Elevated exopolysaccharide levels in Pseudomonas aeruginosa flagellar mutants have implications for biofilm growth and chronic infections

Autoři: Joe J. Harrison aff001;  Henrik Almblad aff001;  Yasuhiko Irie aff002;  Daniel J. Wolter aff002;  Heather C. Eggleston aff004;  Trevor E. Randall aff001;  Jacob O. Kitzman aff005;  Bethany Stackhouse aff005;  Julia C. Emerson aff006;  Sharon Mcnamara aff006;  Tyler J. Larsen aff002;  Jay Shendure aff005;  Lucas R. Hoffman aff002;  Daniel J. Wozniak aff004;  Matthew R. Parsek aff002
Působiště autorů: Department of Biological Sciences, University of Calgary, University Drive NW, Calgary, AB, Canada aff001;  Department of Microbiology, University of Washington, Seattle, Washington, United states of America aff002;  Department of Pediatrics, University of Washington, Seattle, Washington, United States of America aff003;  Department of Microbial Infection and Immunity, Department of Microbiology, Center for Microbial Interface Biology, The Ohio State University, Columbus, Ohio, United States of America aff004;  Department of Genome Sciences, University of Washington, Seattle, Washington, United States of America aff005;  Center for Clinical and Translational Research, Seattle Children’s Hospital, Seattle, Washington, United States of America aff006
Vyšlo v časopise: Elevated exopolysaccharide levels in Pseudomonas aeruginosa flagellar mutants have implications for biofilm growth and chronic infections. PLoS Genet 16(6): e32767. doi:10.1371/journal.pgen.1008848
Kategorie: Research Article
doi: https://doi.org/10.1371/journal.pgen.1008848


Pseudomonas aeruginosa colonizes the airways of cystic fibrosis (CF) patients, causing infections that can last for decades. During the course of these infections, P. aeruginosa undergoes a number of genetic adaptations. One such adaptation is the loss of swimming motility functions. Another involves the formation of the rugose small colony variant (RSCV) phenotype, which is characterized by overproduction of the exopolysaccharides Pel and Psl. Here, we provide evidence that the two adaptations are linked. Using random transposon mutagenesis, we discovered that flagellar mutations are linked to the RSCV phenotype. We found that flagellar mutants overexpressed Pel and Psl in a surface-contact dependent manner. Genetic analyses revealed that flagellar mutants were selected for at high frequencies in biofilms, and that Pel and Psl expression provided the primary fitness benefit in this environment. Suppressor mutagenesis of flagellar RSCVs indicated that Psl overexpression required the mot genes, suggesting that the flagellum stator proteins function in a surface-dependent regulatory pathway for exopolysaccharide biosynthesis. Finally, we identified flagellar mutant RSCVs among CF isolates. The CF environment has long been known to select for flagellar mutants, with the classic interpretation being that the fitness benefit gained relates to an impairment of the host immune system to target a bacterium lacking a flagellum. Our new findings lead us to propose that exopolysaccharide production is a key gain-of-function phenotype that offers a new way to interpret the fitness benefits of these mutations.

Klíčová slova:

Bacterial biofilms – Biofilms – Cystic fibrosis – Deletion mutation – Exopolysaccharides – Flagella – Phenotypes – Pseudomonas aeruginosa


1. Razvi S, Quittell L, Sewall A, Quinton H, Marshall B, Saiman L. Respiratory microbiology of patients with cystic fibrosis in the United States, 1995–2005. Chest. 2009;136:1554–60. doi: 10.1378/chest.09-0132 19505987

2. Smith EE, Buckley DG, Wu Z, Saenphimmachak C, Hoffman LR, D'Argenio DA, et al. Genetic adaptation by Pseudomonas aeruginosa to the airways of cystic fibrosis patients. Proc Natl Acad Sci U S A. 2006;103:8487–92. doi: 10.1073/pnas.0602138103 16687478

