Analysis of self-assembly of S-layer protein slp-B53 from Lysinibacillus sphaericus.

Liu J, Falke S, Drobot B, Oberthuer D, Kikhney A, Guenther T, Fahmy K, Svergun D, Betzel C, Raff J, Eur Biophys J 46(1):77-89 (2017) Europe PMC

SASDA49 – Cation-free slp-B53

S-layer protein
MWexperimental 166 kDa
MWexpected 116 kDa
VPorod 495 nm3
log I(s) 1.37×104 1.37×103 1.37×102 1.37×101
S-layer protein small angle scattering data  s, nm-1
ln I(s)
S-layer protein Guinier plot ln 1.38×104 Rg: 5.8 nm 0 (5.8 nm)-2 s2
S-layer protein Kratky plot 1.104 0 3 sRg
S-layer protein pair distance distribution function Rg: 6.1 nm 0 Dmax: 22 nm

Data validation

Fits and models

log I(s)
 s, nm-1
S-layer protein DAMMIF model

log I(s)
 s, nm-1
S-layer protein SASREF MX model
S-layer protein SASREF MX model

Synchrotron SAXS data from solutions of Cation-free slp-B53 in Water, pH 7 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). Solute concentrations ranging between 1 and 7.5 mg/ml were 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. The low angle data collected at lower concentrations were extrapolated to infinite dilution and merged with the higher concentration data to yield the final composite scattering curve.

S-layer protein (Slp1)
Mol. type   Protein
Organism   Lysinibacillus sphaericus
Olig. state   Monomer
Mon. MW   116.0 kDa
UniProt   M4N8T6
Sequence   FASTA