Temperature-mediated biosynthesis of the phytotoxin phaseolotoxin by Pseudomonas syringae pv. phaseolicola depends on the autoregulated expression of the phtABC genes
Fecha
2017Autor
Versión
Acceso abierto / Sarbide irekia
Tipo
Artículo / Artikulua
Versión
Versión publicada / Argitaratu den bertsioa
Impacto
|
10.1371/journal.pone.0178441
Resumen
Pseudomonas syringae pv. phaseolicola produces phaseolotoxin in a temperature dependent
manner, being optimally synthesized between 18ºC and 20ºC, while no detectable
amounts are present above 28ºC. The Pht cluster, involved in the biosynthesis of phaseolotoxin,
contains 23 genes that are organized in five transcriptional units. The function of most
of the genes from the Pht cluster is still ...
[++]
Pseudomonas syringae pv. phaseolicola produces phaseolotoxin in a temperature dependent
manner, being optimally synthesized between 18ºC and 20ºC, while no detectable
amounts are present above 28ºC. The Pht cluster, involved in the biosynthesis of phaseolotoxin,
contains 23 genes that are organized in five transcriptional units. The function of most
of the genes from the Pht cluster is still unknown and little information about the regulatory
circuitry leading to expression of these genes has been reported. The purpose of the present
study was to investigate the participation of pht genes in the regulation of the operons
coded into the Pht cluster. We conducted Northern blot, uidA fusions and reverse transcription-
PCR assays of pht genes in several mutants unable to produce phaseolotoxin. This
allowed us to determine that, in P. syringae pv. phaseolicola NPS3121, genes phtABC are
essential to prevent their own expression at 28ºC, a temperature at which no detectable
amounts of the toxin are present. We obtained evidence that the phtABC genes also participate
in the regulation of the phtD, phtM and phtL operons. According to our results, we propose
that PhtABC and other Pht product activities could be involved in the synthesis of the
sulfodiaminophosphinyl moiety of phaseolotoxin, which indirectly could be involved in the
transcriptional regulation of the phtA operon. [--]
Materias
Pseudomonas syringae pv. Phaseolicola,
Phaseolotoxin,
Pht cluster,
phtABC genes
Editor
Public Library of Science
Publicado en
Plos One, 12(6): e0178441
Departamento
Universidad Pública de Navarra. Departamento de Producción Agraria /
Nafarroako Unibertsitate Publikoa. Nekazaritza Ekoizpena Saila
Versión del editor
Entidades Financiadoras
This work was funded by grants from the Consejo Nacional de Ciencia y Tecnología (CONACyT), research grant CB-2015-01-255155 to SA, and from the Spanish Plan Nacional I + D + i grant AGL2014-53242-C2-2-R, from the Ministerio de Economía y Competitividad, co-financed by the Fondo Europeo de Desarrollo Regional (FEDER) to JM.