Protein protein recognition is an important step in biological processes, which still largely remains elusive. The inter residue contact potential, CP ij , describes the propensity of contact between two type...Protein protein recognition is an important step in biological processes, which still largely remains elusive. The inter residue contact potential, CP ij , describes the propensity of contact between two types of residue. In this study, several different CP ij variants were examined with the objective of discriminating the binding potential of surface pairs. Using solvent mediated inter molecule contact potential (SM IMCP ij ), an evaluation model was deduced and tested. Using the evaluation model it was found that the SM IMCP ij gives a better performance than either residue mediated IMCP ij (RM IMCP ij ) or folding residue contact potential (FCP ij ). The results suggest that the evaluation model provides a fast, effective, and discriminative method for the evaluation of proposed binding interfaces.展开更多
Surface glycosylation of polymeric membranes has been inspired by the structure of natural biomem-branes. It refers to that glycosyl groups are introduced onto the membrane surface by various strate-gies, which combin...Surface glycosylation of polymeric membranes has been inspired by the structure of natural biomem-branes. It refers to that glycosyl groups are introduced onto the membrane surface by various strate-gies, which combine the separation function of the membrane with the biological function of the sac-charides in one system. In this review, progress in the surface glycosylation of polymeric membranes is highlighted in two aspects, i.e. the glycosylation methods and the potential applications of the sur-face-glycosylated membranes.展开更多
Cell-cell recognition is the key for multicellular organisms to survive. This recognition critically depends on protein-protein interactions from opposing cell surfaces. Recent structural investigations reveal unique ...Cell-cell recognition is the key for multicellular organisms to survive. This recognition critically depends on protein-protein interactions from opposing cell surfaces. Recent structural investigations reveal unique features of these cell surface receptors and how they interact. These interactions are specific, but usually relatively weak, with more hydrophilic forces involved in binding. The receptors appear to have specialized ways to present their key interacting elements for ligand-binding from the cell surface. Cell-cell contacts are multivalent. A large group of cell surface molecules are engaged in interactions. Characteristic weak interactions make possible for each individual molecule pair within the group to constantly associate-dissociate-reassociate, such that the cell-cell recognition becomes a dynamic process. The immunological synapse is a good example for immune receptors to be orchestrated in performing immunological function in a collective fashion.展开更多
Thermoresponsive biotinylated dendronized copolymers carrying dendritic oligoethylene glycol(OEG)pendants were prepared via free radical polymerization,and their protein recognitions based on biotin-avidin interacti...Thermoresponsive biotinylated dendronized copolymers carrying dendritic oligoethylene glycol(OEG)pendants were prepared via free radical polymerization,and their protein recognitions based on biotin-avidin interaction investigated.Both first(PG1) and second generation(PG2) dendronized copolymers were designed to examine possible thickness effects on the interaction between biotin and avidin.Inherited from the outstanding thermoresponsive properties from OEG dendrons,these biotinylated cylindrical copolymers show characteristic thermoresponsive behavior which provides an envelope to capture avidin through switching temperatures above or below their phase transition temperatures(T_(cp)s).Thus,the recognition of polymer-supported biotin with avidin was investigated with UV/vis spectroscopy and dynamic laser light scattering.In contrast to the case for PG1,the increased thickness for copolymer PG2 hinders partially and inhibits the recognition of biotin moieties with avidin either below or above its T_(cp).This demonstrates the significant architecture effects from dendronized polymers on the biotin moieties to shift onto periphery of the collapsed aggregates,which should be a prerequisite for protein recognition.These kinds of novel thermoresponsive copolymers may pave a way for the interesting biological applications in areas such as reversible activity control of enzyme or proteins,and for controlled delivery of drugs or genes.展开更多
In this paper,a novel method to automatically detect protein spots on a two-dimensional (2-D) electrophoresis gel image is proposed to implement proteomics analysis of complex analyte.On the basis of the identifying s...In this paper,a novel method to automatically detect protein spots on a two-dimensional (2-D) electrophoresis gel image is proposed to implement proteomics analysis of complex analyte.On the basis of the identifying spots results based on color variation and spot size features,morphological feature is introduced as a new criterion to distinguish protein spots from non-protein spots.Image-sharpening,edge-detecting and morphological feature extraction methods were consequently combined to detect protein spots on a 2-D electrophoresis gel image subject to strong disturbance.The proposed method was applied to detect the protein spots of proteomic gel images from E.coli cell,human kidney tissue and human serum.The results demonstrated that this method is more accurate and reliable than previous methods such as PDQuest 7.2 and ImageMaster 5.0 software for detecting protein spots on gel images with strong interferences.展开更多
The interaction of the novel tetra-carboxylphenyl calix[4]arene (TCPC) with the bovine heart cytochrome c (Cc) was first investigated by fluorescence spectroscopy and molecular modeling methods. The formation of a...The interaction of the novel tetra-carboxylphenyl calix[4]arene (TCPC) with the bovine heart cytochrome c (Cc) was first investigated by fluorescence spectroscopy and molecular modeling methods. The formation of a stable 1:1 complex was monitored by fluorescence titration, and its binding constant is 1.916 ×10^7 L mol^-1. Molecular modeling reveals the recognition mechanism of TCPC to the Cc surface, that is, the electrostatic interaction drives TCPC to the Cc surface, and the van der Waals interaction orientates TCPC parallel to the cleft of Cc.展开更多
基金Supported by the National Natural Science Foundation (No.39970 15 5 ) the High- Technology Developm entProgram of China (No.2 0 0 1AA 2 330 11) +1 种基金and theNational Frontier Research Program (No.G19990 75 6 0 2 G19990 1190 2 and19980 5 110 5 )
文摘Protein protein recognition is an important step in biological processes, which still largely remains elusive. The inter residue contact potential, CP ij , describes the propensity of contact between two types of residue. In this study, several different CP ij variants were examined with the objective of discriminating the binding potential of surface pairs. Using solvent mediated inter molecule contact potential (SM IMCP ij ), an evaluation model was deduced and tested. Using the evaluation model it was found that the SM IMCP ij gives a better performance than either residue mediated IMCP ij (RM IMCP ij ) or folding residue contact potential (FCP ij ). The results suggest that the evaluation model provides a fast, effective, and discriminative method for the evaluation of proposed binding interfaces.
