D-aminoácidos em biologia: mais do que se julga

Silva, João J. R. Fraústo da; Silva, José Armando L. da

doi:10.1590/s0100-40422009000200046

Cited by 7 publications

(11 citation statements)

References 52 publications

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“…Sure, these are the foundations of the quantum theory of atoms in molecules (QTAIM), [ 95 ] which has been used in routine studies of intermolecular systems, mainly those weakly bound ones. [ 96–99 ] Historically, the F···H, O···H, and N···H hydrogen bonds [ 22,23,35,100 ] with energies of 30 KJ.mol −1 as well as the π···H and pseudo‐π···H as the weaker ones, all of them have been characterized on the basis of the QTAIM formalism. The modeling of the hydrogen bonds in the C 3 H 6 , C 4 H 8 , C 6 H 6 , and C 8 H 8 alkanes summarizes the cornerstone of this current work if, specially, beyond an atom, a chemical bond, or even a triangular or square faces of the rings, can function as nucleophiles to interact with hydrogen donors.…”

Section: Computational Approaches and Quantum Electronic Structure Mementioning

confidence: 99%

“…[ 13 ] Regardless, the capability of the hydrocarbons to form intermolecular interaction must be increasingly explored, although this theme has been discussed in studies published along the last decade, [ 14–22 ] by which the existence of hydrogen bonds with properties never seen before has been revealed. [ 23,24 ] In a brief comment, it should be emphasized that the hydrogen bond model framed as Y···H–X is universal, [ 25–29 ] even so some restrictions must be considered on the basis of elementary criteria; eg, the electronegativity values of Y and X should be higher in comparison to the hydrogen. [ 21 ]…”

Section: Introductionmentioning

confidence: 99%

“…[ 55 ] These cyclic and cubic alkanes represent a high‐level challenge in the field of intermolecular interactions formed with standard molecular acids. [ 56 ] By assuming that C 3 H 6 and C 4 H 8 can be suitable structures to form hydrogen bonds, such as the pseudo‐π···H–X [ 37 ] instead of the π···H–X type, [ 22,23 ] and in this insight, the great goal of this current research is definitively established.…”

Section: Introductionmentioning

confidence: 99%

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The definitive challenge of forming uncommon pseudo‐π···H–F and C···H–F hydrogen bonds on cyclic and cubic nonpolar hydrocarbons

Santos

Carvalho

Oliveira

et al. 2020

J of Physical Organic Chem

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Due to the high symmetry and low polarity of the cyclopropane (C 3 H 6), cyclobutane (C 4 H 8), prismane (C 6 H 6), and cubane (C 8 H 8), it is widely known that these structures unlikely act as proton receptors to form intermolecular interactions with monoprotic acids, such as the hydrogen fluoride. Although the C 3 H 6 ÁÁÁHF, C 4 H 8 ÁÁÁHF, C 6 H 6 ÁÁÁHF, and C 8 H 8 ÁÁÁHF are weakly bound complexes, in this current work, all of them were definitively certified on the basis of a theoretical analysis. In according with the structural parameters and spectroscopy modes appraised through the density-functional theory calculations, the more accentuated perturbations are manifested in the hydrogen fluoride. The new hydrogen bond forms framed as pseudo-πÁÁÁH and CÁÁÁH were unveiled through the calculations of the quantum theory of atoms in molecules and natural bond orbital. In this context, the knowledge about the nature of these hydrogen bonds is necessary, wherein it used the symmetry-adapted perturbation theory for computing the contributions of the electrostatic, polarization, exchange, dispersion, and charge transfer terms. Lastly, the practical behavior of these hydrocarbons under the condition to form intermolecular interactions was examined by taking into account the solvent effect with calculations of the polarizable continuum model.

