This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1oul
From Proteopedia
Structure of the AAA+ protease delivery protein SspB
Overview
Substrate selection by AAA+ ATPases that function to unfold proteins or alter protein conformation is often regulated by delivery or adaptor proteins. SspB is a protein dimer that binds to the ssrA degradation tag and delivers proteins bearing this tag to ClpXP, an AAA+ protease, for degradation. Here, we describe the structure of the peptide binding domain of H. influenzae SspB in complex with an ssrA peptide at 1.6 A resolution. The ssrA peptides are bound in well-defined clefts located at the extreme ends of the SspB homodimer. SspB contacts residues within the N-terminal and central regions of the 11 residue ssrA tag but leaves the C-terminal residues exposed and positioned to dock with ClpX. This structure, taken together with biochemical analysis of SspB, suggests mechanisms by which proteins like SspB escort substrates to AAA+ ATPases and enhance the specificity and affinity of target recognition.
About this Structure
1OUL is a Single protein structure of sequence from Haemophilus influenzae. Full crystallographic information is available from OCA.
Reference
Structure of a delivery protein for an AAA+ protease in complex with a peptide degradation tag., Levchenko I, Grant RA, Wah DA, Sauer RT, Baker TA, Mol Cell. 2003 Aug;12(2):365-72. PMID:14536076 Page seeded by OCA on Sat May 3 04:17:54 2008
