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Lojkowska, E.

Publications and source records attributed to Lojkowska, E..

2 recordsLinked to original sources

Metabolic modeling of Pectobacterium parmentieri SCC3193 provides insights into metabolic pathways of plant pathogenic bacteria

Understanding the plant-microbe interactions are crucial for improving plant productivity and plant protection. The latter aspect is particularly relevant for sustainable agriculture and development of new preventive strategies against the spread of plant diseases. Constraint-based metabolic modeling is providing one of the possible ways to investigate the adaptation to different ecological niches and may give insights into the metabolic versatility of plant pathogenic bacteria. In this study, we present a curated metabolic model of the emerging plant pathogenic bacterium Pectobacterium parmentieri SCC3193. Using flux balance analysis (FBA), we predict the metabolic adaptation to two different ecological niches, relevant for the persistence and the plant colonization by this bacterium: soil and rhizosphere. We performed in silico gene deletions to predict the set of core essential genes for this bacterium to grow in such environments. We anticipate that our metabolic model will be a valuable element for defining a set of metabolic targets to control infection and spreading of this plant pathogen and a scaffold to interpret future -omics datasets for this bacterium.

systems biology

Scopoletin 8-hydroxylase: a novel enzyme involved in coumarin biosynthesis and iron-deficiency responses in Arabidopsis

HighlightA strongly iron-responsive gene of previously unknown function, At3g12900, encodes a scopoletin 8-hydroxylase involved in coumarin biosynthesis and plays an important role in the iron uptake strategy in Arabidopsis.\n\nAbstractIron (Fe) deficiency represents a serious agricultural problem, particularly in alkaline soils. Secretion of coumarins by Arabidopsis thaliana roots is induced under Fe-deficiency. An essential enzyme for the biosynthesis of major Arabidopsis coumarins, scopoletin and its derivatives, is Feruloyl-CoA 6-Hydroxylase1 (F6'H1) that belongs to a large enzyme family of the 2-oxoglutarate and Fe(II)-dependent dioxygenases. Another member of this family that is a close homologue of F6H1 and is encoded by a strongly Fe-responsive gene, At3g12900, is functionally characterized in the presented work. We purified the At3g12900 protein heterologously expressed in Escherichia coli and demonstrated that it is involved in the conversion of scopoletin into fraxetin via hydroxylation at the C8-position. Consequently, it was named scopoletin 8-hydroxylase (S8H). Its function in plant cells was confirmed by the transient expression of S8H protein in Nicotiana benthamiana leaves followed by the metabolite profiling and the biochemical and ionomic characterization of Arabidopsis s8h knockout lines grown under various regimes of Fe availability. Our results indicate that S8H is involved in coumarin biosynthesis as part of the Fe acquisition machinery.

plant biology