TABLE 2.
Quantification of biofilm formation and cell attachment of E. coli pathotypes using a microfluidic systema
| Assay, strain, and treatment | No. of particles | Avg particle size (pixels)b | % of area covered | Biomass (μm3/μm2)c | Height (μm) |
|---|---|---|---|---|---|
| Biofilm formation | |||||
| EHEC EDL933 | 1,828 (±250) | 10.5 (±5) | 18 (±5) | 3.88 (±1.06) | 31 (±3) |
| EHEC Sakai | 1,430 (±127) | 30.0 (±7.4) | 41 (±12) | 2.64 (±0.86) | 35 (±4) |
| C. rodentium DBS100 | 1,517 (±148) | 21.5 (±8.3) | 31 (±6) | 2.06 (±0.42) | 23 (±5 |
| AIEC LF82 | 14 (±7) | 7,132.1 (±258.9) | 95 (±14) | 2.44 (±1.85) | 37 (±5) |
| EPEC | 123 (±22) | 623.7 (±250.6) | 73 (±17) | 8.43 (±1.23) | 38 (±3) |
| aEPEC ECL1001 | 2,644 (±311) | 13.0 (±4.8) | 33 (±9) | 3.05 (±0.65) | 22 (±6) |
| K-12 MG1655 | 45 (±8) | 1,967.4 (±127.2) | 84 (±15) | 7.85 (±0.92) | 27 (±4) |
| EAEC 17.2 | 23 (±6) | 3,876.7 (±289.6) | 85 (±17) | NDd | NDd |
| SEPEC 31A | 144 (±24) | 541.4 (±114.9) | 74 (±8) | NDd | NDd |
| APEC | 14 (±4) | 7,148.6 (±356.8) | 95 (±6) | 8.08 (±1.04) | 26 (±2) |
| UPEC 536 | 97 (±17) | 917.1 (±95.8) | 85 (±13) | 10.39 (±0.76) | 31 (±4) |
| UPEC F11 | 78 (±13) | 1,120.9 (±108.3) | 83 (±12) | 17.28 (3.02) | 50 (±7) |
| UPEC CFT073 | 1,100 (±206) | 45.9 (±35.1) | 36 (±21) | 2.54 (±1.56) | 22(±14) |
| UPEC J96 | 12 (±5) | 8,197.8 (±312.9) | 93 (±7) | 9.53 (±1.03) | 29 (±4) |
| Enzymatic treatment | |||||
| K-12 MG1655 | |||||
| Control | 102 (±21) | 575.3 (±148.2) | 70 (±8) | NAe | NA |
| Proteinase K | 383(±25) | 30.6 (±14.9) | 14 (±3) | NA | NA |
| DNase | 124 (±19) | 405.4 (±74.9) | 64 (±9) | NA | NA |
| EPEC | |||||
| Control | 285 (±34) | 165.9 (±30.8) | 58 (±16) | NA | NA |
| Proteinase K | 331 (±14) | 22.8 (±11.6) | 9 (±2) | NA | NA |
| DNase | 198 (±11) | 247.9 (±21.6) | 64 (±14) | NA | NA |
| AIEC LF82 | |||||
| Control | 100 (±5) | 580.7 (±210.6) | 71 (±17) | NA | NA |
| Proteinase K | 385 (±37) | 83.3 (±34.5) | 39 (±11) | NA | NA |
| DNase | 178 (±16) | 270.8 (±97.3) | 61 (±10) | NA | NA |
| Cell attachment | |||||
| Negative control | 5 (±3) | 1.4 (±0.5) | 0.07 (±0.05) | NDf | NDf |
| K12 MG1655 | 41 (±10) | 2.9 (±0.6) | 1 (±0.6) | NDf | NDf |
| EHEC EDL933 | 200 (±16) | 6.5 (±0.9) | 13 (±2) | 2.17 (±0.31) | 25 (±2) |
| EHEC Sakai | 61 (±11) | 39.4 (±5.6) | 24 (±4) | 1.99 (±0.21) | 20 (±1) |
| C. rodentium DBS100 | 32 (±5) | 230.7 (±50.9) | 73 (±9) | 1.36 (±0.12) | 8 (±1) |
| EPEC | 78 (±19) | 64.7 (±14.3) | 48 (±5) | 3.18 (±0.32) | 28 (±3) |
| aEPEC ECL1001 | 111 (±23) | 11.1 (±3.8) | 12 (±2) | 0.31 (±0.09) | 19 (±2) |
| EAEC 17.2 | 70 (±9) | 48.6 (±6.5) | 34 (±5) | 5.23 (±0.83) | 33 (±4) |
| SEPEC 31A | 276 (±31) | 7.0 (±1.2) | 19 (±2) | 1.82 (±0.43) | 39 (±3) |
| UPEC CFT073 | 83 (±16) | 11.3 (±1.6) | 9 (±3) | 0.25 (±0.07) | 13 (±2) |
a
Values are averages (standard errors) for 3 independent biological replicates.
b
Two pixels are approximately equivalent to 1 bacterial cell.
c
ND, not determined; NA, not applicable.
d
The microfluidic channel was blocked and did not allow effective penetration of the dye.
e
NA, images were not captured with a confocal microscope.
f
The absence of fluorescence in the mCherry channel did not allow for the detection of measureable biofilms.