Rhodes>BM>Research

Research

Broad Research Interests of the Department

Biochemistry

Prof Adrienne L. Edkins -Cancer and Stem Cell Biology

Our group is studying the biochemistry and cell biology of the molecular chaperone, Hsp90, in cancer and stem cell biology. We use a range of biochemical (recombinant protein expression), molecular (quantitative RT-PCR, RNA interference) and cell biological (transfection, confocal microscopy and flow cytometry) techniques in order to elucidate the activity of Hsp90 and its co-chaperone, Hop, in specific cellular processes that underpin cancer and stem cell biology. In addition to our research on human chaperones, our research group is interested in comparative studies of Hsp90 complex from other organisms. These studies are interesting in that they may identify differences between the different systems that could be useful in understanding the species specific features of chaperones and may identify exploitable differences between the structure of the human and Hsp90 from other species to complement our studies to identify novel natural product inhibitors of Hsp90.

Prof Heinrich Hoppe - Malaria Parasite Cell Biology

Malaria parasites cause disease by cyclically invading and destroying human red blood cells. While inside the red blood cell, the parasite takes up and digests most of the surrounding red cell cytoplasm by a process known as haemoglobin endocytosis. Although this is a fundamental feature of malaria parasite biology, the molecular mechanisms by which it is mediated and regulated are not known. Prof. Hoppe’s group studies this process by characterizing transgenic parasites expressing GFP-tagged parasite homologs of proteins known to be involved in endocytosis in higher cells. An additional interest of the group is the development of cell-based protein-protein interactions assays that can be used for drug screening. A particular emphasis in this regard is setting up assays to measure the interactions of malaria parasite chaperones and co-chaperones. A third activity of the group is to establish and maintain malaria, cytotoxicity, microbial and HIV enzyme assays to support ongoing medicinal chemistry projects being conducted by the Rhodes Center for Chemico- and Biomedicinal Research.

Prof Brett Pletschke - Enzyme Biotechnology, Bioproducts

Our group’s research interest lies in the field of enzyme biotechnology, more specifically in the use of enzymes in bioconversion to generate bioproducts from renewable biological resources, e.g. lignocellulose and seaweeds (macroalgae) for the bioeconomy. Since 2006 we have established ourselves firmly in the area of carbohydrate active enzymes (CAZymes) and the synergisms between these enzymes (cellulases, xylanases and mannanases) - mainly for optimising biofuel production.  Currently (2019), we are looking at xylanases for improving digestibility of animal feeds, mannanases for the production of prebiotic manno-oligosaccharides (MOS), and the extraction of seaweed derived fucoidans and other enzyme inhibitors compounds from seaweeds for use as anti-diabetic/anti-obesity/anti-cancer agents.

Prof Ozlem Tastan Bishop - Bioinformatics

Prof Tastan Bishop's research interest combines structural bioinformatics and comparative genomics. Research projects in her group range from drug discovery to agricultural studies to databases. Various bioinformatics approaches are used to model protein structures, to analyse protein structure - function relationship, to do protein-ligand and protein-protein docking as well as molecular dynamics calculations. Further, tool development and database construction are important aspects of the group's work. For further information, visit RUBi webpage (click here).

Dr Brendan Wilhelmi

Dr Wilhelmi's research group investigates cytochrome P450 metabolism as well as target enzymes of neurodegenerative diseases. These enzymes are cloned and expressed, purified and their activity optimised and investigated against compounds of interest. The molecular bar-coding research aims to identify specific markers in different species, including single nucleotide polymorphisms in P450, cytochrome c oxidase and other hypervariable DNA regions for both diagnostic and identification purposes.

Dr Jo-Anne de la Mare - Novel inhibitors for triple negative breast cancer

Dr de la Mare is a member of the Biomedical Biotechnology Research Unit. Her research focuses on tripple-negative breast cancer (TNBC), a highly aggressive subtype of the disease that lacks the estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2/neu), making it very difficult to treat. Highly relevant to the African context is the fact that TNBC has been shown to be more prevalent in black women. This subtype has been linked to earlier age of onset, higher mortality and greater risk for metastasis. To date there remain limited treatment options available for TNBC patients. Dr de la Mare’s work focuses on the characterisation of TNBCs as well as the screening of novel small molecules of natural and synthetic origin against TNBC and other cancer cell lines. These novel compounds are sourced via an extensive network of local collaborators working in medicinal chemistry. An important part of the preclinical drug discovery process is the elucidation of the mechanism of action of a particular compound, the mode of cell death induced and signal transduction pathways perturbed. In particular, Dr de la Mare is interested in apoptosis and autophagy as cell death mechanisms and the role of DNA damage in mediating cytotoxicity. Dr de la Mare is currently engaged in a Sandisa Imbewu-funded collaboration with Prof Edkins, Prof Hoppe and Dr Abrahams that is focused on establishing a medium-high throughput mechanistic screening platform for both infectious and non-communicable diseases.

