Theoretical Exploring of a Molecular Mechanism for Melanin Inhibitory Activity of Calycosin in Zebrafish.

Tyrosinase is an oxidase that is the rate-limiting enzyme for controlling the production of melanin in the human body. Overproduction of melanin can lead to a variety of skin disorders. Calycosin is an isoflavone from Astragali Radix, which is a traditional Chinese medicine that exhibits several pharmacological activities including skin whitening.

3D-QSAR, molecular docking, and molecular dynamics simulation of a novel thieno[3,4-d]pyrimidine inhibitor targeting human immunodeficiency virus type 1 reverse transcriptase.

Human immunodeficiency virus type 1 reverse transcriptase (HIV-1 RT) is one of the most attractive drug targets for the treatment of AIDS. In this study, 67 thieno[3,4-d]pyrimidine derivatives were selected as novel HIV-1 RT inhibitors to combat viral resistance, and were subjected to 3 D-QSAR studies using CoMFA, CoMSIA, and T-CoMFA. In the 3 D-QSAR study, two methods of ligand-based alignment and pharmacophore-based alignment were used.

Structural insight into the serotonin (5-HT) receptor family by molecular docking, molecular dynamics simulation and systems pharmacology analysis.

Serotonin (5-HT) receptors are proteins involved in various neurological and biological processes, such as aggression, anxiety, appetite, cognition, learning, memory, mood, sleep, and thermoregulation. They are commonly associated with drug abuse and addiction due to their importance as targets for various pharmaceutical and recreational drugs. However, due to a high sequence similarity/identity among 5-HT receptors and the unavailability of the 3D structure of the different 5-HT receptor, no report was available so far regarding the systematical comparison of the key and selective residues involved in the binding pocket, making it difficult to design subtype-selective serotonergic drugs.

A convenient four-component one-pot synthesis of 2-amino-1,3,4-thiadiazoles in water.

A novel four-component one-pot approach for the synthesis of 2-amino-1,3,4-thiadiazoles from primary amines, carbon disulfide, hydrazine, and acyl chlorides has been developed. A series of 5-substituted-2-amino-1,3,4-thiadiazoles were synthesized in medium-to-good yields utilizing this newly developed method.

A facile in situ synthesis route for CuInS(2) quantum-dots/In(2)S(3) co-sensitized photoanodes with high photoelectric performance.

CuInS2 quantum-dot sensitized TiO2 photoanodes with In2S3 buffer layer were in situ prepared via chemical bath deposition of In2S3, where the Cd-free In2S3 layer then reacted with TiO2/CuxS which employed a facile SILAR process to deposit CuxS quantum dots on TiO2 film, followed by a covering process with ZnS layer. Polysulfide electrolyte and Cu2S on FTO glass counter electrode were used to provide higher photovoltaic performance of the constructed devices. The characteristics of the quantum dots sensitized solar cells were studied in more detail by optical measurements, photocurrent-voltage performance measurements, and impedance spectroscopy.

QSAR study on MHC class I a alleles based on the novel parameters of amino acids.

MHC-epitope binding plays a key role in the cellular immune response. Accurate prediction of MHC-epitope binding affinity can greatly expedite epitope screening by reducing costs and experimental effort. In this paper, 13 T descriptors， which derived from 544 physicochemical properties of the natural amino acids, were used to characterize 4 MHC class I alleles epitope peptide sequences, the optimal QSAR models were constructed by using stepwise regression combines with multiple linear regression (STR-MLR).

Quantitative sequence-kinetics relationship in antigen-antibody interaction kinetics based on a set of descriptors [corrected].

The interaction between recombinant Fab57P and the coat protein of tobacco mosaic virus was studied using quantitative structure-activity relationship (QSAR) method. The development of quantitative multivariate model has shown to be a promising approach for unraveling protein-protein interactions by designed mutations in peptide sequence. This approach makes it possible to stereo-chemically determine which residue properties contribute most to the interaction.

New descriptors of amino acids and their application to peptide QSAR study.

A new set of descriptors was derived from a matrix of three structural variables of the natural amino acid, including van der Waal's volume, net charge index and hydrophobic parameter of side residues. They were selected from many properties of amino acid residues, which have been validated being the key factors to influence the interaction between peptides and its protein receptor. They were then applied to structure characterization and QSAR analysis on bitter tasting di-peptide, agiotensin-converting enzyme inhibitor and bactericidal peptides by using multiple linear regression (MLR) method.