Results 161 to 170 of about 240,874 (239)

Low-Barrier Hydrogen Bonds and Enzymic Catalysis

Science, 1994
Formation of a short (less than 2.5 angstroms), very strong, low-barrier hydrogen bond in the transition state, or in an enzyme-intermediate complex, can be an important contribution to enzymic catalysis. Formation of such a bond can supply 10 to 20 kilocalories per mole and thus facilitate difficult reactions such as enolization of ...
W W, Cleland, M M, Kreevoy
openaire   +2 more sources

The low barrier hydrogen bond (LBHB) proposal revisited: The case of the Asp ··· His pair in serine proteases

Proteins: Structure, Function, and Bioinformatics, 2004
Claudia Schütz, Arieh Warshel
openalex   +2 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. The proton of this bond shuttles between oxygens during chemical steps via hydrogen tunneling, unlike in previous ...
D. Northrop
semanticscholar   +3 more sources

Low-barrier hydrogen bonds in proteins

Crystallography Reviews, 2013
Hydrogen bonding interactions are one of the most important chemical interactions among materials, especially biological materials, which help confer specificity, which is crucial for their efficient functioning. Recently, low-barrier hydrogen bonds (LBHBs) have been proposed to play a critical role in enzyme catalysis.
M. V. Hosur, R. Chitra, Samarth Hegde, R. R. Choudhury, Amit Das, R. V. Hosur   +5 more
openaire   +1 more source

Energetics of a Low Barrier Hydrogen Bond in Nonpolar Solvents

Journal of the American Chemical Society, 1996
A measure of the strength of a low barrier hydrogen bond (LBHB) in apolar organic media was obtained using synthetic molecules derived from Kemp's triacid. The structures feature unusually rigid conformations that enforce intramolecular hydrogen bonds in a dicarboxylic acid, its corresponding acid-amide and their respective conjugate bases. Analysis of
Y. Kato, A. Toledo, J. Rebek
semanticscholar   +2 more sources

The Deuterium Isotope Effect on the NMR Signal of the Low-Barrier Hydrogen Bond in a Transition- State Analog Complex of Chymotrypsin

Biochemical and Biophysical Research Communications - BBRC, 2000
Constance S. Cassidy, Jing Lin, Perry A. Frey   +2 more
openalex   +2 more sources

Transient low-barrier hydrogen bond in the photoactive state of green fluorescent protein.

Physical Chemistry Chemical Physics, 2015
A transient low-barrier hydrogen bond has been found directly after photoexcitation using quantum dynamics to study the excited-state process in GFP.
Marc Nadal-Ferret, Ricard Gelabert, M. Moreno, J. M. Lluch   +3 more
semanticscholar   +3 more sources

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.
Timm Lankau, Chin‐Hui Yu
openaire   +1 more source

Theoretical Study of the Low-Barrier Hydrogen Bond in the Hydrogen Maleate Anion in the Gas Phase. Comparison with Normal Hydrogen Bonds

Journal of the American Chemical Society, 1997
Relative strengths of normal and low-barrier hydrogen bonds (LBHBs) in the gas phase were analyzed by means of quantum-mechanical and thermodynamic calculations on the mesaconic/citraconic and several maleic/fumaric cis/trans isomerization equilibria. All geometries were fully optimized with correlation effects included via second-order Moller−Plesset ...
M. Garcia-Viloca, A. González-Lafont, J. M. Lluch   +2 more
semanticscholar   +2 more sources

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, James R Keeffe, Weiming Wu   +2 more
openaire   +1 more source