Structure of the archaeal pab87 peptidase reveals a novel self-compartmentalizing protease family
Delfosse, V., Girard, E., Birck, C., Delmarcelle, M., Delarue, M., Poch, O., Schultz, P., Mayer, C.(2009) PLoS One 4: e4712-e4712
- PubMed: 19266066 
- DOI: https://doi.org/10.1371/journal.pone.0004712
- Primary Citation of Related Structures:  
2QMI - PubMed Abstract: 
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.
Organizational Affiliation: 
Centre de Recherche des Cordeliers, LRMA, INSERM UMR-S 872, Université Pierre et Marie Curie, Paris, France.