3. Folkesson A, Jelsbak L, Yang L, Johansen HK, Ciofu O, Hoiby N, et al. Adaptation of Pseudomonas aeruginosa to the cystic fibrosis airway: an evolutionary perspective. Nat Rev Microbiol. 2012;10(12):841–51. doi: 10.1038/nrmicro2907 23147702

4. Marvig RL, Sommer LM, Molin S, Johansen HK. Convergent evolution and adaptation of Pseudomonas aeruginosa within patients with cystic fibrosis. Nat Genet. 2015;47(1):57–64. doi: 10.1038/ng.3148 25401299

5. Doggett RG, Harrison GM, Wallis ES. Comparision of some properties of Pseudomonas aeruginosa isolated from infections in persons with and without cysitc fibrosis. J Bacteriol. 1964;87(2):427–31.

6. Taylor RF, Hodson ME, Pitt TL. Auxotrophy of Pseudomonas aeruginosa in cystic fibrosis. FEMS Microbiol Lett. 1992;71(3):243–6. doi: 10.1016/0378-1097(92)90716-2 1624122

7. Hancock RE, Mutharia LM, Chan L, Darveau RP, Speert DP, Pier GB. Pseudomonas aeruginosa isolates from patients with cystic fibrosis: a class of serum-sensitive, nontypable strains deficient in lipopolysaccharide O side chains. Infect Immun. 1983;42(1):170–7. 6413410

8. Luzar MA, Thomassen MJ, Montie TC. Flagella and motility alterations in Pseudomonas aeruginosa strains from patients with cystic fibrosis: relationship to patient clinical condition. Infect Immun. 1985;50:577–82. 3932214

9. Worlitzsch D, Tarran R, Ulrich M, Schwab U, Cekici A, Meyer KC, et al. Effects of reduced mucus oxygen concentration in airway Pseudomonas infections of cystic fibrosis patients. J Clin Invest. 2002;109(3):317–25. doi: 10.1172/JCI13870 11827991

10. Singh PK, Schaefer AL, Parsek MR, Moninger TO, Welsh MJ, Greenberg EP. Quorum-sensing signals indicate that cystic fibrosis lungs are infected with bacterial biofilms. Nature. 2000;407(6805):762–4. doi: 10.1038/35037627 11048725

11. Boles BR, Theondel M, Singh PK. Self-generated diversity produces "insurance effects" in biofilm communities. Proc Natl Acad Sci U S A. 2004;101:16630–5. doi: 10.1073/pnas.0407460101 15546998

12. Kirisitis MJ, Prost L, Starkey M, Parsek M. Characterization of colony morphology variants isolated from Pseudomonas aeruginosa biofilms. Appl Environ Microbiol. 2005;71:4809–21. doi: 10.1128/AEM.71.8.4809-4821.2005 16085879

13. Häussler S. Biofilm formation by the small colony variant phenotype of Pseudomonas aeruginosa. Environ Microbiol. 2004;6:546–51. doi: 10.1111/j.1462-2920.2004.00618.x 15142242

14. Haussler S, Ziegler I, Lottel A, von Gotz F, Rohde M, Wehmhohner D, et al. Highly adherent small-colony variants of Pseudomonas aeruginosa in cystic fibrosis lung infection. J Med Microbiol. 2003;52(Pt 4):295–301. doi: 10.1099/jmm.0.05069-0 12676867

15. Malone JG. Role of small colony variants in persistence of Pseudomonas aeruginosa infections in cystic fibrosis lungs. Infection and Drug Resistance. 2015;8:237–47. doi: 10.2147/IDR.S68214 26251621

16. Starkey M, Hickman J, Ma L, Zhang N, De Long S, Hinz A, et al. Pseudomonas aeruginosa rugose small colony variants have adaptations that likely promote persistence in the cystic fibrosis lung. J Bacteriol. 2009;191(11):3492–503. doi: 10.1128/JB.00119-09 19329647

17. Borlee BR, Goldman AD, Murakami K, Samudrala R, Wozniak DJ, Parsek MR. Pseudomonas aeruginosa uses a cyclic-di-GMP-regulated adhesin to reinforce the biofilm extracellular matrix. Mol Microbiol. 2010;75(4):827–42. doi: 10.1111/j.1365-2958.2009.06991.x 20088866

