Crystallization and preliminary analysis of enzyme-substrate complexes of pyruvate kinase from rabbit muscle

1991 ◽  
Vol 11 (2) ◽  
pp. 153-157 ◽  
Author(s):  
Karen Schmidt-Bäse ◽  
Jenny L. Buchbinder ◽  
George H. Reed ◽  
Ivan Rayment
Keyword(s):  
Pyruvate Kinase ◽  
Preliminary Analysis ◽  
Rabbit Muscle ◽  
Enzyme Substrate

scholarly journals Phosphocreatine does not inhibit rabbit muscle phosphofructokinase or pyruvate kinase.

1979 ◽  
Vol 254 (22) ◽  
pp. 11357-11359
Author(s):  
C.D. Fitch ◽  
R. Chevli ◽  
M. Jellinek
Keyword(s):  
Pyruvate Kinase ◽  
Rabbit Muscle

scholarly journals Fructose 1,6-bisphosphate aldolase from rabbit muscle. The isomerization of the enzyme-dihydroxyacetone phosphate complex

1977 ◽  
Vol 167 (2) ◽  
pp. 361-366 ◽  
Author(s):  
E Grazi ◽  
M Blanzieri
Keyword(s):  
Competitive Inhibitor ◽  
Dihydroxyacetone Phosphate ◽  
Rabbit Muscle ◽  
Keto Form ◽  
First Order ◽  
Phosphate Complex ◽  
Substrate Complex ◽  
Enzyme Substrate ◽  
Dead End ◽  
Fructose 1,6 Bisphosphate

The formation and dissociation of the aldolase-dihydroxyacetone phosphate complex were studied by following changes in A240 [Topper, Mehler & Bloom (1957), Science 126, 1287-1289]. It was shown that the enzyme-substrate complex (ES) slowly isomerizes according to the following reaction: (formula: see text) the two first-order rate constants for the isomerization step being k+2 = 1.3s-1 and k-2 = 0.7s-1 at 20 degrees C and pH 7.5. The dissociation of the ES complex was provoked by the addition of the competitive inhibitor hexitol 1,6-bisphosphate. At 20 degrees C and pH 7.5, k+1 was 4.7 X 10(6)M-1-S-1 and k-1 was 30s-1. Both the ES and the ES* complexes react rapidly with 1.7 mM-glyceraldehyde 3-phosphate, the reaction being practically complete in 40 ms. This shows that the ES* complex is not a dead-end complex. Evidence was also provided that aldolase binds and utilizes only the keto form of dihydroxyacetone phosphate.

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.

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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