A monomeric mycobacteriophage immunity repressor utilizes two domains to recognize an asymmetric DNA sequence.

McGinnis RJ, Brambley CA, Stamey B, Green WC, Gragg KN, Cafferty ER, Terwilliger TC, Hammel M, Hollis TJ, Miller JM, Gainey MD, Wallen JR, Nat Commun 13(1):4105 (2022) Europe PMC

SASDML3 – Mycobacterium phage TipsytheTRex immunity repressor bound to 24mer DNA

Immunity repressor
24mer dsDNA
MWexperimental 27 kDa
MWexpected 36 kDa
VPorod 43 nm3
log I(s) 4.61×101 4.61×100 4.61×10-1 4.61×10-2
Immunity repressor 24mer dsDNA small angle scattering data  s, nm-1
ln I(s)
Immunity repressor 24mer dsDNA Guinier plot ln 4.61×101 Rg: 2.4 nm 0 (2.4 nm)-2 s2
Immunity repressor 24mer dsDNA Kratky plot 1.104 0 3 sRg
Dmax: 9 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Immunity repressor 24mer dsDNA BILBOMD model

Synchrotron SAXS data from solutions of Mycobacterium phage TipsytheTRex immunity repressor bound to 24mer DNA in 20 mM Tris pH 7.5, 0.5 M NaCl, 1 mM DTT, were collected on the 12.3.1 (SIBYLS) beam line at the Advanced Light Source (ALS; Berkeley, CA, USA) using a Pilatus3 X 2M detector at a sample-detector distance of 2.1 m and at a wavelength of λ = 0.1127 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 3.00 mg/ml was measured at 20°C. 600 successive 3 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.

Immunity repressor
Mol. type   Protein
Organism   Mycobacterium phage TipsytheTRex
Olig. state   Monomer
Mon. MW   21.4 kDa
UniProt   A0A2D1GKF7 (1-183)
Sequence   FASTA
24mer dsDNA
Mol. type   DNA
Olig. state   Monomer
Mon. MW   14.9 kDa
Sequence   FASTA