Resumen
Background and aims: Plant and bacteria are able to synthesise proline, which acts as a compound to counteract the negative effects of osmotic stresses. Most methodologies rely on the extraction of compounds using destructive methods. This work describes a new proline biosensor that allows the monitoring of proline levels in a non-invasive manner in root exudates and nodules of legume plants. Met ...
[++]
Background and aims: Plant and bacteria are able to synthesise proline, which acts as a compound to counteract the negative effects of osmotic stresses. Most methodologies rely on the extraction of compounds using destructive methods. This work describes a new proline biosensor that allows the monitoring of proline levels in a non-invasive manner in root exudates and nodules of legume plants. Methods: The proline biosensor was constructed by cloning the promoter region of pRL120553, a gene with high levels of induction in the presence of proline, in front of the lux cassette in Rhizobium leguminosarum bv. viciae. Results: Free-living assays show that the proline biosensor is sensitive and specific for proline. Proline was detected in both root exudates and nodules of pea plants. The luminescence detected in bacteroids did not show variations during osmotic stress treatments, but significantly increased during recovery. Conclusions: This biosensor is a useful tool for the in vivo monitoring of proline levels in root exudates and bacteroids of symbiotic root nodules, and it contributes to our understanding of the metabolic exchange occurring in nodules under abiotic stress conditions. [--]
Materias
Rhizosphere,
Proline dehydrogenase,
Water deficit,
Salt stress,
Rhizobium,
Symbiosis
Publicado en
Plant and Soil, 2020, 452, 413-422
Departamento
Universidad Pública de Navarra/Nafarroako Unibertsitate Publikoa. Institute for Multidisciplinary Research in Applied Biology - IMAB
Entidades Financiadoras
This work was supported by grants AGL2014-56561-P and RTI2018-09463-B-C22 (MCIU/AEI/FEDER, UE) and the Biotechnology and Biological Sciences Research Council [grant number BB/K001868/2]. M.I.R. received a predoctoral F.P.I. fellowship (BES-2012-059972) and a mobility grant (EEBB-C-15-00615) from the Spanish Ministry of Economy and Competitiveness. E.L. is a Ramón y Cajal fellow funded by the Spanish Ministry of Science and Innovation (grant RYC2018-023867-I).