Isoleucine Binding and Regulation of Escherichia coli and Staphylococcus aureus Threonine Dehydratase (IlvA).

Yun MK, Subramanian C, Miller K, Jackson P, Radka CD, Rock CO, Biochemistry (2025) Europe PMC

SASDVE7 – Hexameric L-threonine dehydratase biosynthetic (IlvA) from Staphylococcus aureus

L-threonine dehydratase biosynthetic IlvA
MWI(0) 321 kDa
MWexpected 288 kDa
VPorod 386 nm3
log I(s) 1.00×10-2 1.00×10-3 1.00×10-4 1.00×10-5
L-threonine dehydratase biosynthetic IlvA small angle scattering data  s, nm-1
ln I(s)
L-threonine dehydratase biosynthetic IlvA Guinier plot ln 1.00×10-2 Rg: 5.1 nm 0 (5.1 nm)-2 s2
(sRg)2I(s)/I(0)
L-threonine dehydratase biosynthetic IlvA Kratky plot 1.104 0 √3 sRg
p(r)
L-threonine dehydratase biosynthetic IlvA pair distance distribution function Rg: 5.2 nm 0 Dmax: 17.1 nm

Data validation

Fits and models

log I(s)
 s, nm-1
L-threonine dehydratase biosynthetic IlvA CHIMERA model
Synchrotron SAXS data from solutions of Hexameric L-threonine dehydratase biosynthetic (IlvA) from Staphylococcus aureus in 20 mM KPO4, 200 mM NaCl, 0.1 mM TCEP,, pH 7.5 were collected on the BioCAT 18ID beam line at the Advanced Photon Source (APS), Argonne National Laboratory storage ring (Lemont, IL, USA) using a Eiger2 XE 9M detector at a sample-detector distance of 3.7 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 300.00 μl sample at 1.2 mg/ml was injected at a 0.60 ml/min flow rate onto a Cytiva Superdex 200 Increase 10/300 column at 20°C. 3600 successive 0.500 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.

L-threonine dehydratase biosynthetic IlvA (SaIlvA)
Mol. type   Protein
Organism   Staphylococcus aureus (strain USA300)
Olig. state   Hexamer
Mon. MW   48.0 kDa
 
UniProt   Q2FF63 (336-422)
Sequence   FASTA