1. Faculty of Health Sciences, University of Johannesburg, PO Box 17011, Doornfontein 2028, South Africa
2. BioPep Peptide Group, Department of Biochemistry, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa
3. Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa