Crystal structures of vertebrate dihydropyrimidinase and complexes from Tetraodon nigroviridis with lysine carbamylation: metal and structural requirements for post-translational modification and function.Hsieh, Y.C., Chen, M.C., Hsu, C.C., Chan, S.I., Yang, Y.S., Chen, C.J.
(2013) J.Biol.Chem. 288: 30645-30658
- PubMed: 24005677
- DOI: 10.1074/jbc.M113.496778
- Primary Citation of Related Structures:  4LCQ, 4LCR
- PubMed Abstract:
Lysine carbamylation, a post-translational modification, facilitates metal coordination for specific enzymatic activities. We have determined structures of the vertebrate dihydropyrimidinase from Tetraodon nigroviridis (TnDhp) in various states: the ...
Lysine carbamylation, a post-translational modification, facilitates metal coordination for specific enzymatic activities. We have determined structures of the vertebrate dihydropyrimidinase from Tetraodon nigroviridis (TnDhp) in various states: the apoenzyme as well as two forms of the holoenzyme with one and two metals at the catalytic site. The essential active-site structural requirements have been identified for the possible existence of four metal-mediated stages of lysine carbamylation. Only one metal is sufficient for stabilizing lysine carbamylation; however, the post-translational lysine carbamylation facilitates additional metal coordination for the regulation of specific enzymatic activities through controlling the conformations of two dynamic loops, Ala(69)-Arg(74) and Met(158)-Met(165), located in the tunnel for the substrate entrance. The substrate/product tunnel is in the "open form" in the apo-TnDhp, in the "intermediate state" in the monometal TnDhp, and in the "closed form" in the dimetal TnDhp structure, respectively. Structural comparison also suggests that the C-terminal tail plays a role in the enzymatic function through interactions with the Ala(69)-Arg(74) dynamic loop. In addition, the structures of the dimetal TnDhp in complexes with hydantoin, N-carbamyl-β-alanine, and N-carbamyl-β-amino isobutyrate as well as apo-TnDhp in complex with a product analog, N-(2-acetamido)-iminodiacetic acid, have been determined. These structural results illustrate how a protein exploits unique lysines and the metal distribution to accomplish lysine carbamylation as well as subsequent enzymatic functions.
From the Life Science Group, Scientific Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan.