The algae are a group of organisms that are spread across the broad expanse of eukaryotic diversity and even include the cyanobacteria.
Phycology is the study of algae - a group of organisms that are spread across the broad expanse of eukaryotic diversity and even include the cyanobacteria. Not only are their origins diverse, but so too are their habitats; from marine to freshwater, thermal springs to snow, aquatic to terrestrial or even aerial habitats. In body form they are also surprisingly diverse, from microscopic unicells, some smaller than many bacteria, to large kelps of greater than 30 metres. While their unifying (but not exclusive) character is that they are photosynthetic, some are voracious mixotrophs hunting other life forms while others have become parasitic, such as malaria. They, or their products, have considerable impact in medicinal use and in our everyday lives. Primary production by algae is gaining increasing support as a means to feed livestock or our energy needs without compromising precious land required for normal agricultural purposes and is an important source of human food or vitamins, particularly in the orient. This incredible scope provides a platform for an even greater scope for research using such organisms as subject material. In spite of our distance from the sea, much of the research efforts in this School are concentrated on marine microalgae.
Surveys of estuarine and inshore microscopic plankton and benthos form a continuous basis for much research in our laboratories. We have been responsible for discovering and describing many new species, some with significant systematic impact and often involving international collaboration. Much of our current systematic research is done in collaboration with researchers in Japan, Germany and Norway and this provides important baseline data for future reference. It requires exacting behavioural or live observations using light microscopy and ultrastructural characterization using transmission electron microscopy, supplemented with DNA sequencing and phylogenetic analysis .As a direct result of this work, we have established a strong culture collection in the School which also feeds into the South African National Phycology Culture Collection (sanpcc.org.za), established in 2016 by Dr P Durand. Developmental and cell biological studies have also been undertaken using selected microalgal groups. Toxic marine algae and their economic importance are being investigated in collaboration with the Department of Forestry and Fisheries (DAFF). Additional foci have been the determination of optimal biofeed production in selected marine haptophytes for downstream purposes and looking for evidence of programmed cell death in bloom producing algae.
Staff involved in this area of research:
- Professor Richard Pienaar
- Associate Professor Stuart Sym
- Dr Pierre Durand (Evolutionary Studies Institute, Wits University) – programmed cell death
- Dr Grant Pitcher (DAFF, Cape Town) – programmed cell death and harmful algal blooms
- Professor Vincent Gray (School of MCB, Wits Univeristy) – algae for biofeed
- Professor Takeo Horiguchi (Hokkaido University, Sapporo, Japan) – algal systematics
- Professor Shoichiro Suda (University of the Ryukyus, Okinawa, Japan) – algal systematics
- Professor Masanobu Kawachi (National Institute for Environmental Studies, Tsukuba , Japan) – algal systematics
- Professor Bente Edvardsen and Dr Elianne Egge (University of Oslo, Norway) – algal systematics
- Professor Michael Melkonian and Dr Birger Marin(University of Cologne, Germany) – algal systematics
Tutuzwa Xuma (PhD) Supervisors: Professor S Sym and Dr P Durand
The detailed ultramicroscopy of programmed cell death in Prorocentrum triestinum Schiller, a bloom-forming dinoflagellate responsible for an anoxic bloom event in Elands Bay 2015
An anoxic bloom in 2015, responsible for the mass mortality of rock lobster in Elands Bay, was dominated by Prororcentrum triestinum. The collapse of the bloom was always considered to be caused by lack of nutrition, but this has never been tested. The ultrastructure of a healthy culture of this organism, isolated from the bloom, will be compared with that at the collapse of the bloom and with that of cultures subjected to signals known to initiate programmed cell death in other algae. Should evidence of programmed cell death in this collapse be demonstrated, the potential exists to exact more control on the termination of a harmful or potentially harmful event in future.
Natalie Sloane(MSc, Faculty of Health Sciences) Supervisors: Dr G Gordon (Forensic Science), Professor S Sym and Mr L Hill (Forensic Science)
Pig decomposition in a pond: the potential use of epiphytic algae to establish the post-mortem submersion interval.
The post mortem interval (PMI) is used to determine the time since death after a corpse is discovered. The earlier stages may be determined by enumerating or observing the stages of insect (usually fly maggots or carrion beetle larvae) development in the corpse. Submersed corpses offer a challenge to this approach because they are inaccessible to these terrestrial organisms. This project sets out to determine the usefulness of algal epiphytes (number and characterisation) on the decomposing body to determine its post mortem submersed interval (PMSI) in a standing body of water and using a stillborn piglet as a proxy for a human corpse.