Adenosine diphosphate , labeled

A good example of an affinity label for creatine kinase has been presented (35). This enzyme catalyzes the reversible transfer of a phosphoryl group from adenosine triphosphate [56-65-5] (17) to creatine [57-00-1] (18), leading to adenosine diphosphate [7584-99-8] (19) and phosphocreatine [67-07-2]... 

Beyer, K., and Nuscher, B., 1996, Specific cardiolipin binding interferes with labeling of sulfhydryl residues in the adenosine diphosphate/adenosine triphosphate carrier protein from beef heart mitochondria, Biochemistry 35 15784-15790. 

The oxygen formed clearly comes from H20 and not from C02, because photosynthesis in the presence of water labeled with lgO produces oxygen labeled with 180, whereas carbon dioxide labeled with 180 does not give oxygen labeled with 180. Notice that the oxidation of the water produces two electrons, and that the formation of NADPH from NADP requires two electrons. These reactions occur at different locations within the chloroplasts and in the process of transferring electrons from the water oxidation site to the NADP reduction site, adenosine diphosphate (ADP) is converted to adenosine triphosphate (ATP see Section 15-5F for discussion of the importance of such phosphorylations). Thus electron transport between the two photoprocesses is coupled to phosphorylation. This process is called photophosphorylation (Figure 20-7). 

Fig. I. Bromo-2,3-dioxobutyl nucleotide affinity labels, (a) 2-(4-Bromo-2,3-dioxobutylthio)-adenosine S -diphosphate (b) 6-(4-bromo-2,3-dioxobutylthio)adenosine S -dipho phate and (c) 8-(4-bromo-2,3-dioxobutylthio)adenosine S -diphosphate.

Figure 10 Chemical structures of adenosine 5 -monophosphate (n = 1 AMP ), adenosine 5 -diphosphate (n = 2 ADP "), and adenosine 5 -triphosphate (n = 3 ATP ) as well as of cytidine 5 -monophosphate (n = 1 CMP, cytidine 5 -diphosphate (n = 2 CDP ), and cytidine 5 -triphosphate (n = 3 CTP ) in their dominating anti conformation [11-14,50]. Note, the triphosphate chain in nucleoside 5 -triphosphates (NTP ) is labeled a, P, and y, where y refers to the terminal phosphate group (see also Figure 9) for nucleoside 5 -diphosphates (NDP ) the situation is analogous with a and P (see Figure 9). The adenine and cytosine residues in the nucleotide structures shown above may be replaced by one of the other nucleobase residues shown in Figiue 1 if this substitution is done in the way the bases are depicted within the plane (Figure 1), then the anti conformation will also result for the corresponding nucleoside 5 -phosphates. The abbreviations AMP, ADP , ATP , IMP, etc. in this text always represent the 5 -derivatives 2 - and 3 -derivatives are defined by 2 AMP, 3 AMP, etc. in a few instances where uncertainties might otherwise occur, the abbreviations 5 AMP , 5 ADP , etc. are also used.

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