Crystal structure of YaeT: conformational flexibility and substrate recognition.
Gatzeva-Topalova, P.Z., Walton, T.A., Sousa, M.C.(2008) Structure 16: 1873-1881
- PubMed: 19081063 
- DOI: https://doi.org/10.1016/j.str.2008.09.014
- Primary Citation of Related Structures:  
3EFC - PubMed Abstract: 
The envelope of Gram-negative bacteria consists of inner and outer membranes surrounding the peptidoglycan wall. The outer membrane (OM) is rich in integral membrane proteins (OMPs), which have a characteristic beta barrel domain embedded in the OM. The Omp85 family of proteins, ubiquitous among Gram-negative bacteria and also present in chloroplasts and mitochondria, is required for folding and insertion of OMPs into the outer membrane. Bacterial Omp85 proteins are characterized by a periplasmic domain containing five repeats of polypeptide transport-associated (POTRA) motifs. Here we report the crystal structure of a periplasmic fragment of YaeT (the Escherichia coli Omp85) containing the first four POTRA domains in an extended conformation consistent with recent solution X-ray scattering data. Analysis of the YaeT structure reveals conformational flexibility around a hinge point between POTRA2 and 3 domains. The structure's implications for substrate binding and folding mechanisms are also discussed.
Organizational Affiliation: 
Department of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO 80309, USA.