Study of the DnaB:DciA interplay reveals insights into the primary mode of loading of the bacterial replicative helicase.

Marsin S, Adam Y, Cargemel C, Andreani J, Baconnais S, Legrand P, Li de la Sierra-Gallay I, Humbert A, Aumont-Nicaise M, Velours C, Ochsenbein F, Durand D, Le Cam E, Walbott H, Possoz C, Quevillon-Cheruel S, Ferat JL, Nucleic Acids Res (2021) Europe PMC

SASDGR5 – The Vibrio cholerae DciA/DnaB helicase complex in the presence of bound ATP (VcDnaB.DciA.ATP)

DnaB helicase complexed with ATP
DciA
MWexperimental 381 kDa
MWexpected 372 kDa
VPorod 670 nm3
log I(s) 3.29×10-1 3.29×10-2 3.29×10-3 3.29×10-4
DnaB helicase complexed with ATP DciA small angle scattering data  s, nm-1
ln I(s)
DnaB helicase complexed with ATP DciA Guinier plot ln 3.29×10-1 Rg: 5.0 nm 0 (5.0 nm)-2 s2
(sRg)2I(s)/I(0)
DnaB helicase complexed with ATP DciA Kratky plot 1.104 0 3 sRg
p(r)
DnaB helicase complexed with ATP DciA pair distance distribution function Rg: 5.0 nm 0 Dmax: 15.6 nm

Data validation


There are no models related to this curve.

Synchrotron SAXS data from solutions of the DnaB helicase hexamer/DciA complex in 20 mM Tris-HCl, 100 mM NaCl, 1 mM ATP, pH 8.8 were collected on the SWING beam line at SOLEIL (Saint-Aubin, France) using a Eiger 4M detector at a sample-detector distance of 1.8 m and at a wavelength of λ = 0.1033 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). In-line size-exclusion chromatography (SEC) SAS was employed. The SEC parameters were as follows: A 84.00 μl sample at 27.8 mg/ml was injected at a 0.50 ml/min flow rate onto a GE Superdex 200 Increase 10/300 column at 15°C. 700 successive 2.990 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 scattered intensities were displayed on an absolute scale (cm-1) using the scattering of water. Frames were examined individually using the US-SOMO HPLC module and 6 identical frames obtained at the beginning of the elution peak were averaged and further processed. The complex is constituted of one hexamer of DnaB and three monomers of DciA.

DnaB helicase complexed with ATP (DnaB.ATP)
Mol. type   Protein
Organism   Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961)
Olig. state   Hexamer
Mon. MW   52.8 kDa
 
UniProt   A0A0H3AIB6 (1-468)
Sequence   FASTA
 
DciA (DciA)
Mol. type   Protein
Organism   Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961)
Olig. state   Other
Mon. MW   18.4 kDa
 
UniProt   Q9KPH3 (1-157)
Sequence   FASTA