Architectural Features of Human Mitochondrial Cysteine Desulfurase Complexes from Crosslinking Mass Spectrometry and Small-Angle X-Ray Scattering.

Cai K, Frederick RO, Dashti H, Markley JL, Structure 26(8):1127-1136.e4 (2018) Europe PMC

SASDDD3 – Human mitochondrial cysteine desulfurase-ISCU-Frataxin (NFS1, ISD11 and Acp heterodimer complex)

Cysteine desulfurase, mitochondrial
LYR motif-containing protein 4
Acyl carrier protein
Iron-sulfur cluster assembly enzyme ISCU, mitochondrial
Frataxin, mitochondrial
MWexperimental 175 kDa
MWexpected 193 kDa
VPorod 287 nm3
log I(s) 1.93×103 1.93×102 1.93×101 1.93×100
Cysteine desulfurase, mitochondrial LYR motif-containing protein 4 Acyl carrier protein Iron-sulfur cluster assembly enzyme ISCU, mitochondrial Frataxin, mitochondrial small angle scattering data  s, nm-1
ln I(s)
Cysteine desulfurase, mitochondrial LYR motif-containing protein 4 Acyl carrier protein Iron-sulfur cluster assembly enzyme ISCU, mitochondrial Frataxin, mitochondrial Guinier plot ln 1.93×103 Rg: 4.1 nm 0 (4.1 nm)-2 s2
(sRg)2I(s)/I(0)
Cysteine desulfurase, mitochondrial LYR motif-containing protein 4 Acyl carrier protein Iron-sulfur cluster assembly enzyme ISCU, mitochondrial Frataxin, mitochondrial Kratky plot 1.104 0 √3 sRg
p(r)
Cysteine desulfurase, mitochondrial LYR motif-containing protein 4 Acyl carrier protein Iron-sulfur cluster assembly enzyme ISCU, mitochondrial Frataxin, mitochondrial pair distance distribution function Rg: 4.2 nm 0 Dmax: 14.4 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Cysteine desulfurase, mitochondrial LYR motif-containing protein 4 Acyl carrier protein Iron-sulfur cluster assembly enzyme ISCU, mitochondrial Frataxin, mitochondrial HADDOCK model
SAXS data from solutions of Mitochondrial cysteine desulfurase-ISCU-Frataxin (NFS1, ISD11 and Acp heterodimer complex) in 20 mM HEPES, 150 mM NaCl, 5 mM TCEP, pH 7.5 were collected on a Bruker Nanostar instrument (Madison, WI, USA) using a MikroGap Vantec-2000 detector at a sample-detector distance of 1 m and at a wavelength of λ = 0.15418 nm (l(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). Solute concentrations ranging between 2 and 10 mg/ml were measured at 25°C. Four successive 3600 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 solution SAXS study of cysteine desulfurase complex containing ISCU and Frataxin

Cysteine desulfurase, mitochondrial (NFS1)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Dimer
Mon. MW   44.9 kDa
 
UniProt   Q9Y697 (53-457)
Sequence   FASTA
 
LYR motif-containing protein 4 (ISD11)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Dimer
Mon. MW   11.6 kDa
 
UniProt   Q9HD34
Sequence   FASTA
 
Acyl carrier protein
Mol. type   Protein
Organism   Escherichia coli
Olig. state   Dimer
Mon. MW   11.5 kDa
 
UniProt   P0A6A8
Sequence   FASTA
 
Iron-sulfur cluster assembly enzyme ISCU, mitochondrial (ISCU)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Dimer
Mon. MW   14.7 kDa
 
UniProt   Q9H1K1 (33-167)
Sequence   FASTA
 
Frataxin, mitochondrial (FXN)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Dimer
Mon. MW   14.3 kDa
 
UniProt   Q16595 (81-210)
Sequence   FASTA