Molecular model of a sensor of two-component signaling system

Yury Ryzhykau.

SASDK27 – SAXS data for the sensory rhodopsin II / transducer complex in detergent at 0.15 M NaCl

Sensory rhodopsin II from Natronbacterium pharaonis
Sensory rhodopsin II transducer from Natronomonas pharaonis
MWexperimental 311 kDa
MWexpected 169 kDa
log I(s) 1.28×10-1 1.28×10-2 1.28×10-3 1.28×10-4
Sensory rhodopsin II from Natronbacterium pharaonis Sensory rhodopsin II transducer from Natronomonas pharaonis small angle scattering data  s, nm-1
ln I(s)
Sensory rhodopsin II from Natronbacterium pharaonis Sensory rhodopsin II transducer from Natronomonas pharaonis Guinier plot ln 1.28×10-1 Rg: 9.0 nm 0 (9.0 nm)-2 s2
(sRg)2I(s)/I(0)
Sensory rhodopsin II from Natronbacterium pharaonis Sensory rhodopsin II transducer from Natronomonas pharaonis Kratky plot 1.104 0 3 sRg
p(r)
Sensory rhodopsin II from Natronbacterium pharaonis Sensory rhodopsin II transducer from Natronomonas pharaonis pair distance distribution function Rg: 9.8 nm 0 Dmax: 38.9 nm

Data validation


Fits and models


log I(s)
 s, nm-1
Sensory rhodopsin II from Natronbacterium pharaonis Sensory rhodopsin II transducer from Natronomonas pharaonis MEMPROT model

log I(s)
 s, nm-1
Sensory rhodopsin II from Natronbacterium pharaonis Sensory rhodopsin II transducer from Natronomonas pharaonis OTHER [STATIC IMAGE] model

Synchrotron SAXS data from solutions of the sensory rhodopsin II / transducer complex in 150 mM NaCl, 25 mM Na/Na-Pi, 1.0 mM EDTA, 0.05% DDM, pH 8 were collected on the BM29 beam line at the ESRF (Grenoble, France) using a Pilatus 1M detector at a sample-detector distance of 2.9 m and at a wavelength of λ = 0.09918 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 0.57 mg/ml was measured at 4°C. 14 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.

The protein of study is a non-fused complex of sensory rhodopsin II (NpSRII, UniProt ID P42196) with its cognate transducer (NpHtrII, UniProt ID P42259) from Nartonomonas pharaonis. The NpSRII/NpHtrII complex in 0.05% (w/v) n-Dodecyl β-D-maltoside (DDM) detergent forms dimers at 150 mM NaCl. For the "straight" model of the NpSRII/NpHtrII dimer, chi-square of the fit is 5.1. Taking into account possible conformational flexibility associated with the HAMP1, HAMP2 and Gly flexible hinges, the chi-square value can be reduced to 3.4.

Sensory rhodopsin II from Natronbacterium pharaonis (NpSRII)
Mol. type   Protein
Organism   Natronomonas pharaonis
Olig. state   Dimer
Mon. MW   26.7 kDa
 
UniProt   P42196 (1-239)
Sequence   FASTA
 
Sensory rhodopsin II transducer from Natronomonas pharaonis (NpHtrII)
Mol. type   Protein
Organism   Natronomonas pharaonis
Olig. state   Dimer
Mon. MW   57.8 kDa
 
UniProt   P42259 (3-534)
Sequence   FASTA