Small-angle neutron scattering studies suggest the mechanism of BinAB protein internalization

Sharma M, Aswal V, Kumar V, Chidambaram R, IUCrJ 7(2) (2020) DOI

SASDF87 – Mosqutio-larvicidal Binary (BinAB) toxin Receptor Cqm1 protein in 100% D2O

Binary toxin receptor Cqm1 protein
MWI(0) 114 kDa
MWexpected 129 kDa
log I(s) 8.20×10-2 8.20×10-3 8.20×10-4 8.20×10-5
Binary toxin receptor Cqm1 protein small angle scattering data  s, nm-1
ln I(s)
Binary toxin receptor Cqm1 protein Guinier plot ln 8.20×10-2 Rg: 2.8 nm 0 (2.8 nm)-2 s2
(sRg)2I(s)/I(0)
Binary toxin receptor Cqm1 protein Kratky plot 1.104 0 √3 sRg
p(r)
Binary toxin receptor Cqm1 protein pair distance distribution function Rg: 3.1 nm 0 Dmax: 9.7 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Binary toxin receptor Cqm1 protein PDB (PROTEIN DATA BANK) model
log I(s)
 s, nm-1
Binary toxin receptor Cqm1 protein DAMMIN model
SANS data from solutions of Mosqutio-larvicidal Binary (BinAB) toxin Receptor Cqm1 protein in 100% D2O in 25 mM HEPES, pH 7.5, 25 mM NaCl, in 100% D2O, pH 7.5 were collected using a 1 m long He3 position sensitive detector detector at a sample-detector distance of 2 m and at a wavelength of λ = 0.52 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 3.30 mg/ml was measured at 25°C. One 43200 second frame was collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.

Molecular weight estimated from experimental data using I(0) value from GNOM analysis. Submitted SANS data has been normalized to protein concentration of 1 mg/ml. Protein (3.33 mg/ml) was used during SANS experiments

Binary toxin receptor Cqm1 protein (Cqm1)
Mol. type   Protein
Organism   synthetic construct
Olig. state   Dimer
Mon. MW   64.7 kDa
Sequence   FASTA
 
PDB ID   6K5P