Ralph Kissen
Background and activities
The year 2020 was the International Year of Plant Health. Although it was overshadowed by another health crisis plant health is an important issue that merits our attention, also beyond 2020. The UN Food and Agriculture Organization (FAO) estimates that “up to 40% of food crops are lost due to plant pests and diseases annually”. This causes severe economic losses in the agricultural sector and poses a serious threat to food security. Pathogens and pests do not only damage crop plants but also threaten wild plant species. In addition to these biotic factors plant health can be severely affected by abiotic stresses such as heat, drought, flooding, pollution, etc.
My research interests are directly related to plant health as I study mechanisms that are involved in plant resilience against biotic and abiotic stresses. I work mostly on the model plant Arabidopsis thaliana and focus on two aspects:
1. The glucosinolate-myrosinase system, a plant defence mechanism
Glucosinolates are a group of more than 150 plant specialized metabolites characteristic of Brassicaceae, which include Arabidopsis thaliana and crops such as oilseed rape, mustard, broccoli and cabbage. Myrosinases are enzymes that convert glucosinolates into biologically active compounds when plants are attacked by pathogens or wounded by pests. These compounds can be toxic to microbial pathogens and insect pests, or attract parasitoids of these pests (tritrophic interactions). In addition they give the characteristic flavour to these plants, and are beneficial for human health.
I have identified and characterized enzymes that are involved in the biosynthesis and conversion of glucosinolates, and studied for example how a change in glucosinolate-derived compounds affects the interaction between the plant, insect pests and parasitoids.
Lately, I have also been investigating if these glucosinolate-derived compounds can act as so-called damage-associated molecular patterns (DAMPs). DAMPs are molecules that are generated when a plant is damaged, trigger the plant innate immune system and thereby act as danger signals to the damaged plant (and potentially its yet undamaged neighbours). I am interested in finding out if glucosinolate-derived products can be perceived (directly or indirectly) by the plant, what the plant innate immune response that is then triggered looks like, and how this protects the plant against pathogens and insects.
2. Plants and trace metals
Trace metals can be toxic for both plants and humans (e.g. Cd, Hg), and heavy metal pollution is a big problem for water supplies and agriculture soils. But trace metals can also be essential for plants as enzyme cofactors (e.g. Fe, Zn, Mn) and when they are deficient in crops this can cause human malnutrition. In addition, it has been hypothesized that plants can use trace metals as a defence mechanism (the so-called “elemental defence hypothesis”) and some plant species, called heavy metal hyperaccumulators, possess the natural capacity to tolerate and accumulate very high concentrations of metals.
I am on one hand investigating in how far metals in plants can complement or interfere with the glucosinolate defence mechanism described above. On the other hand I am looking at biotechnological approaches to increase the capacity of yeast, diatoms and plants to accumulate and tolerate heavy metals. These improved hyperaccumulators could then be used to remove heavy metals from contaminated waters or soils, an approach known as bioremediation.
Scientific, academic and artistic work
Displaying a selection of activities. See all publications in the database
2020
- (2020) Assessment of oxidative stress response genes in Avicennia marina exposed to oil contamination - Polyphenol oxidase (PPOA) as biomarker. Biotechnology Reports. vol. 28.
- (2020) The Role of a Glucosinolate-Derived Nitrile in Plant Immune Responses. Frontiers in Plant Science. vol. 11.
2019
- (2019) The Myb like transcription factor Phosphorus Starvation Response (PtPSR) controls conditional P acquisition and remodeling in marine microalgae. New Phytologist. vol. 225 (6).
2018
- (2018) Accumulation of (Ag(I) by Saccharomyces cereviseae cells expressing plant metallothioneins. Cells. vol. 7 (12).
- (2018) Arabidopsis mutants impaired in glutathione biosynthesis exhibit higher sensitivity towards the glucosinolate hydrolysis product allyl-isothiocyanate. Scientific Reports. vol. 8 (1).
- (2018) Benzyl Cyanide Leads to Auxin-Like Effects Through the Action of Nitrilases in Arabidopsis thaliana. Frontiers in Plant Science. vol. 9.
2017
- (2017) Heavy Metal Accumulation by Saccharomyces cerevisiae Cells Armed with Metal Binding Hexapeptides Targeted to the Inner Face of the Plasma Membrane. Applied Microbiology and Biotechnology. vol. 101 (14).
- (2017) Anchoring plant metallothioneins to the inner face of the plasma membrane of Saccharomyces cerevisiae cells leads to heavy metal accumulation. PLOS ONE. vol. 12 (5).
- (2017) Glucosinolate-Derived Isothiocyanates Inhibit Arabidopsis Growth and the Potency Depends on their Side Chain Structure. International Journal of Molecular Sciences. vol. 18 (11).
2016
- (2016) Effect of growth temperature on glucosinolate profiles in Arabidopsis thaliana accessions. Phytochemistry. vol. 130.
- (2016) Allyl-isothiocyanate treatment induces a complex transcriptional reprogramming including heat stress, oxidative stress and plant defence responses in Arabidopsis thaliana. BMC Genomics. vol. 17.
2015
- (2015) Physiology and cellular mechanisms of isothiocyanates and other glucosinolate degradation products in plants. Frontiers in Plant Science.
2012
- (2012) Phytoalexins in defense against pathogens. Trends in Plant Science. vol. 17 (2).
- (2012) Ecotype dependent expression and alternative splicing of epithiospecifier protein (ESP) in Arabidopsis thaliana. Plant Molecular Biology. vol. 78 (4-5).
- (2012) Characterization of recombinant nitrile-specifier proteins (NSPs) of Arabidopsis thaliana: Dependency on Fe(II) ions and the effect of glucosinolate substrate and reaction conditions. Phytochemistry. vol. 84.
2010
- (2010) Transcriptional profiling of an Fd-GOGAT1/GLU1 mutant in Arabidopsis thaliana reveals a multiple stress response and extensive reprogramming of the transcriptome. BMC Genomics. vol. 11.
2009
- (2009) Nitrile-specifier proteins involved in glucosinolate hydrolysis in Arabidopsis thaliana. Journal of Biological Chemistry. vol. 284 (18).
- (2009) Modifying the alkylglucosinolate profile in Arabidopsis thaliana alters the tritrophic interaction with the herbivore Brevicoryne brassicae and parasitoid Diaeretiella rapae. Journal of Chemical Ecology. vol. 35 (8).
- (2009) The “mustard oil bomb”: not so easy to assemble?! Localization, expression and distribution of components of the myrosinase enzyme system. Phytochemistry Reviews. vol. 8 (1).
2008
- (2008) Characterization of novel nitrile specifier proteins (NSPs) involved in glucosinolate hydrolysis in Arabidopsis thaliana. Physiologia Plantarum : An International Journal for Plant Biology. vol. 133 (3).