β2-Type Amyloid-Like Fibrils of Poly-L-Glutamic Acid Convert into Long Highly Ordered Helices upon Dissolution in Dimethyl Sulfoxide

Berbeć S, Dec R, Molodenskiy D, Wielgus-Kutrowska B, Johannessen C, Hernik-Magoń A, Tobias F, Bzowska A, Ścibisz G, Keiderling T, Svergun D, Dzwolak W, The Journal of Physical Chemistry B (2018) DOI

SASDED8 – Poly-L-Glutamic Acid in Dimethyl Sulfoxide (DMSO)

Poly-L-Glutamic Acid
MWexperimental 7 kDa
MWexpected 6 kDa
VPorod 5 nm3
log I(s) 6.90×102 6.90×101 6.90×100 6.90×10-1
Poly-L-Glutamic Acid small angle scattering data  s, nm-1
ln I(s)
Poly-L-Glutamic Acid Guinier plot ln 6.90×102 Rg: 1.8 nm 0 (1.8 nm)-2 s2
(sRg)2I(s)/I(0)
Poly-L-Glutamic Acid Kratky plot 1.104 0 3 sRg
p(r)
Poly-L-Glutamic Acid pair distance distribution function Rg: 2.0 nm 0 Dmax: 7.8 nm

Data validation


Fits and models


log I(s)
 s, nm-1
Poly-L-Glutamic Acid PYMOL model

Synchrotron SAXS data from Poly-L-Glutamic Acid (PGLA) in neat dimethyl sulfoxide were collected on the EMBL-P12 beam line at the PETRA III storage ring (Hamburg, Germany) using a Pilatus 2M detector at a wavelength of λ = 0.124 nm (l(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). Solute concentrations ranging between 10 and 30 mg/ml were measured at 20°C. 40 successive 0.045 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 concentration were merged with the highest concentration high angle data to yield the final composite scattering curve.

Poly-L-Glutamic Acid (PLGA)
Mol. type   Other
Olig. state   Other
Mon. MW   0.1 kDa
Sequence   FASTA