Biochemical pumping

Adrenergic mechanisms have a role in the physiological control of plasma potassium concentration. The biochemical pump that shifts potassium into cells is activated by the P -adrenoceptor agonists (adrenaline, salbutamol, isoprenaline) and can cause hypokalaemia. Pj-adrenoceptor antagonists block the effect. 

Feng Zhou, Andreas Windemuth, and Klaus Schulten. Molecular-dynamis study of the proton pump cycle of bacteriorhodopsin. Biochem., 32(9) 2291-2306, 1993. 

Phosphodiesterase Inhibitors. Because of the complexity of the biochemical processes involved in cardiac muscle contraction, investigators have looked at these pathways for other means of dmg intervention for CHF. One of the areas of investigation involves increased cycHc adenosine monophosphate [60-92-4] (cAMP) through inhibition of phosphodiesterase [9025-82-5] (PDE). This class of compounds includes amrinone, considered beneficial for CHF because of positive inotropic and vasodilator activity. The mechanism of inotropic action involves the inhibition of PDE, which in turn inhibits the intracellular hydrolysis of cAMP (130). In cascade fashion, cAMP-catalyzed phosphorylation of sarcolemmal calcium-channels follows, activating the calcium pump (131). A series of synthetic moieties including the bipyridines, amrinone and milrinone, piroximone and enoximone, [77671-31-9], C22H22N2O2S, all of which have been shown to improve cardiac contractiUty in short-term studies, were developed (132,133). These dmgs... 

Featherstone, C., 1990. An ATP-driven pump for secretion of yeast mating factor. Trends in Biochemical Sciences 15 169—170. 

Oesterhelt, D., and Tittor, J., 1989. Two pumps, one principle Light-driven ion transport in Halobacteria. Trends in Biochemical Sciences 14 57-61. 

A full set of bioreactors with pH and temperature controllers are shown in Figure 1.3. The complete set of a 25 litre fermenter with all the accessory controlling units creates a good opportunity to control suitable production of biochemical products with variation of process parameters. Pumping fresh nutrients and operating in batch, fed batch and continuous mode are easy and suitable for producing fine chemicals, amino acids, and even antibiotics. 

The production rate of acetic acid was 2kg-h 1, where the maximum acetic acid concentration was 12%. Air was pumped into the fermenter with a molar flow rate of 200 moMi-. The chemical reaction is presented in (E. 1.1) and flow diagram in Figure 9.5. Determine the minimum amount of ethanol intake and identify the required mass balance for the given flow sheet. The ethanol biochemical oxidation reaction using A. aceti is ... 

Scheiner-Bobis G (2002) The sodium pump. Its molecular properties and mechanics of ion transport. Eur J Biochem. 269 2424—2433... 

Shin JM, S achs G (2004) Differences in binding properties of two proton pump inhibitors on the gastric H+,K+-ATPase in vivo. Biochem Pharmacol 68 2117-2127... 

Biochemical mechanisms of resistance 3.5 Multidrug resistance pumps... 

To minimize damage due to power outage, the Celanese Corporation in their plant at Newark, N.J., instituted a policy of always generating half its own power. Merck Company installed additional auxiliary steam power to insure constant refrigeration for its biochemicals at its West Point, Pa., plant. At Allied Chemical s phenol plant in Frankfort, Pa., electric devices on air compressors and pumps were replaced by steam-operated controls, and diesel generators were installed to maintain cooling water circulation. 19... 

Shiromani, P. J. Fishbein, W. (1986). Continuous pontine cholinergic microinfusion via mini-pump induces sustained alterations in rapid eye movement (REM) sleep. Pharmacol. Biochem. Behav. 25, 1253-61. 

Chen, Y., Simon, S. M., In situ biochemical demonstration that P-glyco-protein is a drug efflux pump with broad specificity, J. Cell Biol. 2000,... 

