Premium
An alternate conformation of the hyperthermostable HU protein from Thermotoga maritima has unexpectedly high flexibility
Author(s) -
Durney Michael A,
Wechselberger Rainer W,
Kalodimos Charalampos G,
Kaptein Robert,
Vorgias Constantinos E,
Boelens Rolf
Publication year - 2004
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/s0014-5793(04)00247-9
Subject(s) - thermotoga maritima , flexibility (engineering) , chemistry , biology , biochemistry , mathematics , statistics , gene , escherichia coli
The homodimeric HU protein from the hyperthermophile Thermotoga maritima (HU Tmar ) is a model system which can yield insights into the molecular determinants of thermostability in proteins. Unusually for a thermostable protein, HU Tmar 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 HU Tmar in which the major form closely resembles the X‐ray structure while the very flexible minor form is less structured. HU Tmar may therefore be a new example of the small class of hyperthermostable proteins with unexpected flexibility.