Open AccessTowards the crystal structure elucidation of eukaryotic UDP‐galactopyranose mutase
Author(s) -
van Straaten Karin E.,
Routier Francoise H.,
Sanders David A. R.
Publication year - 2012
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309112006914
Subject(s) - mutase , crystal structure , crystallography , chemistry , computational biology , materials science , biochemistry , biology , enzyme
UDP‐galactopyranose mutase (UGM) catalyzes the interconversion of UDP‐galactopyranose and UDP‐galactofuranose. Eukaryotic UGMs from Aspergillus fumigatus and Leishmania major have been purified to homogeneity by means of Ni 2+ ‐affinity chromatography and crystallized. Eukaryotic UGM structure elucidation was not straightforward owing to high pseudo‐symmetry, twinning and very low anomalous signal. Phasing to 2.8 Å resolution using SAD was successful for L. major UGM. However, the maps could only be improved by iterative density modification and manual model building. High pseudo‐symmetry and twinning prevented correct space‐group assignment and the completion of structure refinement. The structure of A. fumigatus UGM to 2.52 Å resolution was determined by molecular replacement using the incomplete 2.8 Å resolution L. major UGM model.