thioether crosslinked residues 2'-(S-L-cysteinyl)-6'-hydroxy-L-tryptophan sulfoxide 29.974178314208984375 29.979999542236328125 319.06268310546875 319.339996337890625 MOD:01380 6'-hydroxy-S-oxo-tryptathionine 2-((2R)-2-amino-2carboxyethyl)sulfinyl-3-((2S)-2-amino-2-carboxyethyl)-1H-indole Cross-link 2. CROSSLNK 2'-cysteinyl-6'-hydroxytryptophan sulfoxide (Trp-Cys) PSI-MOD none C 14 H 13 N 3 O 4 S 1 H -2 O 2 C, W A protein modification that effectively cross-links an L-cysteine residue and an L-tryptophan residue by a thioether bond to form 2'-(S-L-cysteinyl)-6'-hydroxy-L-tryptophan sulfoxide. natural 2'-(S-L-cysteinyl)-6'-hydroxy-L-tryptophan sulfoxide crosslinked L-tryptophan residue