title: Quorum-sensing systems LuxS/autoinducer 2 and Com regulate Streptococcus pneumoniae biofilms in a bioreactor with living cultures of human respiratory cells.
abstract: Streptococcus pneumoniae forms organized biofilms in the human upper respiratory tract that may play an essential role in both persistence and acute respiratory infection. However, the production and regulation of biofilms on human cells is not yet fully understood. In this work, we developed a bioreactor with living cultures of human respiratory epithelial cells (HREC) and a continuous flow of nutrients, mimicking the microenvironment of the human respiratory epithelium, to study the production and regulation of S. pneumoniae biofilms (SPB). SPB were also produced under static conditions on immobilized HREC. Our experiments demonstrated that the biomass of SPB increased significantly when grown on HREC compared to the amount on abiotic surfaces. Additionally, pneumococcal strains produced more early biofilms on lung cells than on pharyngeal cells. Utilizing the bioreactor or immobilized human cells, the production of early SPB was found to be regulated by two quorum-sensing systems, Com and LuxS/AI-2, since a mutation in either comC or luxS rendered the pneumococcus unable to produce early biofilms on HREC. Interestingly, while LuxS/autoinducer 2 (AI-2) regulated biofilms on both HREC and abiotic surfaces, Com control was specific for those structures produced on HREC. The biofilm phenotypes of strain D39-derivative ΔcomC and ΔluxS QS mutants were reversed by genetic complementation. Of note, SPB formed on immobilized HREC and incubated under static conditions were completely lysed 24 h postinoculation. Biofilm lysis was also regulated by the Com and LuxS/AI-2 quorum-sensing systems.
authors: Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia, USA. jvidalg@emory.edu
authors: Jorge E
authors: JE
authors: Vidal
authors: Kristen E
authors: KE
authors: Howery
authors: Herbert P
authors: HP
authors: Ludewick
authors: Porfirio
authors: P
authors: Nava
authors: Keith P
authors: KP
authors: Klugman
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms / Q000254:growth & development*; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology; D013437:Carbon-Sulfur Lyases / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D004847:Epithelial Cells / Q000382:microbiology*; D005816:Genetic Complementation Test; D006714:Homoserine / Q000031:analogs & derivatives* / Q000378:metabolism; D006801:Humans; D007783:Lactones / Q000378:metabolism*; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D053038:Quorum Sensing; D013296:Streptococcus pneumoniae / Q000235:genetics / Q000254:growth & development / Q000502:physiology*
chemical_list: D001426:Bacterial Proteins; D007783:Lactones; D050505:Mutant Proteins; C091088:N-octanoylhomoserine lactone; C423628:competence factor, Streptococcus; D006714:Homoserine; D013437:Carbon-Sulfur Lyases; C117753:LuxS protein, Bacteria
references: Trends Microbiol. 2013 Mar;21(3):129-35
references: 23273566
references: Diagn Microbiol Infect Dis. 2010 Aug;67(4):311-8
references: 20638597
references: Mol Microbiol. 2004 Nov;54(3):783-94
references: 15491367
references: Infect Immun. 2005 Feb;73(2):1129-40
references: 15664956
references: J Antimicrob Chemother. 2007 Feb;59(2):301-4
references: 17142818
references: Proc Natl Acad Sci U S A. 2010 Jan 26;107(4):1588-93
references: 20080633
references: Mol Microbiol. 2000 Jun;36(6):1279-92
references: 10931279
references: Infect Immun. 2005 Apr;73(4):1964-70
references: 15784536
references: Infect Immun. 2009 Sep;77(9):3722-30
references: 19564377
references: Environ Microbiol. 2013 Feb;15(2):502-16
references: 22913814
