Fig. 2: Structure of the DrrA:Rab8a complex.
From: Rab1-AMPylation by Legionella DrrA is allosterically activated by Rab1
a Orthogonal views of the Rab8-DrrA complex. Pink spheres denote the catalytic Asp residues of DrrA. The green sphere represents the Mg2+ ion. b Linker density from the unbiased simulated-annealing omit DFo-Fc electron density map contoured at 2.5 σ. The R subscript denotes Rab8a, and the D subscript denotes DrrA. c Schematic representation of the Rab8-DrrA interface. Interactions are shown with dashed lines; hydrogen bonds are blue and salt bridges are red. The corresponding interaction residues in Rab1 are shown in the panel on the right. Important residues for maintaining enzymatic activity are coloured cyan, and ‘α’ represents α-helix. d Demonstration of the conventional site (RBS1, containing the catalytic centre) and non-conventional site (RBS2, the back face of the catalytic centre. e Structural comparison between the catalytic centre in GS-ATase (PDB: 3K7D, green) and the catalytic centre in DrrA in the DrrA-Rab8a complex. The catalytic centre of DrrA includes D110DrrA, D112DrrA and D150DrrA. The catalytic centre of GS-AT includes D701GS-AT, D703GS-AT and D753GS-AT. f Structural superposition of free AMP-Rab1:GppNHp (PDB: 3NKV, yellow) and Rab8a (PDB: 4LHW, pink) with Rab8a (blue) from the complex with DrrA. Green spheres indicate Mg2+ ions, and GppNHp is shown in stick representation.
