Disease relevance of sulfanol

• A sulfenic acid enzyme intermediate is involved in the catalytic mechanism of peptide methionine sulfoxide reductase from Escherichia coli [1].
• The trapping of a sulfenic acid within the fully active C165S mutant of the AhpC peroxidase protein from Salmonella typhimurium was investigated [2].
• NADH peroxidase from Enterococcus faecalis is a tetrameric flavoenzyme of 201,400 Da which employs Cys 42 as a redox-active center cycling between sulfhydryl (Cys-SH) and sulfenic acid (Cys-SOH) states along the catalytic pathway [3].

High impact information on sulfanol

• All Prxs share the same basic catalytic mechanism, in which an active-site cysteine (the peroxidatic cysteine) is oxidized to a sulfenic acid by the peroxide substrate [4].
• Because ascorbate is present in high amounts in cells, the ascorbate/protein sulfenic acid pair represents an aspect of redox biochemistry that has yet to be explored in vivo [5].
• In vitro, the recombinant enzyme was activated upon treatment with H2O2 and the activated, but not the native enzyme, formed a covalent adduct with the sulfenic acid-specific reagent dimedone [6].
• Catalytic mechanism of thiol peroxidase from Escherichia coli. Sulfenic acid formation and overoxidation of essential CYS61 [7].
• In doing so, a reactive cysteine in the peroxiredoxin active site is weakly oxidized (disulfide or sulfenic acid) by the destroyed peroxides [8].

Biological context of sulfanol

• This is further supported by the absence of sequence homology between the two Msrs in particular around the cysteine that is involved in formation of the sulfenic acid derivative [9].
• Instead, multiple cysteines distributed in both the N-terminal substrate-binding domain (Cys147 in particular) and the C-terminal catalytic domain (Cys218) are capable of rapidly and efficiently trapping the sulfenic acid as a disulfide [10].
• The reaction is supposed to occur as a result of intramolecular acyl transfer from Cys-149 to a sulfenic acid form of Cys-153, followed by hydrolysis of the intermediate [11].
• In this paper, a new strategy is described, which makes use of beta-elimination/Michael addition reactions to introduce a functional group at the original site of phosphorylation, which gives rise to a dimethylamine-containing sulfenic acid derivative with a unique m/z value [12].

Associations of sulfanol with other chemical compounds

• The inhibited PTP1B could be partially reactivated by treatment with reducing agents such as hydroxylamine (NH2OH) and N,N'-dimethyl-N, N'-bis(mercaptoacetyl)hydrazine, indicating the presence of other oxidized forms such as sulfenic acid (Cys-SOH) [13].
• RESULTS: Using electrospray liquid chromatography / mass spectrometry, we have demonstrated that oxidation of tetrachlorohydroquinone dehalogenase with H2O2 results in formation of a sulfenic acid at Cys13 [14].
• Specific and reversible inactivation of protein tyrosine phosphatases by hydrogen peroxide: evidence for a sulfenic acid intermediate and implications for redox regulation [15].
• Inhibition of cathepsin K by nitric oxide donors: evidence for the formation of mixed disulfides and a sulfenic acid [16].
• Critical role of sulfenic acid formation of thiols in the inactivation of glyceraldehyde-3-phosphate dehydrogenase by nitric oxide [17].

Gene context of sulfanol

• The oxidized intermediate of PrxV is thus distinct from those of other Prx enzymes, which form either an intermolecular disulfide or a sulfenic acid intermediate [18].
• It was first characterized for its regulation of Prx(s) through reduction of the conserved cysteine from sulfinic to sulfenic acid, thereby impacting the role of Prx in regulation of downstream transcription factors and kinase signaling pathways [19].
• These findings suggest that nitric oxide inhibits GAPDH activity by modifications of the thiols which are essential for this activity, and that the modification includes formation of sulfenic acid, which is not restored by DTT [17].
• Human flavin-containing monooxygenase form 2 S-oxygenation: sulfenic acid formation from thioureas and oxidation of glutathione [20].
• This result demonstrates that the NOR-1-dependent formation of cathepsin K sulfinic and sulfonic acids occurs via a sulfenic acid [16].

References