Russian Journal of Biological Physics and Chemisrty Russian Journal of Biological Physics and Chemisrty АКТУАЛЬНЫЕ ВОПРОСЫ БИОЛОГИЧЕСКОЙ ФИЗИКИ И ХИМИИ 2499-9962 83232 10.29039/rusjbpc.2023.0603 МОДЕЛИРОВАНИЕ В БИОФИЗИКЕ И БИОИНФОРМАТИКА MODELLING IN BIOPHYCIS AND BIOINFORMATISC МОДЕЛИРОВАНИЕ В БИОФИЗИКЕ И БИОИНФОРМАТИКА THEORETICAL STUDY OF THE CARNOSINE N1H TAUTOMER IN THE ZWITTERIONIC FORM ТЕОРЕТИЧЕСКОЕ ИССЛЕДОВАНИЕ N1H ТАУТОМЕРА КАРНОЗИНА В ЦВИТТЕРИОННОЙ ФОРМЕ Демухамедова С. Д. Demukhamedova S. D. svetlanabest@mail.ru Ахвердиева Г. А. Akverdieva G. A. hagverdigulnara@gmail.com Бакинский государственный университет Баку Азербайджан Baku State University Baku Azerbaijan Бакинский государственный университет Баку Азербайджан Baku State University Baku Azerbaijan 21 05 2024 21 05 2024 8 2 159 168 16 07 2023 https://rusjbpc.ru/en/nauka/article/83232/view

В представленной работе исследовано пространственное и электронное строение наиболее низкоэнергетической конформации N1H таутомера карнозина в цвиттерионной форме, имеющего широкий спектр применения. Расчеты проводились квантовохимическим методом DFT на основе гибридного функционала B3LYP и базисного набора 6-31+G(d,p) в газе, воде и в ДМСО с использованием программ Gaussian 09 и GaussView 6.0.16. Вычислены геометрические параметры, значения электронной энергии, дипольные моменты, величины парциальных зарядов на атомах, энергии HOMO и LUMO орбиталей, дескрипторы реакционной способности молекулы и проведен NBO анализ. Визуализированы карты молекулярного электростатического потенциала (МЕР) и граничные орбитали, Проанализированы структурные и электронные перестройки в молекуле и изменения различных параметров в зависимости от диэлектрической проницаемости среды. Выявлено, что влияние растворителя не играет существенной роли для данной структуры, получены очень похожие результаты для водной среды и ДМСО. Однако в газовой фазе оптимизация геометрии данного таутомера цвиттериона карнозина привела к отщеплению атома водорода от концевой группы NH3+ и присоединению его к группе СОО-, фактически преобразовав цвиттерионную форму в нейтральную.

. In the present work, the spatial and electronic structures of the lowest energy conformation of the carnosine N1H tautomer in the zwitterionic form, which has a wide range of applications, have been studied. The calculations were performed by the DFT quantum-chemical method based on the B3LYP hybrid functional and the 6-31+G(d,p) basis set in gas, water, and DMSO using the Gaussian 09 and GaussView 6.0.16 programs. The geometry parameters, values of electronic energy, dipole moments, values of partial charges on atoms, HOMO and LUMO energies, descriptors of reactivity of a molecule were calculated and NBO analysis is carried out. The molecular electrostatic potential (MEP) maps and frontier orbitals were visualized. The structural and electronic rearrangements in the molecule and changes in various parameters depending on the dielectric constant of the medium were analyzed. It was found that the influence of the solvent does not play a significant role for this structure, very similar results were obtained for the aqueous medium and DMSO. However, the optimization of the geometry of this carnosine zwitterion tautomer in the gas phase, led to the elimination of the hydrogen atom from the terminal NH3+ group and its addition to the COO- group, actually converting the zwitterionic form into a neutral one.

 цвиттерион карнозина структура глобальные дескрипторы реактивности NBO анализ ИК спектры carnosine zwitterion structure global reactivity descriptors NBO analysis IR spectra

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