Adenosine triphosphate Adrenaline

Adenosine triphosphate, coupled reactions and. 1128-1129 function of, 157, 1127-1128 reaction with glucose, 1129 structure of, 157, 1044 S-Adenosylmethionine, from methionine, 669 function of, 382-383 stereochemistry of, 315 structure of, 1045 Adipic acid, structure of, 753 ADP, sec Adenosine diphosphate Adrenaline, biosynthesis of, 382-383 molecular model of, 323 slructure of, 24... 

The vesicles of the adrenal gland concentrate adrenaline by a factor of at least 106 and adenosine triphosphate by a factor of 102, whereas they do not concentrate K Na+, Mg2+, Cl , and other phosphates. How is the selectivity achieved ... 

Many of these effects can be explained by an interference with a central signal cascade (Fig. 5.195). Adrenaline activates adenylylcyclase, which converts adenosine triphosphate (ATP) into cyclic 3 ,5 -adenosine monophosphate (cAMP). This is a secondary messenger, which is deactivated by a phosphodiesterase to adenosine monophosphate (AMP). Dephosphorylation with a 5 -nucleotidase releases the neuromodulator adenosine, which is enriched extracellularly in the waking state and is degraded during sleep. When adenosine binds in the presynaptic cleft to adenosine-Aj-receptors of the nerve cells, the release of most neurotransmitters, like glutamate, y-aminobutyric acid, norephedrine, serotonin and acetylcholine is inhibited. In addition, adenosine inhibits adenylylcyclase. 

Acrylic fiber, 213 ACTH, 162,214 Activity series, 249 Adams, Roger, 130, 208 Addition reaction, 209 Adenine, 141, 178 Adenosine diphosphate see ADP Adenosine triphosphate see ATP Adiabatic calorimeter, 172 ADP, 137, 140, 165 Adrenaline, 163, 177, 206 Adrenocorticotrophic hormone see ACTH... 

Adenosine triphosphate seems to be of importance for the binding of serotonin, for that of noradrenaline and adrenaline adenosine triphosphate (385, 948, 949, 960, 961,1471) rfbonucleic acid, and for the binding of... 

Adenosine triphosphate is the specific nucleotide of this reaction. Active methionine is the methyl donor to various acceptors, e.g., nicotinamide, glycocyamine, adrenaline. Transmethylations are catalyzed by specific methylpherases The product of transmethylation is usually the iV-methyl derivative of the acceptor while active methionine is converted to (S-adenosylhomocysteine. Active methionine may undergo hydrolytic cleavage in yeast to yield 5 -methylthioadenosine and homoserine 96). The reaction may not be enzymic. This adenosine derivative had been isolated long before active methionine was known 96). Betaine and certain sul-fonium compounds structurally related to active methionine, e.g., dimethyl-/8-propiothetin [(CHs)2= S—CH —CHj—COOH] 97), can also act as methyl donors for homocysteine in liver suspensions 98). 

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