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RHIZOCLIP: Ecological roles of cyclic lipopeptides from plant-beneficial rhizobacteria

Goal: Employing chemical-biology approaches to decipher primary functions of secondary metabolites

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Feyisara Eyiwumi Oni
added a research item
Pseudomonas lipopeptides (Ps-LPs) play crucial roles in bacterial physiology, host–microbe interactions and plant disease control. Beneficial LP producers have mainly been isolated from the rhizosphere, phyllosphere and from bulk soils. Despite their wide geographic distribution and host range, emerging evidence suggests that LP-producing pseudomonads and their corresponding molecules display tight specificity and follow a phylogenetic distribution. About a decade ago, biocontrol LPs were mainly reported from the P. fluorescens group, but this has drastically advanced due to increased LP diversity research. On the one hand, the presence of a close-knit relationship between Pseudomonas taxonomy and the molecule produced may provide a startup toolbox for the delineation of unknown LPs into existing (or novel) LP groups. Furthermore, a taxonomy–molecule match may facilitate decisions regarding antimicrobial activity profiling and subsequent agricultural relevance of such LPs. In this review, we highlight and discuss the production of beneficial Ps-LPs by strains situated within unique taxonomic groups and the lineage-specificity and coevolution of this relationship. We also chronicle the antimicrobial activity demonstrated by these biomolecules in limited plant systems compared with multiple in vitro assays. Our review further stresses the need to systematically elucidate the roles of diverse Ps-LP groups in direct plant–pathogen interactions and in the enhancement of plant innate immunity.
Léa Girard
added a research item
Pseudomonas lipopeptides (LPs) are involved in diverse ecological functions and have biotechnological potential associated with their antimicrobial and/or anti-proliferative activities. They are synthesized by multi-modular non-ribosomal peptide synthetases which, together with transport and regulatory proteins, are encoded by large biosynthetic gene clusters (BGCs). These secondary metabolites are classified in distinct families based on sequence and length of the oligopeptide, and size of the macrocycle, if present. Phylogeny of PleB, the MacB-like transporter that is part of a dedicated ATP-dependent tripartite efflux system driving export of Pseudomonas LPs, revealed a strong correlation with LP chemical diversity. As each LP BGC carries its cognate pleB , PleB is suitable as a diagnostic sequence for genome mining, allowing assignment of the putative metabolite to a particular LP family. In addition, pleB proved a suitable target gene for an alternative PCR method to detect LP-producing Pseudomonas , not relying on amplification of catalytic domains of the biosynthetic enzymes. Combined with amplicon sequencing, this approach enabled typing of Pseudomonas strains as potential producers of a LP belonging to one of ten different families, underscoring its value for strain prioritization. This was validated by chemical characterization of known LPs from three different families secreted by novel producers isolated from the rice or maize rhizosphere, namely the type strains of Pseudomonas fulva (putisolvin), Pseudomonas zeae (tensin) and Pseudomonas xantholysinigenes (xantholysin). In addition, a new member of the Bananamide family, prosekin, was discovered in the type strain of Pseudomonas prosekii , an Antarctic isolate. Importance Pseudomonas are ubiquitous bacteria able to thrive in a wide range of ecological niches and lipopeptides often support their lifestyle but also their interaction with other micro- and macro-organisms. Therefore, the production of lipopeptides is widespread among Pseudomonas strains. Consequently, Pseudomonas lipopeptide research affects not only chemists and microbiologists but touches a much broader audience, including biochemists, ecologists and plant biologists. In this study we present a reliable transporter gene-guided approach for the detection and/or typing of Pseudomonas lipopeptide producers. Indeed, it allows to readily assess the lipopeptide diversity among sets of Pseudomonas isolates and differentiate strains likely to produce known lipopeptides from producers of potentially novel lipopeptides. This work provides a valuable tool that can also be integrated in a genome mining strategy and adapted for the typing of other specialized metabolites.
