2qmi

Publication Abstract from PubMed

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.

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 PLoS One. 2009;4(3):e4712. Epub 2009 Mar 5. PMID:19266066^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.