![]() Outten FW, Huffman DL, Hale JA, O’Halloran TV (2001) The independent cue and cus systems confer copper tolerance during aerobic and anaerobic growth in Escherichia coli. Outten FW, Outten CE, Hale J, O’Halloran TV (2000) Transcriptional activation of an Escherichia coli copper efflux regulon by the chromosomal MerR homologue. Orth P, Schnappinger D, Hillen W, Saenger W, Hinrichs W (2000) Structural basis of gene regulation by the tetracycline inducible Tet repressor-operator system. Nies DH (2003) Efflux-mediated heavy metal resistance in prokaryotes. Munson GP, Lam DL, Outten FW, O’Halloran TV (2000) Identification of a copper-responsive two-component system on the chromosome of Escherichia coli K-12. Maurer LM, Yohannes E, Bondurant SS, Radmacher M, Slonczewski JL (2005) pH regulates genes for flagellar motility, catabolism, and oxidative stress in Escherichia coli K-12. Kloosterman TG, van der Kooi-Pol MM, Bijlsma JJ, Kuipers OP (2007) The novel transcriptional regulator SczA mediates protection against Zn 2+ stress by activation of the Zn 2+-resistance gene czcD in Streptococcus pneumoniae. Harrison MD, Jones CE, Solioz M, Dameron CT (2000) Intracellular copper routing: the role of copper chaperones. Grass G, Thakali K, Klebba PE, Thieme D, Muller A, Wildner GF, Rensing C (2004) Linkage between catecholate siderophores and the multicopper oxidase CueO in Escherichia coli. J Bacteriol 187:2297–2307įranke S, Grass G, Rensing C, Nies DH (2003) Molecular analysis of the copper-transporting efflux system CusCFBA of Escherichia coli. Science 301:1383–1387Įgler M, Grosse C, Grass G, Nies DH (2005) Role of the extracytoplasmic function protein family sigma factor RpoE in metal resistance of Escherichia coli. Proc Natl Acad Sci USA 101:2404–2409Ĭhangela A, Chen K, Xue Y, Holschen J, Outten CE, O’Halloran TV, Mondragon A (2003) Molecular basis of metal-ion selectivity and zeptomolar sensitivity by CueR. Nat Protoc 4:1–13īrown CT, Callan CG Jr (2004) Evolutionary comparisons suggest many novel cAMP response protein binding sites in Escherichia coli. EMBO J 19:5071–5080īordoli L, Kiefer F, Arnold K, Benkert P, Battey J, Schwede T (2009) Protein structure homology modeling using SWISS-MODEL workspace. John, New Yorkīishop RE, Gibbons HS, Guina T, Trent MS, Miller SI, Raetz CR (2000) Transfer of palmitate from phospholipids to lipid A in outer membranes of gram-negative bacteria. The expression of ComC is controlled by ComR, a novel, TetR-like copper-responsive repressor.Īusubel RM, Brent R, Kingston RE, Moore DD, Smith JA, Struhl K (1995) Current protocols in molecular biology. Thus, ComC is an outer membrane protein which lowers the permeability of the outer membrane to copper. When grown in the presence of copper, ∆ comC cells had higher periplasmic and cytoplasmic copper levels, compared to the wild-type, as assessed by the activation of the periplasmic CusRS sensor and the cytoplasmic CueR sensor, respectively. By membrane fractionation, ComC was shown to be localized in the outer membrane. The purified ComR regulator bound to the promoter region of the comC gene in vitro and was released by copper. ComR did not regulate its own expression, but was required for copper-induction of the neighboring, divergently transcribed comC gene, as shown by real-time quantitative PCR and with a promoter- lux fusion. The mutant strain could be complemented by the comR gene on a plasmid, restoring luminescence to wild-type levels. One low-glower had a transposon insertion in the comR gene, which encodes a TetR-like transcriptional regulator. From a transposon-mutagenized library, strains were selected in which copper entry into cells was reduced, apparent as clones with reduced luminescence when grown in the presence of copper (low-glowers). In an attempt to shed light on this process, a lux-based biosensor was utilized to monitor intracellular copper levels in situ. The pathway of copper entry into Escherichia coli is still unknown. ![]()
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