Isocitrate lyase from Aspergillus nidulans: crystallization and X-ray analysis of a glyoxylate cycle enzyme.
Isocitrate lyase (ICL) from the filamentous fungus Aspergillus nidulans catalyzes the first committed step of the carbon-conserving glyoxylate bypass. This enzyme has been crystallized by the hanging-drop method of vapour diffusion using polyethylene glycol 2000 as the precipitant. Diffraction patterns show that the crystals diffract to beyond 2.5 A and are probably in space group P4(2)2(1)2 with unit-cell dimensions of a = b = 91.9 and c = 152.7 A, with one molecule in the asymmetric unit. The elucidation of the structure of this enzyme to high resolution will advance the understanding of how the metabolic branch point between the tricarboxylic acid cycle and the glyoxylate bypass is controlled by the affinity of ICL for its substrate isocitrate and contribute to a programme of rational drug design.
Krebs Institute for Biomolecular Research, Department of Molecular Biology and Biotechnology, The University of Sheffield, England.
S J
SJ
Langridge
P J
PJ
Baker
J R
JR
DeLucas
S E
SE
Sedelnikova
G
G
Turner
D W
DW
Rice