Reduction in chemotaxis of TM1040 toward untreated and heated P. piscicida homogenates by external addition of known attractants

TreatmentaNo. of bacteria per capillary (CFU, 104)b with:
ControldAttractant added to external bufferc
DMSP% ReductioneMethionine% ReductionValine% Reduction
None7.24 (± 1.39)3.33 (± 0.15)54.013.03 (± 0.32)58.151.53 (± 0.15)78.87
Heat3.51 (± 0.35)3.10 (± 0.16)11.681.80 (± 0.11)48.720.91 (± 0.24)74.07
  • a Chemotaxis of TM1040 toward heated (80°C for 15 min) or untreated P. piscicida homogenates was measured using the capillary assay (see Materials and Methods).

  • b Standard deviation is given in parentheses.

  • c Prior to the assay, DMSP, methionine, or valine was added to external buffer containing motile cells of TM1040 at a final concentration of 200 μM and mixed to homogeneity.

  • d The control was buffer only.

  • e % Reduction, the percent reduction in CFU per capillary compared to the control.