The major diagnostic VSG LiTat 1.3 of the human parasite Trypanosoma brucei gambiense is a trimer in solution

Danel N, Geens R, Mares-Mejía I, Versées W, Van Den Abbeele J, Sterckx Y Soldati-Favre D, PLOS Pathogens 22(8):e1014530 (2026) DOI

SASDXA9 – Trypanosoma brucei gambiense, Variant Surface Glycoprotein (VSG) LiTat 1.3

Variant surface glycoprotein LiTat 1.3
MWexperimental 142 kDa
MWexpected 145 kDa
VPorod 252 nm3
log I(s) 4.32×10-1 4.32×10-2 4.32×10-3 4.32×10-4
Variant surface glycoprotein LiTat 1.3 small angle scattering data  s, nm-1
ln I(s)
Variant surface glycoprotein LiTat 1.3 Guinier plot ln 4.32×10-1 Rg: 4.8 nm 0 (4.8 nm)-2 s2
(sRg)2I(s)/I(0)
Variant surface glycoprotein LiTat 1.3 Kratky plot 1.104 0 √3 sRg
p(r)
Variant surface glycoprotein LiTat 1.3 pair distance distribution function Rg: 5.0 nm 0 Dmax: 16.5 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Variant surface glycoprotein LiTat 1.3 BILBOMD model
Synchrotron SAXS data from solutions of Trypanosoma brucei gambiense, Variant Surface Glycoprotein (VSG) LiTat 1.3 in 20 mM HEPES, 150 mM NaCl, 3% glycerol, pH 7.4 were collected on the SWING beam line at the SOLEIL storage ring (Saint-Aubin, France) using a Eiger 4M detector at a sample-detector distance of 2 m and at a wavelength of λ = 0.1 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). In-line size-exclusion chromatography (SEC) SAS was employed. The SEC parameters were as follows: A 80.00 μl sample at 15.5 mg/ml was injected at a 0.20 ml/min flow rate onto a Shodex KW404-4F column at 20°C. 1000 successive 0.750 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.

Variant surface glycoprotein LiTat 1.3 (TbgVSG LiTat1.3)
Mol. type   Protein
Organism   Trypanosoma brucei gambiense
Olig. state   Trimer
Mon. MW   48.2 kDa
 
UniProt   X5GEX5
Sequence   FASTA