4-Aminopyridinium 5-carboxypentanoate monohydrate

In the title hydrated salt, C5H7N2+·C6H9O4−·H2O, the carboxy H atom is disordered over two positions with equal occupancy. In the crystal, O atoms of the 5-carboxypentanoate anion link the 4-aminopyridinium cations and water molecules into a three-dimensional network via N—H...O hydrogen bonds. The crystal structure is further consolidated by O—H...O hydrogen bonds involving the anion and the solvent water molecule.