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Strong, Low-Barrier Hydrogen Bonds May Be Available to Enzymes [PDF]

open access: possibleBiochemistry, 2014
The debate over the possible role of strong, low-barrier hydrogen bonds in stabilizing reaction intermediates at enzyme active sites has taken place in the absence of an awareness of the upper limits to the strengths of low-barrier hydrogen bonds involving amino acid side chains. Hydrogen bonds exhibit their maximal strengths in isolation, i.e., in the
Kit H. Bowen   +4 more
openaire   +2 more sources
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Turning Low Barrier Hydrogen Bonds on and Off

Journal of the Chinese Chemical Society, 2010
AbstractThe hydrogen bond in the [HDihH‐Fda]+ ion (HDih: 4,5‐dihydro‐1H‐imidazole, Fda: 1‐fluoro‐N,N‐dimethylmethaneamine) can be an ordinary single well hydrogen bond (HB) or a low barrier hydrogen bond (LBHB) depending on the orientation of the CH2F group in the Fda molecule.
Chin-Hui Yu, Timm Lankau
openaire   +2 more sources

Proton Probability Distribution in the O···H···O Low-Barrier Hydrogen Bond: A Combined Solid-State NMR and Quantum Chemical Computational Study of Dibenzoylmethane and Curcumin.

Journal of Physical Chemistry B, 2016
We report a combined solid-state (1H, 2H, 13C, 17O) NMR and plane-wave density functional theory (DFT) computational study of the O···H···O low-barrier hydrogen bonds (LBHBs) in two 1,3-diketone compounds: dibenzoylmethane (1) and curcumin (2).
X. Kong   +7 more
semanticscholar   +1 more source

The strength of a low-barrier hydrogen bond in water

Tetrahedron Letters, 2002
Abstract There are large differences between the acidity of the enol of the acyclic diketone, 2,4-pentanedione and those of two cyclic diketones, 1,3-cyclopentanedione and 1,3-cyclohexanedione. Computational studies have demonstrated that these differences are largely due to the strength of the internal low-barrier hydrogen bond (LBHB) in the enol of
Freeman M. Wong   +2 more
openaire   +2 more sources

Low Barrier Hydrogen Bonds

Science, 1995
Proteins contain mainly weak, conventional hydrogen bonds; however, a few enzymes have low barrier hydrogen bonds (LBHBs) in transition state analog complexes. Hydrogen bonds display variations in physicochemical properties including length, spectroscopic characteristics, and strength.
openaire   +3 more sources

Low-Barrier Hydrogen Bonds and Enzymatic Catalysis

Archives of Biochemistry and Biophysics, 2000
Short, strong (low barrier) hydrogen bonds occur when the pK values of the atoms sharing the proton are similar. The overall distance is 2.5 A or less, the deuterium fractionation factor is less than 0.5, the proton NMR chemical shift can approach 20 ppm, and deuterium or tritium substitution causes an up-field change in the chemical shift.
openaire   +3 more sources

Absorption Wavelength Along Chromophore Low-Barrier Hydrogen Bonds

SSRN Electronic Journal, 2021
In low-barrier hydrogen bonds (H-bonds), the pKa values for the H-bond donor and acceptor moieties are nearly equal, whereas the redox potential values depend on the H+ position. Spectroscopic details of low-barrier H-bonds remain unclear. Here, we report the absorption wavelength along low-barrier H-bonds in protein environments, using a quantum ...
Keisuke Saito   +2 more
openaire   +2 more sources

Subangstrom crystallography reveals that short ionic hydrogen bonds, and not a His-Asp low-barrier hydrogen bond, stabilize the transition state in serine protease catalysis.

Journal of the American Chemical Society, 2006
To address questions regarding the mechanism of serine protease catalysis, we have solved two X-ray crystal structures of alpha-lytic protease (alphaLP) that mimic aspects of the transition states: alphaLP at pH 5 (0.82 A resolution) and alphaLP bound to
C. Fuhrmann, M. Daugherty, D. Agard
semanticscholar   +1 more source

On the Possibility of Detecting Low Barrier Hydrogen Bonds with Kinetic Measurements

Journal of Chemical Information and Computer Sciences, 2003
Recent experimental evidence has pointed to the possible presence of a short, strong hydrogen bond in the enzyme-substrate transition states in some biochemical reactions. To date, most experimental measures of these short, strong hydrogen bonds have monitored their equilibrium properties. In this work we show that kinetic measurements can also be used
Michael Messina   +3 more
openaire   +3 more sources

Follow the protons: a low-barrier hydrogen bond unifies the mechanisms of the aspartic proteases.

Accounts of Chemical Research, 2001
Seven proton transfers in five steps participate in a catalytic turnover of an aspartic protease. The Rosetta Stone for elucidating their role is a low-barrier hydrogen bond that holds the two aspartic carboxyls in a coplanar conformation.
D. Northrop
semanticscholar   +1 more source

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