TABLE 2

Static biofilm formation on PS and SSC after 48 h of incubation and biofilm formation in FC channel after 24 ha

StrainCharacteristic(s)OD/ODc category for 96-well PS platesbOverall scoreOD/ODc category for SSCbBiofilm formation in FC channelc
LBLBnoSRPSMdilABTCAARPSMABTCAA
12°C28°C37°C12°C28°C37°C12°C28°C37°C12°C28°C37°C12°C37°C
FAM19195HR433314220
FAM21805HR142312313323+
FAM21807HR13213313219
FAM21808HR33118
FAM21843HR1421413344330+
FAM21845HR433443243444421
FAM22636HR1311212212319
FAM22639HR3223123223326
FAM22791HR2222223312223
FAM22808HR141413323224
FAM22891HR3213213332427
FAM22936HR4224112233327+
FAM22940HR113312213
FAM22947HR2121124423224
FAM22954HR24224213334434
FAM22961HR23123113334228
FAM22962HR324211+
FAM22963HR33133213344232
FAM23012HR4333222233431+
FAM23014HR3323223333330
FAM23016HR33234212244333
FAM23030HR23134112344230
FAM23031HR1111112313116
FAM23078HR1112214315
FAM23092HR3333232223430+
FAM23093HR4323321223328+
FAM23101HR3324323243433+
FAM23106HR112214314
FAM23109HR12222212234326
FAM23113HR3324222333330
FAM21846HS1131213315
FAM22942HS1441432224431+
FAM22956HS1441343323331
FAM22996HS134
FAM22321HS, ESBL111123110
FAM22871HS, ESBL1411412114222+
K-12 MG1655HS1411412224224+
Overall score6192556085518909575114971 positive11 positives
  • a LB, Luria-Bertani Lennox broth; LBnoS, LB without addition of NaCl; RPSM and RPSMdil, reconstituted powdered skim milk at 10.5% and 0.2% (wt/vol), respectively; ABTCAA, AB minimal medium with 0.5% Casamino Acids as a carbon source (56); HR, heat resistant; HS, heat sensitive; ESBL, extended-spectrum β-lactamase; FC, Bioflux flow cells; SSC, stainless steel coupons.

  • b Numbers in columns indicate categories defined by OD/ODc ratios (79). The cutoff value was determined as follows: ODc = average ODnegative control + 3× SD(ODnegative control). The categories are indicated as follows: −, OD ≤ ODc; 1, ODc < OD ≤ 2× ODc; 2, 2× ODc < OD ≤ 4× ODc; 3, 4× ODc < OD ≤ 8× ODc; and 4, 8× ODc < OD.

  • c +, formation of biofilm within the FC channel for each replicate.