N. L. Zakharchenko

Chaperone-like activity of β-casein and thermal stability of alcohol dehydrogenase

Correlation between structural peculiarities of beta-casein and its chaperon-like activity was investigated using the recombinant forms of the protein containing the cysteine residues in the polypeptide chain. Aggregation of native and modified forms of β-casein was studied, as well as their chaperon-like activity towards alcohol dehydrogenase thermal aggregation. It has been shown that dimeric and oligomeric forms of β-casein, which are formed due to intermolecular disulfide bonds, significantly differ in their physicochemical and chaperon-like properties from monomeric forms. The thermal stability of alcohol dehydrogenase has been found to depend on the β-casein concentration.

Effect of Electrolytes on the Catalytic Properties and Sructural Characteristics of Dodecylpyridinium Bromide Micelles

Electrolyte-induced structural rearrangements of dodecylpyridinium bromide micelles affect their catalytic properties in alkaline hydrolysis of phosphonic esters.

Effect of trypsin microenvironment on the rate constants of elementary stages of the hydrolysis reaction of Nα-Benzoyl-L-arginine ethyl ester

The hydrolysis reaction of Nα-benzoyl-L-arginine ethyl ester catalyzed by trypsin from pig pancreas was comparatively studied in an aqueous buffer solution and in the system of reversed micelles of Aerosol OT in octane (pH 8.5) to determine the mechanisms of influence of the enzyme microenvironment on the rate constants of the elementary stages of the enzymatic reaction. The temperature dependences of the catalytic constant kcat and the rate constant of the second order kcat/Km (s, catalysis efficiency) allowed the determination of the rate constants and the activation energy of elementary stages of the enzymatic reaction. It was revealed that a decrease in the efficiency of catalytic action of trypsin in reverse micelles in comparison with an aqueous solution is first of all determined by a decrease in the rate constant of formation of the enzyme-substrate complex k1. Possible mechanisms of the effect of the microenvironment on the elementary stages of catalytic action of the enzyme are discussed.

Reactivity of Amphiphilic Calix[4]resorcinolarenes and Phenols in the Reverse Micellar System Sodium Bis(2-ethylhexyl) Sulfosuccinate-Decane-Water

The mechanism of reaction of calix[4]resorcinolarene, aminomethylated calix[4]resorcinolarene, and 2-(dimethylaminomethyl)-4-isononylphenol with ethyl 4-nitrophenyl (chloromethyl)phosphonate in the reverse micellar system anionic surfactant-sodium bis(2-ethylhexyl) sulfosuccinate-decane-water changes compared with direct micellar systems and aqueous-organic solutions. It was shown that the calix[4]resorcinolarenes and phenol studied increase the percolation threshold of the system.

Alkaline hydrolysis of ethylp-nitrophenyl chloromethylphosphonate in the reverse micellar AOT—decane—water system

The influence of cluster formation of micelles on the rate of alkaline hydrolysis of ethylp-nitrophenyl chloromethylphosphonate in the reverse micellar sodium bis(2-ethylhexyl) sulfosuccinate (AOT)—decane—water system was found. The applicability of the pseudo-phase model of micellar catalysis below and above the percolation threshold was shown.

Kinetics of alkaline hydrolysis of ethylp-nitrophenyl ethylphosphonate in the reverse micellar system: sodium dodecyl sulfate-hexanol-water

The kinetics of alkaline hydrolysis of ethylp-nitrophenyl ethylphosphonate in the reverse micellar system sodium dodecyl sulfate—hexanol—water was studied. At high pH and low water content, the process occurs at the surface layer and can satisfactorily be described by the pseudo-phase model equation.