Open AccessStructure of a Coenzyme A Pyrophosphatase from Deinococcus radiodurans : a Member of the Nudix Family
Author(s) -
Lin Woo Kang,
Sandra B. Gabelli,
M.A. Bianchet,
Wenyue Xu,
Maurice J. Bessman,
L. Mario Amzel
Publication year - 2003
Publication title -
journal of bacteriology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.652
H-Index - 246
eISSN - 1067-8832
pISSN - 0021-9193
DOI - 10.1128/jb.185.14.4110-4118.2003
Subject(s) - biology , pyrophosphatase , deinococcus radiodurans , inorganic pyrophosphatase , enzyme , biochemistry , gene , pyrophosphate
Gene Dr1184 from Deinococcus radiodurans codes for a Nudix enzyme (DR-CoAse) that hydrolyzes the pyrophosphate moiety of coenzyme A (CoA). Nudix enzymes with the same specificity have been found in yeast, humans, and mice. The three-dimensional structure of DR-CoAse, the first of a Nudix hydrolase with this specificity, reveals that this enzyme contains, in addition to the fold observed in other Nudix enzymes, insertions that are characteristic of a CoA-hydrolyzing Nudix subfamily. The structure of the complex of the enzyme with Mg(2+), its activating cation, reveals the position of the catalytic site. A helix, part of the N-terminal insertion, partially occludes the binding site and has to change its position to permit substrate binding. Comparison of the structure of DR-CoAse to those of other Nudix enzymes, together with the location in the structure of the sequence characteristic of CoAses, suggests a mode of binding of the substrate to the enzyme that is compatible with all available data.