Regulation of futile ligation during early steps of BER in M. tuberculosis is carried out by a β-clamp-XthA-LigA tri-component complex

Shukla A, Afsar M, Khanam T, Kumar N, Ali F, Kumar S, Jahan F, Ramachandran R, International Journal of Biological Macromolecules (2022) DOI

SASDFE6 – Sliding beta clamp

Beta sliding clamp
MWexperimental 90 kDa
MWexpected 86 kDa
VPorod 186 nm3
log I(s) 9.37×100 9.37×10-1 9.37×10-2 9.37×10-3
Beta sliding clamp small angle scattering data  s, nm-1
ln I(s)
Beta sliding clamp Guinier plot ln 9.37×100 Rg: 3.7 nm 0 (3.7 nm)-2 s2
(sRg)2I(s)/I(0)
Beta sliding clamp Kratky plot 1.104 0 √3 sRg
p(r)
Beta sliding clamp pair distance distribution function Rg: 3.7 nm 0 Dmax: 10.3 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Beta sliding clamp GASBOR model
Synchrotron SAXS data from solutions of sliding beta clamp in 50 mM Tris pH 8.0, 200 mM NaCl , 2 mM β-mercaptoethanol, were collected on the BM29 beam line at the ESRF storage ring (Grenoble, France) using a Pilatus 1M detector at a sample-detector distance of 2.9 m and at a wavelength of λ = 0.0992 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 2.00 mg/ml was measured at 10°C. 10 successive 1 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 sample shows signs of severe aggregation.

Beta sliding clamp
Mol. type   Protein
Organism   Mycobacterium tuberculosis
Olig. state   Dimer
Mon. MW   42.9 kDa
 
UniProt   P9WNU1 (1-402)
Sequence   FASTA