Niels Geudens
added a research item
Pseudodesmin A (PSD) is a cyclic lipodepsipeptide produced by Pseudomonas that kills certain bacteria at MIC 1/2 in the single micromolar range, probably by permeabilizing their cellular membranes. Synthetic PSD variants, where the native decanoic (C10) acyl chain is varied in length from C4 to C8 and C12 to C14 carbons, were described to be not or less active against a panel of gram-positive strains, as compared to native PSD-C10. Here, we test the membrane-permeabilizing activity of PSD-C4 through PSD-C14 in terms of calcein release from liposomes, which is characterized in detail by the fluorescence-lifetime based leakage assay. Antagonistic concentrations and their chain length dependence agree well for liposome leakage and antimicrobial activity. The optimal chain length is governed by a balance between membrane partitioning (favoring longer chains) and the local perturbation or “damage” inflicted by a membrane-bound molecule (weakening for longer chains). Local perturbation, in turn, may involve at least two modes of action. Asymmetry stress between outer and inner leaflet builds up as the lipopeptides enter the outer leaflet and when it reaches a system-specific stability threshold, it causes a transient membrane failure that allows for the flip of some molecules from the outer to the inner leaflet. This cracking-in may be accompanied by transient, incomplete leakage from the aqueous cores of the liposomes observed, typically, for some seconds or less. The mismatch of the lipopeptide with the lipid leaflet geometry, expressed for example in terms of a spontaneous curvature, has two effects. First, it affects the threshold for transient leakage as described. Second, it controls the rate of equilibrium leakage proceeding as the lipopeptide has reached sufficient local concentrations in both leaflets to form quasi-toroidal defects or pores. Both modes of action, transient and equilibrium leakage, synergize for intermediate chain lengths such as the native, i.e., for PSD-C10. These mechanisms may also account for the reported chain-length dependent specificities of antibiotic action against the target bacteria.
Jelena Pršić
added a research item
The molecular basis of plant immunity triggered by microbial pathogens is being well characterized as a complex sequential process leading to the activation of defense responses at the infection site, but which may also be systemically expressed in all organs, a phenomenon also known as systemic acquired resistance (SAR). Some plant associated and beneficial bacteria are also able to stimulate their host to mount defenses against pathogen ingress via the phenotypically similar, induced systemic resistance phenomenon. Induced systemic resistance resembles SAR considering its mechanistic principle as it successively involves recognition at the plant cell surface, stimulation of early cellular immune-related events, systemic signaling via a fine-tuned hormonal crosstalk and activation of defense mechanisms. It thus represents an indirect but efficient mechanism by which beneficial bacteria with biocontrol potential improve the capacity of plants to restrict pathogen invasion. However, according to our current vision, induced systemic resistance is specific considering some molecular aspects underpinning these different steps. Here we overview the chemical diversity of compounds that have been identified as induced systemic resistance elicitors and thereby illustrating the diversity of plants species that are responsive as well as the range of pathogens that can be controlled via this phenomenon. We also point out the need for further investigations allowing better understanding how these elicitors are sensed by the host and the diversity and nature of the stimulated defense mechanisms.
Léa Girard
added a research item
The genus Pseudomonas hosts an extensive genetic diversity and is one of the largest genera among Gram-negative bacteria. Type strains of Pseudomonas are well known to represent only a small fraction of this diversity and the number of available Pseudomonas genome sequences is increasing rapidly. Consequently, new Pseudomonas species are regularly reported and the number of species within the genus is constantly evolving. In this study, whole genome sequencing enabled us to define 43 new Pseudomonas species and provide an update of the Pseudomonas evolutionary and taxonomic relationships. Phylogenies based on the rpoD gene and whole genome sequences, including, respectively, 316 and 313 type strains of Pseudomonas, revealed sixteen groups of Pseudomonas and, together with the distribution of cyclic lipopeptide biosynthesis gene clusters, enabled the partitioning of the P. putida group into fifteen subgroups. Pairwise average nucleotide identities were calculated between type strains and a selection of 60 genomes of non-type strains of Pseudomonas. Forty-one strains were incorrectly assigned at the species level and among these, 19 strains were shown to represent an additional 13 new Pseudomonas species that remain to be formally classified. This work pinpoints the importance of correct taxonomic assignment and phylogenetic classification in order to perform integrative studies linking genetic diversity, lifestyle, and metabolic potential of Pseudomonas spp.
Léa Girard
added a research item
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.
