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V F Makeeva

Publications and source records attributed to V F Makeeva.

At least 19 recordsLinked to original sources
PubMed2001

Studies on interaction of phosphorylase kinase from rabbit skeletal muscle with glycogen in the presence of ATP and ADP.

The influence of ATP on complex formation of phosphorylase kinase (PhK) with glycogen in the presence of Ca(2+) and Mg(2+) has been studied. The initial rate of complex formation decreases with increasing ATP concentration, the dependence of the initial rate on the concentration of ATP having a cooperative character. Formation of the complex of PhK with glycogen in the presence of ATP occurs after a lag period, which increases with increasing ATP concentration. The dependence of the initial rate of complex formation (v) on the concentration of non-hydrolyzed ATP analogue, beta,gamma-methylene-ATP, follows the hyperbolic law. A correlation between PhK-glycogen complex formation and (32)P incorporation catalyzed by PhK itself and by the catalytic subunit of cAMP-dependent protein kinase has been shown. For ADP (the product and allosteric effector of the PhK reaction) the dependence of v on ADP concentration has a complicated form, probably due to the sequential binding of ADP at two allosteric sites on the beta subunit and the active site on the gamma subunit.

Adenosine Diphosphate↗
PubMed1999

A tentative mechanism of the ternary complex formation between phosphorylase kinase, glycogen phosphorylase b and glycogen.

The kinetics of rabbit skeletal muscle phosphorylase kinase interaction with glycogen has been studied. At pH 6.8 the binding of phosphorylase kinase to glycogen proceeds only in the presence of Mg2+, whereas at pH 8.2 formation of the complex occurs even in the absence of Mg2+. On the other hand, the interaction of phosphorylase kinase with glycogen requires Ca2+ at both pH values. The initial rate of the complex formation is proportional to the enzyme and glycogen concentrations, suggesting the formation of the complex with stoichiometry 1:1 at the initial step of phosphorylase kinase binding by glycogen. According to the kinetic and sedimentation data, the substrate of the phosphorylase kinase reaction, glycogen phosphorylase b, favors the binding of phosphorylase kinase with glycogen. We suggest a model for the ordered binding of phosphorylase b and phosphorylase kinase to the glycogen particle that explains the increase in the tightness of phosphorylase kinase binding with glycogen in the presence of phosphorylase b.

Animals↗
PubMed1999

Kinetics of the interaction of rabbit skeletal muscle phosphorylase kinase with glycogen.

The kinetics of the interaction of rabbit skeletal muscle phosphorylase kinase with glycogen was studied by the turbidimetric method at pH 6.8 and 8.2. Binding of phosphorylase kinase by glycogen occurs only in the presence of Ca2+ and Mg2+. The initial rate of complex formation is proportional to the enzyme and polysaccharide concentration; this suggests the formation of a complex with 1:1 stoichiometry in the initial step of phosphorylase kinase binding by glycogen. The kinetic data suggest that phosphorylase kinase substrate--glycogen phosphorylase b--favors the binding of phosphorylase kinase with glycogen. This conclusion is supported by direct experiments on the influence of phosphorylase b on the interaction of phosphorylase kinase with glycogen using analytical sedimentation analysis. The kinetic curves of the formation of the complex of phosphorylase kinase with glycogen obtained in the presence of ATP are characterized by a lag period. Preincubation of phosphorylase kinase with ATP in the presence of Ca2+ and Mg2+ causes the complete disappearance of the lag period. On changing the pH from 6.8 to 8.2, the rate of phosphorylase kinase binding by glycogen is appreciably increased, and complex formation becomes possible even in the absence of Mg2+. A model of phosphorylase kinase and phosphorylase b adsorption on the surface of the glycogen particle explaining the increase in the strength of phosphorylase kinase binding with glycogen in the presence of phosphorylase b is proposed.

Adenosine Triphosphate↗
PubMed1997

Continuous enzymatic assay for phosphorylase kinase in a monocascade enzyme system.

