- Paramecium bursaria Chlorella virus 1 encodes two enzymes involved in the biosynthesis of GDP-L-fucose and GDP-D-rhamnose. Tonetti, M., Zanardi, D., Gurnon, J.R., Fruscione, F., Armirotti, A., Damonte, G., Sturla, L., De Flora, A., Van Etten, J.L. J. Biol. Chem. (2003)