Thibault Meyer
added a research item
Some members of root-associated Bacillus species have been developed as biocontrol agents due to their contribution to plant protection by directly interfering with the growth of pathogens or by stimulating systemic resistance in their host. As rhizosphere-dwelling bacteria, these bacilli are surrounded and constantly interacting with other microbes via different types of communications. With this review, we provide an updated vision of the molecular and phenotypic responses of Bacillus upon sensing other rhizosphere microorganisms and/or their metabolites. We illustrate how Bacillus spp. may react by modulating the production of secondary metabolites, such as cyclic lipopeptides or polyketides. On the other hand, some developmental processes, such as biofilm formation, motility, and sporulation may also be modified upon interaction, reflecting the adaptation of Bacillus multicellular communities to microbial competitors for preserving their ecological persistence. This review also points out the limited data available and a global lack of knowledge indicating that more research is needed in order to, not only better understand the ecology of bacilli in their natural soil niche, but also to better assess and improve their promising biocontrol potential.
Léa Girard
added a research item
The taxonomic affiliation of Pseudomonas isolates is currently assessed by using the 16S rRNA gene, MultiLocus Sequence Analysis (MLSA), or whole genome sequencing. Therefore, microbiologists are facing an arduous choice, either using the universal marker, knowing that these affiliations could be inaccurate, or engaging in more laborious and costly approaches. The rpoD gene, like the 16S rRNA gene, is included in most MLSA procedures and has already been suggested for the rapid identification of certain groups of Pseudomonas. However, a comprehensive overview of the rpoD-based phylogenetic relationships within the Pseudomonas genus is lacking. In this study, we present the rpoD-based phylogeny of 217 type strains of Pseudomonas and defined a cutoff value of 98% nucleotide identity to differentiate strains at the species level. To validate this approach, we sequenced the rpoD of 145 environmental isolates and complemented this analysis with whole genome sequencing. The rpoD sequence allowed us to accurately assign Pseudomonas isolates to 20 known species and represents an excellent first diagnostic tool to identify new Pseudomonas species. Finally, rpoD amplicon sequencing appears as a reliable and low-cost alternative, particularly in the case of large environmental studies with hundreds or thousands of isolates.
Feyisara Eyiwumi Oni
added 2 research items
Pseudomonas cyclic lipopeptides (CLPs) are encoded non-ribosomally by biosynthetic gene clusters (BGCs) and possess diverse biological activities. In this study, we conducted chemical structure and BGC analyses with antimicrobial activity assays for two CLPs produced by Pseudomonas strains isolated from the cocoyam rhizosphere in Cameroon and Nigeria. LC-MS and NMR analyses showed that the Pseudomonas sp. COR52 and A2W4.9 produce pseudodesmin and viscosinamide, respectively. These CLPs belong to the Viscosin group characterized by a nonapeptidic moiety with a 7-membered macrocycle. Similar to other Viscosin-group CLPs, the initiatory non-ribosomal peptide synthetase (NRPS) gene of the viscosinamide BGC is situated remotely from the other two NRPS genes. In contrast, the pseudodesmin genes are all clustered in a single genomic locus. Nano-to micromolar levels of pseudodesmin and viscosinamide led to the hyphal distortion and/or disintegration of Rhizoctonia solani AG2-2 and Pythium myriotylum CMR1, whereas similar levels of White Line-Inducing Principle (WLIP), another member of the Viscosin group, resulted in complete lysis of both soil-borne phytopathogens. In addition to the identification of the biosynthetic genes of these two CLPs and the demonstration of their interaction with soil-borne pathogens, this study provides further insights regarding evolutionary divergence within the Viscosin group.
1D 1H NMR spectrum and the alpha region of a 1H-13C gHSQC spectrum of pseudodesmin A and viscosinamide A, isolated from Pseudomonas spp. COR52 and A2W4.9, respectively. Phylogenetic analyses of the TE domains extracted from the modules of pseudodesmin and viscosinamide gene clusters. 1H and 13C chemical shift values for pseudodesmin A and viscosinamide A.
