Skip to ContentSkip to Navigation
About us Latest news News News articles

Puzzling structures enlightened. A structural survey of large protein complexes

14 June 2010

PhD ceremony: Mr. J.B. Bultema, 13.15 uur, Academiegebouw, Broerstraat 5, Groningen

Thesis: Puzzling structures enlightened. A structural survey of large protein complexes

Promotor(s): prof.dr. E.J. Boekema

Faculty: Mathematics and Natural Sciences


This thesis describes the results of structural characterization of large proteins complexes by single particle electron microscopy. The main aim of this project was to determine the structures of multi-protein complexes and to localize subunit positions within these multi-protein complexes. This information provides insights to better understand protein-protein interaction within complexes. One chapter describes the structural characterization of isolated mitochondrial supercomplexes. Projection maps of such supercomplexes were analysed. Based on our assignment of individual complexes in the supercomplexes we propose a structural model for the largest supercomplex. Two chapters describe several aspects of Vipp1 from Synechocystis PCC 6803. We showed that Vipp1 forms stable dimers and higher-ordered oligomers. Vipp1 is localized in the cytoplasm as well as at the cytoplasmic and thylakoid membrane. The simultaneous existence of multiple types of rings is extraordinary and suggests a special function of Vipp1. The second chapter describes a comparison with Vipp1’s bacterial homologue Phage Shock Protein A (PspA). Both proteins have similar secondary structures and form large homooligomeric rings but their ring dimensions differ significantly. Furthermore, we suggest a spatial structural model of the observed Vipp1 rings.The last chapter describes the biochemical and biophysical characterization of a ribonucleoprotein complex called Cascade. This multi-protein complex is part of the CRISPR immune system in prokaryotes which utilizes small guide RNAs to neutralize invading viruses and plasmids. We present the composition, protein stoichiometry and low-resolution structure of Cascade and show how it recognizes double-stranded DNA targets.


Last modified:13 March 2020 01.16 a.m.
View this page in: Nederlands

More news

  • 29 November 2023

    Three FSE researchers receive NWO XS grant

    Three researchers of the Faculty of Science and Engineering have been awarded an ENW-XS grant by the Dutch Research Council (Nederlandse Organisatie voor Wetenschappelijke Onderzoek, NWO): Prof. A.I. Guskov the Groningen Biomolecular Sciences and...

  • 29 November 2023

    UG professor Jayawardhana appointed scientific director DISC

    Bayu Jayawardhana has been appointed scientific director of DISC, the interuniversity research institute and graduate school that unites all university groups in the Netherlands that are active in systems and control theory and engineering. The...

  • 23 November 2023

    Two Major European grants for Groningen researchers

    Researchers Clemens Mayer and Danny Incarnato of the University of Groningen have been awarded an ERC Consolidator Grant.