P phosphorylation

As shown in Fig. 1, the function of E-III is to transfer the phosphoryl group from P-HPr to E-II. P-phosphorylated peptides have been isolated from a number of E-III species and A domains of S. carnosus and S. aureus IIl [27], E. coli II [28],... 

Huganir, R.L., Delcour, A.H., Greengard, P., Hess, G.P. Phosphorylation of the nicotinic acetylcholine receptor regulates its rate of desensitization. Nature. 321 774, 1986. 

Determination of electrochemical oxidation potentials and electrochemical reduction of 13 p-phosphorylated acyclic nitrones shows that phosphorylated compounds have a clear anodic shift of potentials of both, oxidation (Ep 1.40 to 2.00 V versus SCE in CH3CN) and reduction (Ep—0.94 to —2.06 V). This is caused by a strong electron-acceptor influence of the diethoxyphosphoryl group (430). In contrast, a reversible one-electron oxidation of azulene nitrones (233) (Scheme 2.80) occurs 0.6 V below the Ep potential of PBN, that is at the value one observes the oxidation of AH -imidazole-1,3-dioxides (219) (428, 429). In other words, the corresponding RC (234) is 14 kcal more stable than the RC of PBN. Although the EPR spectrum of RC (234) was not recorded, RC (236) from dinitrone (235) turned out to be rather stable and gave an EPR spectrum (170). 

Rondinone, C.M. Carvalho, E. Rahn, T. Manganiello, V.C. Degerman, E. Smith, U.P. Phosphorylation of PDE3B by phosphatidylinositol 3-kinase associated with the insuhn receptor. J. Biol. Chem., 275, 10093-10098 (2000)... 

Saier, M.H. Schmidt, M.R. Lin, P. Phosphoryl exchange reaction catalyzed by enzyme I of the bacterial phosphoenolpyruvate sugar phosphotransferase system. Kinetic characterization. J. Biol. Chem., 255, 8579-8584 (1980)... 

In the medium and large neurofilament chains, where there are numerous K-S-P phosphorylation sites in the tail domains, the effect of phosphorylation is quite different. It has no visible effect on the state of filament assembly. It does, however, appear to be particularly important in determining axonal diameter (and concomitant conduction velocity), as well as transport properties and association with other cytoskeletal components. Experimentally, numerous phosphorylation sites have been shown to exist in a wide variety of IF proteins. Many others have been proposed on the basis of sequence motifs consistent with sites of known kinases. It has also been shown that mutations in which phosphorylation sites have been changed (see, for example, S35A in keratin 19) lead to various pathologies, including malformations in the filament assembly. 

Figure 2.2 Proposed mechanism of inducible gene expression mediated by heat shock and certain other pathophysiological conditions. Adapted from Zou et al. (1998). Terminology HSF1 (heat shock factor 1) HSP (heat shock proteins) HSE (heat shock element in DNA) P (phosphorylation).

Figure 2. Schematic representation of the activation of the cdk4/cyclin D complex during Gl. Evidence shows that CaMKIa, which can be activated by either CaMKKa or (3, activates the cdk4/cyclin D complex, leading to the phosphorylation of Rb and therefore de-repression of E2F transcription factor members. The mechanism by which CaMKI regulates cdk4/cyclin D remains to be determined. GFR, receptor for a growth factor CAK, cdk activating kinase p21/p27, members of the inhibitory Cip and Kip families, respectively E2F 1-3, transcription factors 1-3 of die E2F family Rb, Retinoblastoma protein P, phosphorylation event...

Figure 23 Regulatory network of growth and development mediated by cytokinin. Arrows and blunted lines indicate positive and inhibitory interactions, respectively solid lines show direct molecular interactions and dashed lines show interactions that are indirect. H, His residues D, Asp residues encircled P, phosphoryl group.

Cell line expressing oncogenic KRAS, Cell lines A549, human lung adenocarcinoma CaLu-1, human nonsmaU cell lung cancer MDA-MB-231, human breast cancer PANC-1, human pancreatic cancer MMTV, mouse mammary tumor virus n/d, not determined p-, phosphorylated form of a protein. 

Intermediates formed from G3P are utilized (Fig. 1) via a series of isomerizations, condensations and rearrangements resulting in the conversion of five molecules of triose phosphate to three of pentose phosphate, eventually ribulose 5-phosphate (Rbu-5-P). Phosphorylation of Rbu-5-P with ATP regenerates the original carbon acceptor Rbu-1,5-P2, thus completing the cycle. 

Yurchenko, R.L, Klepa, T.L, Lozovitskaya, O.V., and Tikhonov, V.P., Phosphorylated adamantanes. Part 5. Some reactions of adamantane-containing dialkyl hydrogen phosphites, Zh. Obshch. Khim., 53, 2445, 1983 J. Gen. Chem. USSR (Engl. Transl.), 53, 2206, 1983. 

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