Project Description


Grape Biology/Biotechnology/Improvement
Grapevine x Environment x Management Interactions
Wine Production and Analytics
Chemistry and Spectroscopy


I completed my studies at the University of Cape Town where I obtained undergraduate degrees in Biochemistry and a doctorate in Molecular and Cell Biology. My PhD thesis entitled The role of polyphenols and the cell wall in relation to the desiccation tolerance of the resurrection plant Myrothamnus flabellifolia (Welw.) was performed under the principal supervision of the late Associate Professor Wolf Brandt. Through this research work, while under the co-supervision of Professor Jill Farrant, I developed a keen interest in the desiccation and drought tolerance mechanisms of plants. In addition, I became very interested in the chemistry of plant polyphenols and the biochemistry of plant cell walls. During my PhD I spent research periods at the University of Rouen in France where I developed expertise in the biochemistry and microscopy of plant cell walls under the supervision of Professor Azeddine Driouich. After obtaining my doctorate I worked as a post-doctoral fellow at the University of Edinburgh in Scotland. My research focused on the mechanisms of phenolic coupling, using isotope-based metabolic methods, within the walls of suspension cultured maize (Zea mays) cells in the laboratory of Professor Stephen Fry. Towards the end of 2007 I joined the academic staff of the former Institute for Wine Biotechnology (IWBT) now the South African Grape and Wine Research Institute (SAGWRI) at Stellenbosch University where I was appointed as an academic researcher and subsequently promoted to senior researcher.

My research area forms part of the grapevine molecular physiology programme aimed at improving the scientific understanding around the areas of disease resistance, fruit quality and abiotic stress (i.e. drought) tolerance of Vitis vinifera (grapevine) cultivars. Current research includes unravelling the in vitro, in vivo and in planta interactions between endopolygalacturonases, polygalacturonase inhibitory proteins (PGIPs) and the cell wall of Vitis vinifera in response to fungal pathogen infection. Pathogens studied include Botrytis cinerea, a fungus responsible for both grey and noble rot in grapevine. Areas of interest include grape berry ripening and water deficit from the perspective of the plant cell wall. I also conduct research in wine chemistry concerning the role of carbohydrate active enzymes in grape berry deconstruction and polyphenol-polysaccharide release during winemaking. A further strand of research undertaken involves investigating the role of mannoproteins in relation to growth and fermentation phenotypes of wine yeast (Saccharomyces cerevisiae). I continue to maintain an interest in plant desiccation tolerance. The approach taken is multi-disciplinary in nature involving techniques from a range of fields (i.e. molecular biology, chemistry, biochemistry (enzymology), microscopy, immunocytochemistry and spectroscopy). Research funders include the National Research Foundation (South Africa), Stellenbosch University, Winetech (Wine Industry Network of Expertise and Technology), SATI (South African Table Grape Industry), contract research (e.g. BIO-Laffort, Bordeaux, France) and South African Government THRIP (Technology and Human Resources in Industry Programme).


  • +27 21 808 2733

Room 2005, JH Neethling Building, Victoria Street
7600 Stellenbosch, South Africa


Selected relevant publications

Florent Weiller, Lorenz Gerber, Johan Trygg, Jonatan U. Fangel, William G.T. Willats, Azeddine Driouich, Melané A Vivier and John P. Moore. 2020. Overexpression of VviPGIP1 and NtCAD14 in tobacco screened using glycan microarrays reveals cell wall reorganisation in the absence of fungal infection. Vaccines. 8, 388

Yu Gao, Anscha J. J. Zietsman, Melané A Vivier and John P. Moore. 2019. Deconstructing wine grape cell walls with enzymes during winemaking: new insights from glycan microarray technology. Molecules 24 (1), 165.

Anscha J. J. Zietsman, John P. Moore, Jonatan U. Fangel, William G.T. Willats, Melané A. Vivier. 2017. Combining hydrothermal pretreatment with enzymes de-pectinates and exposes the inner most xyloglucan-rich hemicellulose layers of wine grape pomace. Food Chemistry 232, 340-350.

Yu Gao, Jonatan U. Fangel, William G.T. Willats, Melané A Vivier and John P. Moore. 2016. Effect of intra-vineyard ripeness variation on the efficiency of commercial enzymes on berry cell wall deconstruction under winemaking conditions Journal of Agricultural and Food Chemistry 64, 3862-3872.

Yu Gao, Jonatan U. Fangel, William G.T. Willats, Melané A Vivier and John P. Moore. 2015. Dissecting the polysaccharide-rich grape cell wall matrix during the winemaking process using high-throughput and fractionation methods. Carbohydrate Polymers 133, 567-577