| Structural highlights
6wxi is a 3 chain structure with sequence from Ecoli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Related: | |
| Gene: | tolC, colE1-i, mtcB, mukA, refI, toc, weeA, b3035, JW5503 (ECOLI) |
| Resources: | FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT |
Function
[TOLC_ECOLI] Outer membrane channel, which is required for the function of several efflux systems such as AcrAB-TolC, AcrEF-TolC, EmrAB-TolC and MacAB-TolC. These systems are involved in export of antibiotics and other toxic compounds from the cell. TolC is also involved in import of colicin E1 into the cells.[1] [2] [3] [4] [5]
Publication Abstract from PubMed
The double membrane architecture of Gram-negative bacteria forms a barrier that is impermeable to most extracellular threats. Bacteriocin proteins evolved to exploit the accessible, surface-exposed proteins embedded in the outer membrane to deliver cytotoxic cargo. Colicin E1 is a bacteriocin produced by, and lethal to, Escherichia coli that hijacks the outer membrane proteins (OMPs) TolC and BtuB to enter the cell. Here, we capture the colicin E1 translocation domain inside its membrane receptor, TolC, by high-resolution cryo-electron microscopy to obtain the first reported structure of a bacteriocin bound to TolC. Colicin E1 binds stably to TolC as an open hinge through the TolC pore-an architectural rearrangement from colicin E1's unbound conformation. This binding is stable in live E. coli cells as indicated by single-molecule fluorescence microscopy. Finally, colicin E1 fragments binding to TolC plug the channel, inhibiting its native efflux function as an antibiotic efflux pump, and heightening susceptibility to three antibiotic classes. In addition to demonstrating that these protein fragments are useful starting points for developing novel antibiotic potentiators, this method could be expanded to other colicins to inhibit other OMP functions.
Colicin E1 opens its hinge to plug TolC.,Budiardjo SJ, Stevens JJ, Calkins AL, Ikujuni AP, Wimalasena VK, Firlar E, Case DA, Biteen JS, Kaelber JT, Slusky JSG Elife. 2022 Feb 24;11. pii: 73297. doi: 10.7554/eLife.73297. PMID:35199644[6]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Morona R, Manning PA, Reeves P. Identification and characterization of the TolC protein, an outer membrane protein from Escherichia coli. J Bacteriol. 1983 Feb;153(2):693-9. PMID:6337123
- ↑ Kobayashi K, Tsukagoshi N, Aono R. Suppression of hypersensitivity of Escherichia coli acrB mutant to organic solvents by integrational activation of the acrEF operon with the IS1 or IS2 element. J Bacteriol. 2001 Apr;183(8):2646-53. PMID:11274125 doi:http://dx.doi.org/10.1128/JB.183.8.2646-2653.2001
- ↑ Touze T, Eswaran J, Bokma E, Koronakis E, Hughes C, Koronakis V. Interactions underlying assembly of the Escherichia coli AcrAB-TolC multidrug efflux system. Mol Microbiol. 2004 Jul;53(2):697-706. PMID:15228545 doi:http://dx.doi.org/10.1111/j.1365-2958.2004.04158.x
- ↑ Lin HT, Bavro VN, Barrera NP, Frankish HM, Velamakanni S, van Veen HW, Robinson CV, Borges-Walmsley MI, Walmsley AR. MacB ABC transporter is a dimer whose ATPase activity and macrolide-binding capacity are regulated by the membrane fusion protein MacA. J Biol Chem. 2009 Jan 9;284(2):1145-54. doi: 10.1074/jbc.M806964200. Epub 2008, Oct 27. PMID:18955484 doi:http://dx.doi.org/10.1074/jbc.M806964200
- ↑ Zakharov SD, Sharma O, Zhalnina M, Yamashita E, Cramer WA. Pathways of colicin import: utilization of BtuB, OmpF porin and the TolC drug-export protein. Biochem Soc Trans. 2012 Dec 1;40(6):1463-8. doi: 10.1042/BST20120211. PMID:23176499 doi:http://dx.doi.org/10.1042/BST20120211
- ↑ Budiardjo SJ, Stevens JJ, Calkins AL, Ikujuni AP, Wimalasena VK, Firlar E, Case DA, Biteen JS, Kaelber JT, Slusky JSG. Colicin E1 opens its hinge to plug TolC. Elife. 2022 Feb 24;11. pii: 73297. doi: 10.7554/eLife.73297. PMID:35199644 doi:http://dx.doi.org/10.7554/eLife.73297
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