18. Colvin KM, Gordon VD, Murakami K, Borlee BR, Wozniak DJ, Wong GC, et al. The Pel polysaccharide can serve a structural and protective role in the biofilm matrix of Pseudomonas aeruginosa. PLoS Pathog. 2011;7(1):e1001264. doi: 10.1371/journal.ppat.1001264 21298031

19. Billings N, Millan M, Caldara M, Rusconi R, Tarasova Y, Stocker R, et al. The extracellular matrix Component Psl provides fast-acting antibiotic defense in Pseudomonas aeruginosa biofilms. PLoS Pathog. 2013;9(8):e1003526. doi: 10.1371/journal.ppat.1003526 23950711

20. Mishra M, Byrd MS, Sergeant S, Azad AK, Parsek MR, McPhail L, et al. Pseudomonas aeruginosa Psl polysaccharide reduces neutrophil phagocytosis and the oxidative response by limiting complement-mediated opsonization. Cell Microbiol. 2012;14(1):95–106. doi: 10.1111/j.1462-5822.2011.01704.x 21951860

21. Irie Y, Starkey M, Edwards AN, Wozniak DJ, Romeo T, Parsek MR. Pseudomonas aeruginosa biofilm matrix polysaccharide Psl is regulated transcriptionally by RpoS and post-transcriptionally by RsmA. Mol Microbiol. 2010;78(1):158–72. doi: 10.1111/j.1365-2958.2010.07320.x 20735777

22. Tseng BS, Zhang W, Harrison JJ, Quach TP, Song JL, Penterman J, et al. The extracellular matrix protects Pseudomonas aeruginosa biofilms by limiting the penetration of tobramycin. Environ Microbiol. 2013;15(10):2865–78. doi: 10.1111/1462-2920.12155 23751003

23. Harrison JJ, Turner RJ, Ceri H. Persister cells, the biofilm matrix and tolerance to metal cations in biofilm and planktonic Pseudomonas aeruginosa. Environ Microbiol. 2005;7(7):981–94. doi: 10.1111/j.1462-2920.2005.00777.x 15946294

24. Lebeaux D, Ghigo JM, Beloin C. Biofilm-related infections: bridging the gap between clinical management and fundamental aspects of recalcitrance toward antibiotics. Microbiol Mol Biol Rev. 2014;78(3):510–43. doi: 10.1128/MMBR.00013-14 25184564

25. Alhede M, Kragh KN, Qvortrup K, Allesen-Holm M, van Gennip M, Christensen LD, et al. Phenotypes of non-attached Pseudomonas aeruginosa aggregates resemble surface attached biofilm. PLoS One. 2011;6(11):e27943. doi: 10.1371/journal.pone.0027943 22132176

26. Haussler S, Tummler B, Weissbrodt H, Rohde M, Steinmetz I. Small-colony variants of Pseudomonas aeruginosa in cystic fibrosis. Clin Infect Dis. 1999;29(3):621–5. doi: 10.1086/598644 10530458

27. Schneider M, Muhlemann K, Droz S, Couzinet S, Casaulta C, Zimmerli S. Clinical characteristics associated with isolation of small-colony variants of Staphylococcus aureus and Pseudomonas aeruginosa from respiratory secretions of patients with cystic fibrosis. J Clin Microbiol. 2008;46(5):1832–4. doi: 10.1128/JCM.00361-08 18322058

28. Malone JG, Jaeger T, Spangler C, Ritz D, Spang A, Arrieumerlou C, et al. YfiBNR mediates cyclic-di-GMP dependent small colony variant formation and persistence in Pseudomonas aeruginosa. PLoS Pathog. 2010;6(3):e1000804.

