Identification of a cross-linked peptide of a covalent complex between adrenodoxin reductase and adrenodoxin.

摘要: A cross-linked complex between bovine NADPH-adrenodoxin reductase (AR) and adrenodoxin (AD) was prepared with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide purified, as described previously [Hara, T. & Kimura, (1989) J. Biochem. 105, 594-600]. The covalent S-pyridylethylated digested lysylendopeptidase, the resulting peptides were separated by reversed-phase HPLC to identify peptide. Comparison of chromatograms showed that (i) two tandem (K-4 K-5) from AD a peptide (K-1) AR missing in chromatogram (ii) single new peak observed complex. Amino acid composition sequence analyses newly covalently formed K-4-K-5 (Ile-25-Lys-98) derived K-1 (Ser-1-Lys-27) AR, which an amide bond had been epsilon-amino group Lys-66 gamma-carboxyl Glu-4 AR. These results indicate binding site is localized amino-terminal part around AD. six clustered basic amino residues (His-24, Lys-27, His-28, His-29, Arg-31, His-33) present portion eight acidic (Glu-65, Glu-68, Asp-72, Glu-73, Glu-74, Asp-76, Asp-79, Asp-86) middle may play important role formation.