Structural Basis for pH-Dependent Oligomerization of Dihydropyrimidinase from Pseudomonas aeruginosa PAO1

Figure 5

The structure of P. aeruginosa dihydropyrimidinase tetramer. An asymmetric unit contains four crystallographically independent P. aeruginosa dihydropyrimidinase monomers B-A-C-D. Crystallographically related tetramer B-A-C′-D′ was formed and further stabilized via many hydrogen bonds and salt bridges. This tetramerization structure was similar to that of Thermus sp. dihydropyrimidinase (PDB entry 1GKQ).