ORCID Profile
0000-0003-3394-0296
Current Organisation
Ghent University
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Publisher: American Chemical Society (ACS)
Date: 07-02-2020
Publisher: Proceedings of the National Academy of Sciences
Date: 12-01-2023
Abstract: Rhizogenic Agrobacterium strains comprise biotrophic pathogens that cause hairy root disease (HRD) on hydroponically grown Solanaceae and Cucurbitaceae crops, besides being widely explored agents for the creation of hairy root cultures for the sustainable production of plant-specialized metabolites. Hairy root formation is mediated through the expression of genes encoded on the T-DNA of the root-inducing (Ri) plasmid, of which several, including root oncogenic locus B ( rolB ), play a major role in hairy root development. Despite decades of research, the exact molecular function of the proteins encoded by the rol genes remains enigmatic. Here, by means of TurboID-mediated proximity labeling in tomato ( Solanum lycopersicum) hairy roots, we identified the repressor proteins TOPLESS (TPL) and Novel Interactor of JAZ (NINJA) as direct interactors of RolB. Although these interactions allow RolB to act as a transcriptional repressor, our data hint at another in planta function of the RolB oncoprotein. Hence, by a series of plant bioassays, transcriptomic and DNA-binding site enrichment analyses, we conclude that RolB can mitigate the TPL functioning so that it leads to a specific and partial reprogramming of phytohormone signaling, immunity, growth, and developmental processes. Our data support a model in which RolB manipulates host transcription, at least in part, through interaction with TPL, to facilitate hairy root development. Thereby, we provide important mechanistic insights into this renowned oncoprotein in HRD.
Publisher: Elsevier BV
Date: 07-2019
DOI: 10.1016/J.PHYTOCHEM.2019.03.018
Abstract: Diatoms are abundant unicellular marine photosynthetic algae that have genetically ersified their physiology and metabolism while adapting to numerous environments. The metabolic repertoire of diatoms presents opportunities to characterise the biosynthesis and production of new and potentially valuable microalgal compounds, including sterols. Sterols of plant origin, known as phytosterols, have been studied for health benefits including demonstrated cholesterol-lowering properties. In this review we summarise sterol ersity, the unique metabolic features of sterol biosynthesis in diatoms, and prospects for the extraction of diatom phytosterols in comparison to existing sources. We also review biotechnological efforts to manipulate diatom biosynthesis, including culture conditions and avenues for the rational engineering of metabolism and cellular regulation.
Publisher: University of Liege
Date: 2018
Abstract: Description of the subject. In recent years, biological methodologies, such as solid-state fermentation, have acquired a great relevance for bioremediation of complex molecules because of their efficiency and low environmental impact. Specifically, the use of white-rot fungi in different biotechnological processes has emerged as a promising strategy given their broad enzymatic potential. Objectives. Evaluation of three in idual fungal species, as well as various fungal consortia of these species, for the degradation of a mixture of dyes, brilliant blue – allura red, through solid-state fermentation. Method. The species Pleurotus pulmonarius, Pleurotus ostreatus and Trametes versicolor were assessed, both in idually, and in their binary consortia. The interaction between the mycelia of the different white-rot fungi was taken into account as a criterion for using their consortia to degrade the mixture of pollutants under solid conditions. The dyes were adsorbed onto the agro-industrial by-products flower stems and corncob. The fermentative process was carried out over 20 days, after which the degradation percentage was quantified by UV-Vis spectroscopy. Results. The highest degradation percentage was obtained after fermentation by T. versicolor alone. This species reached an average degradation of 79.57% of the binary mixture of dyes, brilliant blue – allura red. Meanwhile, the best consortium, composed of P. ostreatus and T. versicolor, achieved a degradation of 63.24%. Conclusions. These results suggest that the use of fungal consortia, in solid media, does not always lead to a synergy between species for improved dye degradation by the integrated strategy that includes the processes of adsorption and solid-state fermentation. Instead, competition for space and nutrients associated with growth on a solid substrate could decrease the degradation efficiency.
