Cooperative folding of intrinsically disordered domains drives assembly of a strong elongated protein.

Gruszka DT, Whelan F, Farrance OE, Fung HK, Paci E, Jeffries CM, Svergun DI, Baldock C, Baumann CG, Brockwell DJ, Potts JR, Clarke J, Nat Commun 6:7271 (2015) Europe PMC

SASDA67 – Surface Protein G (SasG) EG5 repeat protein G51-G55

Surface protein G
MWI(0) 48 kDa
MWexpected 67 kDa
VPorod 87 nm3
log I(s) 9.92×103 9.92×102 9.92×101 9.92×100
Surface protein G small angle scattering data  s, nm-1
ln I(s)
Surface protein G Guinier plot ln 9.92×103 Rg: 12 nm 0 (12 nm)-2 s2
Surface protein G Kratky plot 1.104 0 3 sRg
Surface protein G pair distance distribution function Rg: 13.4 nm 0 Dmax: 48 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Surface protein G SASREF model

log I(s)
 s, nm-1
Surface protein G GASBOR model

Synchrotron SAXS data from solutions of Surface Protein G (SasG) EG5 repeat protein G51-G55 in 20 mM Tris 200 mM NaCl 1 mM EDTA 20 mM Tris.Cl, pH 7.5 were collected on the EMBL P12 beam line at the PETRA III storage ring (Hamburg, Germany) using a Pilatus 2M detector at a sample-detector distance of 3.1 m and at a wavelength of λ = 0.12 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 7.00 mg/ml was measured at 10°C. 20 successive 0.050 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.

SAXS was used to determine whether the EG5 repeat forms an extended rod-like structure in solution.

Surface protein G (SasG)
Mol. type   Protein
Organism   Staphylococcus aureus
Olig. state   Monomer
Mon. MW   66.9 kDa
UniProt   Q2G2B2 (419-1013)
Sequence   FASTA