Lipopeptide families at the interface between pathogenic and beneficialPseudomonas-plant interactions

Abstract

Lipopeptides (LPs) are a prominent class of molecules among the steadily growing spectrum of specialized metabolites retrieved from Pseudomonas, in particular soil-dwelling and plant-associated isolates. Among the multiple LP families, pioneering research focussed on phytotoxic and antimicrobial cyclic lipopeptides (CLPs) of the ubiquitous plant pathogen Pseudomonas syringae (syringomycin and syringopeptin). Their non-ribosomal peptide synthetases (NRPSs) are embedded in biosynthetic gene clusters (BGCs) that are tightly co-clustered on a pathogenicity island. Other members of the P. syringae group (Pseudomonas cichorii) and some species of the Pseudomonas asplenii group and Pseudomonas fluorescens complex have adopted these biosynthetic strategies to co-produce their own mycin and peptin variants, in some strains supplemented with an analogue of the P. syringae linear LP (LLP), syringafactin. This capacity is not confined to phytopathogens but also occurs in some biocontrol strains, which indicates that these LP families not solely function as general virulence factors. We address this issue by scrutinizing the structural diversity and bioactivities of LPs from the mycin, peptin, and factin families in a phylogenetic and evolutionary perspective. BGC functional organization (including associated regulatory and transport genes) and NRPS modular architectures in known and candidate LP producers were assessed by genome mining.

The Ever-Expanding <em>Pseudomonas</em> Genus: Description of 43 New Species and Partition of the <em>Pseudomonas Putida </em>Group

“…the presence of tandem TE-domains and the absence of epimerization domains) and synteny (i.e. number of modules and distribution along the NRPS genes), all based on previously described CLP NRPS gene clusters annotations [35,36]. All known and newly identified strains carrying CLP BGCs together with their affiliation to CLP families and the accession numbers of their NRPS genes are presented in Table S7.…”

“…CLPs are specialized metabolites that often support important ecological functions including cooperation, phytopathogenicity or antagonism [29,36,39]. CLPs consist of a fatty acid tail attached to a cyclized oligopeptide and are synthesized by Non-Ribosomal Peptide Synthetases (NRPSs) [29,35].…”

“…The modularity of these enzymes enable Pseudomonas strains to produce a wide diversity of CLPs, resulting in their classification in several families [28,29,35]. The relationship between CLP diversity and Pseudomonas taxonomy was recently highlighted and it was demonstrated that certain CLP families were exclusive to specific subgroups of P. fluorescens [30,31,36]. On the other hand, the P. putida group was demonstrated to host CLP producers from different families [30,31].…”

“…Further analyses, chemical characterization and/or a hybrid assembly based on long read sequencing and Illumina sequencing, are needed to identify the CLPs. We previously highlighted, in the type strains of P. asplenii and P. fucovaginae, a NRPS system predicted to assemble a lipotridecapeptide (LP-13) but this metabolite still awaits chemical and functional characterization [36]. A putative LP-13 biosynthesis gene cluster is also present in the genome of P. tructae.…”

Biologization of grape growing technologies to obtain safe and high-quality products

“…Microorganisms isolated from nature and introduced again into natural conditions as plant protection agents allow to avoid undesirable changes in biocenoses and to preserve useful species. The main advantage of microbiological plant protection agents based on naturally occurring viruses, bacteria, fungi is their specificity -the ability to infect certain objects without harming humans, animals, birds and useful insects [6,7].…”