Publisher: Springer Science and Business Media LLC
Date: 07-07-2020
Publisher: Elsevier BV
Date: 06-2020
Publisher: Elsevier BV
Date: 02-2022
Publisher: MDPI AG
Date: 21-12-2020
DOI: 10.3390/PH13120481
Abstract: Sterols are a class of triterpenoid molecules with erse functional roles in eukaryotic cells, including intracellular signaling and regulation of cell membrane fluidity. Diatoms are a dominant eukaryotic phytoplankton group that produce a wide ersity of sterol compounds. The enzymes 3-hydroxy-3-methyl glutaryl CoA reductase (HMGR) and squalene epoxidase (SQE) have been reported to be rate-limiting steps in sterol biosynthesis in other model eukaryotes however, the extent to which these enzymes regulate triterpenoid production in diatoms is not known. To probe the role of these two metabolic nodes in the regulation of sterol metabolic flux in diatoms, we independently over-expressed two versions of the native HMGR and a conventional, heterologous SQE gene in the diatoms Thalassiosira pseudonana and Phaeodactylum tricornutum. Overexpression of these key enzymes resulted in significant differential accumulation of downstream sterol pathway intermediates in P. tricornutum. HMGR-mVenus overexpression resulted in the accumulation of squalene, cycloartenol, and obtusifoliol, while cycloartenol and obtusifoliol accumulated in response to heterologous NoSQE-mVenus overexpression. In addition, accumulation of the end-point sterol 24-methylenecholesta-5,24(24’)-dien-3β-ol was observed in all P. tricornutum overexpression lines, and c esterol increased three-fold in P. tricornutum lines expressing NoSQE-mVenus. Minor differences in end-point sterol composition were also found in T. pseudonana, but no accumulation of sterol pathway intermediates was observed. Despite the successful manipulation of pathway intermediates and in idual sterols in P. tricornutum, total sterol levels did not change significantly in transformed lines, suggesting the existence of tight pathway regulation to maintain total sterol content.
Publisher: MDPI AG
Date: 02-2020
DOI: 10.3390/JMSE8020085
Abstract: Diatoms are a broadly distributed and evolutionarily ersified group of microalgae that produce a erse range of sterol compounds. Sterols are triterpenoids that play essential roles in membrane-related processes in eukaryotic cells. Some sterol compounds possess bioactivities that promote human health and are currently used as nutraceuticals. The relationship between sterol ersity in diatoms and their acclimation to different environments is not well understood. In this study, we investigated the occurrence of different sterol types across twelve diatom species, as well as the effect of temperature reduction and changes in salinity on the sterol contents of three model diatom species. In the diatoms Thalassiosira pseudonana, Phaeodactylum tricornutum and Chaetoceros muelleri, we found that changes in the relative contents of minor sterols accompanied shifts in temperature and salinity. This may be indicative of acquired adaptive traits in diatom metabolism.
Publisher: Cold Spring Harbor Laboratory
Date: 30-07-2020
DOI: 10.1101/2020.07.30.228171
Abstract: Sterols are a class of triterpenoid molecules with erse functional roles in eukaryotic cells, including intracellular signaling and regulation of cell membrane fluidity. Diatoms are a dominant eukaryotic phytoplankton group that produce a wide ersity of sterol compounds. The enzymes 3-hydroxy-3-methyl glutaryl CoA reductase ( HMGR ) and squalene epoxidase (SQE) have been reported to be rate-limiting steps in sterol biosynthesis in other model eukaryotes however, the extent to which these enzymes regulate triterpenoid production in diatoms is not known. To probe the role of these two metabolic nodes in the regulation of sterol metabolic flux in diatoms, we independently over-expressed two versions of the native HMGR and a conventional, heterologous SQE gene in the diatoms Thalassiosira pseudonana and Phaeodactylum tricornutum . Overexpression of these key enzymes resulted in significant differential accumulation of downstream sterol pathway intermediates in P. tricornutum . HMGR-mVenus overexpression resulted in the accumulation of squalene, cycloartenol, and obtusifoliol, while cycloartenol and obtusifoliol accumulated in response to heterologous NoSQE-mVenus overexpression. In addition, accumulation of the end-point sterol 24-methylenecholesta-5,24(24’)-dien-3β-ol was observed in all P. tricornutum overexpression lines, and c esterol increased 3-fold in P. tricornutum lines expressing NoSQE-mVenus. Minor differences in end-point sterol composition were also found in T. pseudonana , but no accumulation of sterol pathway intermediates was observed. Despite the successful manipulation of pathway intermediates and in idual sterols in P. tricornutum , total sterol levels did not change significantly in transformed lines, suggesting the existence of tight pathway regulation to maintain total sterol content.
Publisher: Springer Science and Business Media LLC
Date: 17-05-2017
No related grants have been discovered for Ana Cristina Jaramillo Madrid.