Motility influences biofilm architecture in Escherichia coli
Eight Escherichia coli strains were studied in minimal medium with a continuous flow system using confocal microscopy. K12 wild-type strains ATCC 25404 and MG1655 formed the best biofilms (∼43 μm thick, 21 to 34% surface coverage). JM109, DH5α, and MG1655 motA formed intermediate biofilms (∼13 μm thick, 41 to 58% surface coverage). BW25113, MG1655 qseB, and MG1655 fliA had poor biofilms (surface coverage less than 5%). The best biofilm-formers, ATCC 25404 and MG1655, displayed the highest motility, whereas the worst biofilm former, BW25113, was motility-impaired. The differences in motility were due to differences in expression of the motility loci qseB, flhD, fliA, fliC, and motA (e.g., qseB expression in MG1655 was 139-fold higher than BW25113 and 209-fold higher than JM109). Motility affected the biofilm architecture as those strains which had poor motility (E. coli JM109, E. coli MG1655 motA, and DH5α) formed flatter microcolonies compared with MG1655 and ATCC 25404, which had more dramatic vertical structures as a result of their enhanced motility. The presence of flagella was also found to be important as qseB and fliA mutants (which lack flagella) had less biofilm than the isogenic paralyzed motA strain (threefold less thickness and 15-fold less surface coverage).
- Elvers KT, Lappin-Scott HM (2000) Biofilms and biofouling, 2nd edn. Academic, San Diego, CaliforniaGoogle Scholar
- Hansen MC, Palmer RJ Jr, Udsen C, White DC, Molin S (2001) Assessment of GFP fluorescence in cells of Streptococcus gordonii under conditions of low pH and low oxygen concentration. Microbiol 147:1383–1391Google Scholar
- Heydorn A, Ersboll B, Kato J, Hentzer M, Parsek MR, Tolker-Nielsen T, Givskov M, Molin S (2002) Statistical analysis of Pseudomonas aeruginosa biofilm development: impact of mutations in genes involved in twitching motility, cell-to-cell signaling, and stationary-phase sigma factor expression. Appl Environ Microbiol 68:2008–2017CrossRefPubMedGoogle Scholar
- Heydorn A, Nielsen AT, Hentzer M, Sternberg C, Givskov M, Ersbøll BK, Molin S (2000) Quantification of biofilm structures by the novel computer program COMSTAT. Microbiol 146:2395–2407Google Scholar
- Rodriguez RL, Tait RC (1983) Recombinant DNA techniques: an introduction. Benjamin/Cummings Publishing, Menlo Park, CAGoogle Scholar
- Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning, a laboratory manual, 2nd ed. Cold Spring Harbor Laboratory, Cold Spring Harbor, NYGoogle Scholar