Solute transport on the sub 100 ms scale across the lipid bilayer membrane of individual proteoliposomes.

Screening assays designed to probe ligand and drug-candidate regulation of membrane proteins responsible for ion-translocation across the cell membrane are wide spread, while efficient means to screen membrane-protein facilitated transport of uncharged solutes are sparse. We report on a microfluidic-based system to monitor transport of uncharged solutes across the membrane of multiple (>100) individually resolved surface-immobilized liposomes. This was accomplished by rapidly switching (<10 ms) the solution above dye-containing liposomes immobilized on the floor of a microfluidic channel.

Differential inhibition of homotrimeric dUTPases by the 3'-azido derivative of dideoxy-UTP.

The inhibitory effects of 3'-azido-2',3'-dideoxyuridine-5'-triphosphate in complex with the Mg2+ ion (azido-ddUTP.Mg) on the dUTPases of the human, E. coli, and equine infectious anemia virus have been compared.

High-resolution x-ray structure of human aquaporin 5.

Human aquaporin 5 (HsAQP5) facilitates the transport of water across plasma membranes and has been identified within cells of the stomach, duodenum, pancreas, airways, lungs, salivary glands, sweat glands, eyes, lacrimal glands, and the inner ear. AQP5, like AQP2, is subject to posttranslational regulation by phosphorylation, at which point it is trafficked between intracellular storage compartments and the plasma membrane. Details concerning the molecular mechanism of membrane trafficking are unknown.

A double role for a strictly conserved serine: further insights into the dUTPase catalytic mechanism.

Ser72 at the active site of the Escherichia coli dUTPase has been mutated to an alanine, and the properties of the mutant have been investigated. The serine is absolutely conserved among the monomeric and trimeric dUTPases (including the bifunctional dCTP deaminase:dUTPases), and it has been proposed to promote catalysis by balancing negative charge at the oxygen that bridges the alpha- and beta-phosphorus of the substrate. In all reported complexes of dUTPases with the substrate analogue alpha,beta-imido-dUTP.

Effects of surface adsorption on catalytic activity of heavy meromyosin studied using a fluorescent ATP analogue.

Biochemical studies in solution and with myosin motor fragments adsorbed to surfaces (in vitro motility assays) are invaluable for elucidation of actomyosin function. However, there is limited understanding of how surface adsorption affects motor properties, e.g.