Interaction of D-phenylalanine with Co(II)-substituted rabbit muscle pyruvate kinase: kinetic and optical properties

1982 ◽  
Vol 60 (9) ◽  
pp. 861-866
Author(s):  
Chiu-Yin Kwan ◽  
Robert C. Davis
Keyword(s):  
Amino Acids ◽  
Optical Properties ◽  
Pyruvate Kinase ◽  
Conformational Changes ◽  
Metal Ion ◽  
Inhibitory Effect ◽  
Rabbit Muscle ◽  
Divalent Metal Ion ◽  
Muscle Pyruvate Kinase ◽  
Difference Absorption

The kinetic and optical properties of Co(II)-substituted pyruvate kinase in the presence of D-phenylalanine (D-Phe) were investigated. The results are discussed in comparison with the effects of its optical isomer L-phenylalanine (L-Phe) on the same enzyme. The catalytic effect of D-Phe on rabbit muscle pyruvate kinase depended upon the nature of the activating divalent metal ion used. It has stimulatory effect on Mg(II)-activated enzyme, but inhibitory effect on Co(II)-activated enzyme. Unlike the inhibitory effect of L-Phe, the inhibition of Co(II)–enzyme by D-Phe was not sensitive to the changes of pH and temperature, could not be reversed by L-alanine (L-Ala), displayed hyperbolic kinetics, and was noncompetitive with respect to phosphoenolpyruvate saturation. D-Phe induced substantial visible circular dichroism (CD) spectral changes of Co(II)–enzyme similar to those induced by L-Phe. Although ultraviolet CD spectrum was not affected, D-Phe induced an ultraviolet difference absorption spectral change very similar to, but much smaller than, that induced by L-Phe. Our results support that D-Phe and other amino acids interact with the enzyme at two different sites: a common site, causing similar conformational changes which bear little direct kinetic relevance, and a kinetically relevant site, which is sterically dependent upon the side chain of the amino acids.

pH-Dependent amino acid induced conformational changes of rabbit muscle pyruvate kinase

1980 ◽  
Vol 58 (3) ◽  
pp. 188-193 ◽  
Author(s):  
Chiu-Yin Kwan ◽  
Robert C. Davis
Keyword(s):  
Metal Ions ◽  
Pyruvate Kinase ◽  
Conformational Changes ◽  
Divalent Metal ◽  
Rabbit Muscle ◽  
Divalent Metal Ions ◽  
Spectral Changes ◽  
Metal Derivatives ◽  
Muscle Pyruvate Kinase ◽  
Difference Absorption

The interactions of L-Phe and L-Ala with rabbit muscle pyruvate kinase depended upon the nature of divalent metal ions studied: Mg(II), Co(II), Mn(II), and Ni(II). L-Phe inhibited all metal derivatives of the enzyme except Mn(II)–enzyme. L-Ala inhibited only Ni(II)–enzyme and had no effect on other metal derivatives. The inhibition by L-Phe could be partially or completely reversed by L-Ala for all metal derivatives. The mode of inhibition of pyruvate kinase by L-Phe depended upon pH as well as the nature of activating divalent metal ions. The sigmoidal response increased with increasing pH for all metal derivatives inhibited by L-Phe. L-Phe and L-Ala strongly perturbed the coordination sphere of enzyme bound Co(II), but not Ni(II). There were poor correlations between visible circular dichroic (cd) spectral changes and the corresponding kinetic changes. However, L-Phe and (or) L-Ala induced ultraviolet cd and difference absorption spectral changes, on the other hand, corresponded remarkably well with the kinetic observations.

scholarly journals Inhibitory effect of Zn2+ on rabbit muscle pyruvate kinase and reactivation by histidine.

1981 ◽  
Vol 27 (2) ◽  
pp. 107-116 ◽  
Author(s):  
Nanaya TAMAKI ◽  
Tatsuhiko IKEDA ◽  
Keiko KIMURA ◽  
Sachiko MORIOKA
Keyword(s):  
Pyruvate Kinase ◽  
Inhibitory Effect ◽  
Rabbit Muscle ◽  
Muscle Pyruvate Kinase

Comparative studies of kinetic and optical properties of rabbit muscle, sturgeon muscle, and yeast pyruvate kinase

1980 ◽  
Vol 58 (3) ◽  
pp. 194-200 ◽  
Author(s):  
Chiu-Yin Kwan ◽  
Jerome L. Gabriel ◽  
Robert C. Davis
Keyword(s):  
Optical Properties ◽  
Metal Ions ◽  
Pyruvate Kinase ◽  
Conformational Changes ◽  
Rabbit Muscle ◽  
Divalent Metal Ions ◽  
Muscle Enzymes ◽  
Muscle Enzyme ◽  
Allosteric Effectors ◽  
Functional Features

The kinetic and optical properties of pyruvate kinase isolated from rabbit muscle, sturgeon muscle, and yeast were compared using various activating divalent metal ions as probes for functional features and using ultraviolet circular dichroism (cd) measurements for conformational features, respectively. All three preparations of pyruvate kinase were similar in many aspects, such as activating efficiencies of the four activating metal ions, Mg(II), Co(II), Mn(II), and Ni(II) and pH-rate profiles, suggesting the presence of a similar metal binding locus of these enzymes as well as a common underlying mechanism of action. L-Phe inhibited the rabbit muscle enzyme and turned the hyperbolic kinetics into a sigmoidal kinetic with respect to phosphoenolpyruvate at alkaline pH, while fructose-1,6-biphosphate activated the sturgeon muscle and yeast enzymes and turned the sigmoidal kinetics into hyperbolic kinetics with respect to phosphoenolpyruvate. The ultraviolet cd spectral changes qualitatively correlated well with kinetic observations of all three native enzymes in the presence and absence of allosteric effectors. Our results suggested that there are at least two conformational states of pyruvate kinase which are inducible by the binding of substrate and (or) allosteric effectors. The conformational changes from one form to another in these enzymes are very similar, especially between the rabbit and sturgeon muscle enzymes.

scholarly journals A kinetic study of rabbit muscle pyruvate kinase

1973 ◽  
Vol 131 (2) ◽  
pp. 223-236 ◽  
Author(s):  
S. Ainsworth ◽  
N. Macfarlane
Keyword(s):  
Reaction Mechanism ◽  
Kinetic Study ◽  
Pyruvate Kinase ◽  
Random Order ◽  
Experimental Results ◽  
Rabbit Muscle ◽  
Dead End ◽  
Inhibition Constants ◽  
Muscle Pyruvate Kinase ◽  
Kinetics Of

The paper reports a study of the kinetics of the reaction between phosphoenolpyruvate, ADP and Mg2+ catalysed by rabbit muscle pyruvate kinase. The experimental results indicate that the reaction mechanism is equilibrium random-order in type, that the substrates and products are phosphoenolpyruvate, ADP, Mg2+, pyruvate and MgATP, and that dead-end complexes, between pyruvate, ADP and Mg2+, form randomly and exist in equilibrium with themselves and other substrate complexes. Values were determined for the Michaelis, dissociation and inhibition constants of the reaction and are compared with values ascertained by previous workers.

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