Domain crossover in the reductase subunit of NADPH-dependent assimilatory sulfite reductase.

Walia N, Murray DT, Garg Y, He H, Weiss KL, Nagy G, Elizabeth Stroupe M, J Struct Biol 215(4):108028 (2023) Europe PMC

SASDS22 – Sulfite reductase flavoprotein crosslinked octamer

Sulfite reductase [NADPH] flavoprotein alpha-component

MW^experimental	585	kDa
MW^expected	530	kDa
V^Porod	767	nm³

log I(s) 5.23×10⁰ 5.23×10^-1 5.23×10^-2 5.23×10^-3

Sulfite reductase [NADPH] flavoprotein alpha-component small angle scattering data

s, nm^-1

Log plot Log-Log plot

ln I(s)

Sulfite reductase [NADPH] flavoprotein alpha-component Guinier plot

ln 5.23×10⁰ R_g: 8.4 nm 0 (8.4 nm)^-2 s²

(sR_g)²I(s)/I(0)

Sulfite reductase [NADPH] flavoprotein alpha-component Kratky plot

1.104 0 √3 sR_g

p(r)	R_g: 7.9 nm 0 D_max: 23 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

0.003
1.096

Worse

Better

Fits and models

log I(s)	s, nm^-1
+3 Δ/σ -3	s, nm^-1

Sulfite reductase [NADPH] flavoprotein alpha-component SASREF model

log I(s)	s, nm^-1
+3 Δ/σ -3	s, nm^-1

SANS data from solutions of sulfite reductase flavoprotein crosslinked octamer in 50 mM KPi, 100 mM NaCl, 1 mM EDTA, pH 7.8 were collected using the EQ-SANS (BL-6) spallation neutron source (Oak Ridge, Tennessee, USA). This sample is an octamer of His-tagged sulfite reductase flavoprotein crosslinked subunits. Three instrument configurations were used: 9 m sample-to-detector distance with 1.5 nm wavelength band, 4 m sample-to-detector distance with 0.6 nm wavelength band, and 1.3 m sample-to-detector distance with 0.4 nm wavelength band. Sample concentration: 7 mg/mL. Neutron exposure time: 3 hours / instrument configuration. Sample temperature: 8°C.

Sulfite reductase [NADPH] flavoprotein alpha-component
Mol. type		Protein
Organism		Escherichia coli (strain K12)
Olig. state		Octamer
Mon. MW		66.2 kDa

UniProt		P38038 (1-599)
Sequence		FASTA