An alternate conformation of the hyperthermostable HU protein from Thermotoga maritima has unexpectedly high flexibility

FEBS Letters

Boelens, Rolf²  Kaptein, Robert²  Wechselberger, Rainer W²  Durney, Michael A²  Kalodimos, Charalampos G²  Vorgias, Constantinos E¹ 

[1] Department of Biochemistry and Molecular Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece;Bijvoet Center for Biomolecular Research, Universiteit Utrecht, Padualaan 8, 3584 CH Utrecht, The Netherlands

关键词: Conformational flexibility;    Protein dynamics;    Thermostability;    Nuclear magnetic resonance spin relaxation;    HUTmar;    Thermotoga maritima HU protein;    HUBst;    Bacillus stearothermophilus HU protein;    HUBsu;    Bacillus subtilis HU protein;    IHF;    integration host factor;    NOE;    nuclear Overhauser enhancement;    R 1;    R 2;    longitudinal and transverse relaxation rates;    HSQC;    heteronuclear single quantum coherence;    NOESY;    nuclear Overhauser enhancement spectroscopy;   

DOI  :  10.1016/S0014-5793(04)00247-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The homodimeric HU protein from the hyperthermophile Thermotoga maritima (HUTmar) is a model system which can yield insights into the molecular determinants of thermostability in proteins. Unusually for a thermostable protein, HUTmar exists in a structurally heterogeneous state as evidenced by the assignment of two distinct and approximately equally populated forms in solution. Relaxation measurements combined with chemical shift, hydrogen exchange, and nuclear Overhauser enhancement data confirm the main structural features of both forms. In addition, these data support a two-state model for HUTmar in which the major form closely resembles the X-ray structure while the very flexible minor form is less structured. HUTmar may therefore be a new example of the small class of hyperthermostable proteins with unexpected flexibility.

【 授权许可】

Unknown