title: Selective separation of tryptophan-containing peptides via hydrophobic modification with 2-nitro-4-carboxyphenylsulfenyl chloride.
abstract: Selective separation of tryptophan-containing peptides has been attempted using 2-nitro-4-carboxyphenylsulfenyl chloride (NCps)-C1 as a reagent for hydrophobic modification of tryptophan. S-Carboxymethylated proteins were modified with NCps-C1 in 70% acetic acid and digested with TPCK-trypsin, and the digests were fractionated, directly or after partial fractionation on a Sephadex G-25 column, by high performance liquid chromatography using a reverse phase column. The tryptophan-containing peptides from the tryptic digests of S-carboxymethylated hen-egg white lysozyme and Trimeresurus flavoviridis phospholipase A2 were thus selectively separated and the amino acid sequences were determined, showing the validity of the method. The phenylthiohydantoin derivative of 2-(2'-nitro-4'-carboxyphenylthio)-L-tryptophan was synthesized and its spectroscopic and chromatographic properties determined, enabling us to identify the derivative on Edman sequencing.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002645:Chickens; D002846:Chromatography, Affinity / Q000379:methods*; D009113:Muramidase / Q000032:analysis*; D009579:Nitrobenzoates; D010446:Peptide Fragments / Q000302:isolation & purification*; D010740:Phospholipases / Q000032:analysis*; D010741:Phospholipases A / Q000032:analysis*; D054467:Phospholipases A2; D012995:Solubility; D014364:Tryptophan
chemical_list: D000596:Amino Acids; D009579:Nitrobenzoates; D010446:Peptide Fragments; C046448:2-nitro-4-carboxyphenylsulfenyl chloride; D014364:Tryptophan; D010740:Phospholipases; D010741:Phospholipases A; D054467:Phospholipases A2; D009113:Muramidase