title: Copper efflux is induced during anaerobic amino acid limitation in Escherichia coli to protect iron-sulfur cluster enzymes and biogenesis.
abstract: Adaptation to changing environments is essential to bacterial physiology. Here we report a unique role of the copper homeostasis system in adapting Escherichia coli to its host-relevant environment of anaerobiosis coupled with amino acid limitation. We found that expression of the copper/silver efflux pump CusCFBA was significantly upregulated during anaerobic amino acid limitation in E. coli without the supplement of exogenous copper. Inductively coupled plasma mass spectrometry analysis of the total intracellular copper content combined with transcriptional assay of the P(cusC)-lacZ reporter in the presence of specific Cu(I) chelators indicated that anaerobic amino acid limitation led to the accumulation of free Cu(I) in the periplasmic space of E. coli, resulting in Cu(I) toxicity. Cells lacking cusCFBA and another copper transporter, copA, under this condition displayed growth defects and reduced ATP production during fumarate respiration. Ectopic expression of the Fe-S cluster enzyme fumarate reductase (Frd), or supplementation with amino acids whose biosynthesis involves Fe-S cluster enzymes, rescued the poor growth of ΔcusC cells. Yet, Cu(I) treatment did not impair the Frd activity in vitro. Further studies revealed that the alternative Fe-S cluster biogenesis system Suf was induced during the anaerobic amino acid limitation, and ΔcusC enhanced this upregulation, indicating the impairment of the Fe-S cluster assembly machinery and the increased Fe-S cluster demands under this condition. Taken together, we conclude that the copper efflux system CusCFBA is induced during anaerobic amino acid limitation to protect Fe-S cluster enzymes and biogenesis from the endogenously originated Cu(I) toxicity, thus facilitating the physiological adaptation of E. coli.
authors.affiliation: School of Biological Sciences, The University of Hong Kong, Hong Kong SAR.
authors.forename: Danny Ka Chun
authors.initials: DK
authors.lastname: Fung
authors.forename: Wai Yin
authors.initials: WY
authors.lastname: Lau
authors.forename: Wing Tat
authors.initials: WT
authors.lastname: Chan
authors.forename: Aixin
authors.initials: A
authors.lastname: Yan
mesh_terms: D000222:Adaptation, Physiological; D000596:Amino Acids / Q000378:metabolism*; D000693:Anaerobiosis; D001692:Biological Transport; D003300:Copper / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D007506:Iron-Sulfur Proteins / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D029968:Escherichia coli Proteins; D007506:Iron-Sulfur Proteins; D003300:Copper
references.citation: J Bacteriol. 1974 Jan;117(1):232-41
references.pmid: 4587605
references.citation: J Bacteriol. 2008 Aug;190(15):5431-8
references.pmid: 18539744
references.citation: J Bacteriol. 2001 Oct;183(20):5803-12
references.pmid: 11566977
references.citation: Microbiology (Reading). 2012 Jun;158(Pt 6):1402-1413
references.pmid: 22493300
references.citation: J Biol Chem. 2001 Aug 17;276(33):30670-7
references.pmid: 11399769
references.citation: Arch Biochem Biophys. 2000 Aug 15;380(2):267-73
references.pmid: 10933881
references.citation: J Bacteriol. 2003 Jul;185(13):3804-12
references.pmid: 12813074
references.citation: Mol Microbiol. 2013 Feb;87(3):466-77
references.pmid: 23171030
references.citation: Physiol Rev. 2007 Jul;87(3):1011-46
references.pmid: 17615395
references.citation: Nat Rev Microbiol. 2006 Sep;4(9):705-9
references.pmid: 16894339
references.citation: Future Microbiol. 2010 Apr;5(4):603-21
references.pmid: 20353301
references.citation: J Biol Chem. 1995 Aug 25;270(34):19767-77
references.pmid: 7649986
