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The Imp/OstA Family [Function: Biogenesis/Secretion] Seed alignment | Full alignment in OMPdb | |
In Gram-negative bacteria, the components of the outer membrane are synthesized in the cytoplasm or the inner membrane and must therefore traverse the inner membrane and the periplasm on the way to their final destination. Lipopolysaccharide molecules (LPS) are an essential component of the bacterial outer membrane and consist of a hydrophobic membrane anchor (lipid A) and an oligosaccharide core region that can be extended in some bacteria by a repeating oligosaccharide, the O-antigen. An outer membrane protein, which probably forms a ß-barrel, is required for the appearance of LPS at the bacterial cell surface. This protein is known as Imp (increased membrane permeability) or OstA (organic solvent tolerance) because Escherichia coli strains expressing mutant versions of this protein showed altered membrane permeability. Recent structures from LptD protein suggest a ß-barrel domain with 26 segments. | |
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Literature references | |
Imp/OstA is required for cell envelope biogenesis in Escherichia coli Mol Microbiol. 2002 Sep;45(5):1289-302. doi: 10.1046/j.1365-2958.2002.03091.x. PMID: 12207697 | |
Biogenesis of the Gram-negative bacterial outer membrane Curr Opin Microbiol. 2004 Dec;7(6):610-6. doi: 10.1016/j.mib.2004.10.011. PMID: 15556033 | |
Biogenesis of the Gram-negative bacterial outer membrane Curr Opin Microbiol. 2004 Dec;7(6):610-6. doi: 10.1016/j.mib.2004.10.011. PMID: 15556033 | |
Proteins in this family with 3D-structure | |
Q8ZRW0 | |
Q83SQ0 | |
P31554 | |
Q9I5U2 | |
Q8ZIK3 | |
C4T9I0 |
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