has functional parent S-12-hydroxyfarnesyl-L-cysteine L-cysteine methyl ester modified L-cysteine residue S-12-hydroxyfarnesyl-L-cysteine methyl ester 234.1983642578125 234.3800048828125 354.210296630859375 354.529998779296875 C natural PSI-MOD S12HyFarnOMeCys C 19 H 32 N 1 O 3 S 1 MOD:01133 C 16 H 26 O 1 C-term A protein modification that effectively converts an L-cysteine residue to S-12-hydroxyfarnesyl-L-cysteine methyl ester.