title: Peptide purification by affinity chromatography based on alpha-ketoacyl group chemistry.
abstract: Significant advances have been achieved in the fields of peptide/protein synthesis, permitting the preparation of large, complex molecules. Shortcomings, however, continue to exist in the area of peptide purification. This paper details some studies we undertook to develop a new strategy for peptide purification based on a reactivity of alpha-ketoacyl groups in peptides. The alpha-ketoacyl peptide was generated from N(epsilon)-acyl-lysyl-peptide in the solid phase via a transamination reaction using glyoxylic acid and nickel(II) ion. Cleavage of the alpha-ketoacyl group with o-phenylenediamine gave the target peptide in an acceptable yield and purity. We first carried out a careful step-by-step optimization of the purification conditions using a model peptide. The strategy was then used in the purification of a transmembrane peptide that could not be effectively purified using a conventional RP-HPLC system due to the strong hydrophobicity of the peptide and its high tendency to aggregate.
authors.affiliation: Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Hara
authors.forename: Akira
authors.initials: A
authors.lastname: Tainosho
authors.forename: Ken'ichiroh
authors.initials: K
authors.lastname: Nakamura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Sato
authors.forename: Toru
authors.initials: T
authors.lastname: Kawakami
authors.forename: Saburo
authors.initials: S
authors.lastname: Aimoto
mesh_terms: D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D015394:Molecular Structure; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D010455:Peptides