Small-angle neutron scattering solution structures of NADPH-dependent sulfite reductase

Murray D, Weiss K, Stanley C, Nagy G, Stroupe M, Journal of Structural Biology 213(2):107724 (2021) DOI

SASDKH6 – Sulfite reductase flavoprotein-43/hemoprotein heterodimer

Sulfite reductase [NADPH] hemoprotein beta-component (Assimilatory NADPH-dependent sulfite reductase hemoprotein)
Sulfite reductase [NADPH] flavoprotein alpha-component (Assimilatory NADPH-dependent sulfite reductase flavoprotein)

MW^experimental	111	kDa
MW^expected	106	kDa

log I(s) 6.41×10^-1 6.41×10^-2 6.41×10^-3 6.41×10^-4

Sulfite reductase [NADPH] hemoprotein beta-component (Assimilatory NADPH-dependent sulfite reductase hemoprotein) Sulfite reductase [NADPH] flavoprotein alpha-component (Assimilatory NADPH-dependent sulfite reductase flavoprotein) small angle scattering data

s, nm^-1

Log plot Log-Log plot

ln I(s)

ln 6.41×10^-1 R_g: 3.2 nm 0 (3.2 nm)^-2 s²

(sR_g)²I(s)/I(0)

1.104 0 √3 sR_g

p(r)	R_g: 3.4 nm 0 D_max: 9.9 nm

Data validation

Experimental data range

p(r) fit to data

Metric

Value

s_min D_max / π

0.4

N_Shannon

Worse

Better

Metric

Value

p_cormap

χ²

0.323
1.805

Worse

Better

Fits and models

log I(s)	s, nm^-1
+3 Δ/σ -3	s, nm^-1

SANS data from solutions of Sulfite reductase flavoprotein-43/hemoprotein heterodimer in 50 mM KPi, 100 mM NaCl, 1 mM EDTA, pH 7.8 were collected using the EQ-SANS (BL-6) beam line (Spallation Neutron Source, Oak Ridge National Laboratory, USA) equipped with a GE linear position-sensitive detector at a sample-detector distance of 4 m and at a wavelength of λ = 0.25 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 5.00 mg/ml was measured at 8°C. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.

X-ray Exposure time = UNKNOWN. Number of frames = UNKNOWN

Sulfite reductase [NADPH] hemoprotein beta-component (Assimilatory NADPH-dependent sulfite reductase hemoprotein) (SiRHP)
Mol. type		Protein
Organism		Escherichia coli (strain K12)
Olig. state		Monomer
Mon. MW		64.0 kDa

UniProt		P17846 (1-570)
Sequence		FASTA

Sulfite reductase [NADPH] flavoprotein alpha-component (Assimilatory NADPH-dependent sulfite reductase flavoprotein) (SiRFP-43)
Mol. type		Protein
Organism		Escherichia coli (strain K12)
Olig. state		Monomer
Mon. MW		42.3 kDa

UniProt		P38038 (226-374)
Sequence		FASTA