Antibiotic Regulation in the Biological Control Bacterium Pseudomonas fluorescens Strain Pf-5
EPA Grant Number: U915213Title: Antibiotic Regulation in the Biological Control Bacterium Pseudomonas fluorescens Strain Pf-5
Investigators: Whistler, Cheryl A.
Institution: Oregon State University
EPA Project Officer: Boddie, Georgette
Project Period: January 1, 1997 through January 1, 2000
Project Amount: $102,000
RFA: STAR Graduate Fellowships (1997)
Research Category: Fellowship - Molecular Biology/Genetics , Biology/Life Sciences , Academic Fellowships
Description:
Objective:The objective of this research project is to understand the regulation of antibiotic production in the biological control bacterium Pseudomonas fluorescens Pf-5. When applied to seeds, this bacterium produces several antibiotics, including pyoluteorin and 2,4-diacetylphloroglucinol, which protect seeds and roots from infection by fungal plant pathogens including Pythium ultimum. This research will aid in understanding how different environmental factors can influence antibiotic production by Pf-5 and the success of this bacterium as a biological control agent.
Approach:An existing collection of Tn5 insertion mutants of Pf-5 with altered antibiotic production profiles is being utilized to identify previously undescribed genes that regulate antibiotic production. The role of a gene in antibiotic regulation is confirmed through marker-exchange mutagenesis. Sequence analysis of a corresponding wild-type gene provides theoretical information of its identity and role in antibiotic regulation, as well as possible environmental factors that may influence regulation. Identification of regulatory genes aids in the understanding of regulatory pathways. Of particular interest to me is how different genes interact to influence antibiotic production, perhaps in regulatory cascades, and the role of stress response in antibiotic regulation. To date, three genes that regulate antibiotic production have been identified: GacA, GacS, and RpoS.
Supplemental Keywords:fellowship, Tn5 insertion mutant, pyoluteorin, antibiotic production, Pseudomonas fluorescens, regulatory genes, Pythium ultimum, Pf-5, fungal plant pathogens. , Ecosystem Protection/Environmental Exposure & Risk, Scientific Discipline, RFA, Ecosystem/Assessment/Indicators, Molecular Biology/Genetics, Biology, exploratory research environmental biology, Ecological Indicators, Biochemistry, Ecological Effects - Environmental Exposure & Risk, Ecology and Ecosystems, Genetics, fungal plant pathogens, ecological research, antibacterial agents, pseudomonas fluorescens, biological control agents, gene-environment interaction, molecular genetics, genetic consequences, molecular ecology, environmental stress-responsive gene expression