Institute of
bioorganic chemistry

Scientists from the Laboratory of proteolytic enzyme chemistry IBCh RAS in collaboration with colleagues from National Cancer Institute (Frederick, USA) published the review on structural studies of ATP-dependent Lon proteases – key components of the protein quality control system. Targets of Lon proteases are mutant, damaged and some regulatory proteins. Three subfamilies have been identified in the Lon family, whose representatives are formed by ATPase domains of the AAA+ protein superfamily, serine–lysine peptidases and differing inactive extra domains. Barrel-shaped hexamers of Lon proteases bind protein targets, unfold them and translocate to an internal degradation chamber, where they undergo proteolysis. 3D analysis was used to obtain data on the structure of both individual domains and multi-domain fragments of different subfamilies’ Lon proteases. The use of cryo-electron microscopy made it possible to solve the structures of a number of full-length Lon proteases, as well as to describe the state of the enzymes at different stages of the catalytic cycle. The review is published in the Journal of Molecular Biology.