Article Figures & Data
Figures
- FIG. 1.
Representative cyclic voltammetry (CV) of Δphz mutant cultures of P. aeruginosa PA14 incubated anaerobically in 100 ml MOPS medium containing 20 mM glucose, supplemented with 90 μM PYO (dark trace) or no PYO (light trace). PYO is the only electrochemically active component with single anodic (oxidation) and cathodic (reduction) peaks characteristic of itself. CV experiments were performed at 100 mV/s, with electrodes consisting of a stationary gold disk working electrode (BASi), an Ag/AgCl reference electrode, and a Pt counter electrode.
- FIG. 2.
PYO (a), PCA (b), and 1-OHPHZ (c) function as electron shuttles (▪) to promote anaerobic survival of the Δphz mutant of P. aeruginosa PA14 when cells are incubated anaerobically in MOPS-buffered medium containing 20 mM d-glucose and ∼90 μM phenazine (PYO, PCA, or 1-OHPHZ) and with the graphite rod working electrode poised at +0.2 V versus that of the NHE. Survival was determined by measuring the number of CFU on LB agar plates. The number of CFU of Δphz anaerobic incubations without phenazine (▿), poised potential (▵), or both (⋄) served as a control. Error bars represent standard deviations from at least triplicate samples in each experimental set. Plots represent results from at least three independent experiments.
- FIG. 3.
Anaerobic survival of the Δphz mutant of P. aeruginosa PA14 without d-glucose and in the presence of 20 mM d-glucose for cells incubated in MOPS medium containing ∼90 μM PYO, with the graphite rod working electrode poised at +0.2 V versus that of the NHE. Survival was determined by the number of CFU on LB agar plates. Error bars represent standard deviations from triplicate samples in each experimental set. Plots represent results from two independent experiments.
Tables
- TABLE 1.
Properties and results summarized from experiments for testing the roles of endogenous phenazines and other type redox-active compounds in promoting anaerobic survival of P. aeruginosa
aFrom reference 39.
bE0′ values were measured in aqueous solution at pH 7 in this study.
cFrom reference 10.
dFrom reference 16.
eFrom references 25 and 26.
f—, not applicable; present in its reduced form.
gThe oxidized form is shown for all entries except homogentisic acid, for which the reduced form is shown.