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Section: Computational Approaches and Quantum Electronic Structure Mementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The definitive challenge of forming uncommon pseudo‐π···H–F and C···H–F hydrogen bonds on cyclic and cubic nonpolar hydrocarbons

Santos

Carvalho

Oliveira

et al. 2020

J of Physical Organic Chem

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“…-Information on the occurrence of d-amino acids in vivo have been already compiled by several authors [4] [5] [8] [12]. Once the basic notions on the natural occurrence of d-amino acids in nature have been recognized, the question is how important they are for living systems.…”

mentioning

confidence: 99%

“…Once the basic notions on the natural occurrence of d-amino acids in nature have been recognized, the question is how important they are for living systems. Here, the idea proposed by da Silva and da Silva [12] on the natural sequence followed in the evolutionary process by Scheme. General Scheme for Base-(a) and Acid-Catalyzed (b) Racemization of Amino Acids The best described and understood use of d-amino acids might be their involvement in the formation of the peptidoglycan of eubacteria (Fig.…”

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confidence: 99%

Natural Occurrence and Industrial Applications of d‐Amino Acids: An Overview

Martínez‐Rodríguez

Martínez-Gómez

Rodríguez‐Vico

et al. 2010

Chemistry & Biodiversity

114

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Interest in D-amino acids has increased in recent decades with the development of new analytical methods highlighting their presence in all kingdoms of life. Their involvement in physiological functions, and the presence of metabolic routes for their synthesis and degradation have been shown. Furthermore, D-amino acids are gaining considerable importance in the pharmaceutical industry. The immense amount of information scattered throughout the literature makes it difficult to achieve a general overview of their applications. This review summarizes the state-of-the-art on D-amino acid applications and occurrence, providing both established and neophyte researchers with a comprehensive introduction to this topic.

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Origin, Microbiology, Nutrition, and Pharmacology of D‐Amino Acids

Friedman

2010

Chemistry & Biodiversity

156

108

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Exposure of food proteins to certain processing conditions induces two major chemical changes: racemization of all L-amino acids (LAAs) to D-amino acids (DAAs) and concurrent formation of cross-linked amino acids such as lysinoalanine (LAL). The diet contains both processing-induced and naturally-formed DAA. The latter include those found in microorganisms, plants, and marine invertebrates. Racemization impairs digestibility and nutritional quality. Racemization of LAA residues to their D-isomers in food and other proteins is pH-, time-, and temperature-dependent. Although racemization rates of LAA residues in a protein vary, relative rates in different proteins are similar. The nutritional utilization of different DAAs varies widely in animals and humans. Some DAAs may exert both adverse and beneficial biological effects. Thus, although D-Phe is utilized as a nutritional source of L-Phe, high concentrations of D-Tyr in such diets inhibit the growth of mice. Both D-Ser and LAL induce histological changes in the rat kidney. The wide variation in the utilization of DAAs is illustrated by the fact that, whereas D-Meth is largely utilized as a nutritional source of the L-isomer, D-Lys is not. Similarly, although L-CysSH has a sparing effect on L-Meth when fed to mice, D-CysSH does not. Since DAAs are consumed as part of their normal diet, a need exists to develop a better understanding of their roles in foods, microbiology, nutrition, and medicine. To contribute to this effort, this overview surveys our present knowledge of the chemistry, nutrition, safety, microbiology, and pharmacology of DAAs. Also covered are the origin and distribution of DAAs in food and possible roles of DAAs in human physiology, aging, and the etiology and therapy of human diseases.

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D-aminoácidos em biologia: mais do que se julga

Abstract: D-aminoáciDos em biologia-mais Do que se julga joão j. R. Fraústo da silva * e josé armando l. da silva

Cited by 7 publications

References 52 publications

The definitive challenge of forming uncommon pseudo‐π···H–F and C···H–F hydrogen bonds on cyclic and cubic nonpolar hydrocarbons

The definitive challenge of forming uncommon pseudo‐π···H–F and C···H–F hydrogen bonds on cyclic and cubic nonpolar hydrocarbons

Natural Occurrence and Industrial Applications of d‐Amino Acids: An Overview

Origin, Microbiology, Nutrition, and Pharmacology of D‐Amino Acids

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