Publication Date:
2006-04-15
Description:
We present an atomic-level description of the reaction chemistry of an enzyme-catalyzed reaction dominated by proton tunneling. By solving structures of reaction intermediates at near-atomic resolution, we have identified the reaction pathway for tryptamine oxidation by aromatic amine dehydrogenase. Combining experiment and computer simulation, we show proton transfer occurs predominantly to oxygen O2 of Asp(128)beta in a reaction dominated by tunneling over approximately 0.6 angstroms. The role of long-range coupled motions in promoting tunneling is controversial. We show that, in this enzyme system, tunneling is promoted by a short-range motion modulating proton-acceptor distance and no long-range coupled motion is required.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Masgrau, Laura -- Roujeinikova, Anna -- Johannissen, Linus O -- Hothi, Parvinder -- Basran, Jaswir -- Ranaghan, Kara E -- Mulholland, Adrian J -- Sutcliffe, Michael J -- Scrutton, Nigel S -- Leys, David -- New York, N.Y. -- Science. 2006 Apr 14;312(5771):237-41.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Manchester Interdisciplinary Biocentre, University of Manchester, Jackson's Mill, Post Office Box 88, Manchester M60 1QD, UK.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16614214" target="_blank"〉PubMed〈/a〉
Keywords:
Alcaligenes faecalis/*enzymology
;
Aspartic Acid/chemistry
;
Binding Sites
;
Catalysis
;
Chemistry, Physical
;
Computer Simulation
;
Crystallography, X-Ray
;
Kinetics
;
Models, Chemical
;
Motion
;
Oxidation-Reduction
;
Oxidoreductases Acting on CH-NH Group Donors/*chemistry/*metabolism
;
Oxygen/chemistry
;
Physicochemical Phenomena
;
*Protons
;
Temperature
;
Thermodynamics
;
Tryptamines/*metabolism
;
Water/chemistry
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
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