ADP—See Adenosine 5 -diphosphate

The sugar nucleotides (an uninformative name that has been used for glycosyl nucleotides, or more strictly, glycosyl esters of nucleoside di- or mono-phosphates) were discussed in this Series12 in 1973. Since then, accumulation of new data about these derivatives has continued, and now, about 35 representatives of this class are known to participate in the biosynthesis of polysaccharide chains of bacterial polymers (for a survey, see Ref. 13). These include glycosyl esters of uridine 5 -diphosphate (UDP), thymidine 5 -diphosphate (dTDP), guanosine 5 -diphosphate (GDP), cytidine 5 -diphosphate (CDP), cytidine 5 -monophosphate (CMP), and adenosine 5 -diphosphate (ADP). 

Abbreviations used NAD+ = nicotinamide adenine dinucleotide NADH e reduced nicotinamide adenine dinucleotide NADP = nicotinamide adenine dinudeotide phosphate NAD PH reduced nicotinamide adenine dinucleotide phosphate NMN, NMN+ nicotinamide mononucleotide NMNH2 = reduced nicotinamide mononucleotide a-NAD a-nicotinamide adenine dinucleotide AMP = 5 -adenylic acid 3,5 -AMP adenosine 3, 5 -cycIic phosphate 3 ,5 -UMP = uridine 3, 5 -cyclic phosphate 3, 5 -CMP cytidine 3, 5-cyclic phosphate 3 f5 GMP = guanosine 3 5f-cyclic phosphate 3, 5 TMP thymidine 3, 5 -cyclic phosphate Dibutyryl-3, 5 -AMP = N6,02-dibutyryladenosine 3, 5 -cyclic phosphate 2, 3 -UMP = uridine 2 ,3 -cyclic monophosphate 2, 3 -CMP cytidine 2, 3 -cyclic monophosphate 2, 3 -AMP = adenosine 2, 3 -cyclic monophosphate 2 ,3 -GMP = guanosine 2 3 -cyclic monophosphate 2 -UMP = uridine 2 -phosphate -UMP uridine -phosphate 5 -UMP = uridine 5 phosphate Poly U polyuridylic acid ADP = adenosine 5 -diphosphate FAD = flavin adenine dinucleotide UpA, UpU, ApU and ApA x dinucleoside phosphates of uridine and/or adenine. c See original references for experimental conditions and additional data. 

Figure 4.30 Flourescence binding competition, (a) Structure of dial-mant-Ap4A probe, (b) Fluorescence binding data when two different proteins are incubated with the probe in the presence and absence of putative site-specfic competitive binders. In the case of LysU protein (see Chapters 6, 7 and 8), adenosine 5 -diphosphate (ADP) and adenosine 5 -triphosphate (ATP) are competitive binders and reduce probe binding to basal levels. In the case of molecule chaperone protein GroEL (see Chapters 6 and 7) the probe is binding allosteric to adenosine 5 -diphosphate (ADP) and adenosine 5 -[X,-methylene]-triphosphate (AMPPCP) (Reproduced from Wright et al., 2006, Fig. 2c).

The chemistry of phosphate esters is rich and varied. Phosphate esters are important in biological systems. The phosphate ester of a nucleoside (a nucle-obase attached to a ribose derivative see Chapter 28, Section 28.5) is called a nucleotide. These are structural components used in DNA and RNA. Using adenosine (210) as an example, there are three possible monophosphate esters 211, 212, and 212. The pyrophosphate (diphosphate) derivative is adenosine 5 -diphosphate (214). The symbol A is used to designate an adenosine derivative in biology, so 211 is abbreviated 5 -AMP (adenosine 5 -monophosphate) and 214 is 5 -ADP (adenosine 5 -diphosphate). The numbering is explained in Chapter 28, Section 28.5. 

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.

Adenosine 5 -phosphate. See AMP Adenosine diphosphate. See ADP Adenosine monophosphate. See AMP Adenosine triphosphate. See ATP Adenosine-diphosphate-ribose. See ADP-ribose... 

Adenosine, chemical stnicture, 14 Adenosine diphosphate, see ADP Adenosine triphosphate, see ATP 5-Adenosylho(mocysteine (SAH), 497 5-Adenosylmethi(mme SAM), 201,314, 497,898... 

Figure 1.4 Compaitmentation of biosynthesis and sequestration. Abbreviations SM, secondary metabolites CS-SM, conjugate of SM with glutathione NPAAs, non-protein amino acids ATP, adenosine triphosphate ADP, adenosine diphosphate mt, mitochondrion cp, chloroplast nc, nucleus 1, passive transport 2, free diffusion 3, H+/SM antiporter 4, ABC transporter for SM conjugated with glutathione 5, ABC transporter for free SM 6, H+-ATPase. (See Plate 3 in colour plate section.)...

Platelets release adenosine diphosphate (ADP) and serotonin (5HT, 5-hydroxytrypta-mine) following adhesion. 5HT is a powerful vasoconstrictor, which reinforces constriction of blood vessels reducing blood flow and loss. ADP attracts more platelets. The platelets fuse together into an inseparable mass. As this happens, large amounts of thromboxane A2 are released, which further enhances aggregation and is also a potent vasoconstrictor (see Figure 7.1). 

The number of known protein structures that contain a small molecule ligand is still quite limited. Among them, the adenosine and guanosine diphosphate fragments (Figure 13.15) are found most frequently, usually as part of a cofactor (e.g. NAD, NADP, FAD, ADP, GDP, ATP, see Scheme 13.5 32 examples [74]). Ninety corresponding monophosphate fragments are available for comparison in the CSD [75]. TVvelve of these are di- and triphosphates. 

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