoglycosidase that cleaves β‐galactosides from glycoproteins, sphingolipids and keratan sulfate. This study reports the expression, purification, crystallization and preliminary X‐ray crystallographic analysis of human lysosomal β‐Gal. The sitting‐drop vapour‐diffusion method was used to crystallize β‐Gal in complexes with its product galactose and with the inhibitor 1‐deoxygalactonojirimycin. The resulting crystals were isomorphous and belonged to space group P 2 1 . The crystals of the β‐Gal–galactose and the β‐Gal–inhibitor complexes had unit‐cell parameters a = 94.8, b = 116.1, c = 140.3 Å, β = 92.2° and a = 94.8, b = 116.0, c = 140.3 Å, β = 92.2°, respectively. Diffraction data were collected to 1.8 Å resolution for both crystals.