Assembly principles of a unique cage formed by hexameric and decameric E. coli proteins

Hélène Malet (1) , Kaiyin Liu (2) , Majida El Bakkouri (1) , Sze Wah Samuel Chan (2) , Grégory Effantin (3) , Maria Bacia-Verloop (3) , Walid A Houry (2) , Irina Gutsche (1)

1 UVHCI - Unit of Virus Host Cell Interactions = Biologie structurale des interactions entre virus et cellule hôte
2 Department of Biochemistry [University of Toronto]
3 IBS - UMR 5075 - Institut de biologie structurale

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.

Domaines: Sciences du Vivant [q-bio]

Hélène Malet, Kaiyin Liu, Majida El Bakkouri, Sze Wah Samuel Chan, Grégory Effantin, et al.. Assembly principles of a unique cage formed by hexameric and decameric E. coli proteins. eLife, 2014, pp.e03653. ⟨10.7554/eLife.03653⟩. ⟨hal-01100506⟩