An alternative flexible conformation of the E. coli HU[beta]^sub 2^ protein: structural, dynamics, and functional aspects

• Published in: European biophysics journal Vol. 40; no. 2; p. 117
• Main Authors: Garnier, Norbert, Loth, Karine, Coste, Franck, Augustyniak, Rafal, Nadan, Virginie, Damblon, Christian, Castaing, Bertrand
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer Nature B.V 01-02-2011
• Subjects: Biomechanics; E coli; High temperature; Molecular structure; Proteins; Temperature
• ISSN: 0175-7571; 1432-1017
• DOI: 10.1007/s00249-010-0630-y

The histone-like HU protein is the major nucleoid-associated protein involved in the dynamics and structure of the bacterial chromosome. Under physiological conditions, the three possible dimeric forms of the E. coli HU protein (EcHU[alpha]^sub 2^, EcHU[beta]^sub 2^, and EcHU[alpha][beta]) are in thermal equilibrium between two dimeric conformations (N2 I^sub 2^) varying in their secondary structure content. High-temperature molecular dynamics simulations combined with NMR experiments provide information about structural and dynamics features at the atomic level for the N2 to I^sub 2^ thermal transition of the EcHU[beta]^sub 2^ homodimer. On the basis of these data, a realistic 3D model is proposed for the major I^sub 2^ conformation of EcHU[beta]^sub 2^. This model is in agreement with previous experimental data. [PUBLICATION ABSTRACT]