Short presentation

Research area

Plants produce a multitude of complex metabolites to navigate their interaction with the environment, e.g. as defense compounds. Some of these compounds are used by humans for medicine, food supplements, color pigments etc, while others are important determinants of crop plants’ nutritional value for humans and fodder crops for animals. For a number of years I have been investigating the physiological roles and catabolism of cyanogenic glycosides, mainly using the crop plant sorghum as a model, but also Lotus japonicus, cassava, barley and almond. Cyanogenic glycosides serve important roles in plants as deterrents of attack from herbivores and microorganisms. However, they also serve other, less investigated, roles in plants, and most of my research has focused on elucidating these functions and the associated enzymatic pathways. This work has caused me to frequently discover atypical enzymatic functions, one of them a reductive cleavage reaction carried out by glutathione transferase enzymes (GSTs) in a pathway for recovery of nitrogen from cyanogenic glucosides. The enzyme family of GSTs is large and complex and with very few identified physiological functions. With a young investigator grant from the VILLUM Foundation my group focus on revealing other functions of GSTs in specialized metabolism.

Projects

• GSTspecial: Glutathione transferases in plant specialized metabolism. Identification of GST functions to shed light onto mysterious enzyme family and identify new tools for future pathway discovery.
• Physiological functions of cyanogenic glucosides and related compounds, in crop plants and model plants.
• Advancing mass spectrometry imaging for plant tissues

Web

• http://plantplasticity.ku.dk/research/metabolic/
• http://plen.ku.dk/english/research/plant_biochemistry/cgvsc/

Key technologies

• Mass spectrometry imaging
• Metabolomics; state-of-the-art LC-MS and GC-MS
• Transcriptomics
• Molecular cloning,  heterologous expression, in vitro enzyme assays
• Mutant plant characterization

Current funding

Co-PI of Semper Ardens grant from The Carlsberg Foundation, total 19 mill dkk

VILLUM Young Investigator grant, The VILLUM Foundation, Denmark, grant number 19151

Selected publications

1. Montini, L., Crocoll, C., Gleadow, R., Motawia, M.S., Janfelt, C. and Bjarnholt, N. (2020). Metabolite dynamics during sorghum grain germination visualised by MALDI-mass spectrometry imaging. Plant Physiol. 183 (3): 925-942.
2. Bjarnholt, N., Neilson, E.H., Crocoll, C., Nielsen, L.J., Jørgensen, K., Motawia, M.S., Olsen, C.E., Dixon, D.P., Edwards, R., Møller, B.L. (2018). Glutathione transferases catalyze recycling of auto-toxic cyanogenic glucosides in sorghum. Plant J. 94 (6): 1109-1125.
3. Mnich, E., Vanholme, R., Oyarce, P., Liu, S., Lu, F., Goeminne, G., Jørgensen, B., Motawie, M.S., Boerjan, W., Ralph, J., Ulvskov, P., Møller, B.L., Bjarnholt, N., Harholt, J. (2017). Degradation of lignin β-aryl ether units in Arabidopsis thaliana expressing LigD, LigF and LigG from Sphingomonas paucimobilis SYK-6. Plant Biotech. J. doi: 10.1111/pbi.12655
4. Nielsen, L. J., Stuart, P., Pičmanová, M., Rasmussen, S., Olsen, C. E., Harholt, J., Møller, B. L. & Bjarnholt, N. (2016). Dhurrin metabolism in the developing grain of Sorghum bicolor (L.) Moench investigated by metabolite profiling and novel clustering analyses of time-resolved transcriptomic data. BMC Genomics 17 (1): 1021 DOI: 10.1186/s12864-016-3360-4
5. Pičmanová, M. , Neilson, E.H., Motawia, M.S., Olsen, C.E. , Agerbirk, N., Gray, C.J., Flitsch, S., Meier, S., Silvestro, D., Jørgensen, K., Sánchez-Pérez, R., Møller, B.L., Bjarnholt, N. (2015). A recycling pathway for cyanogenic glycosides evidenced by the comparative metabolic profiling in three cyanogenic plant species. Biochem. J. 469 (3): 375-389 doi: 10.1042/BJ20150390
6. Bjarnholt, N., Li, B., D'Alvise, J., Janfelt, C. (2014). Mass spectrometry imaging of plant metabolites - principles and possibilities. Nat. Prod. Rep. 31 (6):818-837 doi: 
   10.1039/C3NP70100J
7. Li, B., Knudsen, C., Hansen, N.K., Jørgensen, K., Kannangara, R., Bak, S., Takos, A., Rook, F., Hansen, S.H., Møller, B.L., Janfelt, C., Bjarnholt, N. (2013). Visualizing metabolite distribution and enzymatic conversion in plant tissues by desorption electrospray ionization mass spectrometry imaging. Plant J. 74 (6): 1059-1071. doi: 10.1111/tpj.12183