29. Hickman JW, Tifrea DF, Harwood CS. A chemosensory system that regulates biofilm formation through modulation of cyclic diguanylate levels. Proc Natl Acad Sci U S A. 2005;102(40):14422–7. doi: 10.1073/pnas.0507170102 16186483

30. Drenkard E, Ausubel FM. Pseudomonas biofilm formation and antibiotic resistance are linked to phenotypic variation. Nature. 2002;416(6882):740–3. doi: 10.1038/416740a 11961556

31. Hengge R. Principles of c-di-GMP signalling in bacteria. Nat Rev Microbiol. 2009;7:263–73. doi: 10.1038/nrmicro2109 19287449

32. D'Argenio DA, Calfee MW, Rainey PB, Pesci EC. Autolysis and autoaggregation in Pseudomonas aeruginosa colony morphology mutants. J Bacteriol. 2002;184(23):6481–9. doi: 10.1128/jb.184.23.6481-6489.2002 12426335

33. Ueda A, Wood TK. Connecting quorum sensing, c-di-GMP, pel polysaccharide, and biofilm formation in Pseudomonas aeruginosa through tyrosine phosphatase TpbA (PA3885). PLoS Pathog. 2009;5(6):e1000483. doi: 10.1371/journal.ppat.1000483 19543378

34. Giddens SR, Jackson RW, Moon CD, Jacobs MA, Zhang XX, Gehrig SM, et al. Mutational activation of niche-specific genes provides insight into regulatory networks and bacterial function in a complex environment. Proc Natl Acad Sci U S A. 2007;104(46):18247–52. doi: 10.1073/pnas.0706739104 17989226

35. Jones CJ, Newsom D, Kelly B, Irie Y, Jennings LK, Xu B, et al. ChIP-Seq and RNA-Seq reveal an AmrZ-mediated mechanism for cyclic di-GMP synthesis and biofilm development by Pseudomonas aeruginosa. PLoS Pathog. 2014;10(3):e1003984. doi: 10.1371/journal.ppat.1003984 24603766

36. Cabeen MT, Leiman SA, Losick R. Colony-morphology screening uncovers a role for the Pseudomonas aeruginosa nitrogen-related phosphotransferase system in biofilm formation. Mol Microbiol. 2016;99(3):557–70. doi: 10.1111/mmi.13250 26483285

37. Malone JG, Jaeger T, Manfredi P, Dotsch A, Blanka A, Bos R, et al. The YfiBNR signal transduction mechanism reveals novel targets for the evolution of persistent Pseudomonas aeruginosa in cystic fibrosis airways. PLoS Pathog. 2012;8(6):e1002760. doi: 10.1371/journal.ppat.1002760 22719254

38. Moscoso JA, Mikkelsen H, Heeb S, Williams P, Filloux A. The Pseudomonas aeruginosa sensor RetS switches type III and type VI secretion via c-di-GMP signalling. Environ Microbiol. 2011;13(12):3128–38. doi: 10.1111/j.1462-2920.2011.02595.x 21955777

39. Blanka A, Duvel J, Dotsch A, Klinkert B, Abraham WR, Kaever V, et al. Constitutive production of c-di-GMP is associated with mutations in a variant of Pseudomonas aeruginosa with altered membrane composition. Science Signaling. 2015;8(372):ra36. doi: 10.1126/scisignal.2005943 25872871

40. Wolter DJ, Emerson JC, McNamara S, Buccat AM, Qin X, Cochrane E, et al. Staphylococcus aureus small-colony variants are independently associated with worse lung disease in children with cystic fibrosis. Clin Infect Dis. 2013;57(3):384–91. doi: 10.1093/cid/cit270 23625938

41. Li Z, Kosorok MR, Farrell PM, Laxova A, West SE, Green CG, et al. Longitudinal development of mucoid Pseudomonas aeruginosa infection and lung disease progression in children with cystic fibrosis. JAMA. 2005;293(5):581–8. doi: 10.1001/jama.293.5.581 15687313

42. Siehnel R, Traxler B, An DD, Parsek MR, Schaefer AL, Singh PK. A unique regulator controls the activation threshold of quorum-regulated genes in Pseudomonas aeruginosa. Proc Natl Acad Sci U S A. 2010;107(17):7916–21. doi: 10.1073/pnas.0908511107 20378835

