CCEMMP Seminar Series

The CCeMMP are running a monthly research seminar series for interested researchers, research staff, students and enthusiasts. The seminar will be based mainly around cryo-electron microscopy of/and membrane proteins with a mixture of domestic and international speakers in this field. Speakers will be announced monthly with a calendar invitation with speaker and virtual details.

The seminar will be held at 10:00-11:00am AEDT/AEST on every second Tuesday of each month. If you would like to be invited to the seminars, please register to this event and the Centre Manager will send you calendar invitations.

 

Seminar dates for 2022 will commence from 8th February 2022 AEDT/AEST.

Past seminars

14 December 2021

Dr Doreen Matthies

Earl Stadtman tenure track investigator

Head, Unit on Structural Biology

Division of Basic and Translational Biophysics

Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

Cryo-EM of membrane proteins:
What have we learned in the last decades and what are the challenges?

In the last decade the field of Structural Biology has made great advances in using electron microscopy to solve structures of protein complexes including membrane proteins to high resolution. Best practices of how to use Single Particle Cryo-EM and more importantly how to optimize a membrane protein sample such as an ion channel or a transporter will be discussed. Most membrane protein structures are currently resolved in a detergent micelle, but cryo-EM also makes it possible to look at membrane protein complexes in a lipid bilayer, such as synthetic or native lipid nanodiscs, liposomes, or even inside cells now. A brief introduction to each of these techniques will be discussed with examples of the conformational landscape of magnesium channel CorA, voltage-gated potassium channel Kv1.2-2.1, a human excitatory amino acid transporter and more.

Using cryo-EM to interrogate the structure and dynamics of GPCRs

Cryo-electron microscopy (cryo-EM) continues to grow as a powerful method for structural studies of biomolecules and their complexes. Nowadays, it can routinely determine molecular structures with resolutions in the 2.5 – 3.5 Å range. Such results are adequate for modelling of the protein but lack fidelity for confident localization of water molecules and hydrogen atoms. Unambiguous elucidation of the biochemistry behind protein function and pharmacology of drugs would require atomic resolution structures, at levels below 1.5 Å. Last year, several groups worldwide demonstrated atomic resolution cryo-EM with a test sample comprising the “easy” soluble protein apoferritin. This was an important technological milestone showcasing the best-case-scenario capabilities of cryo-EM. However, membrane proteins, and other real-world samples, impose numerous experimental challenges, such as small size, heterogeneity, flexibility, preferential orientation, etc. 

9 November 2021

Professor Radostin Danev

Advanced Structural Studies

Graduate School of Medicine, The University of Tokyo

12 October 2021

Professor Patrick Sexton

Director, ARC Centre for Cryo-electron Microscopy of Membrane Proteins; 

Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University

Using cryo-EM to interrogate the structure and dynamics of GPCRs

G protein-coupled receptors (GPCRs) are the largest superfamily of cell surface receptor proteins and a major target class for drug development. GPCRs are inherently flexible proteins that have evolved to allosterically communicate external signals to modulation of cellular function through recruitment and activation of transducer proteins, particularly G proteins. Technological evolution in cryo-EM combined with continuing advances in biochemical approaches for the stabilisation of active-state complexes of GPCRs with different transducer proteins is now enabling structural interrogation of receptor activation and transducer engagement. Moreover, cryo-EM can access conformational ensembles of GPCR complexes that are present during vitrification, which can provide a window into the dynamics of these complexes.