title: Non-ribosomal Peptide Synthases from Pseudomonas aeruginosa Play a Role in Cyclodipeptide Biosynthesis, Quorum-Sensing Regulation, and Root Development in a Plant Host.
abstract: Diverse molecules mediate cross-kingdom communication between bacteria and their eukaryotic partners and determine pathogenic or symbiotic relationships. N-acyl-L-homoserine lactone-dependent quorum-sensing signaling represses the biosynthesis of bacterial cyclodipeptides (CDPs) that act as auxin signal mimics in the host plant Arabidopsis thaliana. In this work, we performed bioinformatics, biochemical, and plant growth analyses to identify non-ribosomal peptide synthase (NRPS) proteins of Pseudomonas aeruginosa, which are involved in CDP synthesis. A reverse genetics strategy allowed the identification of the genes encoding putative multi-modular-NRPS (MM-NRPS). Mutations in these genes affected the synthesis of the CDPs cyclo(L-Pro-L-Val), cyclo(L-Pro-L-Leu), and cyclo(L-Pro-L-Tyr), while showing wild-type-like levels of virulence factors, such as violacein, elastase, and pyocyanin. When analyzing the bioactivity of purified, naturally produced CDPs, it was found that cyclo(L-Pro-L-Tyr) and cyclo(L-Pro-L-Val) were capable of antagonizing quorum-sensing-LasR (QS-LasR)-dependent signaling in a contrasting manner in the cell-free supernatants of the selected NRPS mutants, which showed QS induction. Using a bacteria-plant interaction system, we further show that the pvdJ, ambB, and pchE P. aeruginosa mutants failed to repress primary root growth, but improved root branching in A. thaliana seedlings. These results indicated that the CDP production in P. aeruginosa depended on the functional MM-NRPS, which influences quorum-sensing of bacteria and plays a role in root architecture remodeling.
authors.affiliation: Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Edif. B-3, Ciudad Universitaria, 58030, Morelia, Michoacán, México.
authors.forename: Omar
authors.initials: O
authors.lastname: González
authors.affiliation: Laboratorio de Biología del Desarrollo Vegetal, Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Edif. A1´, Ciudad Universitaria, 58030, Morelia, Michoacán, México.|Instituto de Ecología A.C., Xalapa, Ver., México.
authors.forename: Randy
authors.initials: R
authors.lastname: Ortíz-Castro
authors.affiliation: Depto. Ingeniería Agroindustrial, División de Ciencias de la Salud e Ingenierías, Universidad de Guanajuato, Salvatierra, Gto., México.
authors.forename: César
authors.initials: C
authors.lastname: Díaz-Pérez
authors.affiliation: Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Edif. B-3, Ciudad Universitaria, 58030, Morelia, Michoacán, México.
authors.forename: Alma L
authors.initials: AL
authors.lastname: Díaz-Pérez
authors.affiliation: Laboratorio de Biología del Desarrollo Vegetal, Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Edif. A1´, Ciudad Universitaria, 58030, Morelia, Michoacán, México.
authors.forename: Viridiana
authors.initials: V
authors.lastname: Magaña-Dueñas
authors.affiliation: Laboratorio de Biología del Desarrollo Vegetal, Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Edif. A1´, Ciudad Universitaria, 58030, Morelia, Michoacán, México.
authors.forename: José
authors.initials: J
authors.lastname: López-Bucio
authors.affiliation: Laboratorio de Biotecnología Microbiana, Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Edif. B-3, Ciudad Universitaria, 58030, Morelia, Michoacán, México. jcgarcia@umich.mx.
authors.forename: Jesús
authors.initials: J
authors.lastname: Campos-García
mesh_terms: D017360:Arabidopsis / Q000382:microbiology*; D004151:Dipeptides / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D007210:Indoleacetic Acids / Q000378:metabolism; D007211:Indoles / Q000378:metabolism; D046908:Peptide Biosynthesis, Nucleic Acid-Independent / Q000235:genetics*; D010456:Peptides, Cyclic / Q000235:genetics / Q000378:metabolism*; D010879:Piperazines / Q000378:metabolism*; D018517:Plant Roots / Q000196:embryology*; D011550:Pseudomonas aeruginosa / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D011710:Pyocyanine / Q000378:metabolism; D053038:Quorum Sensing / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction; D037521:Virulence Factors / Q000378:metabolism
chemical_list: D004151:Dipeptides; D007210:Indoleacetic Acids; D007211:Indoles; D010456:Peptides, Cyclic; D010879:Piperazines; D037521:Virulence Factors; C424926:cyclo(prolyl-valyl); C085319:maculosin; D011710:Pyocyanine; C063155:violacein
keywords: Cyclodipeptides; Non-ribosomal peptide synthases; Plant-growth promotion; Pseudomonas aeruginosa; Quorum-sensing; Siderophores