A turbidimetric method for continuous monitoring of the enzymatic reaction catalyzed by rabbit skeletal muscle phosphorylase kinase has been developed. The reaction mixture contained the substrates of glycogen phosphorylase a, i.e., glycogen and glucose 1-phosphate (or P(i)), in addition to the usual components of the kinase reaction. The kinetics of the cascade enzyme system were followed by the change in glycogen concentration over time, as measured by the absorbance of the reaction medium at 360 nm. The reliability of this turbidimetric method for measuring phosphorylase kinase activity was proven by comparison with a commonly used radiochemical assay. We present here a newly developed method for calculating the initial rate of phosphorylase kinase reaction in our conjugated system. We demonstrate that our procedure is applicable for investigating the hysteretic properties of phosphorylase kinase.

Animals↗
PubMed1996

Hysteretic properties of rabbit skeletal muscle phosphorylase kinase: synergistic activation by phosphorylase b, Ca2+, and Mg2+.

To study the hysteretic properties of rabbit skeletal muscle phosphorylase kinase the method of continuous registration of the kinetics of the kinase reaction developed by us earlier has been used. It was shown that duration of the lag period on the kinetic curves is independent of the phosphorylase kinase concentration and the simultaneous presence of phosphorylase b, Ca2+, and Mg2+ is required for the complete transition of the enzyme into the activated state.

Adenosine Triphosphate↗
PubMed1995

[Kinetics of action of phosphorylase kinase in a cascade enzymatic system. III. Hysteretic properties of phosphorylase kinase from skeletal muscles].

The kinetic behaviour of rabbit skeletal muscle phosphorylase kinase at variable concentrations of the enzyme and the substrate (glycogen phosphorylase b) has been studied. The kinetic curves reveal a lag period whose duration decreases with a rise in the phosphorylase kinase concentration (when the reaction is initiated by an addition of the ATP + MgCl2 mixture to the enzyme preincubated with phosphorylase b, CaCl2, glycogen and glucose-1-phosphate or inorganic phosphate). A decrease of the phosphorylase b concentration eliminates the lag period. Under these conditions the specific activity of phosphorylase kinase decreases with a rise in the enzyme concentration. The kinetic behaviour of phosphorylase kinase is interpreted in terms of a model of a linearly associating system, such as M reversible M2 reversible M3 reversible ...Mi, where M is the dexadecameric molecule of phosphorylase kinase. Acceleration of the phosphorylase kinase-catalyzed reaction in the course of the enzymatic process seems to be due to the breakdown of inactive enzyme associates (Mi) caused by phosphorylase b. The short gamma-subunit of phosphorylase kinase devoid of the calmodulin-binding domain does not display any hysteretic properties.

Animals↗
PubMed1995

[Kinetics of action of phosphorylase kinase in an enzymatic cascade system. II. Assessment of the initial rate of the enzymatic reaction catalyzed by phosphorylase kinase].

The turbidimetric method for determining the phosphorylase kinase activity has been developed. The reaction mixture contained, alongside with other components of the kinase reaction, also the substrates of glycogen phosphorylase a, the final product of the kinase reaction-glycogen and glucose 1-phosphate (or inorganic phosphate). The kinetics of the cascade enzymatic system were followed by the increment (decrement) of absorbance of the glycogen solution at 360 nm (delta A). The initial rate of the phosphorylase kinase-catalyzed enzymatic reaction, nu 0, can be calculated according to the formula: nu 0 = 2tg alpha/a2, where tg alpha is the initial slope of the kinetic curve in the coordinates: delta A-(time)2 and a2 is the specific enzymatic activity of phosphorylase a. The latter was estimated from the initial rates of the phosphorylase reaction measured by the addition of glycogen to the reaction mixture after the completion of the kinase reaction. The reliability of the turbidimetric method for determining the phosphorylase kinase activity was proved by comparison with a direct method based on the measurement of the amount of incorporated 32P.

