Gene sequence and crystal structure of the aldehyde oxidoreductase from Desulfovibrio desulfuricans ATCC 27774

Citation
J. Rebelo et al., Gene sequence and crystal structure of the aldehyde oxidoreductase from Desulfovibrio desulfuricans ATCC 27774, J MOL BIOL, 297(1), 2000, pp. 135-146
Citations number
42
Categorie Soggetti
Molecular Biology & Genetics
Journal title
JOURNAL OF MOLECULAR BIOLOGY
ISSN journal
00222836 → ACNP
Volume
297
Issue
1
Year of publication
2000
Pages
135 - 146
Database
ISI
SICI code
0022-2836(20000317)297:1<135:GSACSO>2.0.ZU;2-S
Abstract
The aldehyde oxidoreductase (MOD) isolated from the sulfate reducer Desulfo vibrio desulfuricans (ATCC 27774) is a member of the xanthine oxidase famil y of molybdenum-containing enzymes. It has substrate specificity similar to that of the homologous enzyme from Desulfovibrio gigas (MOP) and the prima ry sequences from both enzymes show 68 % identity. The enzyme was crystalli zed in space group P6(1)22, with unit cell dimensions of of a = b = 156.4 A ngstrom and c = 177.1 Angstrom, and diffraction data were obtained to beyon d 2.8 Angstrom. The crystal structure was solved by Patterson search techni ques using the coordinates of the D. gigas enzyme. The overall fold of the D. desulfuricans enzyme is very similar to MOP and the few differences are mapped to exposed regions of the molecule. This is reflected in the electro static potential surfaces of both homologous enzymes, one exception being t he surface potential in a region identifiable as the putative docking site of the physiological electron acceptor. Other essential features of the MOP structure, such as residues of the active-site cavity, are basically conse rved in MOD. Two mutations are located in the pocket bearing a chain of cat alytically relevant water molecules. As deduced from this work, both these enzymes are very closely related in t erms of their sequences as well as 3D structures. The comparison allowed co nfirmation and establishment of features that are essential for their funct ion; namely, conserved residues in the active-site, catalytically relevant water molecules and recognition of the physiological electron acceptor dock ing site. (C) 2000 Academic Press.