Cryo-EM of polymers at near-atomic resolution: from proteins to peptides
Centar za proteomiku u suradnji sa prof.dr.sc. Danielom Kalafatović sa Tehničkog fakulteta, poziva
vas na predavanje prof. Edwarda H. Egelmana sa Sveučilišta u Virginiji, SAD.
3. 9. 2025. u 12 h u predavaonici 1 Medicinskog fakulteta u Rijeci
Prof. Egelman priznati je stručnjak u području biofizike, a posebice u korištenju krio elektronske
mikroskopije u analizi bioloških molekula, virusa i mikroorganizama.
Predavanje će se bodovati kao izborna aktivnost Doktorske škole Medicinskog fakulteta u Rijeci.
Sažetak:
Over the past 10 years, cryo-EM has emerged as the dominant technique in structural biology for
determining the atomic structure of macromolecular complexes, supplanting x-ray crystallography. For
protein polymers, it is now routine using cryo-EM to reach a near-atomic resolution, rather than
exceptional. We have been using cryo-EM to study actin, bacterial and archaeal flagellar filaments, and
bacterial and archaeal pili, among many other systems. These studies have provided new insights into
protein evolution, as well as yielding surprises. In the area of polymers formed by peptides, cryo-EM
has only appeared much more recently, and a large proportion of the literature in this area is still
dominated by techniques such as small angle x-ray scattering (SAXS) and molecular dynamics (MD).
What we have shown in many papers is that no computational methods that currently exist can predict
the complicated quaternary structure of some of these polymers, and that methods such as SAXS and
MD would be unable to determine the large asymmetric units that may arise during polymerization. For
example, a dipeptide forms a tube with an asymmetrical unit containing 18 peptides, with the peptide in
18 different conformations. The peptide studies provide insights into protein evolution, particularly the
lability of quaternary structure, as well as the potential for new materials.