 

Microbiology

Prof Joanna Dames- Mycorrhizal Research Group

Mycorrhizal fungi are soil fungi which form a symbiotic relationship with the roots of the majority of plant species including many economically important crops. The Mycorrhizal Research Laboratory is dedicated to research in this field and research has focused on aspects of their biology, ecology, characterization, biodiversity, commercial application, their interaction with other soil microorganisms as well as benefits to both the soil environment and plant production.  Mycorrhizal types of interest are the ectomycorrhizal fungi, the arbuscular mycorrhizal fungi and the ericoid mycorrhizal fungi because of their importance in the Forestry, Agriculture, Horticulture and Rehabilitation industries.

Prof Rosemary Dorrington - Microbial Ecology and Marine Natural Products Research

This research forms part of a multidisciplinary programme (Chemistry, Marine Biology Geography and Microbiology) to study the role of the microbiota (focusing on bacteria and viruses) in marine ecosystems. Research projects include the role of the microbiota in determining ecosystem health in estuarine systems, the impact of global change on marine and terrestrial ecosystems in the Southern Ocean and studies on microbial symbionts associated with marine invertebrates and their  bioactive secondary metabolites.
Molecular Virology
This research aims to develop a fundamental understanding of the molecular biology of small insect RNA viruses as a model system for studying the biology of (+ve) ssRNA insect viruses.  Research projects include elucidating virus-host interactions during infection and virus replication; the molecular mechanisms of RNA packaging during virus particle assembly and the potential of modified virus particles for the development of drug and gene-delivery technologies.

Prof Caroline Knox - Molecular Virology

Research in Dr Knox’s laboratory is conducted in collaboration with Professor Martin Hill (Department of Zoology and Entomology, Rhodes University) and Dr Sean Moore (Citrus Research International) and focuses on the isolation and genetic characterisation of baculoviruses for the biocontrol of economically important insect pests. A second research interest, in collaboration with Professor Tom Wileman (University of East Anglia, UK) involves an investigation into the molecular mechanisms by which Picornaviruses interact with host cells during infection. Using biochemical assays and confocal microscopy, we are attempting to identify host components utilised by these viruses during the replication cycle.

Dr Garth Abrahams - Bacterial Pathogenesis

Many pathogenic bacteria have evolved mechanisms to facilitate their adherence and uptake into eukaryotic host cells. Within the intracellular environment, these pathogenic bacteria frequently modify or manipulate host cell functions and resources to promote their intracellular replication, survival and/or persistence. Several pathogenic bacterial species also capable of subverting host cell defences, thereby conferring these microbes with the ability to evade detection and elimination by host immune defence systems. The molecular mechanisms used by these bacteria to either adhere, enter, survive, replicate, and exit host cells is, however, only partially understood. The research in our laboratory is directed at studying the pathogenic interactions that occur between bacteria such as S. enterica and M. tuberculosis and their respective host cells.

Last Modified: Wed, 11 Dec 2019 11:39:22 SAST

Rhodes>BM>Research

Research

Cancer and Stem Cell Biology

Prof Adrienne L. Edkins

Our group is studying the biochemistry and cell biology of the molecular chaperone, Hsp90, in cancer and stem cell biology. We use a range of biochemical (recombinant protein expression), molecular (quantitative RT-PCR, RNA interference) and cell biological (transfection, confocal microscopy and flow cytometry) techniques in order to elucidate the activity of Hsp90 and its co-chaperone, Hop, in specific cellular processes that underpin cancer and stem cell biology. In addition to our research on human chaperones, our research group is interested in comparative studies of Hsp90 complex from other organisms. These studies are interesting in that they may identify differences between the different systems that could be useful in understanding the species specific features of chaperones and may identify exploitable differences between the structure of the human and Hsp90 from other species to complement our studies to identify novel natural product inhibitors of Hsp90.

Malaria Parasite Cell Biology

Prof Heinrich Hoppe

Malaria parasites cause disease by cyclically invading and destroying human red blood cells. While inside the red blood cell, the parasite takes up and digests most of the surrounding red cell cytoplasm by a process known as haemoglobin endocytosis. Although this is a fundamental feature of malaria parasite biology, the molecular mechanisms by which it is mediated and regulated are not known. Prof. Hoppe’s group studies this process by characterizing transgenic parasites expressing GFP-tagged parasite homologs of proteins known to be involved in endocytosis in higher cells. An additional interest of the group is the development of cell-based protein-protein interactions assays that can be used for drug screening. A particular emphasis in this regard is setting up assays to measure the interactions of malaria parasite chaperones and co-chaperones. A third activity of the group is to establish and maintain malaria, cytotoxicity, microbial and HIV enzyme assays to support ongoing medicinal chemistry projects being conducted by the Rhodes Center for Chemico- and Biomedicinal Research.

