Friday, November 9, 2007

Heme not required for Complex II function, important for stability

Tran QM, Rothery RA, Maklashina E, Cecchini G, Weiner JH.
Escherichia coli succinate dehydrogenase variant lacking the heme b.
Proc Natl Acad Sci U S A. 2007 Nov 7; [Epub ahead of print]

Wednesday, September 12, 2007

Glutathionylation of CII flavoprotein reduces ROS production, lost in ischemia/reperfusion injury

Yeong-Renn Chen, Chwen-Lih Chen, Douglas R Pfeiffer, and Jay L. Zweier
Mitochondrial complex II in post-ischemic heart: Oxidative injury and the role of protein S-glutathionylation
J. Biol. Chem, 10.1074/jbc.M702294200
(Complex II was glutathionylated at C90 which is C46 in the mature sequence, 10 residues from the FAD covalent attachment site and spatially near the surface and near the adenine end of FAD. )

Thursday, July 26, 2007

New Q-site article

Szeto SS, Reinke SN, Sykes BD, Lemire BD. Ubiquinone-binding site mutations in the saccharomyces cerevisiae succinate dehydrogenase generate superoxide and lead to the accumulation of succinate.
J Biol Chem. 2007 Jul 18; PMID: 17636259

Firmer evidence for involvement of Complex II in Huntingtons

Benchoua A, Trioulier Y, Zala D, Gaillard MC, Lefort N, Dufour N, Saudou F, Elalouf JM, Hirsch E, Hantraye P, Déglon N, Brouillet E.
Involvement of mitochondrial complex II defects in neuronal death produced by N-terminus fragment of mutated huntingtin.
Mol Biol Cell. 2006 Apr;17(4):1652-63.

Friday, June 1, 2007

New Article

Baysal BE, Lawrence EC, Ferrell RE.
Sequence variation in human succinate dehydrogenase genes: evidence for long-term balancing selection on SDHA.
BMC Biol. 2007 Mar 21;5:12. PMID: 17376234

New Complex II Polymorphism database:

Database address:
http://chromium.liacs.nl/lovd_sdh/
Publication:
Jean-Pierre Bayley, Peter Devilee1, and Peter EM Taschner.(2005) The SDH mutation database: an online resource for succinate dehydrogenase sequence variants involved in pheochromocytoma, paraganglioma and mitochondrial complex II deficiency
BMC Medical Genetics 2005, 6:39 doi:10.1186/1471-2350-6-39

Thursday, May 10, 2007

Wolinella succinogenes QFR has a cis-Asp!

(larger image) Wolinella succinogenes QFR flavoprotein has a cis-Asp! Model w atom labels is 2BS2, maps calculated with phases from it using SF's sf2bs2.cif. Other model is chicken complex II, superimposing the FAD domain. Green and red maps are positively and negatively contoured Fo-Fc maps- green on the chickenmodel shows where the atom should be, red on the Wolli atom shows it is misplaced. Apparently this cis-peptide occurs in all membrane-bound SDH/QFR enzymes solved to date. Soluble FCc FRD from Shewanella has a deletion here and no cis-peptide. The cis-peptide introduces a bulge which accomodates the extra residue. This is near the active site and an enigmatic conserved protein-bound metal ion (yellow crosses at bottom center).

Saturday, March 24, 2007

Recent Article

Dicoumarol impairs mitochondrial electron transport and pyrimidine biosynthesis in human myeloid leukemia HL-60 cells. Biochem Pharmacol. 2007 Feb 1;73(3):427-39. Epub 2006 Oct 21. PMID: 17123468 (Dicoumarol stimulates ROS production, potentiated by Complex II Q-site inhibitors.)

Wednesday, March 7, 2007

Recent Article

Bacsi A, Woodberry M, Widger W, Papaconstantinou J, Mitra S, Peterson JW, Boldogh I. Localization of superoxide anion production to mitochondrial electron transport chain in 3-NPA-treated cells. Mitochondrion. 2006 Oct;6(5):235-44.
PMID: 17011837

Tuesday, February 20, 2007

For Comments:

Only moderators can initiate new posts. Anyone can add a comment to an existing post, but the comment should be related. So this entry is for general comments not related to any of the articles. Also for instructions to new users.

Thursday, February 15, 2007

New Article:

Silkin Y, Oyedotun KS, Lemire BD.
The role of Sdh4p Tyr-89 in ubiquinone reduction by the Saccharomyces cerevisiae succinate dehydrogenase.
Biochim Biophys Acta. 2006 Dec 6; [Epub ahead of print]
PMID: 17208193
Tran QM, Rothery RA, Maklashina E, Cecchini G, Weiner JH.
The quinone binding site in Escherichia coli succinate dehydrogenase is required for electron transfer to the heme b.
J Biol Chem. 2006 Oct 27;281(43):32310-7