P73: Spontaneous oxidation of hydrogen sulfide to persulfide (s) allows signaling via sulfhydration

摘要: “Sulfhydration” has been proposed to be a means of hydrogen sulfide (H 2 S) signaling in which the H S reacts with sulfur cysteine residue proteins, thereby forming polysulfide and changing function latter, as described by equation RSH  + H S → RSSH. However, this requires oxidation RSH, cannot accomplished S, is its most reduced form (oxidation state −2). Hydropersulfides n ,  = 2–8, number = 0), can oxidize have suggested contaminant salts commonly used produce (NaSH, Na account for much activity originally attributed S. Here, we use green fluorescent protein, roGFP2, that contains two reactive residues (Cys147, Cys204) specific reporter redox status, being fully oxidized 30 mM tert-butyl hydroperoxide (t-BuOOH), dithiothreitol (DTT, 30 mM), determine if spontaneously hydro-persulfides normoxic (21% O ) laboratory conditions. We show all concentrations ranging from 1 μ M-300uM very little reductive effect on roGFP, but  > 300 uM slowly reoxidizes roGFP closed system given an hour react. attribute spontaneous hydropersulfides. Addition mixed persulfides (K  = 1–8) oxidizes at low (1uM-300uM), supporting our hypothesis. These results formed signal via sulfhydration. Support, NSF IOS-1051627 DGE-1313583.