Animals↗
PubMed1989

[Phosphorylation of isolated components of the troponin complex of skeletal and cardiac muscle phosphorylase kinase from bird skeletal muscles].

Pigeon and chicken skeletal muscle phosphorylase kinase purified to a nearly homogeneous state is able to phosphorylate both cardiac and skeletal troponin I and T. After 1-hr incubation, the enzyme transfers up to 0.35 mole of phosphorus per mole of skeletal troponin I, up to 0.5 mole of cardiac troponin I and up to 0.1 mole of cardiac and skeletal troponin T. Avian muscle phosphorylase kinase does not phosphorylate the first serine residue of cardiac and skeletal troponin T, but catalyzes the phosphate incorporation into the site(s) of troponin T located in the central or C-terminal parts of the protein molecule. The rate of troponin phosphorylation by pigeon muscle phosphorylase kinase is pH-dependent: the 6.8/8.2 ratio for troponin I is close to 0,2, whereas that with troponin T varies in the range of 0.5-0.7. Troponin phosphorylation by avian phosphorylase kinase depends on the presence of Ca2+ in the incubation mixture. In the presence of 3 mM EGTA troponin I phosphorylation is inhibited by 70-90%, whereas that of troponin T--by 50%. The experimental results indicate that the phosphorylation of troponin I and T is catalyzed either by two different active centers or by different conformations of the single center of avian phosphorylase kinase.

Animals↗
PubMed1989

[Molecular mechanisms of the regulation of phosphorylase kinase from skeletal muscles of mammals and birds].

Red and white avian skeletal muscles (chicken and pigeon) contain the same alpha'-isoenzyme of phosphorylase kinase. According to data from gradient polyacrylamide slab electrophoresis in the presence of SDS, the molecular masses of beta- and gamma-subunits of phosphorylase kinase from rabbit, chicken and pigeon muscles are not identical. Electron microscopy data suggest that the quaternary structure of chicken and pigeon phosphorylase kinase is of the same type. The alpha'-isozyme of chicken and pigeon phosphorylase kinase is strongly activated by calmodulin and troponin C. Avian phosphorylase kinase is activated 2--3-fold by phosphorylation with cAMP-dependent protein kinase and by autophosphorylation. This activation is associated with the phosphorylation of both alpha'- and beta-subunits. The affinity of pigeon phosphorylase kinase a for Ca2+ is 20 times as high as that of phosphorylase kinase b.

Animals↗
PubMedDate not supplied

[Decrease in the radiation effect in the lymphoid organs of animals adapting to altitude].

Adaptation to altitude hypoxia exerts a positive effect on the cell density of lymph organs of gamma-irradiated animals. It also reduces radiation degradation of DNA, its availability to DNase in the nuclear chromatin and disorders in the activity of DNA polymerases. The role of inhibition of radiation-induced degradation of chromatin DNA in the protective effect of altitude adaptation on the cell density of lymph organs is discussed.

Adaptation, Physiological↗
PubMedDate not supplied

[Nucleic acids of the lymphoid cells of the pregnant rat subjected to space flight and its progeny].

The space flight effect on the synthesis of nucleic acids in spleen lymphocytes in pregnant rats and their offspring was investigated. In addition to the inhibition of the DNA replicative function previously detected in males, activation of RNA synthesis was seen in the pregnant females. Such changes did not develop in the synchronous mockup controls. The 30-day and 100-day old pups of the rats flown in space during the last third of their pregnancy showed no changes in the DNA replicative function. The 100-day old animals displayed only a slight, when compared to the vivarium controls, decline of RNA synthesis which was produced by concomitant factors rather than by microgravity per se. It is supposed that microgravity-induced activation of RNA synthesis in spleen lymphocytes of pregnant rats is associated with the involvement of these cells in adaptive trophic processes that are to maintain plastic homeostasis of the fetus in an unusual environment.

Animals↗