Niels Geudens
added a research item
Pseudomonas isolates from tropical environments have been underexplored and may form an untapped reservoir of interesting secondary metabolites. In this study, we compared Pseudomonas and cyclic lipopeptide (CLP) diversity in the rhizosphere of a cocoyam root rot disease (CRRD) suppressive soil in Boteva, Cameroon with those from four conducive soils in Cameroon and Nigeria. Compared to other soils, Boteva andosols were characterized by high silt, organic matter, nitrogen and calcium. Besides, the cocoyam rhizosphere at Boteva was characterized by strains belonging mainly to the P. koreensis and P. putida (sub)groups, with representations in the P. fluorescens, P. chlororaphis, P. jessenii, and P. asplenii (sub)groups. In contrast, P. putida isolates were prominent in conducive soils. Regarding CLP diversity, Boteva was characterized by strains producing eleven different CLP types with cocoyamide A producers, belonging to the P. koreensis group, being the most abundant. However, putisolvin III‐V producers were the most dominant in the rhizosphere of conducive soils in both Cameroon and Nigeria. Furthermore, we elucidated the chemical structure of putisolvin derivatives ‐ putisolvin III‐V, and described its biosynthetic gene cluster. We show that high Pseudomonas and metabolic diversity may be driven by microbial competition which likely contributes to soil suppressiveness to CRRD. This article is protected by copyright. All rights reserved.
Niels Geudens
added an update
Research at the interface of chemistry and microbiology shows the power of interdisciplinary collaborations. It provides new insights into the mode of action of Pseudomonas lipopeptides by assessing the antimicrobial activity of 20 synthetic analogues, and paves the way for advanced biophysical studies.
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Léa Girard
added a research item
The draft genome sequence of Pseudomonas aeruginosa LMG 1272, isolated from mushroom, is reported here. This strain triggers formation of a precipitate (“white line”) when cocultured with Pseudomonas tolaasii . However, LMG 1272 lacks the capacity to produce a cyclic lipopeptide that is typically associated with white line formation, suggesting the involvement of a different diffusible factor.
Olumide Omoboye
added 2 research items
Pseudomonas species are metabolically robust with capacity to produce secondary metabolites including cyclic lipopeptides (CLPs). Herein we conducted chemical analysis of crude CLP extract from the cocoyam rhizosphere-derived biocontrol strain Pseudomonas sp. COW3. We performed in silico analyses on its whole genome, and conducted in vitro antagonistic assay using the strain and purified CLPs. Via LC-MS and NMR, we elucidated the structures of four novel members of the bananamide group, named bananamides D-G. Besides variability in fatty acid length, bananamides D-G differ from previously described bananamides A-C and MD-0066 by the presence of a serine and aspartic acid at position 6 and 2, respectively. In addition, bananamide G has valine instead of isoleucine at position 8. Kendrick mass defect (KMD) allowed the assignment of molecular formulae to bananamides D and E. We unraveled a non-ribosomal peptide synthetase cluster banA, banB and banC which encodes the novel bananamide derivatives. Furthermore, COW3 displayed antagonistic activity and mycophagy against Pythium myriotylum, while it mainly showed mycophagy on Magnaporthe oryzae. Purified bananamides D-G inhibited the growth of P. myriotylum and M. oryzae and caused hyphal distortion. Our study shows the complementarity of chemical analyses and genome mining in the discovery and elucidation of novel CLPs. In addition, structurally diverse bananamides differ in their antimicrobial activity.
Pseudomonas species are metabolically robust, with capacity to produce secondary metabolites including cyclic lipopeptides (CLPs). Herein we conducted a chemical analysis of a crude CLP extract from the cocoyam rhizosphere-derived biocontrol strain Pseudomonas sp. COW3. We performed in silico analyses on its whole genome, and conducted in vitro antagonistic assay using the strain and purified CLPs. Via LC-MS and NMR, we elucidated the structures of four novel members of the bananamide group, named bananamides D-G. Besides variability in fatty acid length, bananamides D-G differ from previously described bananamides A-C and MD-0066 by the presence of a serine and aspartic acid at position 6 and 2, respectively. In addition, bananamide G has valine instead of isoleucine at position 8. Kendrick mass defect (KMD) allowed the assignment of molecular formulae to bananamides D and E. We unraveled a non-ribosomal peptide synthetase cluster banA, banB and banC which encodes the novel bananamide derivatives. Furthermore, COW3 displayed antagonistic activity and mycophagy against Pythium myriotylum, while it mainly showed mycophagy on Pyricularia oryzae. Purified bananamides D-G inhibited the growth of P. myriotylum and P. oryzae and caused hyphal distortion. Our study shows the complementarity of chemical analyses and genome mining in the discovery and elucidation of novel CLPs. In addition, structurally diverse bananamides differ in their antimicrobial activity.
