Co-precipitation of enzymes in metal-organic frameworks is a unique enzyme-immobilization strategy but challenged by weak acid-base stability. To overcome this drawback, we discovered that Ca2+ can co-precipitate with carboxylate ligands and under ambient aqueous conditions form [email protected] material composites stable wide range pHs (3.7–9.5). We proved on four varied isoelectric points, m...

Structure-based virtual screens were carried out against beta-secretase (BACE1) to investigate the impact of ligand protonation on screening efficacy. A comparative evaluation of the performance and its dependence on ligand protonation states docking by Surflex, eHiTS, GOLD, and FlexX-Pharm was performed. Virtual screening performed by FlexX-Pharm (EF(1%)=69) and Surflex (EF(1%)=58) provided th...

The binding sites of wild-type avian influenza A H5N1 neuraminidase, as well as those of the Tamiflu (oseltamivir)-resistant H274Y variant, were explored computationally to design inhibitors that target simultaneously several adjacent binding sites of the open conformation of the virus protein. The compounds with the best computed free energies of binding, in agreement by two docking methods, c...

Attachment of a proton sponge to a phosphine ligand renders neutral complexes of the ligand highly amenable to analysis by electrospray ionisation mass spectrometry (ESI-MS). The ligand 1,8-bis(dimethylamino)naphthyldiphenylphosphine (3) is extremely efficient and highly selective in forming exclusively [M + H]+ ions, which may be detected at very low concentration. Ionisation efficiency of 3 i...

A family of genetically-encoded metabolite sensors has been constructed using bacterial periplasmic binding proteins (PBPs) linearly fused to protein fluorophores. The ligand-induced conformational change in a PBP allosterically regulates the relative distance and orientation of a fluorescence resonance energy transfer (FRET)-compatible protein pair. Ligand binding is transduced into a macrosco...

In this report, we systematically studied the effects of different metal ions on the fluorescence of common thiolate ligand capped quantum dots. Generally, heavy metal ions exhibited much more significant fluorescence quenching. Also, the coordination capability and steric hindrance of the ligand jointly affect the quenching efficiency.

Plasmodium falciparum malaria parasites with different capabilities of invading sialic acid-deficient erythrocytes were identified. Thai-2 parasites cultured in Tn erythrocytes invaded neuraminidase-treated and Tn erythrocytes twice as efficiently as Thai-2 parasites cultured in normal erythrocytes and seven to ten times more efficiently than a cloned line of Camp parasites cultured in normal e...

Molecular conjugates, or polyplexes, are promising synthetic vectors for targeted, in vivo gene delivery, if their efficiency can be improved. Gaining mechanistic information on conjugate gene delivery can potentially yield significant improvements in transfer efficiency by revealing barriers to conjugate transfer from the cell surface to the nucleus. We have developed an experimental system th...

Poly(L-lactide) (PLA) microspheres tailored with a tridentate chelating group were radiolabeled with [(99m)Tc(H(2)O)(3)(CO)(3)](+) and optimized for labeling efficiency and stability. Various ligand-polymer blend compositions with commercial PLA (from 2% to 100%) were evaluated. Labeling efficiencies over 95% were achieved in a 5 min reaction using 100% of the ligand-polymer or within 15 min us...

Using H-2Kd-restricted photoprobe-specific cytotoxic T lymphocyte (CTL) clones, which permit assessment of T cell receptor (TCR)-ligand interactions by TCR photoaffinity labeling, we observed that the efficiency of antigen recognition by CTL was critically dependent on the half-life of TCR-ligand complexes. We show here that antigen recognition by CTL is essentially determined by the frequency ...