Download MendeleyCrystal Structure of Arabidopsis PII Reveals Novel Structural Elements Unique to Plants.
Mizuno, Y., Berenger, B., Moorhead, G.B., Ng, K.K.(2007) Biochemistry 46: 1477-1483
- PubMed: 17279613
- DOI: https://doi.org/10.1021/bi062149e
- Primary Citation of Related Structures:
2O66, 2O67 - PubMed Abstract:
The 1.9 A resolution crystal structure of PII from Arabidopsis thaliana reveals for the first time the molecular structure of a widely conserved regulator of carbon and nitrogen metabolism from a eukaryote. The structure provides a framework for understanding the arrangement of highly conserved residues shared with PII proteins from bacteria, archaea, and red algae as well as residues conserved only in plant PII. Most strikingly, a highly conserved segment at the N-terminus that is found only in plant PII forms numerous interactions with the alpha2 helix and projects from the surface of the homotrimer opposite to that occupied by the T-loop. In addition, solvent-exposed residues near the T-loop are highly conserved in plants but differ in prokaryotes. Several residues at the C-terminus that are also highly conserved only in plants contribute part of the ATP-binding site and likely participate in an ATP-induced conformational change. Structures of PII also reveal how citrate and malonate bind near the triphosphate binding site occupied by ATP in bacterial and archaeal PII proteins.
Organizational Affiliation:
Department of Biological Sciences, University of Calgary, Calgary, Alberta, Canada T2N 1N4.
