Although the sequence information on G-protein coupled receptors (GPCRs) continues to grow, many GPCRs remain orphaned (i.e. ligand specificity unknown) or poorly characterized with little structural information available, so an automated and reliable method is badly needed to facilitate the identification of novel receptors. In this study, a method of fast Fourier transform-based support vector machine has been developed for predicting GPCR subfamilies according to protein's hydrophobicity. In classifying Class B, C, D and F subfamilies, the method achieved an overall Matthew's correlation coefficient and accuracy of 0.95 and 93.3%, respectively, when evaluated using the jackknife test. The method achieved an accuracy of 100% on the Class B independent dataset. The results show that this method can classify GPCR subfamilies as well as their functional classification with high accuracy. A web server implementing the prediction is available at http://chem.scu.edu.cn/blast/Pred-GPCR.

In this paper the embedded zerotree wavelet (EZW) method and Huffman coding are proposed to compress infrared (IR) spectra. We found that this technique is much better than thers in terms of efficiently coding wavelet coefficients because the zerotree quantization is an effective way of exploiting the self-similarities of wavelet coefficients at various resolutions.

This paper applies discrete wavelet transform (DWT) with various protein substitution models to find functional similarity of proteins with low identity. A new metric, 'S' function, based on the DWT is proposed to measure the pair-wise similarity. We also develop a segmentation technique, combined with DWT, to handle long protein sequences. The results are compared with those using the pair-wise alignment and PSI-BLAST.

Studies of the ultraviolet spectra and ab initio calculations have been carried out for vitamin E, p-benzoquinone and their complex in the present work. Steady-state absorption spectra have been experimentally measured with a Shimadzu UV-2100S spectrometer at room temperature. Measured values of maximum absorptions of vitamin E and p-benzoquinone in methanol are in excellent agreement with those reported in reference. In theoretical calculations, face-to-face conformations of the electron donor-acceptor (EDA) complex have been selected. The geometries of EDA complexes have been determined by searching for the energy minimum through the variation of the center to center distance between the isolated optimized geometries of the donor and the acceptor. The electronically excited states have been investigated by means of complete active space self-consistent field method associated with 6-31G* basis sets. The state optimizations of S0 and S1 for EDA complex reveal that the photoexcitation can directly yield an excited charge transfer (CT) state, and the CT absorption arises from the electron transition between two p-type molecular obitals. Based on the approximations of spherical cavity and point dipole, CT absorption in methanol has been investigated by considering the solvent reorganization energy correction.

In this paper, a new hybrid model of amino acid substitution is developed and compared with the others in previous works. The results show that the new hybrid model can characterize the protein sequences very well by calculating Fisher weights, which can denote how much the variants contribute to the classification.