| The research content in this paper contains two parts. The first part focuses on both theformation mechanism of alzhemer’s desease induced by metal ions coordination to the Aβpeptide(P) and the regulation mechanism of drugs(D) To address the topic, the structures ofCQ and its derivative drugs, metal ions, peptide chains, complexes formed by metal ions anddrugs or by metal ions and peptide chains, as well as by metal ions, drugs and peptide chainswere optimized. After that, binding energies between metal ions and drugs, between metalions and peptide chains and between metal and P+D complexes are calculated. Chargechanges on the copper ion in these complexes were analysed and following conclusions aredrawn. Two positive charges on the Cu2+will reduce and be close to+1when Cu2+iscombined with drugs or peptide chains. Binding energy results reveal that the binding strengthordering is Cu2+> Zn2+> Cu+in the complexes formed by peptide chains P10, P20, P22, P25and P27and metal ions Cu2+, Cu+and Zn2+. The ordering is also true both in the complexesformed by drugs CQ, CQ-1, CQ-2and CQ-3and the three metal ions, and in the combinationcomplexes of M-D and these different peptides. We use the binding energy of PM-CQcomlexes as standard to evaluate the effect of designed drugs CQ-1, CQ-2and CQ-3. Resultsshow that the effect of CQ-3on P-M complexes is the best, CQ-2second, and CQ-1third one.Analyses on the three kinds of substituent-H,-CL-NO2in these drugs reveal that the smallerthe electronegativity of the substituent is, the better the effect of the corresponding durgwould be. The information would be very helpful to the design of new drugs in the future fortreating alzheimer’s disease (AD).The second part discusses the adsorption and separation of Greenhouse gas CO2etc andpredicts several constitutions of biological adsorption materials. Due to the high speeddevelopment of modern industry, a large number of greenhouse gases were emitted into theatmosphere, leading to serious air pollution in cities. In these greenhouse gases, CO2playundoubtedly a key role. So how to separate and absorb CO2from other gases, such as H2andN2, becomes crucial. Zinc-adenine porous material was developed to separate and and absorbthese mixed gases by Rosi group recently.As an intriguing material building block for microporous metal-organic framework (MOF) materials, DNA base (pair) holds usually rigid-ring structures, multiple metalcoordination sites, biological compatibility, and molecular recognition and self-assemblingcharacteristics that could ultimately translate into interesting material properties. In thepresent paper, guanine G, cytosine C, adenine A and thymine T, and their pairs GC/AT as wellas their Zn2+complexes are selected as models to study their potential behavior of buildingblocks to adsorb and separate mixed small molecules H2, N2, CO2by employingM062X/6-31+G*method. The interaction modes and strengths as well as potential bindingsites are predicted. Results reveal CO2prefers to hydrogen bonding to the amino hydrogen(s)or/and imino hydrogen(s) of these bases (pairs), whereas both H2and N2prefer to beingadsorbed over the base ring with a-stacking interaction mode. A comparison for the bindingenergies of these different small molecules shows that AT is the more potential building blockthan GC and AA as MOF material, and would selectively adsorb these small moleculesaccording to the following order: H2<N2<CO2. The result offers theoretical predictions anddirection for the experimental selection in synthesis of such MOF materials built by thesedifferent base pair building blocks. |
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