[Modeling of the activity kinetics of oligomer enzymes using phosphofructokinase as an example. III. A polyligand model].

A general statistical-thermodynamical theory of the oligomeric enzymes was applied for description of the complex regulatory properties of human erythrocyte phosphofructokinase (PFC, EC 2.7.1.

[Simulation of the kinetics of oligomeric enzymes as illustrated by phosphofructokinase. I. General analysis of experimental data and the choice of an adequate model].

On the example of complex allosteric kinetics of phosphofructokinase from human erythrocytes we analysed the applicability of the Monod-Wyman-Changeux and association--dissociation models to the unified description of the kinetics of the oligomeric enzymes. It was shown that these models were not sufficient to construct an adequate phosphofructokinase model. We propose to use the unidimensional Izing model for this purpose.

[A model of the allosteric behavior of phosphofructokinase from rabbit muscles determined by the action of adenine nucleotides].

A complex of programs in BASIC has been elaborated, the first part of which is intended for the calculation of concentrations of different ionic forms of the metabolites that are engaged in a complex equilibrium system of the metal-ligand mixture-H+ type. The second part of the complex is employed in the simulation of allosteric kinetics on the basis of the Monod-Wyman-Changeux model. The calculation of ratios of different components in the Mg2+-AMP, ADP and ATP system is used for the semi-quantitative description of regulation of rabbit muscle phosphofructokinase by adenyl nucleotides at pH 7.

[Comparative properties of multiple forms of rabbit muscle phosphofructokinase].

Some properties of three interconvertible forms of rabbit muscle phosphofructokinase specifically eluted from DEAE-cellulose with 19 mM citrate in 0.1 M tris-phosphate buffer, pH 8,0 (I), with 0,3 M buffer (II) and 1.5 M NaCl (III) are compared.

[Choice of the association model of rabbit muscle phosphofructokinase using mathematical modeling].

The sedimentation behaviour of the subform of rabbit muscle phosphofructokinase specifically eluted from DEAE cellulose by citrate was studied in different media by velocity experiments. The measured sedimentation coefficients of different components in the system can be classified into 12 groups, which is indicative of a complex multistep association process of the enzyme (with more than 3 oligomers). The concentration dependence of weight average sedimentation coefficient of phosphofructokinase was a studied.