The structure of a PII signaling protein from a halophilic archaeon reveals novel traits and high-salt adaptations

Empreu sempre aquest identificador per citar o enllaçar aquest ítem
Información del item - Informació de l'item - Item information
Títol: The structure of a PII signaling protein from a halophilic archaeon reveals novel traits and high-salt adaptations
Autors: Palanca, Carles | Pedro Roig, Laia | Llácer, José Luis | Camacho, Mónica | Bonete, María-José | Rubio, Vicente
Grups d'investigació o GITE: Biotecnología de Extremófilos (BIOTECEXTREM)
Centre, Departament o Servei: Universidad de Alicante. Departamento de Agroquímica y Bioquímica
Paraules clau: Cell signaling | Crystal structure | GlnK | Haloadaptation | Haloferax mediterranei
Àrees de coneixement: Bioquímica y Biología Molecular
Data de publicació: d’agost-2014
Editor: Wiley
Citació bibliogràfica: FEBS Journal. 2014, 281(15): 3299-3314. doi:10.1111/febs.12881
Resum: To obtain insights into archaeal nitrogen signaling and haloadaptation of the nitrogen/carbon/energy-signaling protein PII, we determined crystal structures of recombinantly produced GlnK2 from the extreme halophilic archaeon Haloferax mediterranei, complexed with AMP or with the PII effectors ADP or ATP, at respective resolutions of 1.49 Å, 1.45 Å, and 2.60 Å. A unique trait of these structures was a three-tongued crown protruding from the trimer body convex side, formed by an 11-residue, N-terminal, highly acidic extension that is absent from structurally studied PII proteins. This extension substantially contributed to the very low pI value, which is a haloadaptive trait of H. mediterranei GlnK2, and participated in hexamer-forming contacts in one crystal. Similar acidic N-extensions are shown here to be common among PII proteins from halophilic organisms. Additional haloadaptive traits prominently represented in H. mediterranei GlnK2 are a very high ratio of small residues to large hydrophobic aliphatic residues, and the highest ratio of polar to nonpolar exposed surface for any structurally characterized PII protein. The presence of a dense hydration layer in the region between the three T-loops might also be a haloadaptation. Other unique findings revealed by the GlnK2 structure that might have functional relevance are: the adoption by its T-loop of a three-turn α-helical conformation, perhaps related to the ability of GlnK2 to directly interact with glutamine synthetase; and the firm binding of AMP, confirmed by biochemical binding studies with ATP, ADP, and AMP, raising the possibility that AMP could be an important PII effector, at least in archaea.
Patrocinadors: This work was supported by grants from the Spanish government (BFU2011-30407 and BIO2008_00082, to V. Rubio and M. J. Bonete, respectively) and from the Valencian government (Prometeo 2009/51 to V. Rubio). C. Palanca is a JAE-Predoc fellow of the CSIC and, during this work, L. Pedro-Roig was a FPU fellow of the Spanish Ministry of Education. The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007–2013) under BioStruct-X (grant agreement No. 283570).
ISSN: 1742-464X (Print) | 1742-4658 (Online)
DOI: 10.1111/febs.12881
Idioma: eng
Tipus: info:eu-repo/semantics/article
Drets: © 2014 FEBS
Revisió científica: si
Versió de l'editor:
Apareix a la col·lecció: Investigacions finançades per la UE
INV - BIOTECEXTREM - Artículos de Revistas

Arxius per aquest ítem:
Arxius per aquest ítem:
Arxiu Descripció Tamany Format  
Thumbnail2014_Palanca_etal_FEBS_final.pdfVersión final (acceso restringido)1,39 MBAdobe PDFObrir     Sol·licitar una còpia
Thumbnail2014_Palanca_etal_FEBS_accepted.pdfAccepted Manuscript (acceso abierto)556,22 kBAdobe PDFObrir Vista prèvia

Tots els documents dipositats a RUA estan protegits per drets d'autors. Alguns drets reservats.