Creatine-phosphate

NAPHTHALENE DERIVATIVES] (Vol 16) a-Napthol-creatine phosphate-diacetyl... 

Clinical Analysis. A wide range of clinically important substances can be detected and quantitated using chemiluminescence or bioluminescence methods. Coupled enzyme assay protocols permit the measurement of kinase, dehydrogenase, and oxidases or the substrates of these enzymes as exemplified by reactions of glucose, creatine phosphate, and bile acid in the following ... 

Fig. 4. Requirements, substrates, and products of Mo-nitrogenase catalysis, where I is the MoFe protein II the Fe protein and Pi is inorganic phosphate. The generating system is composed of creatine phosphate and creatine phosphokinase to recycle the inhibitory MgADP produced during catalysis to...

Sodium creatine phosphate (4H2O) [922-32-7] M 327.1. See creatine phosphate di-Na salt on p. 523 in Chapter 6. 

Creatine phosphate di Na, 4H2O salt (phosphocreatine) [922-32-7] M 327.1, pK, 2.7, pK 4.58, pKj - 12. To 3-4g of salt in H2O (220mL) is added 4 vols of EtOH with thorough stirring and allowed to stand at 20° for 12hrs (this temp is critical as crystals did not readily form at 23° or 25°). The salt first appears as oily droplets which slowly settle and crystallise. After 12hrs the supernatant is clear. Stirring... 

Draw all possible resonance structures for creatine phosphate and discuss their possible effects on resonance stabilization of the molecule. 

Write the equilibrium constant, for the hydrolysis of creatine phosphate and calculate a value for at 25°C from the value of AG° in Table 3.3. 

FIGURE 14.21 The structures of creatine and creatine phosphate, guanidiniutn compounds that are important in muscle energy metabolism. 

Muscles contain enough creatine phosphate to power contraction for about ten seconds. 

In resting muscle the high concentration of ADP does not decrease the proton gradient effectively and the high membrane potential slows electron transport. ADP, formed when ATP is hydrolyzed by myosin ATPase during contraction, may stimulate electron transport. However, the concentration of ATP (largely as its Mg salt) is buffered by its readily reversible formation from creatine phosphate catalyzed in the intermembrane space, and in other cell compartments, by the various isoenzymes of creatine kinase (reviewed by Walliman et al., 1992). 

Storey, K.B. Hochachka, P.W. (1974). Activation of muscle glycolysis A role for creatine phosphate in phosphofructokinase regulation. FEES Lett. 46, 337-339. 

The Creatine Phosphate Shuttle Facilitates Transport of High-Energy Phosphate From Mitochondria... 

Figure 12-14. The creatine phosphate shuttle of heart and skeletal muscle. The shuttle allows rapid transport of high-energy phosphate from the mitochondrial matrix into the cytosol. CKg, creatine kinase concerned with large requirements for ATP, eg, muscular contraction CIC, creatine kinase for maintaining equilibrium between creatine and creatine phosphate and ATP/ADP CKg, creatine kinase coupling glycolysis to creatine phosphate synthesis CK, , mitochondrial creatine kinase mediating creatine phosphate production from ATP formed in oxidative phosphorylation P, pore protein in outer mitochondrial membrane.

Figure 31-3. Arginine, ornithine, and proline metabolism. Reactions with solid arrows all occur in mammalian tissues. Putrescine and spermine synthesis occurs in both mammals and bacteria. Arginine phosphate of invertebrate muscle functions as a phosphagen analogous to creatine phosphate of mammalian muscle (see Figure 31-6).

Creatinine is formed in muscle from creatine phosphate by irreversible, nonenzymatic dehydration and loss of phosphate (Figure 31-6). The 24-hour urinary excretion of creatinine is proportionate to muscle mass. Glycine, arginine, and methionine all participate in creatine biosynthesis. Synthesis of creatine is completed by methylation of guanidoacetate by S-adenosylmethio-nine (Figure 31-6). 

Creatine Phosphate Constitutes a Major Energy Reserve in Muscle... 

Creatine phosphate prevents the rapid depletion of ATP by providing a readily available high-energy phosphate that can be used to regenerate ATP from ADP. 

Creatine phosphate is formed from ATP and creatine (Figure 49-16) at times when the muscle is relaxed and demands for ATP are not so great. The enzyme catalyzing the phosphorylation of creatine is creatine kinase (CK), a muscle-specific enzyme with clinical utility in the detection of acute or chronic diseases of muscle. 

A Sprinter Uses Creatine Phosphate Anaerobic Glycolysis to Make ATP, Whereas a Marathon Runner Uses Oxidative Phosphorylation... 

Creatine phosphate is the major energy source during the first 4-5 seconds. ATP is the major energy source throughout. 

Two major types of muscle fibers are found in humans white (anaerobic) and red (aerobic). The former are particularly used in sprints and the latter in prolonged aerobic exercise. During a sprint, muscle uses creatine phosphate and glycolysis as energy sources in the marathon, oxidation of fatty acids is of major importance during the later phases. Nonmuscle cells perform various types of mechanical work carried out by the structures constituting the cytoskeleton. These strucmres include actin filaments (microfilaments), micrombules (composed primarily of a- mbulin and p-mbulin), and intermediate filaments. The latter include keratins, vimentin-like proteins, neurofilaments, and lamins. 

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