Hydrogen sulfide gas and perthiol chemical groups (RSSH) are regulators of metabolism and may serve to protect enzymes against reactive oxygen species. The source of biological perthiols is not fully understood. The human protein CCBL1 is known to cleave C-S bonds in certain substrates such as cysteine. We hypothesize that CCBL1 will react with cystine and cystamine to produce products containing a perthiol. We will measure the kinetics of the enzymatic reaction using visible spectroscopy. Additional reactions involving the perthiol may occur in our reaction vessel, thus possible additional products will be detected using Raman and NMR spectroscopy.
We anticipate that this enzymatic reaction will occur at a biologically-relevant rate, which would suggest that this reaction is a biological source of perthiols.