An analysis of pseudocontact shifts and their relationship to structural features of the redox states of cytochrome b 5

FEBS Letters

Veitch, Nigel C.²  Whitfbrd, David¹  Williams, Robert J.P.² 

[1] Department of Biochemistry, University of Oxford, South Parks Road, Oxford, 0X1 3QR, UK;Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, 0X1 3QR, UK

关键词: Cytochrome b 5;    Pseudocontact shift;    Protein conformation;    Nuclear magnetic resonance;    Cytochrome c;   

DOI  :  10.1016/0014-5793(90)81180-V

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The assignment of proton resonances inboth redox states of a heme protein is necessary for the evaluation of pseudocontact shift data. Many new assignments are presented here for cytochrome b ₅ particularly in the paramagnetic oxidised state, thereby allowing both the calculation of electronic g-tensor values with the magnetic axis orientation and a comparison of observed and calculated pseudocontact shifts utilising a computational procedure. The possible redox linked confonnational changes are found to be minimal in contrast with cytochrome c although the procedure additionally highlights aspects of the mobility of certain residues in cytochrome b ₅. In this respect the residue Gly-42 appears mobile both by this method and by the observation from NMR spectra of a major and minor conformation in this region.

【 授权许可】

Unknown