CV

Education

Dec. 2007 PhD in Plant Biochemistry, University of Copenhagen, DK

Mar. 2003 MSc in Environmental Chemistry, University of Copenhagen, DK

Positions and research stays

2018-                                          Research group leader at Dept. of Plant and Environmental Sciences, UCPH, DK

2014-                                          Associate Professor at Dept. of Plant and Environmental Sciences, UCPH, DK

2008-2014       Postdoc at Dept. of Plant Biology and Biotechnology, UCPH, DK

2004-2007       PhD-student at Dept. of Plant Biology and Biotechnology, UCPH, DK

2004-2019         Short-term research stays: University of Queensland, Autralia; Durham University, United Kingdom; Danish Institute of Agricultural Sciences (DIAS) (now part of Aarhus University), Denmark; Reflab, Copenhagen University Hospital, Denmark

Scientific focus areas

• Plant Mass Spectrometry Imaging and other chemical analyses, metabolomics.
• Plant specialized metabolites.
• Glutathione transferase enzymes from plants, in basic science and crop science, detoxification.

Grants

2020                 Co-PI of Semper Ardens grant from The Carlsberg Foundation, total 19 mill dkk

2019                 DFF-ERC, 958.000 dkk, IRFD, grant no. 9126-00003B

2018                 VILLUM Young Investigator, 10 mill dkk, VILLUM Foundation, grant no. 19151

2016                 Rated A in phase 2 of the 2016 ERC StG call

2012                 Co-PI, VILLUM Research Centre “Plant Plasticity”, VILLUM Foundation, grant no. VKR023054

2009                 Co-applicant of five-year project, 13 mill dkk, IRFD, grant no. 0602–00999B

2008                 Personal postdoctoral Globalisation fellowship: two years awarded by UCPH

2004                 PhD scholarship, awarded by Royal Veterinary and Agricultural University

Management experience and institutional responsibilities

2020-               Member of the Copenhagen Plant Science Center scientific committee

2020                 Completed UCPH course: ‘Leading Research’

2019-                Member of departmental research committee

2018-                Research group leader, Plant Metabolic Plasticity Group

2016-                Member of metabolomics platform steering group

2009-2018 Coordinator of research topic: Endogenous turnover of cyanogenic glucosides

International collaborators

MSI:                  Professor Anders Meibom, University of Lausanne, Switzerland; Bruker Daltonics, Germany

Glutathione transferases, gene editing and crop science: Professor Robert Edwards, Newcastle University, UK; Professor Dean Riechers, University of Illinois, USA; Professor Ian Godwin, University of Queensland, Australia.

Plant-pathogen interactions:

Gerhard Adam, University of Natural Resources and Life Sciences (BOKU), Vienna, Austria

Supervision and teaching

PhD-students: Currently 4; Completed 6

Postdocs: Currently 1; Past 2

Teaching: B.Sc. level biochemistry, metabolomics, Mass Spectrometry Imaging

Selected conference presentations

2020     Plant Biology 2020, American Society of Plant Biology World summit. Online.

2019     Ourcon VII (global forum on mass spectrometry imaging), Saint-Malo, France.

2015     Invited talk: 250th ACS National Meeting, American Chemical Society, Boston, USA.

2012     Invited talk: Plant Biotech Denmark, Copenhagen, Denmark

2010     Banff Conference for Plant Metabolism, Banff, Canada