A conformational fingerprint for amyloidogenic light chains

Paissoni C, Puri S, Broggini L, Sriramoju M, Maritan M, Russo R, Speranzini V, Ballabio F Nuvolone M, Merlini G, Palladini G, Hsu S, Ricagno S, Camilloni C, eLife 13 (2025) DOI

SASDVK4 – Immunoglobulin light chain AL55

Immunoglobulin light chain AL55

MW^experimental	47	kDa
MW^expected	47	kDa
V^Porod	61	nm³

log I(s) 9.21×10¹ 9.21×10⁰ 9.21×10^-1 9.21×10^-2

Immunoglobulin light chain AL55 small angle scattering data

s, nm^-1

Log plot Log-Log plot

ln I(s)

Immunoglobulin light chain AL55 Guinier plot

ln 9.21×10¹ R_g: 2.6 nm 0 (2.6 nm)^-2 s²

(sR_g)²I(s)/I(0)

Immunoglobulin light chain AL55 Kratky plot

1.104 0 √3 sR_g

p(r)	R_g: 2.6 nm 0 D_max: 8.5 nm

Data validation

Experimental data range

p(r) fit to data

Metric

Value

s_min D_max / π

0.3

N_Shannon

Worse

Better

Metric

Value

p_cormap

χ²

0.130
1.139

Worse

Better

Fits and models

log I(s)	s, nm^-1
+3 Δ/σ -3	s, nm^-1

Immunoglobulin light chain AL55 SWISSMODEL model

Synchrotron SAXS data from solutions of immunoglobulin light chain AL55 in 20 mM TrisHCL, 150 mM NaCl, pH 8 were collected on the BM29 beam line at the ESRF (Grenoble, France) using a Pilatus3 2M detector at a sample-detector distance of 2.8 m and at a wavelength of λ = 0.099 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 2.60 mg/ml was 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.

Immunoglobulin light chain AL55 (AL55)
Mol. type		Protein
Organism		Homo sapiens
Olig. state		Dimer
Mon. MW		23.3 kDa
Sequence		FASTA