基金the National Natural Science Foundation of China for Distinguished Young Scholars (Grant No. 50625309)
文摘Surface glycosylation of polymeric membranes has been inspired by the structure of natural biomem-branes. It refers to that glycosyl groups are introduced onto the membrane surface by various strate-gies, which combine the separation function of the membrane with the biological function of the sac-charides in one system. In this review, progress in the surface glycosylation of polymeric membranes is highlighted in two aspects, i.e. the glycosylation methods and the potential applications of the sur-face-glycosylated membranes.
文摘Cell-cell recognition is the key for multicellular organisms to survive. This recognition critically depends on protein-protein interactions from opposing cell surfaces. Recent structural investigations reveal unique features of these cell surface receptors and how they interact. These interactions are specific, but usually relatively weak, with more hydrophilic forces involved in binding. The receptors appear to have specialized ways to present their key interacting elements for ligand-binding from the cell surface. Cell-cell contacts are multivalent. A large group of cell surface molecules are engaged in interactions. Characteristic weak interactions make possible for each individual molecule pair within the group to constantly associate-dissociate-reassociate, such that the cell-cell recognition becomes a dynamic process. The immunological synapse is a good example for immune receptors to be orchestrated in performing immunological function in a collective fashion.
基金the National Natural Science Foundation of China(Nos.21374058,21474060 and 21574078)the Ph.D. Programs Foundation of Ministry of Education of China(No 201331081100166)the Shanghai Rising-Star Program(No.16QA1401800)
文摘Thermoresponsive biotinylated dendronized copolymers carrying dendritic oligoethylene glycol(OEG)pendants were prepared via free radical polymerization,and their protein recognitions based on biotin-avidin interaction investigated.Both first(PG1) and second generation(PG2) dendronized copolymers were designed to examine possible thickness effects on the interaction between biotin and avidin.Inherited from the outstanding thermoresponsive properties from OEG dendrons,these biotinylated cylindrical copolymers show characteristic thermoresponsive behavior which provides an envelope to capture avidin through switching temperatures above or below their phase transition temperatures(T_(cp)s).Thus,the recognition of polymer-supported biotin with avidin was investigated with UV/vis spectroscopy and dynamic laser light scattering.In contrast to the case for PG1,the increased thickness for copolymer PG2 hinders partially and inhibits the recognition of biotin moieties with avidin either below or above its T_(cp).This demonstrates the significant architecture effects from dendronized polymers on the biotin moieties to shift onto periphery of the collapsed aggregates,which should be a prerequisite for protein recognition.These kinds of novel thermoresponsive copolymers may pave a way for the interesting biological applications in areas such as reversible activity control of enzyme or proteins,and for controlled delivery of drugs or genes.
基金the National Natural Science Foundat ion of China(Grant No.90209005) Science and Technology Project of Zhejiang Province(Grant No.2004C33026).
文摘In this paper,a novel method to automatically detect protein spots on a two-dimensional (2-D) electrophoresis gel image is proposed to implement proteomics analysis of complex analyte.On the basis of the identifying spots results based on color variation and spot size features,morphological feature is introduced as a new criterion to distinguish protein spots from non-protein spots.Image-sharpening,edge-detecting and morphological feature extraction methods were consequently combined to detect protein spots on a 2-D electrophoresis gel image subject to strong disturbance.The proposed method was applied to detect the protein spots of proteomic gel images from E.coli cell,human kidney tissue and human serum.The results demonstrated that this method is more accurate and reliable than previous methods such as PDQuest 7.2 and ImageMaster 5.0 software for detecting protein spots on gel images with strong interferences.
基金supported by the National Natural Science Foundation of China (No.90813018)the Youth Foundation of Shanxi Province (No.2006021009)as well as the Youth Scientific and Technical Foundation of Shanxi University (Nos.2006007 and 2007112).
文摘The interaction of the novel tetra-carboxylphenyl calix[4]arene (TCPC) with the bovine heart cytochrome c (Cc) was first investigated by fluorescence spectroscopy and molecular modeling methods. The formation of a stable 1:1 complex was monitored by fluorescence titration, and its binding constant is 1.916 ×10^7 L mol^-1. Molecular modeling reveals the recognition mechanism of TCPC to the Cc surface, that is, the electrostatic interaction drives TCPC to the Cc surface, and the van der Waals interaction orientates TCPC parallel to the cleft of Cc.