Table II. Calculated and native masses of complex II subunits and subcomplexes in Arabidopsis

n.i., Not identified.

SubunitAccession No.aCalculated Mass PrecursorbCalculated Mass Matureb,cApparent MassdHolo Complex IISubcomplex IIaSubcomplex IIbSubcomplex IIc
kDkDkD
SDH1At5g6676069.65666.04365++
At2g1845069.36365.745
SDH2At3g2738031.17128.25329++
At5g4065031.14128.143
At5g6516534.983n.i.
SDH3At5g0960023.45412.17212++
At4g3221023.45412.172
SDH4At2g4650516.8429.1816++
SDH5At1g4742028.10618.41718++
SDH6At1g0848015.81315.68215++
SDH7At3g4783310.2987.0957++
At5g6257510.8607.485
SDH8At2g463904.8844.8845+n.i.
Σ calculated mass (kD)e161.7161.794.344.1 + SDH8f18.4
Σ apparent mass (kD)e1571579440 + SDH8f18
  • a Accession numbers according to TAIR (https://www.arabidopsis.org/). Note that two isoforms are present for SDH1, SDH3, and SDH7 and three isoforms are present for SDH2.  bMolecular masses were calculated using the ProtParam tool (http://web.expasy.org/protparam/).  cFor definition of the mature sequences, see Supplemental Figure S4.  dApparent molecular masses as determined by Millar et al. (2004).  eMolecular masses for the holo complex and subcomplexes IIa, IIb, and IIc were determined considering their subunit compositions. Subunit masses were summed using the first isoform given in this table.  fNote that inclusion of SDH8 in subcomplex IIb is not clear.