Structural insights into the dynamics and function of the C-terminus of the E. coli RNA chaperone Hfq.

Beich-Frandsen M, Vecerek B, Konarev PV, Sjöblom B, Kloiber K, Hämmerle H, Rajkowitsch L, Miles AJ, Kontaxis G, Wallace BA, Svergun DI, Konrat R, Bläsi U, Djinovic-Carugo K, Nucleic Acids Res 39(11):4900-15 (2011) Europe PMC

SASDAG5 – RNA shaperone Hfq

RNA chaperone Hfq
MWexperimental 67 kDa
MWexpected 67 kDa
VPorod 110 nm3
log I(s) 1.30×102 1.30×101 1.30×100 1.30×10-1
RNA chaperone Hfq small angle scattering data  s, nm-1
ln I(s)
RNA chaperone Hfq Guinier plot ln 1.30×102 Rg: 3.2 nm 0 (3.2 nm)-2 s2
(sRg)2I(s)/I(0)
RNA chaperone Hfq Kratky plot 1.104 0 √3 sRg
p(r)
RNA chaperone Hfq pair distance distribution function Rg: 3.2 nm 0 Dmax: 11.2 nm

Data validation

Fits and models

log I(s)
 s, nm-1
RNA chaperone Hfq DAMMIN model
log I(s)
 s, nm-1
RNA chaperone Hfq BUNCH model
Synchrotron SAXS data from solutions of RNA shaperone Hfq in 50 mM Tris-HCL 150 mM NaCl 1.0 mM DTT, pH 7.5 were collected on the EMBL X33 beam line at the DORIS III storage ring (Hamburg, Germany) using a MAR 345 Image Plate detector (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). Solute concentrations ranging between 2.3 and 18.5 mg/ml were measured at 37°C. Two successive 120 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted. The low angle data collected at lower concentration were merged with the highest concentration high angle data to yield the final composite scattering curve.

RNA chaperone Hfq (Hfq)
Mol. type   Protein
Organism   Escherichia coli
Olig. state   Hexamer
Mon. MW   11.2 kDa
Sequence   FASTA