Properties of wild-type strain P. fluorescens SS101 and its five surfactant-deficient Tn5 mutants

SS101Tn5 mutant:
Halo formationa+
Drop collapseb+
Foam formationc+
Surface tension (mN m−1)d29.764.356.060.056.562.0
β-Galactosidase activitye+++++
Phospholipase Cg++++++
Cessation of zoospore motilityi+
Zoospore lysisi+
  • a Evaluated on SW medium after 3 to 5 days of growth at 25°C.

  • b Cell suspensions (OD600 = 1) were tested on an oily surface for the ability to cause the collapse of a drop of water.

  • c Foam formation after cell suspensions (OD600 = 1) were vigorously shaken.

  • d Surface tensions of cell suspensions (OD600 = 1).

  • e Evaluated on KMB plates containing X-Gal and IPTG after 48 h of growth at 25°C.

  • f Tested on skim milk plates.

  • g Tested on egg yolk plates.

  • h Tested on Pseudomonas agar Funder near-UV light (360 nm).

  • i Zoospore motility and lysis were observed microscopically after bacterial cell suspensions (OD600 = 1) were mixed with zoospore suspensions of P. ultimum var. sporangiiferum, A. candida, or P. infestans (103 to 104 zoospores ml−1) in a 1:1 (vol/vol) ratio.

  • j +, positive reaction;− , negative reaction.