GMOs & Wine Media Round Table Cape Town, 25 June 2008

1. GMOs & Wine Media Round TableCape Town, 25 June 2008 GM Yeast in the wine industry Threat or opportunity? Florian F. Bauer Institute for Wine Biotechnology Department of Viticulture and Oenology Stellenbosch University

2. Wine and technology?

3. Wine and technology? • Consumer (our) expectations… • Good aroma and taste: Wine should be of consistently high quality • …at an affordable price • Be healthy: Needs to satisfy WHO and specific national criteria with regard to health regulations • Without damaging the environment: Production needs to limit environmental impact • and a highly competitive global market = Need for technological innovation

4. Why Yeast? The scientific case… • What is “Yeast”?  White powder? Baking tool?  Converts sugar into alcohol? • Unicellular organism - 1st biotechnological application (at least 6 KY B.C. ) • S. cerevisiae 1st microorganism seen under microscope • 1st eukaryotic genome to be sequenced (1996) • 1st to be used for the production of pharmaceuticals using recombinant DNA technology

5. Why Yeast? The scientific case… • One of the most studied organisms (next to Homo sapiens) • Well understood (≠ Homo sapiens): Best annotated genome • Accumulated knowledge and technological know-how • “Model system” • Nobel prizes in medicine • Scientific potential • All biotechnological tools • Understanding of genetic and biochemical networks (omics) • Understanding the consequences of modifications (traditional selection and genetic engineering) • Tools for monitoring of modifications

6. Why Yeast? The economic case… • Saccharomyces cerevisiae produces the four leading fermentation products (tons/year) worldwide • Baking • Brewing • Wine fermentation • Single cell proteins • The yeast strain determines essential characteristics of the final product • Nutritional value • Aroma • Flavour • Other applications: • Pharmaceuticals • Fine chemicals • Bio-ethanol • Pressing need for new yeast strains • Increasing competition between yeast manufacturers • 150 – 200 Rand/kg of speciality yeast vs 10 Rand/kg for baker’s yeast • New consumer demands • Environmentally friendly production practices • Health-related characteristics of the fermentation products

7. Yeast - science and application Scientifically best understood eukaryotic organism + Most used microorganisms in food and other biological production processes = innovation potential

8. Yeast and wine • Commercial starter cultures inoculated after pressing of grapes • More than 200 commercial strains • Differences in • Processing properties • Organoleptic properties of the wine • Many yeast-related aspects of wine making can be improved • The molecular nature of many of these traits is understood - - - but many can only be improved through GM

9. The ML01 application • Application made by Dr HJJ van Vuuren, Director: Wine Research Centre University of British Columbia Vancouver, Canada • Object of application: • Malolactic yeast ML01 • Already approved for use by FDA (USA) and Health Canada • What does it do? • What is malolactic fermentation (MLF)? • Carried out after alcoholic fermentation by lactic acid bacteria • Malolactic fermentation is essential in most red and many white wines for microbiological stabilisation and wine quality.

10. COOH COOH CH Malolactic enzyme 2 HOCH + +2 (NAD , Mn ) HOCH CH 3 COOH L- malic acid L- lactic acid + CO 2 MALOLACTIC FERMENTATION • Malolactic fermentation • Three reasons for MLF: • Lowering of acidity (deacidification) • Aroma compounds • Microbiological stability • Commercial starter cultures: Oenococcus oeni • Tolerant to lower pH, Ethanol, SO2 • Low temperatures

11. The malolactic yeast ML01 • Contains two trans-genes that encode • A malic acid transporter (from Schizosaccharomyces pombe) • A malolactic enzyme (from Oenococcus oeni) • Efficiently converts malate to lactate during alcoholic fermentation

12. Advantages - Disadvantages + • Reduced processing time • Reduced risk of spoilage • Reduced health risks - ? • Changes to the aroma and flavour of the wine (Tasting data appear to show tasters prefer wine made with ML01). • Generic GM-technology related questions: Consumer response, environmental risks

13. Comments: Health Canada Wines derived from the genetically modified wine yeast Saccharomyces cerevisiae ML01 Health Canada has notified Dr. Hennie van Vuuren of the University of British Columbia that it has no objection to the food use of a genetically modified wine yeast, Saccharomyces cerevisiae ML01, for use in winemaking in Canada, and of wines derived from the use of this yeast. The Department conducted a comprehensive assessment of wine yeast ML01 according to its Guidelines for the Safety Assessment of Novel Foods. These Guidelines are based upon internationally accepted principles for establishing the safety of foods with novel traits. See: http://www.hc-sc.gc.ca/fn-an/gmf-agm/appro/nf-an107decdoc-eng.php

14. The malolactic yeast ML01 Why rejected in SA? • Scientifically relevant questions were addressed in application • The GM yeast shows less molecular differences (transcriptome, proteome, metabolome) from its parental strain than the differences observed between this parent and other commercial wine yeast strains (health, ecology). • The two genes are naturally present in high numbers during wine fermentation (no significant increased risk of HGT) (ecology). • Socio-economic reasons: • Wine industry • Export market • Understandable in current situation, but will such decisions block all development in the field?

15. Other developments: Wine and Health • Increased levels of healthy substances • Phenolic compounds • Resveratrol (stilbenes) • Reduced levels of unwanted compounds • Carcinogens • Ethyl carbamate • Neurotoxins • Biogenic amines • Asthmatic chemical preservatives • Sulfites

16. Increased levels of resveratrol Phenylalanine Resveratrol  PAL C4H Cinnamic acid Coumaric acid 4CL VST 4CL p-Coumarolyl CoA Malonyl-CoA VST PAL = Phenylalanine ammonia-lyaseC4H = Cinnamate 4-hydroxylase4CL = CoA-ligaseVST = Resveratrol synthase Resveratrol Increasing levels of resveratrol • Resveratrol • 3,5,4'-trihydroxystilbene • cancer chemopreventive activity • Life prolonging in yeast and mice • prevention ofcoronary heart disease • French paradox

17. Bio-preservation • Winemaking heavily relies on the judicious use of SO2 to ensure high quality and microbial stability • Worldwide reduction in use of chemical preservatives • health risks • organoleptic changes • lower nutritional value • Consumer demand for products • less heavily preserved • less processed • higher quality • more natural • safer SHIFT IN RESEARCH TOWARDS BIOLOGICAL PRESERVATIVES

18. No growth Leucocin activity against Listeria Glucose oxidase activity yeast colonies YEp352 LCA1 Acetobacter aceti No growth Supernatant YEp352 LCA1 Gluconobacter oxydans

19. Conclusion • Would these yeast strains (ML01 and other GM yeast) be authorised for use if the same character traits had been obtained without the use of GM technology? • Is there any scientific evidence to support the fear that unpredicted and unwanted consequences may arise from the use of these strains (product quality / health / environment)? • Would these strains provide economic benefits to the wine industry? • Would these strains deliver benefits to the consumer?

20. Thank you …and can WE afford to ignore a technology with such innovation potential?