references: Proc Natl Acad Sci U S A. 1995 Nov 21;92(24):11140-4
references: 7479953
references: Infect Immun. 2003 Apr;71(4):1972-9
references: 12654815
references: Infect Immun. 2011 Oct;79(10):4050-60
references: 21825061
references: Antimicrob Agents Chemother. 2009 Oct;53(10):4258-63
references: 19596873
references: J Bacteriol. 2001 Feb;183(3):897-908
references: 11208787
references: Infect Immun. 2005 Feb;73(2):1034-43
references: 15664947
references: JAMA. 2006 Jul 12;296(2):202-11
references: 16835426
references: FEMS Microbiol Lett. 2006 Jan;254(1):1-11
references: 16451172
references: Science. 2001 Jul 20;293(5529):498-506
references: 11463916
references: Laryngoscope. 2006 Jul;116(7):1121-6
references: 16826045
references: Nat Rev Microbiol. 2008 Apr;6(4):288-301
references: 18340341
references: Infect Immun. 1992 May;60(5):1740-6
references: 1563759
references: Mol Microbiol. 2006 Jun;60(6):1446-56
references: 16796680
references: PLoS One. 2011;6(5):e19844
references: 21611130
references: Microbes Infect. 2009 Feb;11(2):281-7
references: 19114123
references: Proc Natl Acad Sci U S A. 2002 May 28;99(11):7681-6
references: 12032343
references: PLoS Pathog. 2010 Aug 12;6(8):e1001044
references: 20714350
references: Cell Microbiol. 2008 Oct;10(10):1975-86
references: 18547338
references: Infect Immun. 2012 Aug;80(8):2744-60
references: 22645283
references: Lancet. 2009 Oct 31;374(9700):1543-56
references: 19880020
references: BMC Microbiol. 2011 Apr 14;11:75
references: 21492426
references: Infect Immun. 2004 May;72(5):2964-75
references: 15102809
references: Mol Microbiol. 2004 Feb;51(4):1051-70
references: 14763980
references: J Bacteriol. 2006 Nov;188(22):7785-95
references: 16936041
references: J Bacteriol. 2003 Aug;185(16):4851-60
references: 12897005
references: Infect Immun. 2011 Nov;79(11):4550-8
references: 21875962
references: Cell. 1994 Feb 25;76(4):717-24
references: 8124710
references: Proc Natl Acad Sci U S A. 2005 Jun 14;102(24):8710-5
references: 15928084
references: EMBO J. 1998 May 15;17(10):2894-903
references: 9582283
references: FEMS Microbiol Lett. 2007 Mar;268(2):217-24
references: 17328748
references: J Exp Med. 1944 Feb 1;79(2):137-58
references: 19871359
references: J Bacteriol. 2003 Dec;185(24):7176-83
references: 14645278
references: J Bacteriol. 2007 Jan;189(1):38-51
references: 17041037
references: Appl Environ Microbiol. 2012 Aug;78(16):5897-905
references: 22706053
references: J Infect Dis. 2010 Oct 1;202(7):1068-75
references: 20715928
references: Nature. 2000 Oct 12;407(6805):762-4
references: 11048725
references: J Mol Biol. 1984 Sep 5;178(1):91-104
references: 6548265
references: Mol Microbiol. 1996 Aug;21(4):853-62
references: 8878046
references: J Exp Med. 2009 Aug 31;206(9):1845-52
references: 19687228
references: PLoS One. 2011;6(12):e28738
references: 22174882
references: Mol Microbiol. 2001 Jan;39(1):126-35
references: 11123694
references: Mol Microbiol. 2006 Sep;61(5):1196-210
references: 16925554
references: Infect Immun. 2005 May;73(5):2680-9
references: 15845469
references: Clin Infect Dis. 2008 Dec 1;47 Suppl 3:S202-6
references: 18986290
references: FEMS Microbiol Rev. 2009 May;33(3):627-42
references: 19396959
references: Microb Biotechnol. 2012 Jul;5(4):455-65
references: 21906265
references: Plasmid. 2003 May;49(3):281-5
references: 12749839
references: Microbiol Mol Biol Rev. 2001 Jun;65(2):187-207 ; first page, table of contents
references: 11381099
references: Mol Microbiol. 2001 May;40(3):555-71
references: 11359563
references: Cell Microbiol. 2009 Sep;11(9):1306-28
references: 19438515
references: Appl Environ Microbiol. 2004 Aug;70(8):4980-8
references: 15294838
references: Int Microbiol. 2009 Jun;12(2):77-85
references: 19784927