Argonaute protein SAXS investigation

lirong zheng.

SASDPU2 – apo-Thermus thermophilus argonaute protein at 75 °C

Piwi domain-containing protein
MWexperimental 72 kDa
MWexpected 77 kDa
VPorod 175 nm3
log I(s) 1.18×10-1 1.18×10-2 1.18×10-3 1.18×10-4
Piwi domain-containing protein small angle scattering data  s, nm-1
ln I(s)
Piwi domain-containing protein Guinier plot ln 1.19×10-1 Rg: 3.3 nm 0 (3.3 nm)-2 s2
(sRg)2I(s)/I(0)
Piwi domain-containing protein Kratky plot 1.104 0 √3 sRg
p(r)
Piwi domain-containing protein pair distance distribution function Rg: 3.4 nm 0 Dmax: 9.7 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Piwi domain-containing protein MOLECULAR DYNAMICS FRAME model
log I(s)
 s, nm-1
Piwi domain-containing protein GASBOR model
Synchrotron SAXS data from solutions of apo-Thermus thermophilus argonaute protein in 20 mM Tris–HCl, 250 mM NaCl, 2mM DTT, pH 8 were collected on the BL19U2 beam line at the Shanghai Synchrotron Radiation Facility (SSRF, Shanghai, China) using a Pilatus 1M detector at a sample-detector distance of 3 m and at a wavelength of λ = 0.103 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 0.30 mg/ml was measured at 75°C. 20 successive 0.500 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.

Substitute errors have been used for the ab initio GASBOR modelling (+/-1.0 on each data point).

Piwi domain-containing protein (TtAgo)
Mol. type   Protein
Organism   Thermus thermophilus (strain ATCC BAA-163 / DSM 7039 / HB27)
Olig. state   Monomer
Mon. MW   76.6 kDa
 
UniProt   Q746M7 (1-685)
Sequence   FASTA