Pyruvate kinase isozymes

K8. Kanno, H., Fujii, H., Tsujino, G., and Miwa, S., Molecular basis of impaired pyruvate kinase isozyme conversion in erythroid cells A single amino acid substitution near the active site and decreased mRNA content of the R-type PK. Biochem. Biophys. Res. Commun. 192, 46-52... 

Kahn A, Marie J, Boivin P. Pyruvate kinase isozymes in man. II. L type and erythrocyte-type isozymes. Electrofocusing and immunologic studies. Hum Genet 1976 33 35-46. 

Storey, K. B. (1985b). Kinetic and regulatory properties of pyruvate kinase isozymes from flight muscle and fat body of the cockroach, Periplaneta americana. J. Comp. Physiol. 155, 339-345. 

See also Enzymes of Glycolysis, Molecules of Glycolysis, Glycolysis, Pyruvate Kinase Regulation, Pyruvate Kinase Isozymes, Substrate Level Phosphorylation, Phosphoglycerate Kinase, Action of Glucagon... 

Guderley, H. Cardenas, J.M. A study of the catalytic properties of pyruvate kinase isozymes from salmon and an examination of their functional relationships. J. Exp. Zook, 212, 269-277 (1980)... 

Imamura, K. Tanaka, T. Pyruvate kinase isozymes from rat. Methods EnzymoL, 90, 150-165 (1982)... 

Lin, M. Turpin, D.H. Plaxton, W.C. Pyruvate kinase isozymes from the green alga, Selenastrum minutum. I. Purification and physical and immunological characterization. Arch. Biochem. Biophys., 269, 219-227 (1989)... 

Farrar, G. Farrar, W.W. Purification and properties of the pyruvate kinase isozyme Ml from the pig brain. Int. J. Biochem. Cell Biol., 27, 1145-1151 (1995)... 

Table 3.4. Comparison of mammalian and avian pyruvate kinase isozymes ...

Strandholm, J.J., Cardenas, J.M. Dyson, R.D. (1975). Pyruvate kinase isozymes in adult and fetal tissues of chicken. 

Pyruvate kinase (PK) deficiency (MIM 255200) Presumably a variety of mutations in the gene for the R (red cell) isozyme of PK... 

Pyruvate kinase (PK) is one of the three postulated rate-controlling enzymes of glycolysis. The high-energy phosphate of phosphoenolpyruvate is transferred to ADP by this enzyme, which requires for its activity both monovalent and divalent cations. Enolpyruvate formed in this reaction is converted spontaneously to the keto form of pyruvate with the synthesis of one ATP molecule. PK has four isozymes in mammals M, M2, L, and R. The M2 type, which is considered to be the prototype, is the only form detected in early fetal tissues and is expressed in many adult tissues. This form is progressively replaced by the M( type in the skeletal muscle, heart, and brain by the L type in the liver and by the R type in red blood cells during development or differentiation (M26). The M, and M2 isozymes display Michaelis-Menten kinetics with respect to phosphoenolpyruvate. The Mj isozyme is not affected by fructose-1,6-diphosphate (F-1,6-DP) and the M2 is al-losterically activated by this compound. Type L and R exhibit cooperatively in... 

Fig. 4. Schematic representation of expression of the rat pyruvate kinase (PK) gene. Exons specific to each isozyme are indicated by marked boxes. The exons common to Mj- and M2-type PK and common to L- and R-type PK are shown by open boxes. CAAT, CAT box TATA, TATA box AATAAA, polyadenylation signal.

N10. Noguchi, T., Inoue, H., and Tanaka, T., The M,- and M2-type isozymes of rat pyruvate kinase are produced from the same gene by alternative RNA splicing. J. Biol. Chem. 261,13807-13812 (1986). 

Ul. Uenaka, R., Nakajima, H., Noguchi, T., Imamura, K Hamagauchi, T Tomita, K Yamada, K., Kuwajima, M Kono, N Tanaka, T and Matsuzawa, Y., Compound heterozygous mutations affecting both hepatic and erythrocyte isozymes of pyruvate kinase. Biochem. Biophys. Res. Commun. 208,991-998 (1995). 

Pyruvate kinase-muscle isozyme Muscle-specific phosphorylase kinase Lysosomal acid a-glucosidase... 

Pyruvate kinase is allosterically inhibited by ATP, and the liver isozyme is inhibited by cAMP-dependent phosphorylation. 

Maeda T, Saito T, Harb OS et al (2009) Pyruvate kinase type -II isozyme in Plasmodium falciparum localizes to the apicoplast. Parasitol Int 58(1) 101-105... 

Pyruvate Kinase is also regulated indirectly by PFK. (Note there are other isozymes with differing regulation). 

Pyruvate kinase (note on isozymes) 1. Pyruvate Carboxylase 2. Phosphoenolpyruvate carboxykinase (PEPCK)... 

Flanders, L.E. Schloen, L.H. Sallach, H.J. Isozymes of pyruvate kinase from the grasfrog. Methods EnzymoL, 42C, 166-175 (1975)... 

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