43. Cohen D, Mechold U, Nevenzal H, Yarmiyhu Y, Randall TE, Bay DC, et al. Oligoribonuclease is a central feature of cyclic diguanylate signaling in Pseudomonas aeruginosa. Proc Natl Acad Sci U S A. 2015;112(36):11359–64. doi: 10.1073/pnas.1421450112 26305928

44. Orr MW, Donaldson GP, Severin GB, Wang J, Sintim HO, Waters CM, et al. Oligoribonuclease is the primary degradative enzyme for pGpG in Pseudomonas aeruginosa that is required for cyclic-di-GMP turnover. Proc Natl Acad Sci U S A. 2015;112(36):E5048–57. doi: 10.1073/pnas.1507245112 26305945

45. Dasgupta N, Wolfgang MC, Goodman AL, Arora SK, Jyot J, Lory S, et al. A four-tiered transcriptional regulatory circuit controls flagellar biogenesis in Pseudomonas aeruginosa. Mol Microbiol. 2003;50(3):809–24. doi: 10.1046/j.1365-2958.2003.03740.x 14617143

46. Wu DC, Zamorano-Sánchez D, Pagliai FA, Park JH, Floyd KA, Lee CK, et al. Reciprocal c-di-GMP signaling: Incomplete flagellum biogenesis triggers c-di-GMP signaling pathways that promote biofilm formation. PLoS Genet. 2020;16(3):e1008703. doi: 10.1371/journal.pgen.1008703 32176702

47. Watnick PI, Lauriano CM, Klose KE, Croal L, Kolter R. The absence of a flagellum leads to altered colony morphology, biofilm development and virulence in Vibrio cholerae O139. Mol Microbiol. 2001;39(2):223–35. doi: 10.1046/j.1365-2958.2001.02195.x 11136445

48. Belas R. Biofilms, flagella, and mechanosensing of surfaces by bacteria. Trends Microbiol. 2014;22(9):517–27. doi: 10.1016/j.tim.2014.05.002 24894628

49. Kawagishi I, Imagawa M, Imae Y, McCarter L, Homma M. The sodium-driven polar flagellar motor of marine Vibrio as the mechanosensor that regulates lateral flagellar expression. Mol Microbiol. 1996;20(4):693–9. doi: 10.1111/j.1365-2958.1996.tb02509.x 8793868

50. McCarter L, Hilmen M, Silverman M. Flagellar dynamometer controls swarmer cell differentiation of V. parahaemolyticus. Cell. 1988;54(3):345–51. doi: 10.1016/0092-8674(88)90197-3 3396074

51. Hug I, Deshpande S, Sprecher KS, Pfohl T, Jenal U. Second messenger-mediated tactile response by a bacterial rotary motor. Science. 2017;358(6362):531–4. doi: 10.1126/science.aan5353 29074777

52. Belas R, Suvanasuthi R. The ability of Proteus mirabilis to sense surfaces and regulate virulence gene expression involves FliL, a flagellar basal body protein. J Bacteriol. 2005;187(19):6789–803. doi: 10.1128/JB.187.19.6789-6803.2005 16166542

53. Cairns LS, Marlow VL, Bissett E, Ostrowski A, Stanley-Wall NR. A mechanical signal transmitted by the flagellum controls signalling in Bacillus subtilis. Mol Microbiol. 2013;90(1):6–21. doi: 10.1111/mmi.12342 23888912

54. Doyle TB, Hawkins AC, McCarter LL. The complex flagellar torque generator of Pseudomonas aeruginosa. J Bacteriol. 2004;186(19):6341–50. doi: 10.1128/JB.186.19.6341-6350.2004 15375113

55. Toutain CM, Zegans ME, O'Toole GA. Evidence for two flagellar stators and their role in the motility of Pseudomonas aeruginosa. J Bacteriol. 2005;187(2):771–7. doi: 10.1128/JB.187.2.771-777.2005 15629949

