Assembly principles of a unique cage formed by hexameric and decameric E. coli proteins
Hélène Malet,
Kaiyin Liu,
Majida El Bakkouri,
Sze Wah Samuel Chan,
Gregory Effantin,
Maria Bacia,
Walid A Houry,
Irina Gutsche
Affiliations
Hélène Malet
European Molecular Biology Laboratory, Grenoble, France; Unit for Virus Host-Cell Interactions, Université Grenoble Alpes, Grenoble, France; Unit for Virus Host-Cell Interactions, CNRS, Grenoble, France
Kaiyin Liu
Department of Biochemistry, University of Toronto, Toronto, Canada
Majida El Bakkouri
Department of Biochemistry, University of Toronto, Toronto, Canada
Sze Wah Samuel Chan
Department of Biochemistry, University of Toronto, Toronto, Canada
Gregory Effantin
Unit for Virus Host-Cell Interactions, Université Grenoble Alpes, Grenoble, France; Unit for Virus Host-Cell Interactions, CNRS, Grenoble, France
Maria Bacia
Université Grenoble Alpes, Institut de Biologie Structurale, Grenoble, France; Institut de Biologie Structurale, CNRS, Grenoble, France; Institut de Biologie Structurale, CEA, Grenoble, France
Walid A Houry
Department of Biochemistry, University of Toronto, Toronto, Canada
Irina Gutsche
Unit for Virus Host-Cell Interactions, Université Grenoble Alpes, Grenoble, France; Unit for Virus Host-Cell Interactions, CNRS, Grenoble, France
A 3.3 MDa macromolecular cage between two Escherichia coli proteins with seemingly incompatible symmetries–the hexameric AAA+ ATPase RavA and the decameric inducible lysine decarboxylase LdcI–is reconstructed by cryo-electron microscopy to 11 Å resolution. Combined with a 7.5 Å resolution reconstruction of the minimal complex between LdcI and the LdcI-binding domain of RavA, and the previously solved crystal structures of the individual components, this work enables to build a reliable pseudoatomic model of this unusual architecture and to identify conformational rearrangements and specific elements essential for complex formation. The design of the cage created via lateral interactions between five RavA rings is unique for the diverse AAA+ ATPase superfamily.
