Combination of SAXS and Protein Painting Discloses the Three-Dimensional Organization of the Bacterial Cysteine Synthase Complex, a Potential Target for Enhancers of Antibiotic Action.

Rosa B, Marchetti M, Paredi G, Amenitsch H, Franko N, Benoni R, Giabbai B, De Marino MG, Mozzarelli A, Ronda L, Storici P, Campanini B, Bettati S, Int J Mol Sci 20(20) (2019) Europe PMC

SASDGV6 – Cysteine synthase A

Cysteine synthase A
MWexperimental 72 kDa
MWexpected 71 kDa
VPorod 108 nm3
log I(s) 6.71×100 6.71×10-1 6.71×10-2 6.71×10-3
Cysteine synthase A small angle scattering data  s, nm-1
ln I(s)
Cysteine synthase A Guinier plot ln 6.71×100 Rg: 2.6 nm 0 (2.6 nm)-2 s2
(sRg)2I(s)/I(0)
Cysteine synthase A Kratky plot 1.104 0 √3 sRg
p(r)
Cysteine synthase A pair distance distribution function Rg: 2.6 nm 0 Dmax: 8.5 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Cysteine synthase A DAMMIN model
Synchrotron SAXS data from solutions of cysteine synthase in 20 mM sodium phosphate, 85 mM NaCl, 2 mM EDTA, 10 mM 2-MCE, pH 7.5 were collected on the Austrian SAXS beamline 5.2L beam line at the ELETTRA Sincrotrone Trieste storage ring (Trieste, Italy) using a Dectris / Pilatus3 1M detector at a sample-detector distance of 1.2 m and at a wavelength of λ = 0.15 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 1.20 mg/ml was measured at 20°C. 12 successive 10 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.

Cysteine synthase A (CysK)
Mol. type   Protein
Organism   Escherichia coli
Olig. state   Dimer
Mon. MW   35.7 kDa
 
UniProt   P0ABK5 (1-323)
Sequence   FASTA