Fig. 8. (A) Chemical structures of agrocin 84, its toxic moiety (TM84), agrocinopine A and leucyl-adenylate. Pyranose-2-phosphate groups shared by agrocin and agrocinopine A are highlighted with red dashed polygons. Groups of atoms that are different between TM84 and leucyl-adenylate are shown in red. The black arrow indicates a nonhydrolyzable P–N bond in TM84. (B) The scheme showing the biosynthesis, transport, and mode of action of agrocin 84. IM – inner membrane, OM – outer membrane, BGC – biosynthetic gene cluster, LeuRS – leucyl-tRNA synthetase. (C) The details of the interaction between agrocin 84/agrocinopine A with the periplasmic solute binding protein (PBP) AccA (PDB IDs: 4ZEC/4ZEB).¹⁰⁹ Agrocinopine is coloured gold, agrocin 84 is green. Amino acid residues interacting with d-glucopyranose-2-phosphate moiety of agrocin are shown in the left corner. Hydrogen bonds are shown as black dashed lines. (D) The crystal structure of the ternary complex of LeuRS, TM84 and tRNA^Leu (PDB ID: 3ZGZ).¹¹⁸ Selected amino acid residues involved in the binding of TM84 in the active site of LeuRS are shown in the left corner together with the two 3′-terminal nucleotides of the tRNA^Leu acceptor stem. TM84 is green, tRNA^Leu is orange.