The Molecular Plant Physiology group was established in 1998 when Professor Karl Kunert joined FABI. Since then the group has grown and is currently headed by Dr Juan Vorster. We collaborate with various groups from around the world, each brining unique specialities, to understand plant development and the response of plant towards stress. Using a multi-disciplinary approach we hope to obtain a holistic view of the changes in the plant under stress. On a genomic level we have studies stress induced mutations and rearrangements of the genome, we are also using transcriptomics to study and identify genes and pathways that are important during the stress response. On a protein level we are especially interested in the role cysteine proteases as well as cysteine protease inhibitors play during development and senescence. Here we make use of in silico protein modelling to study protein-protein interactions as well as to predict the effect of mutations on inhibitor binding. Through protein engineering and enzyme kinetics we then evaluate the effect of these changes on inhibitor strength and specificity. We also measure protease activity and changes in the REDOX state in different tissues and under different stress conditions. To complement the molecular data we also follow and characterize various physiological and phenotypic changes in the plants we study. The ultimate aim is to identify usable molecular, biochemical or phenotypic markers that can be used to develop plants better adapted to stress in a changing environment.

New Publications

Mbedzi PP, Van den Hooven L, Vorster BJ , Van der Waals J. (2019) Screening for Sclerotinia sclerotiorum resistance using detached leaf assays and simple sequence repeat markers in soybean cultivars. Crop Protection 215:104909. 10.1016/j.cropro.2019.104909 PDF
Kibido T, Kunert K, Makgopa M, Greve M, Vorster BJ . (2019) Improvement of rhizobium‐soybean symbiosis and nitrogen fixation under drought. Food and Energy Security :e117. 10.1002/fes3.177 PDF
Juan Vorster, Chris Cullis, Karl Kunert. (2019) Plant Vacuolar Processing Enzymes. Frontiers in Plant Science :00497. 10.3389/fpls.2019.00479 PDF
Cullis C, Lawler DW, Chimwamurombe P, Kunert K, Bbebe N, Vorster J. (2019) Development of marama bean, an orphan legume, as a crop. Food and Energy Security e00164:1-12. 10.1002/fes3.164 PDF
NM Okumu, BJ Vorster, CF Reinhardt. (2019) Growth-stage and temperature influence glyphosate resistance in Conyza bonariensis (L.) Cronquist.. South African Journal of Botany 121:248-256. 10.1016/j.sajb.2018.10.034 PDF
Cristopher Cullis, Percy Chimwamurombe, Nigel Barker, Karl Kunert, Juan Vorster. (2018) Orphan Legumes Growing in Dry Environments: Marama Bean as a Case Study. Frontiers in Plant Science 9:11999. 10.3389/fpls.2018.01199 PDF
Magdeleen Cilliers, Stefan van Wyk, Phillipus van Heerden, Karl Kunert, Juan Vorster. (2018) Identification and changes of the drought-induced cysteine protease transcriptome in soybean (Glycine max) root nodules. Journal of Experimental and Environmental Botany 148:59-69. 10.1016/j.envexpbot.2017.12.005
Priyen Pillay, Karl Kunert, Eugene Makgopa, Chris Cullis, Juan Vorste. (2016) Agroinfiltration contributes to VP1 recombinant protein degradation. Bioengineered 7(6):459-477. 10.1080/21655979.2016.1208868 PDF
Foyer CH, Lam H-M, Nguyen HT, Siddique KHM, Varshney RK, Colmer TD, Cowling W, Bramley H, Mori TA, Hodgson JM, Cooper JW, Miller AJ, Kunert K, Vorster J, Cullis C, Ozga JA, Wahlqvist ML, Liang Y, Shou H, Shi K, Yu J, Fodor N, Kaiser BN, Wong F-L, Valliyodan B, Considine MJ. (2016) Neglecting legumes has compromised human health and sustainable food production. Nature Plants 2:16112. 10.1038/nplants.2016.112
Pillay P, Kunert KJ, van Wyk S, Makgopa ME, Cullis CA, Vorster BJ. (2016) Agroinfiltration contributes to VP1 recombinant protein degradation. Bioengineered 7(6):459-477. 10.1080/21655979.2016.1208868
Kunert K, Vorster BJ, Fenta BA, Kibido T, Dionisio G, Foyer CH. (2016) Drought stress responses in soybean roots and nodules. Frontiers in Plant Science 7(1015) 10.3389/fpls.2016.01015 PDF
Sapountzis P, de Verges J, Rousk K, Cilliers M, Vorster BJ, Poulsen M. (2016) Potential for Nitrogen Fixation in the Fungus-Growing Termite Symbiosis. Frontiers in Microbiology 7:1993. 10.3389/fmicb.2016.01993 PDF
Naidoo SIM, Laurie SM, Odeny DA, Vorster BJ, Mphela WM, Greyling MM, Crampton BG. (2016) Genetic analysis of yield and flesh colour in sweetpotato. African Crop Science Journal 24(1):61-73. 10.4314/acsj.v24i1.5 PDF
Sainsbury F, Jutras PV, Vorster J, Goulet MC , Michaud D. (2016) A Chimeric Affinity Tag for Efficient Expression and Chromatographic Purification of Heterologous Proteins from Plants. Frontiers in Plant Science 7:141. 10.3389/fpls.2016.00141
Van Wyk SG, Kunert KJ, Cullis CA, Pillay P, Makgopa ME, Schluter U , Vorster BJ. (2016) The future of cystatin engineering. Plant Science 246:119-127. 10.1016/j.plantsci.2016.02.016 PDF
van Wyk SG, Du Plessis M, Cullis CA, Kunert KJ, Vorster BJ. (2014) Cysteine protease and cystatin expression and activity during soybean nodule development and senescence. BMC Plant Biology 14(294) 10.1186/s12870-014-0294-3
Pillay P, Schlüter U, van Wyk S, Kunert KJ, Vorster BJ. (2014) Proteolysis of recombinant proteins in bioengineered plant cells. Bioengineered 5(1):15-20. 10.4161/bioe.25158
Vorster BJ, Schlüter U, du Plessis M, van Wyk S, Makgopa ME, Ncube I, Quain MD, Kunert K, Foyer CH. (2013) The Cysteine Protease – Cysteine Protease Inhibitor System Explored in Soybean Nodule Development. Agronomy 3(3):550-570. 10.3390/agronomy3030550
Vorster B, Schlüter U, du Plessis M, van Wyk S, Makgopa M, Ncube I, Quain M, Kunert K, Foyer C. (2013) The cysteine protease–cysteine protease inhibitor system explored in soybean nodule development. Agronomy 3(3):550-570. 10.3390/agronomy3030550
Mphangwe NIK, Vorster J, Steyn JM, Nyirenda HE, Taylor NJ, Apostolides Z. (2013) Screening of Tea (Camellia sinensis) for Trait-Associated Molecular Markers. Applied Biochemistry and Biotechnology 171:437-449. 10.1007/s12010-013-0370-4