Sulphydryl compound

Haddock, P.S., Woodward, B., Hearse, D.J. and Dodds, R. (1991). Modification of the activity of bovine Na/K ATPase by reduced and oxidised glutathione and other sulphydryl compounds. Br. J. Pharmacol. 102, 54P. 

Dabrowski, A. and Chwiecko, M. (1990). Oxygen radicals mediate depletion of pancreatic sulphydryl compounds in rats with caerulein-induced acute pancreatitis. Digestion 7, 15-19. 

Loguercio, C., Romano, M., Taranto, D., Nardi, G., Di Sapio, M. and Del Vecchio Blanco, C. (1990). Regional variations in tissue levels of sulphydryl compounds in the human gastric mucosa effect of ethanol. Gastroenterology 98, A81. 

Biotinidase activity in blood and plasma samples can decrease, often in an unpredictable manner, during storage at room temperature or at +4°C, but also during prolonged storage at -20°C, whereas no decrease has been observed at -70°C [5, 15, 32, 35]. However, storage at -70°C is not possible in many centres or practises that send samples for biotinidase assay. Addition of a sulphydryl compound to the assay mixture has been shown to restore activity in blood samples stored at room temperature [35]. Using our assay, which includes 0.5 mM DTT in the assay mix-... 

Arora et al., 1995 Engels et al., 1997). Thioesters are formed by the reaction of an FFA with a sulphydryl compound, particularly methanethiol (CH3SH Molimard and Spinnler, 1996 Collins et al., 2003a, 2004). Methylthioesters of short-chain FFAs have been associated with the characteristic aromas of Cheddar and smear-ripened cheeses (Arora et al., 1995 Lamberet et al., 1997). 

RSH groups are not easy to assay. Some arise during the handling of the biological material before the measurements are made and some arise from the lack of specificity of many reagents used as probes for quantitation of sulphydryl compounds (reviewed in Russo and Bump, 1989). 

Sulphydryl compounds belong to the most important among biologically active substances. The polarographic behaviour of sulphydryl compounds... 

Although its theory is not quite clear, the Brdidka catalytic effect of cysteine or proteins is so typical and sensitive, that it is suitable for use in the analysis. It is not possible to discuss here the whole theory of catalytic currents of sulphydryl compounds (see also [133-141]) but some characteristics must be mentioned. 

The polarographic examination of sulphosalicylic filtrate has been applied by Brdicka and later on by many others to the determination of some degradation products or fractions of the serum proteins in blood of ill humans [3,127,130,147-153]. The increase of Brdicka protein wave in sulphosalicylic filtrate is characteristic of sera of patients suffering from cancer or some inflammatory disease. The Brdicka test is simple, quick and reproducible. Sulphydryl compounds which cause the increase of the... 

The reactive nitrenium or carbonium ions postulated to be produced will react with nucleophilic groups in nucleic acids, proteins and sulphydryl compounds such as glutathione and methionine. The arylation of DNA by acetylaminofluorene has been demonstrated in vivo and in vitro. The involvement of sulphate conjugation brings other factors into play. Depletion of body sulphate reduces and supplementation with organic sulphate increases the carcinogenicity of acetylaminofluorene. The production of covalent adducts between acetylaminofluorene and cellular macromolecules in vivo can be shown to be correspondingly decreased and increased by manipulation of body sulphate levels. 

Upon entry into bacterial cells, the disulphide bond in compound (3) is reduced by sulphydryl compounds present in the intracellular milieu, resulting in the formation of the... 

Shenoy NR, Choughuley AS. Inhibitory effect of diet related sulphydryl compounds on the formation of carcinogenic nitrosamines. Cancer Lett 1992 65 227-232. 

Aldridge WN (1951) The conversion of cyanogen chloride to cyanide in the presence of blood proteins and sulphydryl compounds. Biochem J 48 271-276. 

Mild oxidation of sulphydryl compounds converts them into disulphides. 

In a biological system the reductive-cleavage of disulphide (cystine) bonds in proteins and peptides may be a very important reaction of alkylphosphines. PBU3 and the water-soluble phosphines P(CH20H)3 and P(CH2COOH)3 have been used as alternatives to sulphydryl compounds (e.g. 2-mercaptoethanol) to cleave disulphide (cystine) bonds selectively in several proteins, under mild conditions (see Table 13). 

Sodium Nitroprusside (Nitroferrocyanide), 5 per cent. Reagent for sulphydryl compounds, including cysteine, thioneine, and glutathione. Also reacts with acetone, acetoacetic acid, creatinine and indole. 

Quantitative determination of ascorbic acid in biological fluids and processed foods is hindered by interference by ferrous, cuprous and stannous ions, phenols, sulphydryl compounds, reductone (LXXIX), reductic acid (LXXVIII) and tartronaldehyde (LXXX). The most commonly used method of estimation is based on the rapid reduction of 2,6-dichlorophenol-indo-phenol ( indophenol ) to its leuco form by ascorbic acid. This method, which Wcisfirst introduced by Tillmanns, Hirsch and Hirsch , involves the titration of an acid extract of the tissue or vitamin with a dilute solution of the dye. 

The enzyme porphobilinogen synthetase is widespread in animal and plant tissues [73, 74] and is activated by sulphydryl compounds. It condenses two molecules of ALA to form the monopyrrole porphobilinogen (PBG) [75]. 

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