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The low-barrier hydrogen bond in enzymic catalysis
2010Publisher Summary This chapter describes the various aspects of the low-barrier hydrogen bond in enzymic catalysis. Hydrogen bonds come in a continuum of bond lengths and strengths. The first examples of enzymatic reactions where low-barrier hydrogen bonds played a role involved enolization of the substrate to change the p K of a key group in the ...
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, 1997
Theoretical calculations in the gas phase on a series of intermolecular complexes formed between 1-methylimidazole (1-MeIm) and four carboxylic acids R−COOH, where R = CF3, CHCl2, C(CH3)Cl2, and CH2Cl, have been carried out.
M. Garcia-Viloca +2 more
semanticscholar +1 more source
Theoretical calculations in the gas phase on a series of intermolecular complexes formed between 1-methylimidazole (1-MeIm) and four carboxylic acids R−COOH, where R = CF3, CHCl2, C(CH3)Cl2, and CH2Cl, have been carried out.
M. Garcia-Viloca +2 more
semanticscholar +1 more source
On the Possibility of Using UV Spectroscopy as a Measure of the Low-Barrier Hydrogen Bond
Structural Chemistry, 2003In many enzyme-catalyzed biochemical pathways, a short, strong hydrogen bond between an enzyme and substrate is an important structural feature. These bonds are termed low-barrier hydrogen bonds. In this paper, we show that UV spectra can be used as an experimental technique to determine if a system contains a low-barrier hydrogen bond (LBHB).
Jeffrey E. Miller +3 more
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, 1997
It has been customary to accept that the observation of a highly deshielded proton is conclusive evidence that the molecule possesses a so-called low-barrier hydrogen bond (LBHB).
M. Garcia-Viloca +4 more
semanticscholar +1 more source
It has been customary to accept that the observation of a highly deshielded proton is conclusive evidence that the molecule possesses a so-called low-barrier hydrogen bond (LBHB).
M. Garcia-Viloca +4 more
semanticscholar +1 more source
Biochemistry, 1996
The N delta 1 proton of His 64 forms a hydrogen bond with Asp 32, as part of the catalytic triad in serine proteases of the subtilisin family. His 64 in subtilisin has been studied by 1H and 15N NMR spectroscopy in the presence and absence of peptidyl ...
C. J. Halkides +2 more
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The N delta 1 proton of His 64 forms a hydrogen bond with Asp 32, as part of the catalytic triad in serine proteases of the subtilisin family. His 64 in subtilisin has been studied by 1H and 15N NMR spectroscopy in the presence and absence of peptidyl ...
C. J. Halkides +2 more
semanticscholar +1 more source
Are There Really Low-Barrier Hydrogen Bonds in Proteins? The Case of Photoactive Yellow Protein
Journal of the American Chemical Society, 2014For a long time, low-barrier hydrogen bonds (LBHBs) have been proposed to exist in many enzymes and to play an important role in their catalytic function, but the proof of their existence has been elusive. The transient formation of an LBHB in a protein system has been detected for the first time using neutron diffraction techniques on a photoactive ...
José M. Lluch +3 more
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, 2013
The nuclear quantum effect on the short and asymmetric hydrogen bond of protonated lysine (LysH+) at room temperature is explored by ab initio path integral molecular dynamics (PIMD) simulation.
Yudai Ogata +3 more
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The nuclear quantum effect on the short and asymmetric hydrogen bond of protonated lysine (LysH+) at room temperature is explored by ab initio path integral molecular dynamics (PIMD) simulation.
Yudai Ogata +3 more
semanticscholar +1 more source
Characterization of a low barrier hydrogen bond in the active site of chymotrypsin
Journal of Molecular Structure, 2002Abstract The possibility of strong hydrogen bonding in aqueous solutions is supported by spectroscopic and chemical properties of proton sponges and internally strained dicarboxylic acid monoanions in aqueous and aqueous/acetone solutions. A species of low barrier hydrogen bond (LBHB) in aqueous solutions is the downfield proton in transition state ...
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Spectral Signatures of Proton-Transfer Dynamics at the Cusp of Low-Barrier Hydrogen Bonding
The Journal of Physical Chemistry Letters, 2018Despite their importance in diverse chemical and biochemical processes, low-barrier hydrogen bonds remain elusive targets to classify and interpret spectroscopically. Here the correlated nature of hydrogen bonding and proton transfer in the low-barrier regime has been probed for the ground and excited electronic states of 6-hydroxy-2-formylfulvene by ...
Zachary N. Vealey +2 more
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Low-Barrier Hydrogen Bond in the Catalytic Triad of Serine Enzymes
1998Acetylcholinesterase (AChE) and chymotrypsin are serine enzymes whose catalytic mechanism involves a nucleophilic attack (serine) and a general acid-base moiety (histidine). The incipient imidiazolium which is formed as a result of the nucleophilic attack by serine is stabilized by the negatively charged carboxylate (Glu or Asp).
Nathan A. Baker +4 more
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