Pro → Ala‐35 Rhodobacter capsulatus cytochrome c 2 shows dynamic not structural differences

FEBS Letters

MacKenzie, Neil E.¹  Gooley, Paul R.¹ 

[1] Dept. of Pharmaceutical Sciences, College of Pharmacy, University of Arizona, Tucson, AZ 85721, USA

关键词: Cytochrome;    Cytochrome c 2 NMR;    NMR;    nuclear magnetic resonance spectroscopy;    ID;    one-dimensional;    2D;    two-dimensional;    HMQC;    2D heteronuclear multiple quantum correlated spectroscopy;    TOCSY;    2D total correlated spectroscopy;    DQF-COSY;    2D double quantum filtered correlated spectroscopy;    NOE;    nuclear Overhauser effect;    NOESY;    2D NOE spectroscopy;   

DOI  :  10.1016/0014-5793(90)80109-V

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Comparative analysis of nuclear Overhauser effects show that the time average conformation of the wild-type and mutant Pro → Ala-35 Rhodobacter capsulatus cytochrome c ₂ are indistinguishable. The ring resonances of Phe-51 and Tyr-53 show that their ring flip rates increase in P35A. NH proton exchange studies show that the exchange rates of the NH of Gly-34 and the N_πH of His-17 increase by ≈ 10² in P35A suggesting that their respective hydrogen bonds are destabilized in this protein. However, ³ _αNH^{. 1}H and ¹⁵N chemical shift data argue that these bonds are intact. These data are compatible if the replacement of a Pro with an Ala residue forms a cavity or increases local flexibility thus reducing steric hinderance and increasing solvent accessibility.

【 授权许可】

Unknown