Understanding of cellular processes and underlying molecular events requires knowledge about different aspects of molecular interactions, networks of molecules and pathways in addition to the sequence, structure and function of individual molecules involved. Databases of interacting molecules, pathways and related chemical reaction equations have been developed. The kinetic data for these inter...

in this research complexation of dioxovanadium(v) with nitrilotriacetic acid (nta) at differentionic strengths (0.1 to 1.0 mol dm-3) of sodium perchlorate as supporting electrolyte and ph rangeof 1.00-2.50 at 25 °c has been investigated by a combination of potentiometric and uvspectrophotometric measurements. stability constants of two species, v0211l- and vo2h2l havebeen calculated. ionic stre...

Seven proteins have been isolated from sarcoplasmic reticulum. These proteins have been identified as an ATPase, a series of water soluble, acidic proteins of molecular weights 55,000, 46,500, 38,000, 33,000, and 20,000, and a proteolipid. The interactions of the acidic proteins with Ca2+ have been measured at pH 7.5 in the presence and absence of 0.1 M KCl. The protein of molecular weight 55,0...

The Whitten-Rabinovitch (WR) approximation used in the semi-classical calculation of the Rice-Ramsperger-Kassel-Marcus (RRKM) unimolecular reaction rate constant was improved for reliable application to protein reactions. The state sum data for the 10-mer of each amino acid calculated by the accurate Beyer-Swinehart (BS) algorithm were used to obtain the residue-specific correction functions (w...

A filter binding assay was developed that allows measurement of specific binding of trp repressor to operator DNA. The most important feature of this procedure is the concentration and type of salt present in the binding buffer. Using this assay the dissociation constant of the repressor-operator complex was determined to be 2.6 X 10(-9) M, and 1.34 repressor dimers were found to be bound to ea...

Fuel cells used for transport applications hold polymer membranes as a key element. Their efficiency can be significantly increased if structured ion channels are implemented at the molecular level into proton-conducting membrane. New functional molecules with selective affinity ionomers needed to obtain such membrane design. This study presents method screen peptide binders perfluorinated sulf...

Di-isopropylfluorophosphatase (DFPase) is shown to contain two high-affinity Ca(2+)-binding sites, which are required for catalytic activity and stability. Incubation with chelating agents results in the irreversible inactivation of DFPase. From titrations with Quin 2 [2-([2-[bis(carboxymethyl)amino]-5-methylphenoxy]-methyl)-6-methoxy-8-[bis(carboxymethyl)-amino]quinoline], a lower-affinity sit...

The effect of extracellular and intracellular Na(+) on the single-channel kinetics of Mg(2+) block was studied in recombinant NR1-NR2B NMDA receptor channels. Na(+) prevents Mg(2+) access to its blocking site by occupying two sites in the external portion of the permeation pathway. The occupancy of these sites by intracellular, but not extracellular, Na(+) is voltage-dependent. In the absence o...

Scanning tunneling microscopy study of O2 dissociation on Rh~110! at 170 K shows a low-energy dissociation coordinate for a precursor with the O-O axis aligned in the @001# azimuth, indicating a strong influence of the surface anisotropy on the potential-energy surface. This results in pairs of oxygen atoms oriented along @001#, which aggregate in chains along @11̄0# . The atomic distance in the...

The effect of the large impact parameter near-elastic peak of collisional energy transfer for unimolecular dissociation/bimolecular recombination reactions is studied. To this end, the conventional single exponential model, a biexponential model that fits the literature classical trajectory data better, a model with a singularity at zero energy transfer, and the most realistic model, a model wi...