Jørgen Leisner

Short presentation

I am a biologist by education that have specialized in food microbiology. My research areas are:

•Chitinases and chitin binding proteins as virulence factors for food-borne bacterial pathogens. Traditionally these enzymes and proteins have been viewed as tools for bacterial survival in the environment due to the ubiquitous distribution of chitin.

•The importance of bacterial metabolism for the sensory quality of food products. I am in particular looking at lactic acid bacteria as potential spoilage organisms.

•Antibiotic resistance as a tool for bacterial survival. The hypothesis is that antibiotic resistance is of importance in relation to nutrition bottlenecks during the stationary growth phase.

•I also work on other aspects of food microbiology e.g. in relation to monitoring presence of bacterial pathogens during food processing as well as the application of bacteriocins (antimicrobial peptides) produced by lactic acid bacteria for biopreservation of foods.

 I accept bachelor and master students in all of the areas above.

CV

Curriculum vitae

Associate Professor Jørgen Leisner, M.Sc. Ph.D.

Academic Degrees

- M.Sc . (1987), Århus University, Århus, Denmark.

- Ph.D. (1992) Royal Veterinary and Agricultural University, Copenhagen, Denmark.

Career path:

- 1999-present Associate Professor at the Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen, Denmark.

- 2008 Sabbatical at the Carlsberg Laboratory, Copenhagen, Denmark

- 1996-1999 Assistant Professor at the Department of Veterinary Disease Biology, Faculty of Life Sciences, University of Copenhagen.

- 1995-1996 Universiti Putra Malaysia. Postdoctoral work

- 1992-1995 University of Alberta (Canada). Postdoctoral work

- 1989-1992 Royal Veterinary and Agricultural University. Doctoral work

Research focus areas:

- Molecular ecology and pathogenesis of food-borne bacterial pathogens

Main focus is on importance of Listeria monocytogenes and Salmonella virulence factors (especially chitinases and chitin binding proteins) for pathogenesis in the vertebrate host. We use mammalian and non-mammalian model organisms for this research, including Dictyostelium and the fruit fly Drosophila melanogaster. We are also interested in elucidating parameters of importance for survival of bacterial pathogens in the stationary phase of growth.

- Importance of lactic acid bacteria for quality and safety of minimal processed foods

Main focus is on the genus Carnobacterium in relation to meat and fish products.

Scientific production: 40 peer reviewed papers in international journals and 34 abstract contributions at national and international meetings.

Research management and fund raising: Project leader or co-leader in four externally financed projects since 2003:

- 2003-2004: Carnobacterium - taxonomy and metabolic activity of species and sub-species involved in spoilage of fish and meat products. DKK 1,652,186 from the Danish Research Council for Agricultural Research.

- 2003-2004: Suboptimal conditions for growth of S. aureus. DKK 1,500,000 from the Danish Bacon and Meat Council.

- 2005-2006: Biogenic amines as a quality index for lightly preserved meat. DKK 1,500,000 from the Danish Bacon and Meat Council.

- 2009-2018: Salmonella chitinase activity. One two year post-doctoral fellowship from LIFE, University of Copenhagen (1,200,000 DKK , 2009-2011), one mobility Ph.D. student grant from the Danish Research Council for technology and innovation (DKK 2,400,000. 2011-2013) and one Ph.D. student supported by a faculty grant.

Publications since 2007 (h-factor=16) International peer reviewed journals and book chapters:

1. R.F. Frederiksen, J.J. Leisner 2015. Effects of Listeria monocytogenes EGD-e and Salmonella enterica ser. Typhimurium LT2 chitinases on intracellular survival in Dictyostelium discoideum and mammalian cell lines. FEMS Microbiology Letters 362, fnv067

2. R.F. Frederiksen, Y. Yoshimura, B.G. Storgaard, D.K. Paspaliari, B.O. Petersen, K. Chen, T. Larsen, J.Ø. Duus, H. Ingmer, N.V. Bovin, U. Westerlind, O. Blixt, M.M. Palcic, J.J. Leisner 2015. A diverse range of bacterial and eukaryotic chitinases hydrolyzes the LacNAc (Galbeta1,4GlcNAc) and LacdiNAc (GalNAcbeta1,4GlcNAc) motifs found on vertebrate and insect cells. Journal of Biological Chemistry 290, 5354-5366.

3. J.J. Leisner, T.B. Lund, E.A. Frandsen, N.B.E. Andersen, L. Fredslund, V.P.T. Nguyen, T. Kristiansen 2014. What consumers expect from food control and what they get - A case study of the microbial quality of sushi bars in Denmark. Food Control 45, 76-80.

4. T, Larsen, Y. Yoshimura, B.G.R. Voldborg, G. Cazzamali, N.V. Bovin, U. westerlind, M.M. Palcic, J.J. Leisner 2014. Human chitotriosidase cross reacts with mammalian-like substrates. FEBS Letters 588, 746-751.