56. Kuchma SL, Brothers KM, Merritt JH, Liberati NT, Ausubel FM, O'Toole GA. BifA, a cyclic-Di-GMP phosphodiesterase, inversely regulates biofilm formation and swarming motility by Pseudomonas aeruginosa PA14. J Bacteriol. 2007;189(22):8165–78. doi: 10.1128/JB.00586-07 17586641

57. Caiazza NC, O'Toole GA. SadB is required for the transition from reversible to irreversible attachment during biofilm formation by Pseudomonas aeruginosa PA14. J Bacteriol. 2004;186(14):4476–85. doi: 10.1128/JB.186.14.4476-4485.2004 15231779

58. Caiazza NC, Merritt JH, Brothers KM, O'Toole GA. Inverse regulation of biofilm formation and swarming motility by Pseudomonas aeruginosa PA14. J Bacteriol. 2007;189(9):3603–12. doi: 10.1128/JB.01685-06 17337585

59. Baker AE, Webster SS, Diepold A, Kuchma SL, Bordeleau E, Armitage JP, et al. Flagellar stators stimulate c-di-GMP production by Pseudomonas aeruginosa. J Bacteriol. 2019:JB.00741–18.

60. Siryaporn A, Kuchma SL, O’Toole GA, Gitai Z. Surface attachment induces Pseudomonas aeruginosa virulence. Proc Natl Acad Sci U S A. 2014;111(47):16860–5. doi: 10.1073/pnas.1415712111 25385640

61. Luo Y, Zhao K, Baker AE, Kuchma SL, Coggan KA, Wolfgang MC, et al. A hierarchical cascade of second messengers regulates Pseudomonas aeruginosa surface behaviors. mBio. 2015;6(1):e02456–14. doi: 10.1128/mBio.02456-14 25626906

62. Lauriano CM, Ghosh C, Correa NE, Klose KE. The sodium-driven flagellar motor controls exopolysaccharide expression in Vibrio cholerae. J Bacteriol. 2004;186(15):4864–74. doi: 10.1128/JB.186.15.4864-4874.2004 15262923

63. Klausen M, Heydorn A, Ragas P, Lambertsen L, Aaes-Jorgensen A, Molin S, et al. Biofilm formation by Pseudomonas aeruginosa wild type, flagella and type IV pili mutants. Mol Microbiol. 2003;48(6):1511–24. doi: 10.1046/j.1365-2958.2003.03525.x 12791135

64. Barken KB, Pamp SJ, Yang L, Gjermansen M, Bertrand JJ, Klausen M, et al. Roles of type IV pili, flagellum-mediated motility and extracellular DNA in the formation of mature multicellular structures in Pseudomonas aeruginosa biofilms. Environ Microbiol. 2008;10(9):2331–43. doi: 10.1111/j.1462-2920.2008.01658.x 18485000

65. Nadell CD, Bassler BL. A fitness trade-off between local competition and dispersal in Vibrio cholerae biofilms. Proc Natl Acad Sci U S A. 2011;108(34):14181–5. doi: 10.1073/pnas.1111147108 21825170

66. Schluter J, Nadell CD, Bassler BL, Foster KR. Adhesion as a weapon in microbial competition. The ISME Journal. 2015;9(1):139–49. doi: 10.1038/ismej.2014.174 25290505

67. Xavier JB, Foster KR. Cooperation and conflict in microbial biofilms. Proc Natl Acad Sci U S A. 2007;104(3):876–81. doi: 10.1073/pnas.0607651104 17210916

68. Mahenthiralingam E, Campbell ME, Speert DP. Nonmotility and phagocytic resistance of Pseudomonas aeruginosa from chronically colonized patients with cystic fibrosis. Infect Immun. 1994;62:596–605. 8300217

69. Jorth P, Staudinger BJ, Wu X, Hisert KB, Hayden H, Garudathri J, et al. Regional isolation drives bacterial diversification within cystic fibrosis lungs. Cell Host Microbe. 2015;18(3):307–19. doi: 10.1016/j.chom.2015.07.006 26299432

70. Lovewell RR, Collins RM, Acker JL, O'Toole GA, Wargo MJ, Berwin B. Step-wise loss of bacterial flagellar torsion confers progressive phagocytic evasion. PLoS Pathog. 2011;7(9):e1002253. doi: 10.1371/journal.ppat.1002253 21949654

