Prof. W.H. van Zyl

The focus of Prof Willem Heber van Zyl’s research programme is: "Expression of commercial important genes in yeast and filamentous fungi for (a) the production of enzymes, (b) the improvement of yeasts for bioethanol production and (c) the production of pharmaceutically important proteins".

Part of Prof. Van Zyl’s research focuses on the genetic manipulation of S. cerevisiae to utilize cellulose and hemicellulose. The yeast S. cerevisiae cannot utilize cellulose or xylan, but the monosaccharides glucose and xylulose. At large, the research involves the isolation and expression of genes encoding cellulases and hemicellulases, as well as enzymes for xylose utilization in S. cerevisiae, to allow the yeast to utilize these abundant polysaccharides for the production of bioethanol. For this research follows the utilization of cellulases and hemicellulases in other applications, for example enzyme additions for ruminant feed formulations (in collaboration with Prof. Chrisjan Cruywagen of the Department of Animal Sciences), as well as the food industries, for e.g. coffee and tea (in collaboration with Dr. M. Bloom).

Furthermore, his research group is also exploring the expression of the HBsAg protein of Hepatitis B-virus (HBV) in the filamentous fungus, Aspergillus niger, for the possible development of subunit vaccines against HBV. This project is done together with Dr. Johann Görgens of Process engineering, as well as in collaboration with TNO ( Netherlands). New projects that have started focus on the production of vaccines against two other prominent virus diseases, Rotavirus that causes diarrhoea and human Papilloma virus (HPV) that are responsible for most cases of female cervical cancer. The expression systems of choice for Rotavirus and HPV subunit vaccine production are Pichia pastoris and Hansenula polymorpha.

1. Biofuels