Location: Forage Seed and Cereal ResearchTitle: Unexpected distribution of the 4-formylaminooxyvinylglycine (FVG) biosynthetic pathway in Pseudomonas and beyond
Submitted to: PLoS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/13/2021
Publication Date: 4/23/2021
Citation: Davis, E.W. II, Okrent, R.A., Manning, V., Trippe, K.M. 2021. Unexpected distribution of the 4-formylaminooxyvinylglycine (FVG) biosynthetic pathway in Pseudomonas and beyond. PLoS ONE. 16(4). https://doi.org/10.1371/journal.pone.0247348.
Interpretive Summary: A bacteria that is native to grass seed fields in the Willamette Valley of Oregon, Pseudomonas fluorescens WH6, is known to produce an herbicide that arrests the germination of grasses. This herbicide, known as 4-formylaminooxyvinylglycine (FVG), has been well characterized. Despite this, only a few strains of bacteria are known to produce this compound. We used our previous knowledge of the gene cluster that encodes the FVG biosynthetic pathway (gvg) to determine if this gene cluster is widespread amongst other bacteria. We learned that the gene cluster is relatively rare, and is generally found within one specific group of fluorescent pseudomonads. However, other groups of bacteria, including certain strains of Pseudomonas syringae, Thiomonas, Burkholderia and Pantoea also encode this cluster. Our results suggest that the the gvg biosynthetic gene cluster has been transfered to other bacteria by lateral gene transfer. Because FVG is produced in a wide variety of strains, our results also suggest that FVG production is evolutionarily useful for a variety of bacteria living in a variety of plant or soil-related environments.
Technical Abstract: The biological herbicide and antibiotic 4-formylaminooxyvinylglycine (FVG) was originally isolated from several rhizosphere-associated strains of Pseudomonas fluorescens. Biosynthesis of FVG is dependent on the gvg biosynthetic gene cluster in P. fluorescens. In this investigation, we used comparative genomics to identify strains with the genetic potential to produce FVG due to presence of a gvg gene cluster. These strains primarily belong to two groups of Pseudomonas, P. fluorescens and P. syringae, however, a few strains with the gvg cluster were found outside of Pseudomonas. Mass spectrometry confirmed that all tested strains of the P. fluorescens species group produced FVG. However, P. syringae strains did not produce FVG under standard conditions. Several lines of evidence regarding the transmission of the gvg cluster suggest that it was introduced multiple times through horizontal gene transfer within the Pseudomonas lineage as well as in select lineages of Thiomonas, Burkholderia and Pantoea. Together, these data broaden our understanding of the evolution and diversity of FVG biosynthesis. In the course of this investigation, additional gene clusters containing only a subset of the genes required to produce FVG were identified in a broad range of bacteria, including many non-pseudomonads. These clusters likely produce novel metabolites.