71. Basu Roy A, Sauer K. Diguanylate cyclase NicD-based signalling mechanism of nutrient-induced dispersion by Pseudomonas aeruginosa. Mol Microbiol. 2014;94(4):771–93. doi: 10.1111/mmi.12802 25243483

72. Dahlstrom KM, Collins AJ, Doing G, Taroni JN, Gauvin TJ, Greene CS, et al. A Multimodal strategy used by a large c-di-GMP network. J Bacteriol. 2018;200(8):e00703–17. doi: 10.1128/JB.00703-17 29311282

73. Staudinger BJ, Muller JF, Halldórsson S, Boles B, Angermeyer A, Nguyen D, et al. Conditions associated with the cystic fibrosis defect promote chronic Pseudomonas aeruginosa infection. Am J Respir Crit Care Med. 2014;189(7):812–24. doi: 10.1164/rccm.201312-2142OC 24467627

74. Vogel HJ, Bonner DM. Acetylornithinase of Escherichia coli: Partial purification and some properties. J Biol Chem. 1956;218:97–106. 13278318

75. Hmelo LR, Borlee BR, Almblad H, Love ME, Randall TE, Tseng BS, et al. Precision-engineering the Pseudomonas aeruginosa genome with two-step allelic exchange. Nat Protoc. 2015;10(11):1820–41.

76. Choi K-H, Schweizer HP. mini-Tn7 insertion in bacteria with single attTn7 sites: example Pseudomonas aeruginosa. Nat Protoc. 2006;1(1):153–61. doi: 10.1038/nprot.2006.24 17406227

77. Zhao K, Tseng BS, Beckerman B, Jin F, Gibiansky ML, Harrison JJ, et al. Psl trails guide exploration and microcolony formation in Pseudomonas aeruginosa biofilms. Nature. 2013;497(7449):388–91. doi: 10.1038/nature12155 23657259

78. Choi K-H, Gaynor JB, White KG, Lopez C, Bosio CM, Karkhoff-Schweizer RR, et al. A Tn7-based broad-range bacterial cloning and expression system. Nat Methods. 2005;2(6):443–8. doi: 10.1038/nmeth765 15908923

79. Goeres DM, Hamilton MA, Beck NA, Buckingham-Meyer K, Hilyard JD, Loetterle LR, et al. A method for growing a biofilm under low shear at the air-liquid interface using the drip flow biofilm reactor. Nat Protoc. 2009;4(5):783–8. doi: 10.1038/nprot.2009.59 19528953

80. Byrd MS, Sadovskaya I, Vinogradov E, Lu H, Sprinkle AB, Richardson SH, et al. Genetic and biochemical analyses of the Pseudomonas aeruginosa Psl exopolysaccharide reveal overlapping roles for polysaccharide synthesis enzymes in Psl and LPS production. Mol Microbiol. 2009;73(4):622–38. doi: 10.1111/j.1365-2958.2009.06795.x 19659934

81. DiGiandomenico A, Warrener P, Hamilton M, Guillard S, Ravn P, Minter R, et al. Identification of broadly protective human antibodies to Pseudomonas aeruginosa exopolysaccharide Psl by phenotypic screening. J Exp Med. 2012;209(7):1273–87. doi: 10.1084/jem.20120033 22734046

82. Winsor GL, Griffiths EJ, Lo R, Dhillon BK, Shay JA, Brinkman Fiona SL. Enhanced annotations and features for comparing thousands of Pseudomonas genomes in the Pseudomonas genome database. Nucleic Acids Res. 2016;44(D1):D646–D53. doi: 10.1093/nar/gkv1227 26578582

83. Dunnen JTd, Antonarakis SE. Mutation nomenclature extensions and suggestions to describe complex mutations: A discussion. Hum Mutat. 2000;15(1):7–12. doi: 10.1002/(SICI)1098-1004(200001)15:1<7::AID-HUMU4>3.0.CO;2-N 10612815

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