1. Catalysis and Peptide Research Unit, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
2. School of Chemistry and Physics, University of KwaZulu-Natal, Durban, South Africa
3. Faculty of Science and Agriculture, Department of Chemistry, University of Zululand, Richards Bay, South Africa
4. Center for Tuberculosis Research, Division of Infectious Diseases, School of Medicine, Johns Hopkins University, Baltimore, MD, USA