Pyocyanin, a Metabolite of Pseudomonas Aeruginosa, Exhibits Antifungal Drug Activity Through Inhibition of a Pleiotropic Drug Resistance Subfamily FgABC3

Abstract

The fungus Fusarium graminearum is the causative agent of economically significant plant diseases such as Fusarium Healed Blight (FHB) of cereals, its mycotoxins as deoxynivalenol (DON), Nivalenol (NIV) and Zearalenone (ZEN) contaminate wheat and other grains. The objectives of the present study were to determine the mechanism by which the bacterium Pseudomonas aeruginosa inhibits the growth of F. graminearum. Our results indicate that P. aeruginosa metabolites as pyocyanin has effective antifungal properties. Pyocyanin was produced by P. aeruginosa when cultured on mineral salt medium and reached a maximum concentration after 72 h. Pyocyanin significantly decreased mycotoxins of F. graminearum, a 25 mg/ml of pyocyanin for 72 h decreased DON by 68.7% and NIV by 57.7%.Real-Time PCR analysis demonstrated that the antifungal effect is mediated by downregulation of the Pleiotropic Drug Resistance (PDR) subfamily FgABC3. 25 mg/ml of pyocyanin decreased FgABC3-mRNA by 60%, inhibited the fungal growth and decreased the area of mycelial growth at 12, 24, 36 and 72 h post incubation by 40–50%. Deletion of FgABC3 led to enhanced accumulation of DON and NIV by 40 and 60%, respectively.The data presented in this report may have significance in understanding mechanism by which certain bacterial metabolites exert a beneficial effect and for developing antifungal drugs.

Potential Application of Rhizobacteria Isolated from the Central Highland of Vietnam as an Effective Biocontrol Agent of Robusta Coffee Nematodes and as a Bio-Fertilizer

“…Earlier reports prove that Pseudomonas aeruginosa has a wide range of important applications in environment management [34][35][36], in industry for the production of various secondary metabolites (Rhamnolipid, Vanillin, enzymes, and pigments) [36][37][38][39][40][41], as well as its potential use in agriculture [42][43][44][45][46][47][48][49][50][51]. This bacterial genus has been proven to have potential use as a plant growth promoter [42] and produces an anti-plant virus agent [43].…”

“…This bacterial genus has been proven to have potential use as a plant growth promoter [42] and produces an anti-plant virus agent [43]. In particular, Pseudomonas aeruginosa and its secondary metabolites have been widely used for controlling numerous plant-pathogen fungal strains [44][45][46][47][48]. However, there are several reports on the assessment of nematicidal activity of Pseudomonas aeruginosa against several nematodes, including banana, tomato, and okra root-knot nematodes [49][50][51].…”

“…as its potential use in agriculture [42][43][44][45][46][47][48][49][50][51]. This bacterial genus has been proven potential use as a plant growth promoter [42] and produces an anti-plant virus ag In particular, Pseudomonas aeruginosa and its secondary metabolites have been wid for controlling numerous plant-pathogen fungal strains [44][45][46][47][48].…”

“…as its potential use in agriculture [42][43][44][45][46][47][48][49][50][51]. This bacterial genus has been proven potential use as a plant growth promoter [42] and produces an anti-plant virus ag In particular, Pseudomonas aeruginosa and its secondary metabolites have been wid for controlling numerous plant-pathogen fungal strains [44][45][46][47][48]. However, there eral reports on the assessment of nematicidal activity of Pseudomonas aeruginosa several nematodes, including banana, tomato, and okra root-knot nematodes There is also no report of the nematicidal effect of this genus against coffee nem Thus, this study shows for the first time the potential nematicidal effect of Pseu aeruginosa against coffee nematodes J2 and its egg hatching and adds to the knowledge of the biological activities of Pseudomonas aeruginosa.…”

“…The yields of these PGPCs were 231 µg/mL (IAA), 2702 µg/mL (GA3), 36.8 µg/mL (kinetin), and 7.71 µg/mL (zeatin). In addition, the culture broth contained a dark green pigment, which is well-known to be Pyocyanin, produced by Pseudomonas aeruginosa [46,52]. Pyocyanin is a potential biocontrol compound against a vast array of plant-pathogen diseases [53], and as such, it may be a potent plant-promoting agent via its indirect mode of action [11,13,[54][55][56][57].…”