Fluorescent probes active

Ji H.F. Dabestani R. Brown G.M. A supramolecular fluorescent probe, activated by protons to detect cesium and potassium ions, mimics the function of a logic gate. J. Am. Chem. Soc. 2000, 122. 9306-9307. 

Kawazoe Y, Shimogawa H, Sato A, Uesugi M (2011) A mitochondrial surface-specific fluorescent probe activated by bioconversion. Angew Chem Int Ed 5(K24) 5478-5481... 

Group II assays consist of those monitoring cellular second messengers. Thus, activation of receptors to cause Gs-protein activation of adenylate cyclase will lead to elevation of cytosolic or extracellularly secreted cyclic AMP. This second messenger phosphorylates numerous cyclic AMP-dependent protein kinases, which go on to phosphorylate metabolic enzymes and transport and regulatory proteins (see Chapter 2). Cyclic AMP can be detected either radiometrically or with fluorescent probe technology. 

Figure 4.7 Changes in intraceiiuiar calcium in cultured rat ventricular myocytes exposed to oxidant stress. Calcium was measured using the fluorescent probe Fura>2. The ratio of the Fura-2 fluorescence measured at 340 and 380 nm excitation is shown and this is proportional to the intracellular calcium concentration. The fast-speed traces shown (note the 3.5 s time-scale) were recorded after various durations of oxidant stress. Myocytes under control conditions (before t = 0) show spontaneous calcium transients. These transients decreased in frequency with oxidant stress until cells failed to show spontaneous activity but continued to maintain a low intracellular calcium.

Wang S, Wang X, Shi W et al (2008) Detection of local polarity and conformational changes at the active site of rabbit muscle creatine kinase with a new arginine-specific fluorescent probe. Biochim Biophys Acta 1784 415 -22... 

DiVittorio KM, Leevy WM, O Neil EJ, Johnson JR, Vakulenko S, Morris JD, Rosek KD, Serazin N, Hilkert S, Hurley S, Marquez M, Smith BD (2008) Zinc(II) coordination complexes as membrane-active fluorescent probes and antibiotics. Chembiochem 9 286-293... 

Since kinases are not hydrolytic enzymes, a small molecule-based FRET probe does not seem to be a straight forward solution for this enzyme activity. Nevertheless, quite a number of fluorescent probes based on small substrate peptides have been prepared in... 

Blum, G., Mullins, S. R., Keren, K., Fonovic, M., Jedeszko, C., Rice, M. J., Sloane, B. F. and Bogyo, M. (2005). Dynamic imaging of protease activity with fluorescently quenched activity-based probes. Nat. Chem. Biol. 1, 203-209. 

Mizukami, S., Kikuchi, K., Higuchi, T., Urano, Y., Mashima, T., Tsuruo, T. and Nagano, T. (1999). Imaging of caspase-3 activation in HeLa cells stimulated with etoposide using a novel fluorescent probe. FEBS Lett. 453, 356-360. 

Weissleder, R., Tung, C. H., Mahmood, U. and Bogdanov, A., Jr. (1999). In vivo imaging of tumors with protease-activated near-infrared fluorescent probes. Nat. Biotechnol. 17, 375-378. 

Caturla, F., Enjo, J., Bemabeu, M. C. and Le Serre, S. (2004). New fluorescent probes for testing combinatorial catalysts with phosphodiesterase and esterase activities. Tetrahedron 60, 1903-1911. 

SAMSA-fluorescein, 5- [2(and 3)-5-(acetylmercapto)-succinoyl]amino fluorescein, is a fluorescent probe containing a protected sulfhydryl group. In its protected state, the compound is unre-active. The acetyl-protecting group can be removed by treatment with dilute NaOH at pH 10.0 (Figure 9.9). The resulting free sulfhydryl derivative can be used to label thiol-reactive crosslinkers or to couple with sulfhydryl residues on proteins and other molecules. After activating... 

Conjugates of (strept)avidin with these fluorescent probes may be prepared by activation of the phycobiliprotein with N-succinimidyl 3-(2-pyridyldithio)propionate (SPDP) to create a sulf-hydryl-reactive derivative, followed by modification of (strept)avidin with 2-iminothiolane or SATA (Chapter 1, Section 4.1) to create the free sulfhydryl groups necessary for conjugation. The protocol for SATA modification of (strept)avidin can be found in Section 3.1, this chapter. The procedure for SPDP activation of phycobiliproteins can be found in Chapter 9, Section 7. Reacting the SPDP-activated phycobiliprotein with thiol-labeled (strept)avidin at a molar ratio of 2 1 will result in highly fluorescent biotin binding probes. 

Microelectronics arrays [8] Probes are drawn by electric current to chip surface Number of genes is dependent on the number of electrodes that can be made onto the surface of the array Fluorescent tag labeling and fluorescent detection Active Nanogen... 

Most work on the SR and diseased smooth muscle has concerned vascular smooth muscle in hypertensive animals, and bladders from animal models of outflow obstruction. The tools used to study SR function are mainly indirect, and include recording tension or intracellular [Ca2+] with fluorescent probes, measuring Ca2+ fluxes with 45Ca, and investigating the effects of drugs known to block SERCA or activate store release. More directly, some measurement of the activity of SERCA in microsomal preparations has been undertaken (e.g. Zderic et al 1996). 

The microenvironment of the micellar core inferred from fluorescent probes is said to be similar to some organic media (Turner and Brand, 1968 Cordes and Gitler, 1973). Similar conclusions have been obtained by other spectroscopic means (see previous sections). The active site of an enzyme is usually quite hydrophobic and the number of water molecules at the active site is limited. Therefore, it is very useful to study the behavior of the catalytic groups in organic media in relation to micellar and enzymatic catalysis. 

The aqueous cores of reverse micelles are of particular interest because of their analogy with the water pockets in bioaggregates and the active sites of enzymes. Moreover, enzymes solubilized in reverse micelles can exhibit an enhanced catalytic efficiency. Figure B4.3.1 shows a reverse micelle of bis(2-ethylhexyl)sulfosuccinate (AOT) in heptane with three naphthalenic fluorescent probes whose excited-state pK values are much lower than the ground-state pK (see Table 4.4) 2-naphthol (NOH), sodium 2-naphthol sulfonate (NSOH), potassium 2-naphthol-6,8-disulfonate (NSOH). The spectra and the rate constants for deprotonation and back-recombination (determined by time-resolved experiments) provide information on the location of the probes and the corresponding ability of their microenvironment to accept a proton , (i) NDSOH is located around the center of the water pool, and at water contents w = [H20]/[A0T] >... 

Ion recognition by fluorescent probes is a field in which the word design takes its full sense, and there is no doubt that it will remain an active field of research for several decades. 

L. B. Cohen, B. M. Salzberg, H. V. Davila, W. N. Ross, D. Landowne, A. S. Waggoner, and C. H. Wang, Changes in axon fluorescence during activity Molecular probes of membrane potential, J. Membrane Biol. 19, 1 (1974). 

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