Salt bridges at the subdomain interfaces of the adenylation domain and active-site residues of Mycobacterium tuberculosis NAD + -dependent DNA ligase A (MtbLigA) are important for the initial steps of nick-sealing activity

Afsar M, Shukla A, Kumar N, Ramachandran R, Acta Crystallographica Section D Structural Biology 77(6) (2021) DOI

SASDG65 – Adenylation domain of DNA ligase A (LigA)

DNA ligase A
MWexperimental 37 kDa
MWexpected 37 kDa
VPorod 68 nm3
log I(s) 5.16×104 5.16×103 5.16×102 5.16×101
DNA ligase A small angle scattering data  s, nm-1
ln I(s)
DNA ligase A Guinier plot ln 5.16×104 Rg: 2.7 nm 0 (2.7 nm)-2 s2
DNA ligase A Kratky plot 1.104 0 3 sRg
DNA ligase A pair distance distribution function Rg: 2.7 nm 0 Dmax: 8.9 nm

Data validation

Fits and models

log I(s)
 s, nm-1
DNA ligase A GASBOR model

SAXS data from solutions of the adenylation domain of DNA ligase A in 50 mM Tris-HCl 200 mM NaCl 2 mM β-mercaptoethanol, pH 8 were collected using an Anton Paar SAXSpace at the CSIR-Central Drug Research Institute (Lucknow India) with a Mythen2 R 1K detector at a sample-detector distance of 0.3 m and at a wavelength of λ = 0.154 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 12.50 mg/ml was measured at 10°C. Two successive 1800 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.

DNA ligase A (AdD)
Mol. type   Protein
Organism   Mycobacterium tuberculosis
Olig. state   Monomer
Mon. MW   36.7 kDa
UniProt   P9WNV1 (1-328)
Sequence   FASTA