2o66
From Proteopedia
Crystal Structure of Arabidopsis thaliana PII bound to citrate
Structural highlights
FunctionGLNB_ARATH Participates in sensing carbon and organic nitrogen status and regulates some steps of primary carbon and nitrogen metabolism. Required for nitrite uptake in chloroplasts and regulates arginine biosynthesis through interaction with acetylglutamate kinase (NAGK) in chloroplasts. Regulates fatty acids synthesis in chloroplasts by interacting with the acetyl-CoA carboxylase complex and inhibiting acetyl-CoA carboxylase (ACCase) activity.[1] [2] [3] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe 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. Crystal structure of Arabidopsis PII reveals novel structural elements unique to plants.,Mizuno Y, Berenger B, Moorhead GB, Ng KK Biochemistry. 2007 Feb 13;46(6):1477-83. PMID:17279613[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||||