Feyisara Eyiwumi Oni
added a research item
Soil microbial diversity has long been considered to be a key indicator of soil quality and health. In a previous study, we showed that the rhizosphere of the tropical cocoyam tuber crop in Cameroon is rich in fluorescent Pseudomonas taxonomic diversity and is also a hotspot for the production cyclic lipopeptide (CLP) biomolecules. However, factors contributing to this striking diversity are unclear. This study aimed to elucidate the influence of soil characteristics on Pseudomonas taxonomic and CLP diversity in the rhizosphere of cocoyam. Physico-chemical analyses was conducted for soils obtained from five cocoyam fields in Cameroon and Nigeria. More so, we analyzed Pseudomonas isolates from these cocoyam fields; 138 isolates from andosols in Cameroon (Boteva, Ekona and Maumu villages) and 172 from alfisols and ultisols in Nigeria (Ado-Ekiti and Umudike). Taxonomic characterization was done using the rpoD housekeeping gene while the presence of CLP production and types were deciphered using the drop collapse test and HPLC-MS, respectively. Further, Nuclear Magnetic Resonance (NMR) was conducted on crude CLP extracts to fully characterize unique CLPs. Compared to other soils, soils from Boteva recorded higher organic carbon, N, Ca, ECEC and silt. With respect to Pseudomonas taxonomic diversity, our results showed that 50% of isolates obtained from Boteva belonged to the P. fluorescens complex while the rest were P. putida group isolates. In contrast, other locations mainly recorded the presence of P. putida isolates. For CLP types, Pseudomonas isolates from Boteva produced eleven structurally diverse CLPs including four novel ones while those from Ekona, Maumu, Ado-Ekiti and Umudike produced six, five, three and two CLPs, respectively. Put together, our study suggests that the presence of P. fluorescens complex isolates and specific CLP types are indicators of soil quality in the cocoyam rhizosphere.
Feyisara Eyiwumi Oni
added 2 research items
Cyclic lipopeptides are metabolites produced by non-ribosomal peptide synthetases (NRPSs) in various bacteria including Pseudomonas, Bacillus and Streptomyces spp. They are composed of a cyclic oligopeptide lactone ring linked to a fatty acid tail and can cause destruction of microbial membranes, leading to death of bacteria, fungi, oomycetes and viruses. We investigated the diversity of cyclic lipopeptides produced by fluorescent pseudomonads associated with the tropical cocoyam tuber crop. First, 138 Pseudomonas isolates were subjected to drop collapse screening for biosurfactant activity. Whole genome sequencing was done for unique CLP-producing strains based on swarming motility, HPLC-MS and Nuclear Magnetic Resonance (NMR) analyses. Genome mining was conducted using Antismash v4.0 while the RAST annotation pipeline and Geneious software were used for bioinformatic analyses. Results of drop collapse showed that 50% of strains analysed are potential CLP producers. Swarming and HPLC-MS analyses enabled the identification of unique CLP types. Using Antismash, putative NRPS gene clusters were identified and amino acid residues were predicted. Comparison of A domains with those of previously reported CLPs enabled the identification of twelve CLPs, five of which are novel. These results are in agreement with NMR analyses which was conducted for eleven CLPs including entolysin, lokisin, xantholysin, putisolvin, WLIP and cocoyamide A. Our findings reveal the complementarity of genome mining with NMR analyses for the discovery of cyclic lipopeptides. Our current studies focus on the biological activity of these diverse compounds and their ecological roles in the rhizosphere.
Beneficial Pseudomonas spp. produce an array of antimicrobial secondary metabolites such as cyclic lipopeptides (CLPs). We investigated the capacity of CLP-producing Pseudomonas strains and their crude CLP extracts to control rice blast caused by Magnaporthe oryzae, both in a direct manner and via induced systemic resistance (ISR). In planta biocontrol assays showed that lokisin-, white line inducing principle (WLIP)-, entolysin- and N3-producing strains successfully induced resistance to M. oryzae VT5M1. Furthermore, crude extracts of lokisin, WLIP and entolysin gave similar ISR results when tested in planta. In contrast, a xantholysin-producing strain and crude extracts of N3, xantholysin and orfamide did not induce resistance against the rice blast disease. The role of WLIP in triggering ISR was further confirmed by using WLIP-deficient mutants. The severity of rice blast disease was significantly reduced when M. oryzae spores were pre-treated with crude extracts of N3, lokisin, WLIP, entolysin or orfamide prior to inoculation. In vitro microscopic assays further revealed the capacity of crude N3, lokisin, WLIP, entolysin, xantholysin and orfamide to significantly inhibit appressoria formation by M. oryzae. In addition, the lokisin and WLIP biosynthetic gene clusters in the producing strains are described. In short, our study demonstrates the biological activity of structurally diverse CLPs in the control of the rice blast disease caused by M. oryzae. Furthermore, we provide insight into the non-ribosomal peptide synthetase genes encoding the WLIP and lokisin biosynthetic machineries..
