Liposome-Based Study Provides Insight into Cellular Internalization Mechanism of Mosquito-Larvicidal BinAB Toxin.

Sharma M, Kumar A, Kumar V, J Membr Biol (2020) Europe PMC

SASDHR8 – Mosquito-larvicidal binary toxin receptor (Cqm1) protein

Synthetic construct (mutant, His-tagged): Mosquito-larvicidal BinAB toxin receptor protein (Neutral and basic amino acid transport protein rBAT)
MWexperimental 129 kDa
MWexpected 129 kDa
VPorod 97 nm3
log I(s) 5.67×101 5.67×100 5.67×10-1 5.67×10-2
Synthetic construct (mutant, His-tagged): Mosquito-larvicidal BinAB toxin receptor protein (Neutral and basic amino acid transport protein rBAT) small angle scattering data  s, nm-1
ln I(s)
Synthetic construct (mutant, His-tagged): Mosquito-larvicidal BinAB toxin receptor protein (Neutral and basic amino acid transport protein rBAT) Guinier plot ln 5.68×101 Rg: 4 nm 0 (4 nm)-2 s2
(sRg)2I(s)/I(0)
Synthetic construct (mutant, His-tagged): Mosquito-larvicidal BinAB toxin receptor protein (Neutral and basic amino acid transport protein rBAT) Kratky plot 1.104 0 3 sRg
p(r)
Synthetic construct (mutant, His-tagged): Mosquito-larvicidal BinAB toxin receptor protein (Neutral and basic amino acid transport protein rBAT) pair distance distribution function Rg: 3.2 nm 0 Dmax: 9.2 nm

Data validation


Fits and models


log I(s)
 s, nm-1
Synthetic construct (mutant, His-tagged): Mosquito-larvicidal BinAB toxin receptor protein (Neutral and basic amino acid transport protein rBAT) PDB model
Synthetic construct (mutant, His-tagged): Mosquito-larvicidal BinAB toxin receptor protein (Neutral and basic amino acid transport protein rBAT) DAMMIF model

Synchrotron SAXS data from solutions of Cqm1 protein in PBS buffer (10 mM Na2HPO4, 1.8 mM KH2PO4, 137 mM NaCl, 2.7 mM KCl), pH 7.4 were collected on the BL-18 beam line at INDUS-2 (Indore, India) using a MAR 345 Image Plate detector at a sample-detector distance of 32.4 m and at a wavelength of λ = 0.1033 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 4.60 mg/ml was measured at 25°C. One 600 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.

Low q (< 0.02 A-1) and high q > 0.25 A-1) experimental SAXS points were removed prior to ATSAS analysis. The protein exists as a dimer in solution (PDB ID, 6K5P_AB). SAXS data is on relative scale, thus concentration normalization and I(0) for MW estimation has not been done. CAUTION! Error propagation likely incorrect! CAUTION! Errors are severely over estimated. CAUTION! Buffer mismatch likely. CAUTION! Porod volume is inconsistent with a protein MW of 129 kDa. CAUTION! p(r) profile does not fit the SAXS data. CAUTION! Error on Rg (from Guinier) is in excess of 1 nm. CAUTION! sRg range is limited to 0.83 < sRg < 1.21. CAUTION! DAM model representation is derived from individual model spatial alignment and filtering (DAMFILT.pdb); individual DAM model fits not provided; NSD unknown.

Synthetic construct (mutant, His-tagged): Mosquito-larvicidal BinAB toxin receptor protein (Neutral and basic amino acid transport protein rBAT) (Cqm1)
Mol. type   Protein
Organism   Culex quinquefasciatus
Olig. state   Dimer
Mon. MW   64.7 kDa
 
UniProt   B0X223 (23-560)
Sequence   FASTA
 
PDB code   6K5P