Section of the Watson-Crick DNA structure showing hydrogen bonds connecting the pyrimidine bases thymine (T) and cytosine (C) with, respectively, the purine bases adenine (A) and guanine (G). The precise hydrogen bond link between the bases made by Watson and Crick followed from the Chargraff base-pair rules and from J. O'Donohue's identification of the correct (keto) tautomeric form. Adapted with permission from Booth and Hey [6]. Copyright (1996) American Chemical Society.

Section of the Watson-Crick DNA structure showing hydrogen bonds connecting the pyrimidine bases thymine (T) and cytosine (C) with, respectively, the purine bases adenine (A) and guanine (G). The precise hydrogen bond link between the bases made by Watson and Crick followed from the Chargraff base-pair rules and from J. O'Donohue's identification of the correct (keto) tautomeric form. Adapted with permission from Booth and Hey [6]. Copyright (1996) American Chemical Society.

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We recall the experimental approaches involved in the discovery of hydrogen bonds in deoxyribonucleic acid (DNA) made 70 years ago by a team of scientists at University College Nottingham led by J.M. Gulland, and in relation to previous studies. This discovery proved an important step in the elucidation of the correct structure for DNA made by J.D....

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... Donohue, a Guggenheim Fellow sharing an office with them at the Cavendish -and an expert on tautometric forms -was able to point out to Watson that Davidson was wrong, and the T and G bases were primarily in the keto form (-CO-NH-) at physiological pH's [8]. This enabled Watson and Crick to complete their model, with the bases hydrogen bonded in their correct tautomeric forms (Figure 6), allowing a regular stacking of bases within the antiparallel double helical frame of the sugar-phosphate backbone and at the correct spacing. ...
Context 2
... Donohue, a Guggenheim Fellow sharing an office with them at the Cavendish -and an expert on tautometric forms -was able to point out to Watson that Davidson was wrong, and the T and G bases were primarily in the keto form (-CO-NH-) at physiological pH's [8]. This enabled Watson and Crick to complete their model, with the bases hydrogen bonded in their correct tautomeric forms (Figure 6), allowing a regular stacking of bases within the antiparallel double helical frame of the sugar-phosphate backbone and at the correct spacing. ...

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... For symmetric hydrogen bonds, two atoms of the same chemical element (e.g, halogen atoms) are bonded to the hydrogen atom with the same interatomic distance [3,4]. The classical hydrogen bonds are very important for biological systems including the protein synthesis and structure, the DNA structure, the enzyme-substrate interaction, and so on [5][6][7]. ...
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p>In previous work, we developed the local potential energy model, LPE, based on the electrostatic force and QTAIM topological data to quantify classical hydrogen bond energies. In this work, we extended the investigation to other inter/intramolecular interactions (non-conventional hydrogen bonds and others). The LPE presented high precision and linearity with supramolecular binding energy, when excluding interactions of an ion with π-bonded groups or polar molecule. The energy decomposition analysis from SAPT-DFT and LMOEDA showed that dispersion and electrostatic components are important to LPE, while polarization component impairs it. The LPE cannot be used for complexes with predominant polarization component. </p
... The HB is critical in the following cases: the folding and the final structure of the globular proteins [5]; the binding between substrate and enzyme [6]; the structure of the two strands of DNA helix; and the protein synthesis [6,7]. The HBs in -helical and -sheet model peptides were evaluated by the quantum theory of atoms in molecules, QTAIM [8], showing a linear relationship between topological data and energy of stabilization [9,10]. ...
Article
We developed the local potential energy, LPE, model based on the electrostatic force (the unique fundamental force for chemical bonds) whose equation uses QTAIM topological data. The effectiveness of the LPE was evaluated with other well-known methods (supramolecular binding enthapy, SAPT-DFT, LMOEDA and IQA) by analyzing the hydrogen bond energy for a set of organic and inorganic molecules. The LPE has the second highest linearity with the supramolecular binding enthalpy (R²=0.9808) and the highest precision (RMSD=1.60 kcal mol⁻¹). In addition, LPE has the advantage to give individual binding energy values when the complex has more than one hydrogen bond.
... For example, compounds 54 (Sulfoxaflor) (shown in Fig. 3) and 32 (Imidacloprid) contain N-N fragment at the topological distance 7 and their corresponding pLC 50 values are 0.053 and −1.029 respectively. Both intra and intermolecular hydrogen bonds exist in DNA (Harding et al., 2018). Presence of electronegative heteroatom like nitrogen may form hydrogen bond and electron donor acceptor (EDA) complex with the DNA of earthworm. ...
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