Niels Geudens
added a research item
Cyclic lipodepsipeptides produced by Pseudomonas spp. (Ps-CLPs) are biosurfactants that constitute a diverse class of versatile bioactive natural compounds with promising application potential. While chemically diverse, they obey a common structural blue-print, allowing the definition of 14 distinct groups with multiple structurally homologous members. In addition to antibacterial and antifungal properties the reported activity profile of Ps-CLPs includes their effect on bacterial motility, biofilm formation, induced defense responses in plants, their insecticidal activity and anti-proliferation effects on human cancer cell-lines. To further validate their status of potential bioactive substances, we assessed the results of 775 biological tests on 51 Ps-CLPs available from literature. From this, a fragmented view emerges. Taken as a group, Ps-CLPs present a broad activity profile. However, reports on individual Ps-CLPs are often much more limited in the scope of organisms that are challenged or activities that are explored. As a result, our analysis shows that the available data is currently too sparse to allow biological function to be correlated to a particular group of Ps-CLPs. Consequently, certain generalizations that appear in literature with respect to the biological activities of Ps-CLPs should be nuanced. This notwithstanding, the data for the two most extensively studied Ps-CLPs does indicate they can display activities against various biological targets. As the discovery of novel Ps-CLPs accelerates, current challenges to complete and maintain a useful overview of biological activity are discussed.
Feyisara Eyiwumi Oni
added a research item
Cocoyam (Xanthosoma sagittifolium (L.)), an important tuber crop in the tropics, is severely affected by the cocoyam root rot disease (CRRD) caused by Pythium myriotylum. The white cocoyam genotype is very susceptible while the red cocoyam has some field tolerance to CRRD. Fluorescent Pseudomonas isolates obtained from the rhizosphere of healthy red and white cocoyams from three different fields in Cameroon were taxonomically characterized. The cocoyam rhizosphere was enriched with P. fluorescens complex and P. putida isolates independent of the plant genotype. LC‐MS and NMR analyses revealed that 50% of the Pseudomonas isolates produced cyclic lipopeptides (CLPs) including entolysin, lokisin, WLIP, putisolvin and xantholysin together with eight novel CLPs. In general, CLP types were linked to specific taxonomic groups within the fluorescent pseudomonads. Representative CLP‐producing bacteria showed effective control against CRRD while purified CLPs caused hyphal branching or hyphal leakage in P. myriotylum. The structure of cocoyamide A, a CLP which is predominantly produced by P. koreensis group isolates within the P. fluorescens complex is described. Compared to the white cocoyam, the red cocoyam rhizosphere appeared to support a more diverse CLP spectrum. It remains to be investigated whether this contributes to the field tolerance displayed by the red cocoyam. This article is protected by copyright. All rights reserved.
Feyisara Eyiwumi Oni
added an update
Principal Investigators:
Prof. Dr. ir. Monica Höfte (Ghent University, Belgium) - Project Coordinator
Prof. Dr. José Martins (Ghent University, Belgium)
Prof. René De Mot (Katholieke University Leuven, Belgium)
Prof. Barbara De Coninck (Katholieke University Leuven, Belgium)
Prof. Edwin De Pauw (University of Liège, Belgium)
Dr. Marc Ongena (Gembloux AgroBiotech - University of Liège, Belgium)
Assoc. Prof. Loïc Quinton (University of Liège, Belgium)
Prof. Heiko Heerklotz (University of Freiburg, Germany)
Funding: FNRS/FWO Excellence of Science (EOS) Programme
 
Feyisara Eyiwumi Oni
added a project goal
Employing chemical-biology approaches to decipher primary functions of secondary metabolites