NMR study of the interaction between cytochrome b5 and cytochrome c. Observation of a ternary complex formed by the two proteins and [Cr(en)3]3+.
The interaction between horse cytochrome c and the tryptic fragment of bovine liver microsomal cytochrome b5 in the absence and presence of [Cr(ethylenediamine)3]Cl3 was studied by 1H NMR spectroscopy. The protein-protein interaction region on cytochrome b5 was found to be different from the [Cr(en)3]3+-binding region. The solvent-exposed propionate-bearing edge of the haem of cytochrome b5 is accessible to [Cr(en)3]3+ in the interprotein complex.
D000818:Animals; D001665:Binding Sites; D001667:Binding, Competitive; D002417:Cattle; D002857:Chromium / Q000378:metabolism*; D003573:Cytochrome b Group / Q000378:metabolism*; D003574:Cytochrome c Group / Q000378:metabolism*; D015786:Cytochromes b5; D005029:Ethylenediamines / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008862:Microsomes, Liver / Q000032:analysis; D009942:Organometallic Compounds / Q000378:metabolism*
D003573:Cytochrome b Group; D003574:Cytochrome c Group; D005029:Ethylenediamines; D009942:Organometallic Compounds; D002857:Chromium; C051941:chromium triethylenediamine; D015786:Cytochromes b5