The binding of calcium ion to calmodulin, a major biochemical regulator of ion pumps and receptors, occurs on a time scale about a thousand times shorter than that observed for RNA conformational change. This Ca2+-calmodulin binding, which can be followed successfully by nuclear magnetic resonance (NMR), occurs in about ten milliseconds. 

The sodium and calcium pumps can be isolated to near purity and still exhibit most of the biochemical properties of the native pump. Some kinetic properties of these pumps in native membranes are altered or disappear as membrane preparations are purified. For example, when measured in intact membranes, the time-dependencies of phosphorylation and dephosphorylation of the pump catalytic sites exhibit biphasic fast to slow rate transition this characteristic progressively disappears as the membranes are treated with mild detergents. One suggested explanation is that, as the pumps begin to cycle, the catalytic subunits associate into higher oligomers that may permit more efficient transfer of the energy from ATP into the ion transport process [29, 30], Some structural evidence indicates that Na,K pumps exist in cell membranes as multimers of (a 3)2 [31]. 

Eggermont JA, Wuytack F, Verbist J, Casteels R 1990 Expression of endoplasmic-reticulum Ca2+-pump isoforms and of phospholamban in pig smooth-muscle tissues. Biochem J... 

Raeymaekers L, Wuytack F 1996 Calcium Pumps. In Barany M (ed) Biochemistry of smooth muscle contraction. Academic Press, New York, p 241-253 Shull GE 2000 Gene knockout studies of Ca2+-transporting ATPases. Eur J Biochem 267 5284-5290... 

Several of the proteins that mediate Ca2+ flow in and out of SR have been identified. Oxalate-facilitated Ca2+ uptake into the SR and in vitro biochemical studies of purified SR identified it as an ATP-driven Ca2+ pump (SERCA pump reviewed in Himpens et al 1995) that is inhibited by thapsigargin and cyclopiazonic acid and regulated, at least in some smooth muscles, by phosphorylation of phospholamban by cyclic nucleotide-activated protein kinase(s) (Karczewski et al 1998). 

Blostein, R. (1999). Jeanne Mannery Fisher Memorial Lecture 1998. Structure-function studies of the sodium pump, Biochem. Cell Biol., 77, 1-10. 

Nomenclature, 17 384-413 basic scheme of, 17 384-385 biochemical, 17 401-402 computerized approaches to, 17 400-401 elastomer, 21 761t enzyme, 10 258-260 for ionic liquids, 26 840-841 glossaries related to, 17 404 inorganic, 17 387-394 macromolecular (polymers), 17 403 404 organic, 17 394-401 polymer, 20 390-395 pump, 21 88 quinone, 21 236-237 reactor technology, 21 358 related to mass transfer, 15 731-737 reverse osmosis, 21 674-676 Society of Rheology, 21 704 spray-related, 23 199t systematic, 17 394... 

The inhibition of amino-acid transport has been regarded as the main toxic effect of mercury compounds [82], The biochemical mechanism underlying the inhibition is unclear. In unfertilized sea-urchin eggs an interaction with the amino-acid carrier was found, whereas in fertilized eggs inhibition of amino-acid transport was indirect and might result from an elevation of the Na + content of the egg caused by the inhibition of the Na+ pump [83]. The action on the diffusional process could be mediated by an effect on membrane phospholipids or on membrane proteins, or by interaction with Ca2+ which stabilizes membrane structure. Mercuric chloride in skate liver cells inhibited amino acid transport, decreased Na + /K + -ATPase (adenosinetriphosphatase) activity, impaired volume regulatory mechanisms and increased the permeability of the plasma membrane to potassium [84]. It has been suggested that... 

Leier, I., Jedlitschky, G., Buchholz, U., Center, M., Cole, S.P., Deeley, R.G. and Keppler, D. (1996) ATP-dependent glutathione disulphide transport mediated by the MRP gene-encoded conjugate export pump. Biochemical Journal, 314 (Pt 2), 433-437. 

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