Structure of the archaeal pab87 peptidase reveals a novel self-compartmentalizing protease family.
Fiche publication
Date publication
janvier 2009
Auteurs
Membres identifiés du Cancéropôle Est :
Dr BIRCK Catherine, Dr POCH Olivier, Dr SCHULTZ Patrick
Tous les auteurs :
Delfosse V, Girard E, Birck C, Delmarcelle M, Delarue M, Poch O, Schultz P, Mayer C
Lien Pubmed
Résumé
Self-compartmentalizing proteases orchestrate protein turnover through an original architecture characterized by a central catalytic chamber. Here we report the first structure of an archaeal member of a new self-compartmentalizing protease family forming a cubic-shaped octamer with D(4) symmetry and referred to as CubicO. We solved the structure of the Pyrococcus abyssi Pab87 protein at 2.2 A resolution using the anomalous signal of the high-phasing-power lanthanide derivative Lu-HPDO3A. A 20 A wide channel runs through this supramolecular assembly of 0.4 MDa, giving access to a 60 A wide central chamber holding the eight active sites. Surprisingly, activity assays revealed that Pab87 degrades specifically d-amino acid containing peptides, which have never been observed in archaea. Genomic context of the Pab87 gene showed that it is surrounded by genes involved in the amino acid/peptide transport or metabolism. We propose that CubicO proteases are involved in the processing of d-peptides from environmental origins.
Référence
PLoS ONE. 2009;4(3):e4712