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Thiol-containing amino acids

If the nitrosothiol is made from a naturally-occurring thiol-containing amino acid the S-nitrosothiol should be the perfect agent for the study of nitrovasodilation. The product, other than NO (i.e. the disulfide), is also a naturally occurring substance, and S-nitrosothiols themselves occur naturally [13]. Release of NO occurs at room... [Pg.204]

Many starfish cause an escape response in usually sessile marine invertebrates [7]. The starfish Dermasterias imbricata causes the sea anemone Stomphia coccinea to release its basal disc from the substratum and swim away on contact. Bioassay-directed fractionation of the starfish extract led to the isolation of the compound found to elicit this response, the benzyltetrahydroisoquinoline alkaloid imbricatine (646). The structure of compound 646 was elucidated by spectral data interpretation. The amino acid residue in imbricatine is related to the thiol containing amino acids ovothiols A-C. Imbricatine (646) is active in both LI210 and P388... [Pg.717]

A,A-dialkyldithiocarbamates produce stable, square-planar rhodium(II) complexes of the type [Rh(S2CNR2)2] (R = Me, Et) similar anionic hfr(maleonitriledithiolate) are also known. Neutral complexes are formed by the thiol containing amino acids cysteine, methyl cysteine, or penicillamine. It is noteworthy that these paramagnetic [Rh(aminoacid)2] complexes can easily be prepared from dimeric, diamagnetic [Rh(02CMe)2MeOH]2. ... [Pg.4064]

A better understanding of certain physiological and biochemical processes affecting mercury kinetics may help explain these species differences. Specific processes that appear likely determinants include differences in demethylation rates affecting methylmercury fecal secretion, reabsorption, and membrane transport (Farris et al. 1993) differences in tissue glutathione content and renal -glutamyltranspeptidase activity (Tanaka et al. 1991, 1992), differences in antioxidative status (Miller and Woods 1993), differences in plasma cysteine concentrations compared with other thiol-containing amino acids (Aschner... [Pg.245]

Aschner, M., and T.W. Clarkson. 1987. Mercury 203 distribution in pregnant and nonpregnant rats following systemic infusions with thiol-containing amino acids. Teratology 36(3) 321-328. [Pg.118]

Covalent bonds between the thiol-containing amino acids. Two of the polar cysteines can be oxidized to a dimeric amino acid called cystine (Figure 19.10). The disulfide bond of cystine can be a cross-link between different proteins, or it can tie two segments within a protein together. [Pg.570]

Hart, J. J., Welch, R. M., Norvell, W. A., and Kochian, L.V., Measurement of thiol-containing amino acids and phytochelatin (PC2) via capillary electrophoresis with laser-induced fluorescence detection. [Pg.902]

He Q-Q, Fang G-M, Liu L (2013) Design of thiol-containing amino acids for native chemical ligation at non-Cys sites. Chin Chem Lett 24 265-269... [Pg.259]

Thiol-containing amino acids, such as cysteine and penicillamine, are readily oxidised at mercury electrodes. The use of this reaction to measure them is discussed in detail in Chapter 5. [Pg.18]

An amino acid analyser with post-column ninhydrin detection can give specific and accurate measurement of sulfur-containing amino acids, such as cystine in plasma and urine. However, analysis times are long (hours) and thiol-containing amino acids, such as cysteine, cannot be measured since the necessary elevated column temperatures lead to their rapid oxidation. In an attempt to circumvent this problem, Brigham et al. derivatised cysteine with iodoacetate to give the stable analyte S-carboxymethylcysteine. Subsequently, A-ethylmaleimide and iodoacet-amide have been used to derivatise amino-thiols prior to amino acid analysis. [Pg.83]

Protection of Thiols as Disulfides. The protection of free thi ols as unsymmetrical ethyl disulfides can be efficlentiy performed with 5-ethyl ethanethiosulfinate In high yield. The advantages of this protocol are (I) It operates with a very inexpensive starting material (ii) it can be performed on a wide variety of substrates such as protected and unprotected thiol containing amino acids... [Pg.281]

MWCNT electrodes have been developed to monitor the electrochemical oxidation of insulin, a pancreas-produced hormone that plays a key role in the regulation of carbohydrates and fat metabolism in the body. This provides a possible method to evaluate the quality of pancreatic islets before their transplantation. By coating similar MWCNT electrodes with platinum microparticles, thiols containing amino acids can be detected in rat striatal that is the subcortical part of the fore-brain. CNT-based sensors can be incorporated into flexible biocompatible substrates to facilitate in vivo sensing. For instance, free cholesterol in blood can be measured using MWCNT electrodes placed on a biocompatible substrate whereas flexible pH sensors can be formed from polyaniline (a conductive polymer) and nanotube composites. ... [Pg.229]


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See also in sourсe #XX -- [ Pg.35 ]




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Acids containing

Amino acids containing

Amino thiols

Thiol acids

Thiols acidity

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