1NZZ

Human mitochondrial aldehyde dehydrogenase complexed with NADH in the presence of low Mg2+

Summary for 1NZZ

• Entry DOI: 10.2210/pdb1nzz/pdb
• Related: 1A4Z 1AG8 1CW3 1NZW 1NZX 1O00 1O01 1O02 1O04 1O05
• Descriptor: Aldehyde dehydrogenase, SODIUM ION, MAGNESIUM ION, ... (5 entities in total)
• Functional Keywords: aldh, nad, nadh, isomerization, oxidoreductase
• Biological source: Homo sapiens (human)
• Cellular location: Mitochondrion matrix: P05091
• Total number of polymer chains: 8
• Total formula weight: 441698.92

Authors

Perez-Miller, S.J.,Hurley, T.D. (deposition date: 2003-02-20, release date: 2003-06-24, Last modification date: 2023-08-16)

Primary citation

Perez-Miller, S.J.,Hurley, T.D.
Coenzyme isomerization is integral to catalysis in aldehyde dehydrogenase
Biochemistry, 42:7100-7109, 2003

PubMed Abstract: Crystal structures of many enzymes in the aldehyde dehydrogenase superfamily determined in the presence of bound NAD(P)(+) have exhibited conformational flexibility for the nicotinamide half of the cofactor. This has been hypothesized to be important in catalysis because one conformation would block the second half of the reaction, but no firm evidence has been put forth which shows whether the oxidized and reduced cofactors preferentially occupy the two observed conformations. We present here two structures of the wild type and two structures of a Cys302Ser mutant of human mitochondrial aldehyde dehydrogenase in binary complexes with NAD(+) and NADH. These structures, including the Cys302Ser mutant in complex with NAD(+) at 1.4 A resolution and the wild-type enzyme in complex with NADH at 1.9 A resolution, provide strong evidence that bound NAD(+) prefers an extended conformation ideal for hydride transfer and bound NADH prefers a contracted conformation ideal for acyl-enzyme hydrolysis. Unique interactions between the cofactor and the Rossmann fold make isomerization possible while allowing the remainder of the active site complex to remain intact. In addition, these structures clarify the role of magnesium in activating the human class 2 enzyme. Our data suggest that the presence of magnesium may lead to selection of particular conformations and speed isomerization of the reduced cofactor following hydride transfer.

PubMed: 12795606
DOI: 10.1021/bi034182w

Experimental method

X-RAY DIFFRACTION (2.45 Å)