Pseudomonas Fluorescens

Pseudomonas Fluorescens

There are two strains of Pseudomonas fluorescents associated with Dictyostelium discoideum. One strain serves as a food source and the other strain does not. The main genetic difference between these two strains is a mutation of the global activator gene called gacA. This gene plays a key role in gene regulation; when this gene is mutated in the nonfood bacterial strain, it is transformed into a food bacterial strain To be specific, certain P. fluorescens isolates produce the secondary metabolite 2,4-diacetylphloroglucinol (2,4-DAPG), the compound found to be responsible for antiphytopathogenic and biocontrol properties in these strains. The phl gene cluster encodes factors for 2,4-DAPG biosynthesis, regulation, export, and degradation. Eight genes, phlHGFACBDE, are annotated in this cluster and conserved organizationally in 2,4-DAPG-producing strains of P. fluorescens. Of these genes, phlD encodes a type III polyketide synthase, representing the key biosynthetic factor for 2,4-DAPG production. PhlD shows similarity to plant chalcone synthases and has been theorized to originate from horizontal gene transfer.Phylogenetic and genomic analysis, though, has revealed that the entire phl gene cluster is ancestral to P. fluorescens, many strains have lost the capacity, and it exists on different genomic regions among strains.


Last Updated on: Nov 25, 2024

Global Scientific Words in Immunology & Microbiology