Enzyme Biotechnology, Bioproducts

Prof Brett Pletschke

Our group’s research interest lies in the field of enzyme biotechnology, more specifically in the use of enzymes in bioconversion to generate bioproducts from renewable biological resources, e.g. lignocellulose and seaweeds (macroalgae) for the bioeconomy. Since 2006 we have established ourselves firmly in the area of carbohydrate active enzymes (CAZymes) and the synergisms between these enzymes (cellulases, xylanases and mannanases) - mainly for optimising biofuel production.  Currently (2019), we are looking at xylanases for improving digestibility of animal feeds, mannanases for the production of prebiotic manno-oligosaccharides (MOS), and the extraction of seaweed derived fucoidans and other enzyme inhibitors compounds from seaweeds for use as anti-diabetic/anti-obesity/anti-cancer agents.

Bioinformatics

Prof Ozlem Tastan Bishop

Prof Tastan Bishop's research interest combines structural bioinformatics and comparative genomics. Research projects in her group range from drug discovery to agricultural studies to databases. Various bioinformatics approaches are used to model protein structures, to analyse protein structure - function relationship, to do protein-ligand and protein-protein docking as well as molecular dynamics calculations. Further, tool development and database construction are important aspects of the group's work. For further information, visit RUBi webpage (click here).

Dr Brendan Wilhelmi

Dr Brendan Wilhelmi

Dr Wilhelmi's research group investigates cytochrome P450 metabolism as well as target enzymes of neurodegenerative diseases. These enzymes are cloned and expressed, purified and their activity optimised and investigated against compounds of interest. The molecular bar-coding research aims to identify specific markers in different species, including single nucleotide polymorphisms in P450, cytochrome c oxidase and other hypervariable DNA regions for both diagnostic and identification purposes.

Novel inhibitors for triple negative breast cancer

Dr Jo-Anne de la Mare

Dr de la Mare is a member of the Biomedical Biotechnology Research Unit. Her research focuses on triple-negative breast cancer (TNBC), a highly aggressive subtype of the disease that lacks the estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2/neu), making it very difficult to treat. Highly relevant to the African context is the fact that TNBC has been shown to be more prevalent in black women. This subtype has been linked to earlier age of onset, higher mortality and greater risk for metastasis. To date there remain limited treatment options available for TNBC patients.

Mycorrhizal Research Group

Prof Joanna Dames

Mycorrhizal fungi are soil fungi which form a symbiotic relationship with the roots of the majority of plant species including many economically important crops. The Mycorrhizal Research Laboratory is dedicated to research in this field and research has focused on aspects of their biology, ecology, characterization, biodiversity, commercial application, their interaction with other soil microorganisms as well as benefits to both the soil environment and plant production.  Mycorrhizal types of interest are the ectomycorrhizal fungi, the arbuscular mycorrhizal fungi and the ericoid mycorrhizal fungi because of their importance in the Forestry, Agriculture, Horticulture and Rehabilitation industries.

Microbial Ecology and Marine Natural Products Research

Prof Rosemary Dorrington

More than half of new pharmaceutical drugs on the market or in clinical trials are natural products (NPs) and their derivatives, the majority of which come from marine sources. Prof Dorrington’s research is focused on harnessing the pharmaceutical potential of bioactive marine NPs produced by marine sponges, ascidians and their associated microbiota. The biodiscovery pipeline includes searching for new invertebrate species producing novel bioactive NPs, using metabolomics and microbial genomics approaches to investigate environmental factors that influence secondary metabolite production and to elucidate putative biosynthetic pathways

Molecular Virology

Prof Caroline Knox

Research in Prof Knox’s laboratory focuses on the molecular biology of two economically important families of viruses: the Baculoviridae and the Picornaviridae. Baculoviruses are double-stranded DNA viruses that infect insects and can therefore be exploited for the control of phytosanitory crop pests such as the false codling moth. This research, conducted in collaboration with the Centre for Biological Control (Rhodes University) and Citrus Research International (Port Elizabeth) involves the genetic and biological characterisation of viruses infecting a range of crop pests. Picornaviruses are single-stranded RNA viruses that cause a range of serious human and animal diseases. This research involves an investigation into the molecular mechanisms by which Picornaviruses interact with host cells during replication and assembly, with a view to uncovering novel antiviral strategies for disease control.

Bacterial Pathogenesis

Dr Garth Abrahams

Many pathogenic bacteria have evolved mechanisms to facilitate their adherence and uptake into eukaryotic host cells. Within the intracellular environment, these pathogenic bacteria frequently modify or manipulate host cell functions and resources to promote their intracellular replication, survival and/or persistence. Several pathogenic bacterial species also capable of subverting host cell defences, thereby conferring these microbes with the ability to evade detection and elimination by host immune defence systems. The molecular mechanisms used by these bacteria to either adhere, enter, survive, replicate, and exit host cells is, however, only partially understood. The research in our laboratory is directed at studying the pathogenic interactions that occur between bacteria such as S. enterica and M. tuberculosis and their respective host cells.