3KFT

Crystal structure of Pentaerythritol Tetranitrate Reductase complex with 1,4,5,6-tetrahydro NADH

Summary for 3KFT

• Entry DOI: 10.2210/pdb3kft/pdb
• Descriptor: Pentaerythritol tetranitrate reductase, FLAVIN MONONUCLEOTIDE, NICOTINAMIDE-ADENINE-DINUCLEOTIDE, ... (4 entities in total)
• Functional Keywords: nadh:flavin oxidoreductase / nadh oxidase family, oxidoreductase
• Biological source: Enterobacter cloacae
• Total number of polymer chains: 2
• Total formula weight: 81047.54

Authors

Pudney, C.R.,Levy, C.W.,Leys, D.,Scrutton, N.S. (deposition date: 2009-10-28, release date: 2010-02-02, Last modification date: 2024-02-21)

Primary citation

Pudney, C.R.,Hay, S.,Levy, C.,Pang, J.,Sutcliffe, M.J.,Leys, D.,Scrutton, N.S.
Evidence to support the hypothesis that promoting vibrations enhance the rate of an enzyme catalyzed H-tunneling reaction.
J.Am.Chem.Soc., 131:17072-17073, 2009

PubMed Abstract: In recent years there has been a shift away from transition state theory models for H-transfer reactions. Models that incorporate tunneling as the mechanism of H-transfer are now recognized as a better description of such reactions. Central to many models of H-tunneling is the notion that specific vibrational modes of the protein and/or substrate can increase the probability of a H-tunneling reaction, modes that are termed promoting vibrations. Thus far there has been limited evidence that promoting vibrations can increase the rate of H-transfer. In the present communication we examine the single hydride transfer from both NADPH and NADH to FMN in the reductive half-reaction of pentaerythritol tetranitrate reductase (PETNR). We find that there is a significant promoting vibration with NADPH but not with NADH and that the observed rate of hydride transfer is significantly (approximately 15x) faster with NADPH. We rule out differences in rate due to variation in driving force and the donor-acceptor distance, suggesting it is the promoting vibration with NADPH that is the origin of the increased observed rate. This study therefore provides direct evidence that promoting vibrations can lead to an increase in rate.

PubMed: 19891489
DOI: 10.1021/ja908469m

Experimental method

X-RAY DIFFRACTION (2.1 Å)