1ADC

CRYSTALLOGRAPHIC STUDIES OF ISOSTERIC NAD ANALOGUES BOUND TO ALCOHOL DEHYDROGENASE: SPECIFICITY AND SUBSTRATE BINDING IN TWO TERNARY COMPLEXES

Summary for 1ADC

• Entry DOI: 10.2210/pdb1adc/pdb
• Descriptor: ALCOHOL DEHYDROGENASE, ZINC ION, 5-BETA-D-RIBOFURANOSYLPICOLINAMIDE ADENINE-DINUCLEOTIDE, ... (5 entities in total)
• Functional Keywords: oxidoreductase (nad(a)-choh(d))
• Biological source: Equus caballus (horse)
• Cellular location: Cytoplasm: P00327
• Total number of polymer chains: 2
• Total formula weight: 81387.17

Authors

Li, H.,Hallows, W.A.,Punzi, J.S.,Pankiewicz, K.W.,Watanabe, K.A.,Goldstein, B.M. (deposition date: 1993-12-13, release date: 1995-06-03, Last modification date: 2024-02-07)

Primary citation

Li, H.,Hallows, W.H.,Punzi, J.S.,Pankiewicz, K.W.,Watanabe, K.A.,Goldstein, B.M.
Crystallographic studies of isosteric NAD analogues bound to alcohol dehydrogenase: specificity and substrate binding in two ternary complexes.
Biochemistry, 33:11734-11744, 1994

PubMed Abstract: CNAD (5-beta-D-ribofuranosylnicotinamide adenine dinucleotide) is an isosteric C-glycosidic analogue of NAD(H) containing a neutral pyridine ring. CPAD (5-beta-D-ribofuranosylpicolinamide adenine dinucleotide) is a closely related pyridine-containing analogue with the pyridine nitrogen on the opposite side of the ring. CNAD is a potent and specific inhibitor of horse liver alcohol dehydrogenase (LADH), binding with a dissociation constant in the nanomolar range. CPAD binds LADH with an affinity comparable to that of NAD. Crystal structures of CNAD and CPAD bound to LADH are presented at 2.4 and 2.7 A, respectively. The two complexes are isomorphous, crystallizing in the triclinic system with cell dimensions different from those seen in previous ternary LADH complexes. Structures were solved using the molecular replacement method and refined to crystallographic R values of 18% (CNAD) and 17% (CPAD). Both inhibitors bind to the "closed" form of LADH in the normal cofactor-binding cleft. The conformation of LADH-bound CPAD closely mimics that of LADH-bound NAD(H). The data suggest that alcohol substrate binds directly to the catalytic zinc atom. In the CNAD complex, the pyridine nitrogen replaces alcohol as the fourth coordination ligand to the active site zinc atom, while all other polar interactions remain the same as those of bound NAD(H). The zinc-nitrogen ligand explains the high affinity of CNAD for LADH.

PubMed: 7918390
DOI: 10.1021/bi00205a009

Experimental method

X-RAY DIFFRACTION (2.7 Å)