【Seminar】“High-resolution structures of viruses and their proteins obtained by cryo-EM”

Speaker:

Dr. Andrei Moiseenko

Professor Olga Sokolova

Moscow Lomonosov State University

October 2^nd, 2023

11:00 – 12:00
@ C210, Center Bldg

“High-resolution structures of viruses

 and their proteins obtained by cryo-EM”

Abstract          

We present the cryo EM structures of formaldehyde inactivated tick-borne encephalitis virus and viral chaperonins. High-resolution reconstruction of TBEV reveals the structural integrity of the envelope proteins, specifically the E protein ectodomains. The comparative study shows high structural similarity with other strains. We perform local variability analysis on the small parts of the envelope protein shell and demonstrated asymmetry of inactivated virions and the deformations of the membrane profile.

A symmetry-free cryo-EM structures of a single-ring chaperonins encoded by the gene 246 of bacteriophage OBP Pseudomonas fluorescens, and gene 288 of Bacillus subtilis bacteriophage AR9 in the nucleotide-free, ATPγS-, and ADP-bound states demonstrate a unique subunit arrangement, with two possible conformations, differing in nucleotide-binding affinity. The binding of nucleotides results in the increase of subunits’ conformational variability. Due to its unique structural and functional features, viral chaperonins can represent a new group.