references.citation: Curr Opin Microbiol. 2012 Feb;15(1):3-9
references.pmid: 22204808
references.citation: PLoS Biol. 2006 Jan;4(1):e23
references.pmid: 16535775
references.citation: Curr Protoc Mol Biol. 2007 Jul;Chapter 1:Unit 1.17
references.pmid: 18265391
references.citation: Adv Appl Microbiol. 2008;65:217-47
references.pmid: 19026867
references.citation: Science. 2003 May 9;300(5621):931-6
references.pmid: 12738850
references.citation: Nature. 2011 Feb 24;470(7335):558-62
references.pmid: 21350490
references.citation: Mol Microbiol. 2006 Aug;61(3):645-54
references.pmid: 16803591
references.citation: J Appl Microbiol. 2006 Apr;100(4):623-32
references.pmid: 16553716
references.citation: Biochim Biophys Acta. 2009 May;1794(5):834-43
references.pmid: 19230852
references.citation: Free Radic Biol Med. 1996;21(1):117-21
references.pmid: 8791100
references.citation: Nat Chem Biol. 2009 Aug;5(8):593-9
references.pmid: 19561621
references.citation: J Bacteriol. 2000 Oct;182(20):5864-71
references.pmid: 11004187
references.citation: Proc Natl Acad Sci U S A. 2000 Jan 18;97(2):652-6
references.pmid: 10639134
references.citation: Mycologia. 1971 Nov-Dec;63(6):1231-4
references.pmid: 5156995
references.citation: Drugs. 2009 Aug 20;69(12):1555-623
references.pmid: 19678712
references.citation: IUBMB Life. 2008 Sep;60(9):569-74
references.pmid: 18481812
references.citation: J Biol Chem. 2000 Oct 6;275(40):31024-9
references.pmid: 10915804
references.citation: Nat Rev Microbiol. 2006 Aug;4(8):629-36
references.pmid: 16845433
references.citation: Proc Natl Acad Sci U S A. 2009 May 19;106(20):8344-9
references.pmid: 19416816
references.citation: Mol Microbiol. 2013 Feb;87(3):447-54
references.pmid: 23217080
references.citation: FEMS Microbiol Lett. 2012 May;330(1):30-7
references.pmid: 22348296
references.citation: Nat Rev Microbiol. 2010 Apr;8(4):251-9
references.pmid: 20190823
references.citation: J Antimicrob Chemother. 2005 Jul;56(1):20-51
references.pmid: 15914491
references.citation: J Bacteriol. 2010 May;192(10):2512-24
references.pmid: 20233928
references.citation: Science. 2003 Sep 5;301(5638):1383-7
references.pmid: 12958362
references.citation: Mol Microbiol. 2009 Jul;73(2):212-25
references.pmid: 19538445
references.citation: Proc Natl Acad Sci U S A. 2000 Jun 6;97(12):6640-5
references.pmid: 10829079
references.citation: Curr Opin Chem Biol. 2008 Apr;12(2):214-21
references.pmid: 18258210
references.citation: J Bacteriol. 2011 May;193(10):2381-7
references.pmid: 21398536
references.citation: FEMS Microbiol Rev. 2009 Mar;33(2):430-49
references.pmid: 19207745
references.citation: Nat Med. 1999 Feb;5(2):183-8
references.pmid: 9930866
references.citation: Science. 2001 Jun 29;292(5526):2488-92
references.pmid: 11397910
references.citation: Nat Rev Microbiol. 2010 Jun;8(6):436-46
references.pmid: 20467446
references.citation: Annu Rev Microbiol. 1995;49:145-74
references.pmid: 8561457
references.citation: Nat Struct Biol. 2000 Oct;7(10):910-7
references.pmid: 11017202
references.citation: Mol Microbiol. 2010 Dec;78(6):1448-67
references.pmid: 21143317
references.citation: Proc Natl Acad Sci U S A. 2011 Jan 25;108(4):1621-6
references.pmid: 21205886
references.citation: Biochim Biophys Acta. 1974 Oct 18;368(1):125-9
references.pmid: 4370728
references.citation: J Bacteriol. 2007 Mar;189(5):1616-26
references.pmid: 17189367
references.citation: Biochem Biophys Res Commun. 2001 Sep 7;286(5):902-8
references.pmid: 11527384
references.citation: Biochim Biophys Acta. 2002 Jan 17;1553(1-2):140-57
references.pmid: 11803023
references.citation: Metallomics. 2011 Nov;3(11):1109-18
references.pmid: 21984219
references.citation: J Biol Chem. 2011 Jul 29;286(30):26576-84
references.pmid: 21642439