Environ Microbiol
Department of Crop Protection, Laboratory of Phytopathology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium.
Published: March 2008
In this study, the putative role of phenazines and rhamnolipid-biosurfactants, antagonistic metabolites produced by Pseudomonas aeruginosa PNA1, was tested in the biological control of Pythium splendens on bean (Phaseolus vulgaris L) and Pythium myriotylum on cocoyam (Xanthosoma sagittifolium L Schott). A rhamnolipid-deficient and a phenazine-deficient mutant of PNA1 were used either separately or jointly in plant experiments. When the mutants were applied separately, no disease-suppressive effect was observed, although both mutants still produced one of the antagonistic compounds (phenazines or rhamnolipids). When the mutants were concurrently introduced in the soil, the biocontrol activity was restored to wild-type levels. Bean seeds developed significantly less pre-emergence damping-off caused by P. splendens when treated with a mixture of purified phenazine-1-carboxamide and rhamnolipids than with any of the chemicals alone. When phenazines and rhamnolipids were combined at concentrations that had no observable effects when the metabolites were applied separately, mycelial growth of P. myriotylum was significantly reduced. In addition, microscopic analysis revealed substantial vacuolization and disintegration of Pythium hyphae after incubation in liquid medium amended with both metabolites. Results of this study indicate that phenazines and biosurfactants are acting synergistically in the control of Pythium spp.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1462-2920.2007.01501.x | DOI Listing |
Microb Biotechnol
January 2024
Departamento de Biología Molecular y Biotecnología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Coyoacan, Mexico.
Rhamnolipids (RL) are biosurfactants naturally produced by the opportunistic pathogen Pseudomonas aeruginosa. Currently, RL are commercialized for various applications and produced by Pseudomonas putida due to the health risks associated with their large-scale production by P. aeruginosa.
View Article and Find Full Text PDFWorld J Microbiol Biotechnol
February 2021
Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Lucknow, UP, 226025, India.
Biosurfactants are environment compatible surface-active biomolecules with multifunctional properties which can be utilized in various industries. In this study a biosurfactant producing novel plant growth promoting isolate Pseudomonas guariconensis LE3 from the rhizosphere of Lycopersicon esculentum is presented as biostimulant and biocontrol agent. Biosurfactant extracted from culture was characterized to be mixture of various mono- and di-rhamnolipids with antagonistic activity against Macrophomina phaseolina, causal agent of charcoal rot in diverse crops.
View Article and Find Full Text PDFJ Biotechnol
January 2020
Department of Zoology, University of Delhi, Delhi 110007, India. Electronic address:
Biosurfactant - Rhamnolipids (RLs) and antibacterial toxin - pyocyanin (PYO) produced by Pseudomonas aeruginosa strains have great potential for biotechnological applications. Generally, RLs are produced as a mixture of di-rhamnolipids (di-RLs) and mono-rhamnolipids (mono-RLs). Mono-RLs possess superior emulsification and antimicrobial properties and are costlier than di-RLs.
View Article and Find Full Text PDFMicrob Pathog
June 2018
School of Biological Sciences and Technology, Chonnam National University, 77 Youngbong-ro, Buk-gu, Gwangju 61186, Republic of Korea; Higher Education Center for Bioregulator Research, Chonnam National University, 77 Youngbong-ro, Buk-gu, Gwangju 61186, Republic of Korea. Electronic address:
Three strains of Pseudomonas aeruginosa were isolated: wild-type (WT, NO4) showed normal quorum sensing (QS), whereas QSD3 and QSD7 were QS-deficient (QSD) containing limited N-butyryl homoserine lactone (C4-HSL). The autoinducer activity produced by NO4 was found to be at least 50-fold higher than those by the QSD3 and the QSD7 strains. The QSDs produced lower levels of phenazine compounds (pyocyanin), siderophores (pyoverdine) and biosurfactants (rhamnolipids) than NO4.
View Article and Find Full Text PDFJ Med Microbiol
February 2016
Department of Biology, Faculty of Arts and Science, Uludag University, 16059, Bursa, Turkey.
The role of quorum sensing (QS) in the regulation of virulence factor production in Pseudomonas aeruginosa is well established. Increased antibiotic resistance in this bacterium has led to the search for new treatment options, and inhibition of the QS system has been explored for potential therapeutic benefits. If the use of QS inhibitory agents were to lead to a reduction in bacterial virulence, new approaches in the treatment of P.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!
© LitMetric 2025. All rights reserved.