15N magnetic relaxation study of backbone dynamics of the ribosome-associated cold shock response protein Yfia of Escherichia coli.
In the solution structure of the ribosome-associated cold shock response protein Yfia of Escherichia coli in the free state two structural segments can be distinguished: a well structured, rigid N-terminal part displaying a betaalphabetabetabetaalpha topology and a flexible C-terminal tail comprising last 20 amino-acid residues. The backbone dynamics of Yfia protein was studied by (15)N nuclear magnetic relaxation at three magnetic fields and analyzed using model-free approach. The overall diffusional tumbling of the N-terminal part is strongly anisotropic with a number of short stretches showing increased mobility either on a subnanosecond time scale, or a micro- to millisecond time scale, or both. In contrast, the unstructured polypeptide chain of the C-terminal part, which cannot be regarded as a rigid structure, shows the predominance of fast local motions over slower ones, both becoming faster closer to the C-terminus.
Zhukov
Igor
I
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland.
Bayer
Peter
P
Schölermann
Beate
B
Ejchart
Andrzej
A
D004926:Escherichia coli / Q000737:chemistry; D029968:Escherichia coli Proteins / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008958:Models, Molecular; D009587:Nitrogen Isotopes / Q000737:chemistry; D011487:Protein Conformation; D012269:Ribosomal Proteins / Q000737:chemistry*
D029968:Escherichia coli Proteins; D009587:Nitrogen Isotopes; C434525:RaiA protein, E coli; D012269:Ribosomal Proteins