Table I Number of identified TCEP-induced reaction products

TCEP-induced reaction products in a tryptic digest of an E. coli proteome pulse-labeled with azhal were isolated by COFRADIC and identified by LC-tandem MS as described under “Experimental Procedures.” HS, homoserine.

TCEP-induced reaction productNumber of peptides
DAB-containing peptides641
HS-containing peptides644
HS- and DAB-containing peptides73
N-terminal fragment of cleavage at azhal22
C-terminal fragment of cleavage at azhal198
DAB- or HS-containing peptides combined with cleavage at azhala85
  • a DAB- or HS-containing peptides and N- or C-terminal cleavage products derived from the same multiple azhal residue-containing precursor peptide.