AI Article Synopsis
- The outer membrane proteins (Omps) are crucial for bacterial survival and play a role in virulence, with OmpW being notable for having well-defined extracellular loops in its crystal structure compared to other E. coli Omps.
- OmpW's polypeptide backbone was studied using 30-Fos micelles, leading to complete backbone NMR assignments and a detailed structural characterization of its loops.
- The findings, which included comparisons with the crystal structure and NMR data, revealed that the extracellular loops of OmpW maintain their secondary structure while experiencing slow movements at the detergent-solvent interface.
Article Abstract
The outer membrane proteins (Omps) are key factors for bacterial survival and virulence. Among the Omps that have been structurally characterized either by X-ray crystallography or by NMR in solution, the crystal structure of OmpW stands out because three of its four extracellular loops are well defined, whereas long extracellular loops in other E. coli Omps are disordered in the crystals as well as in NMR structures. OmpW thus presented an opportunity for a detailed comparison of the extracellular loops in a β-barrel membrane protein structure in crystals and in noncrystalline milieus. Here, the polypeptide backbone conformation of OmpW in 30-Fos micelles was determined. Complete backbone NMR assignments were obtained and the loops were structurally characterized. In combination with the OmpW crystal structure, NMR line shape analyses, and (15)N{(1)H}-NOE data, these results showed that intact regular secondary structures in the loops undergo slow hinge motions at the detergent-solvent interface.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4150354 | PMC |
| http://dx.doi.org/10.1016/j.str.2014.05.016 | DOI Listing |
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