Guanosine 5’-monophosphate GMP

Furthermore, 13C NMR data allow one to determine the self-association of nucleotides, as was reported for disodium guanosine 5 -monophosphate (5 -GMP) With increasing concentration of 5 -GMP all purine carbon signals shift upfield, which is interpreted in terms of stack formation [753, 762]. 

Using 15N-edited one-dimensional H-NMR spectroscopy and 2D [1H,15N] HMQC-NMR spectroscopy, reactions between 15N-labelled cis-PtCl2(NH3)2 and guanosine 5 -monophosphate (5 -GMP) have been studied in aqueous solutions [17]. The short-lived aqua-chloro intermediate is detectable during the early stages, followed by the formation of the mono- and... 

Kinetic studies on reactions of Pt(II) complexes with biologically relevant nucleophiles have been reported. The substitution of both coordinated water molecules by a series of nucleophiles (namely, thiourea (tu), L-methionine (L-Met), and guanosine-5 monophosphate (5 -GMP)) was investigated as a function of concentration, temperature, and pressure using stopped-fiow techniques and was found to occur in two subsequent reaction steps. The activation parameters for all reactions suggest an associative substitution mechanism. 

Fig. 3.8. A schematic presentation of the effect of nitric oxide on the relaxation of smooth muscles. GTP, guanosine 5 -triphosphate 5 -GMP, guanosine 5 -monophosphate cGMP, cyclic guanosine 3, 5 -monophosphate...

The tri-n-butylammonium salt of guanosine 5 -monophosphate (TBA-GMP) was prepared by passing a solution of 1 g of the disodium salt of GMP in 40 ml of 50% aqueous methanol through a Dowex 50W-X8 column in the pyridinium form. The solvent was evaporated under reduced pressure, and the residue was dissolved in 40 ml of 50% aqueous methanol and TEA (0.5 ml). The solvent was evaporated again, and excess TEA was removed by shaking the residue with pentane. The TBA-GMP was dried by dissolution in dry pyridine-dimethylformamide (1 1, v/v), followed by evaporation of the solvent under reduced pressure. This procedure was repeated three times. To obtain [ H] APh-GDP, [ HjGMP (Amersham) was added to TBA-GMP before drying. 

In addition, vinpocetine selectively inhibits a specific calcium, calmodulin-dependent cycHc nucleotide phosphodiesterase (PDF) isozyme (16). As a result of this inhibition, cycHc guanosine 5 -monophosphate (GMP) levels increase. Relaxation of smooth muscle seems to be dependent on the activation of cychc GMP-dependent protein kinase (17), thus this property may account for the vasodilator activity of vinpocetine. A review of the pharmacology of vinpocetine is available (18). 

Emission quenching is also observed with mononucleotides. In that case the quenching efficiency decreases from GMP (guanosine 5 monophosphate) to AMP (adenosine 5 monophosphate) i.e. it also follows the redox potentials of the bases, as G is more easily oxidisable than A, although the oxidation potential valura reported in the literature are rather different from one author to the other [101-104], Moreover the quenching rate constant by GMP in a Kries of different TAP and HAT complexes plotted versus the reduction potential of the excited state (Fig. 12) [95] is consistent with an electron transfer process. Indeed, as will be demonstrated in Sect. 4.3.1, these quenchings (by the mono-and polynucleotides) originate from such processes. 

E Glutamic acid, glutamate, or glutamyl GMP Guanosine 5 -monophosphate... 

The mechanism of the action of nitrates is not completely known, though it is reasonably likely that within smooth muscle cells, nitrates are transformed into nitrites, which then release NO. This, in turn, reacts with guanylatecyclase, causing increased synthesis of guanosine 3, 5 -monophosphate (cyclic GMP). As a result, a GMP-requiring protein kinase is activated, which results in less phosphorylation of muscle protein. Dephosphorylated muscle proteins are less able to contract, which ultimately results in a reduction of the heart s need for oxygen. 

Gly-R, glycine receptor GMP, guanosine 5 -monophosphate GNDF, glial cell line-derived neurotrophic factor... 

Incubates of platinum complexes with guanosine 5-monophosphate (GMP)... 

---