Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.4.1.18 (branching enzyme)
 628 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of 2-methoxy-6-alkyl(C19-C25)benzoquinones-1,4 and 4-methoxy-6-alkyl(C19-C25)benzoquinones-1,2 on the respiration of isolated rat liver mitochondria has been studied. As a concentration of each of the quinones increased gradually from zero, the rate of the respiration using NAD-dependent substrates firstly increased but then decreased, 1,2-quinones being the more potent inhibitors. Concurrently, the respiratory control of mitochondria was lowered, indicating uncoupling effect of these quinones. With succinate the latter exhibited moderately accelerating effect. Uncoupled by 2,4-dinitrophenol, the respiration was stimulated by the both preparations in the presence of succinate but was suppressed when NAD-dependent substrates were used. The observed inhibitory effects have been assumed to be caused by a competition between the quinones and endogenous co-enzyme Q for the active site of NADH-dehydrogenase complex of the respiratory chain.
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PMID:[The effect of isomeric alkyl (C19--C25) methoxybenzoquinones on mitochondrial respiration]. 130 55

Inclusion bodies containing glycogen-enzymes were found in 30 to 60% of type 2 fibres of tenotomized calf muscles (m. gastrocnemius, m. soleus, m. plantaris) in rats, using histochemical reactions. The bodies appeared within 1 week after the tenotomy and were localized both in the central and the subsarcolemmal regions and rarely extruded into the extracellular space. These aggregates are 3 to 15 microns in length and 2 to 11 microns in diameter. In addition to glycogen, these bodies also contained various enzymes of the glycogen metabolism such as phosphorylase, a branching enzyme, and glucose-6-phosphatase, but showed no NADH-reductase, lactate dehydrogenase, or myofibrillar ATP-ase activity. The results indicate that glycogen-enzymes containing bodies are a degenerative phenomenon, which occurs only in type 2 fibres of the tenotomized muscles.
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PMID:Glycogen-enzymes containing bodies in type 2 fibres of tenotomized muscles in the rat. 255 27

This paper reviews the development in the 1950s of methods to determine the redox states of the free [NAD(+) ]/[NADH] in cytoplasm of yeast by Helmut Holzer and Feodore Lynen and in rat liver by Theodore Bucher and Martin Klingenberg. This work was extended in the 1960s in the laboratory of Hans Krebs, where the use of basic thermodynamic and kinetic principles allowed the extension of this approach to the determination of the free mitochondrial [NAD(+) ]/NADH] in mitochondria and the redox state of the free NADP system in cytoplasm and mitochondria. This work also outlined the linkage between the redox states in the various couples to the phosphorylation state or the free [ATP]/[ADP][P(i) ] ratio, the central energy parameter of living cells. This work has since been extended to include other energy-linked systems including the gradients of inorganic ions between extra and intracellular phases of the cell and the redox state of the co-enzyme Q couple of mitochondria. This system of linked near-equilibrium redox and phosphorylation potentials constitutes a framework of primitive metabolic control that is altered in a number of disease phenotypes. The alteration of such disease phenotypes by substrate availability is discussed, as well as the importance of a thorough grounding in basic kinetics and thermodynamics in designing new therapies to normalize the metabolic abnormalities that are the proximate cause of many common and some rare diseases states.
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PMID:The determination of the redox states and phosphorylation potential in living tissues and their relationship to metabolic control of disease phenotypes. 2163 66