5. I. Frans, K. Dierckens, S. Crauwels, A van Assche, J. Leisner, M.H. Larsen, C.W. Michiels, K.A. Willems, B. Lievens, P. Bossier, H. Rediers 2013. Does virulence assessment of Vibrio anguillarum using sea bass (Dicentrarchus labrax) larvae correspond with genotypic and phenotypic characterization? PLoS ONE 8, e70477.

6. R.F. Frederiksen, D.K. Paspaliari, T. Larsen, B.G. Storgaard, M.H. Larsen, H. Ingmer, M.M. Palcic and J.J. Leisner* 2013. Bacterial chitinases and chitin-binding protein as virulence factors. Microbiology 159, 833-847.

7. C. Cailliez-Grimal, S. Chaillou, J. Anba-Mondoloni, V. Loux, M.I. Afzal, A. Rahman, G. Kergourlay, M.-C. Champomier-Vergès, M. Zagorecb, P. Dalgaard, J. J. Leisner, H. Prévost, A.-M. Revol-Junelles, F. Borges 2013. Complete chromosome sequence of Carnobacterium maltaromaticum LMA 28. Genome Announcements 1, e00115-12.

8. J.J. Leisner*, J. Haaber 2012. Intraguild predation provides a selection mechanism for bacterial antagonistic compounds. Proceedings of the Royal Society B 279, 4513-4521.

9. J.J. Leisner ^*, M.A. Hansen, M.H. Larsen, L. Hansen, H. Ingmer and S.J. Sørensen 2012. The genome sequence of the lactic acid bacterium, Carnobacterium maltaromaticum ATCC 35586 encode potential virulence factors. International Journal of Food Microbiology 152, 107-115.

10. T. Larsen, B.O. Petersen, B.G. Storgaard J.Ø. Duus, M.M. Palcic, J.J. Leisner* 2011. Characterization of a novel Salmonella Typhimurium chitinase which hydrolyzes chitin, chitooligosaccharides and N-acetyllactoasamine-conjugates. Glycobiology 21, 426-436.

11. M.H. Larsen, J.J. Leisner and H. Ingmer* 2010. Listeria monocytogenes EGD chitinolytic activity is regulated by carbohydrates but also by the virulence regulator, PrfA. Applied and Environmental Microbiology 76, 6470-6476.

12. K.J. Kjeldgaard, M.L. Stormly, J.J. Leisner* 2010. Relation between microbial levels of ready-to-eat foods and the monitoring of compliance with HACCP-based own control programs in small Danish food outlets. Food Control 21, 1453-1457.

13. J.J. Leisner*, M.H. Larsen, H. Ingmer, B.O. Petersen, J.Ø. Duus and M.M. Palcic 2009. Cloning and comparison of phylogenetically related chitinases from Listeria monocytogenes EGD and Enterococcus faecalis V583. Journal of Applied Microbiology 107, 2080-2087.

14. J.J. Leisner and M. Vancanneyt 2009. Genus Paralactobacillus. In: Bergey's Manual of Systematic Bacteriology, vol. 3, 511-513.

15. S. Stolzenbach, J.J. Leisner, D.V. Byrne* 2009. Sensory shelf life determination of a processed meat product "rullepølse" and microbial metabolites as potential indicators. Meat Science 83, 285-292.

16. B.G. Laursen, D.V. Byrne, J.B. Kirkegaard, J.J. Leisner* 2009. Lactic acid bacteria associated with a heat-processing pork product and sources of variation affecting chemical indices of spoilage and sensory characteristics. Journal of Applied Microbiology 106, 543-553.

17. J.J. Leisner ^*, M.H. Larsen, R.L. Jørgensen, L. Brøndsted, L.E. Thomsen and H. Ingmer 2008. Chitin hydrolysis by Listeria spp. including L. monocytogenes. Applied and Environmental Microbiology 74, 3823-3830

18. J.J. Leisner ^*, F.K. Vogensen, J. Kollmann, B. Aideh, P. Vandamme, M. Vancanneyt and H. Ingmer 2008. a-Chitinase activity among lactic acid bacteria. Systematic and Applied Microbiology 31, 151-156.

19. J.J. Leisner*, B.G. Laursen, H. Prévost, D. Drider and P. Dalgaard 2007. Carnobacterium: positive and negative effects in the environment and in foods. FEMS Microbiology Reviews 31, 592-613.

20. M. Danielsen*, A. Wind, J.J. Leisner and M. Arpi 2007. Antimicrobial susceptibility of human blood culture isolates of Lactobacillus spp. European Journal of Clinical Microbiology and Infectious Disesases 26, 287-289.

21. R.L. Jensen, K.S. Pedersen, V. Loeschcke, H. Ingmer and J.J. Leisner* 2007. Limitations in the use of Drosophila melanogaster as a model host for Gram positive bacterial infection. Letters in Applied Microbiology 44, 218-223.

22. L. Bay, J.L Larsen and J.J. Leisner* 2007. Distribution of three genes involved in the pJM1 iron sequestering system in various Vibrio anguillarum serogroups. Systematic and Applied Microbiology 30, 85-92

*Corresponding author