13C- and 15N-NMR studies of the reaction of aromatic amine dehydrogenase (AADH) with methylamine demonstrated that the products of the reductive half-reaction are an equivalent of formaldehyde hydrate and a reduced aminoquinol form of the tryptophan tryptophylquinone (TTQ) cofactor which contains covalently bound substrate-derived N. These data are consistent with the Ping Pong kinetic mechanism and aminotransferase-type chemical reaction mechanism which have been previously proposed for AADH. Comparison of the 15N-NMR spectra of the aminoquinol TTQ intermediates of AADH and methylamine dehydrogenase (MADH) revealed that the substrate-derived aminoquinol N of AADH and MADH exhibited distinct 15N chemical shifts which are separated by approx. 7 p.p.m. In each case, the signal for the substrate-derived aminoquinol N appears optimally with short pulse delay and exhibits a relaxation time and chemical shift which are consistent with 15N covalently bound to an aromatic ring (i.e. aminoquinol) which is attached to a rigid protein matrix. The aminoquinol of AADH is less stable against reoxidation than that of MADH. These data suggest that differences in the active-site mediated electrostatic environments of the aminoquinol N in the respective enzymes may influence both the observed 15N chemical shift and the relative reactivities of the TTQ aminoquinols towards oxygen. These data also demonstrate the utility of 13C- and 15N-NMR spectroscopy as a tool for monitoring the intermediates and products of enzyme-catalysed transformations.
Identification of Cryptic Products of the Gliotoxin Gene Cluster Using NMR-Based Comparative Metabolomics and a Model for Gliotoxin Biosynthesis
Identification of Cryptic Products of the Gliotoxin Gene Cluster Using NMR-Based Comparative Metabolomics and a Model for Gliotoxin Biosynthesis
Ry R. Forseth, Ellen M. Fox, DaWoon Chung, Barbara J. Howlett, Nancy P. Keller and Frank C. Schroeder
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja2029987/aop/images/medium/ja-2011-029987_0004.gif
Journal of the American Chemical Society
DOI: 10.1021/ja2029987
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA
http://feeds.feedburner.com/~r/acs/jacsat/~4/kET0fe1YTXQ
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06-07-2011 01:01 AM
[NMR paper] Interaction of the E2 and E3 components of the pyruvate dehydrogenase multienzyme com
Interaction of the E2 and E3 components of the pyruvate dehydrogenase multienzyme complex of Bacillus stearothermophilus. Use of a truncated protein domain in NMR spectroscopy.
Related Articles Interaction of the E2 and E3 components of the pyruvate dehydrogenase multienzyme complex of Bacillus stearothermophilus. Use of a truncated protein domain in NMR spectroscopy.
FEBS J. 2005 Jan;272(1):259-68
Authors: Allen MD, Broadhurst RW, Solomon RG, Perham RN
A (15)N-labelled peripheral-subunit binding domain (PSBD) of the dihydrolipoyl...
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11-24-2010 11:14 PM
[NMR paper] Low-populated folding intermediates of Fyn SH3 characterized by relaxation dispersion
Low-populated folding intermediates of Fyn SH3 characterized by relaxation dispersion NMR.
Related Articles Low-populated folding intermediates of Fyn SH3 characterized by relaxation dispersion NMR.
Nature. 2004 Jul 29;430(6999):586-90
Authors: Korzhnev DM, Salvatella X, Vendruscolo M, Di Nardo AA, Davidson AR, Dobson CM, Kay LE
Many biochemical processes proceed through the formation of functionally significant intermediates. Although the identification and characterization of such species can provide vital clues about the mechanisms of the...
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11-24-2010 09:51 PM
Insights into the Mechanism of Ligand Binding to Octopine Dehydrogenase from Pecten m
Insights into the Mechanism of Ligand Binding to Octopine Dehydrogenase from Pecten maximus by NMR and Crystallography.
Related Articles Insights into the Mechanism of Ligand Binding to Octopine Dehydrogenase from Pecten maximus by NMR and Crystallography.
PLoS One. 2010;5(8):
Authors: Smits SH, Meyer T, Mueller A, van Os N, Stoldt M, Willbold D, Schmitt L, Grieshaber MK
Octopine dehydrogenase (OcDH) from the adductor muscle of the great scallop, Pecten maximus, catalyzes the NADH dependent, reductive condensation of L-arginine and pyruvate to...
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09-03-2010 02:30 PM
[NMR paper] C-NMR study on the interaction of medium-chain acyl-CoA dehydrogenase with acetoacety
C-NMR study on the interaction of medium-chain acyl-CoA dehydrogenase with acetoacetyl-CoA.
Related Articles C-NMR study on the interaction of medium-chain acyl-CoA dehydrogenase with acetoacetyl-CoA.
J Biochem. 1996 Mar;119(3):512-9
Authors: Miura R, Nishina Y, Fuji S, Shiga K
The change-transfer interaction in the complex of pig kidney medium-chain acyl-CoA dehydrogenase (MCAD) with acetoacetyl-CoA was investigated by 13C-NMR spectroscopy and molecular orbital treatment. The acyl carbons of acetoacetyl-CoA were separately 13C-labeled and...
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08-22-2010 02:27 PM
[NMR paper] A 19F-NMR study of the membrane-binding region of D-lactate dehydrogenase of Escheric
A 19F-NMR study of the membrane-binding region of D-lactate dehydrogenase of Escherichia coli.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www3.interscience.wiley.com-aboutus-images-wiley_interscience_pubmed_logo_FREE_120x27.gif http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles A 19F-NMR study of the membrane-binding region of D-lactate dehydrogenase of Escherichia coli.
Protein Sci. 1993 Nov;2(11):1938-47
Authors: Sun ZY, Truong HT, Pratt EA, Sutherland DC,...
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08-22-2010 03:01 AM
[NMR software blog] Natural Products
Natural Products
http://1.bp.blogspot.com/_ROkYShLRKqA/SteNWieFqCI/AAAAAAAAARk/qKuAY5zIiGo/s400/antiphase.png
A reader asked me: "What is the shape of a 2-D peak?" and my answer was: "Exponential! (in time domain)". This is all you need to know, I think. The picture should help, as always. If you are reading this blog, it means that you have something like a computer. Even the iPhone is a computer (you can run programs on it) and can display my blog. I suspect, however, that you have a better computer, like I do.
You can use your computer to run simulations and more: you can ask it to...
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08-21-2010 06:29 PM
How can NMR be used to differentiate between the 2 nitration products?
How can NMR be used to tell the difference between the major and minor product of nitration of 4-methylacetanilide?4-methylacetanilide ------HNO3----> major + minor pdtsPlease explain how you know where the chemical shifts are and what are the names of the final pdts? Thank you very much!
Identification of reaction products and intermediates of aromatic-amine dehydrogenase
Linear Mode
