In the present study, experimentally observed inhibition mechanism of zinc enzyme carbonic anhydrase XII (CA XII) by new class of suicide inhibitors, glycosyl coumarin, has been modeled using of density functional theory (DFT) to investigte the geometrical parameters and thermocemical aspects of this mechanism in the solution phase. In the first step of this research the most stable conformer of four 7-substituted sugar coumarin including galactose, mannose, ribose and glucose derivatives as more effective and coumarin as the less effective inhibitor of CA XII respectively has been search and interact with CA XII active site. The results of our calculations indicate that all above mentioned inhibitors do not directly interact with the metal ion from the CA active center. Moreover, the calculated thermodynamic function values indicate the presence of sugar moiety in the coumarin molecule was associated with more effective inhibition. Furthermore, interactions between the most stable conformer of galactose derivative as the best inhibitors with CA XII in presence of water solvent were studied by employing explicit solvent model. In addition the good agreements between our calculated results with experimental data indicate a reliable agreement of method of calculations.

Recently, it has been suggested that ion channel selectivity filter may exhibit quantum coherence, which may be appropriate to explain ion selection and conduction processes. Potassium channels play a vital role in many physiological processes. One of their main physiological functions is the efficient and highly selective transfer of K+ ions through the membranes into the cells. To do this, ion channels must be highly selective, allowing only certain ions to pass through the membrane, while preventing the others. The present research is an attempt to investigate the relationship between hopping rate and maintaining coherence in ion channels. Using the Lindblad equation to describe a three-level system, the results in different quantum regimes are examined. We studied the distillable coherence and the second order coherence function of the system. The oscillation of distillable coherence from zero, after the decoherence time, and also the behavior of the coherence function clearly show the point that the system is coherent in ion channels with high throughput rates.

Recently, it has been suggested that ion channel selectivity filter may exhibit quantum coherence, which may be appropriate to explain ion selection and conduction processes. Potassium channels play a vital role in many physiological processes. One of their main physiological functions is the efficient and highly selective transfer of K + ions through the membranes into the cells. To do this, ion channels must be highly selective, allowing only certain ions to pass through the membrane, while preventing the others. The present research is an attempt to investigate the relationship between hopping rate and maintaining coherence in ion channels. Using the Lindblad equation to describe a three-level system, the results in different quantum regimes are examined. We studied the distillable coherence and the second order coherence function of the system. The oscillation of distillable coherence from zero, after the decoherence time, and also the behavior of the coherence function clearly show the point that the system is coherent in ion channels with high throughput rates.

Carbonic anhydrase is an enzyme which has the zinc as the metallic part of it. This enzyme catalyzes the reversible reaction of turning carbon dioxide into bicarbonate. In this research the mechanism of inhibition a new class of inhibitor of this enzyme, glycosyl coumarin has been modeled using the density functional theory (DFT). First, the most constant confirmer of this four coumarin sugar derivatives which includes galactose, mannose, ribose and glucose has been selected and then they had been interacted as inhibitor with CA (II) enzyme's active site. In further for showing the effect of sugar in these molecules, coumarin itself had been chosen as inhibitor and the inhibitory effect is surveyed. All calculations have been done by density functional theory in level of B3LYP with basic set 6-31G* and with Minnesota function M06 with basic set 6-31+G*. Thermodynamic functions like enthalpy of formation, entropy of formation and Gibbs free energy for CA-inhibitor have been computed. The results indicate that the reaction among these groups of inhibitors and Carbonic anhydrase is not of the type of direct and syndetic but the enzyme is deactivated with space effect and addition to this, the computed thermodynamic functions show that although this coumarin sugar derives have deterrence in the range of micro molar but, coumarin without sugar is a stronger deterrence for CA II. Finally, the interaction between the most constant confirmer (galactose coumarin) is surveyed as the best deterrence using the explicit solvent method.

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