Maize as production and delivery vehicle of edible vaccines against the enterotoxigenic Escherichia coli and the swine transmissible gastroenteritis (TGE)

Plants are becoming increasingly important as a production system for biopharmaceuticals and industrially important proteins. The work presented in this dissertation showed that maize can be used as a source and delivery vehicle for oral vaccines. Antigenic proteins from two economically important pathogens, enterotoxigenic Escherichia coli (E. coli ) and the swine transmissible gastroenteritis virus (TGEV) were expressed in transgenic maize.;This study showed that subunits of the E. coli heat labile enterotoxin (LT) can be synthesized in transgenic maize tissues, correctly processed and assembled in maize tissue. The role of regulatory sequences such as promoters, targeting and retention signals in accumulation of LT-B in transgenic maize kernels was studied. The seed specific 27 kDa gamma zein promoter achieved a significantly higher level of LT-B expression in kernels compared to the constitutive CaMV 35S promoter. The use of the endoplasmic reticulum retention motif SEKDEL significantly enhanced kernel accumulation of LT-B. The LT-13 gene was normally transmitted over three generations.;Maize generated LT-B had biochemical, biophysical, and immunogenic properties of the bacterial protein. Oral administration of transgenic maize expressing LT-B in BALB/c mice induced elevated titers of serum and mucosal antibodies, which protected the immunized animals from subsequent challenge with LT and Cholera toxin (CT).;Using two synthetic genes for the LT toxin subunits, LT-A and LT-B, a non-toxic derivative of the heat labile toxin, LTK63, was expressed in transgenic maize callus. This mutant toxin assembled in maize callus tissue, showing that complex folding of foreign antigens could be achieved in transgenic maize tissues. This mutant derivative was shown to be more immunogenic than the bacteria derived LT-B.;We fused an N-terminal domain of the spike (S) protein of the swine transmissible gastroenteritis virus to the A subunit of LT, and coexpressed this fusion with LT-B in transgenic maize callus. Expression of the fusion proteins and LT-B was observed in callus.;This work demonstrates that maize, a key ingredient in food and feed industry, can be used as a source and delivery vehicle of functional antigens for use as oral vaccines. Maize holds great potential for the generation of human and livestock vaccines, and this work lays the foundation for the development of vaccines against other pathogens in transgenic maize

The role of the discretionary grant in the dynamics of capability creation and exploitation in a public research organization : a case study of the CSIR

Public research institutions (PRIs) are tasked with generating new knowledge, as well as adding value to existing knowledge in order to come up with innovations that can contribute to national competitiveness. To this end, government provides discretionary or parliamentary grants to allow the public research institutions to execute their mandates by carrying out exploratory activities and exploitative activities in research and development.The study aimed to establish the role of the parliamentary grant in supporting the research and development endeavours of a public research institute, with a particular focus on the management of exploration and exploitation tensions in investing the parliamentary grant. The sustainability of the PRI was sus assessed using operating profits as a proxy. The relationships between levels of investment in exploratory and exploitative actives were assessed, as was the role of the innovation system in influencing the sustainability of the PRI. We use the Council for Scientific and Industrial Research (CSIR) the largest scientific research entity in South Africa, and its operational units as a case study.Consistent with information that is available in the literature, the data from this study shows that the discretionary grant plays a critical role as a funding stream for public research institutes, contributing to the effective execution of research and development activities of the entity. The discretionary grant is key in seeding new national competencies, and is a key initial investment in enabling the PRI to establish itself, generate outputs and outcomes that herald its competencies and thus position itself to earn other forms of income.The discretionary grant is invested for exploratory and exploitive activities. Exploratory activities generate new knowledge, which is necessary for competitiveness. Exploitative activities utilise existing knowledge to provide innovations that find utility in industries and the public sector. The manner in which the investment is split between exploration and exploitation was shown to be critical to the long term sustainability of the enterprise. Skewing investment in either exploration or exploitation alone is detrimental to sustainability.The optimal split of the discretionary grant between exploration and exploitation was found to be dependent on several factors, to include, the technology bases of the industries in which the entity operates and the connectivity and paths of knowledge flow in the innovation systems nationally and globally.Inability to earn other forms of income is in itself a threat to the long term sustainability, particularly in fiscally constrained environments that are typical of emerging economies. The ability to earn external income provides options for investment of the PG in building its capability base. Notable here is the fact that the absorptive capacity of the industry sector in the first place, the innovation system in which the entity operates and the connectedness of the entity within the system appear to have important influences on ability to earn other forms of income. In such cases, strategic decisions have to be made on whether the sector remains strategic enough for the country in deciding on continued investment.While the information derived from this study is very specific to the CSIR, a combination of the data and information in the literature provides insights that are applicable to other public research institutes, particularly in developing economies.Dissertation (MBA)--University of Pretoria, 2012.Gordon Institute of Business Science (GIBS)unrestricte

Two different banana NPR1-like coding sequences confer similar protection against pathogens in Arabidopsis

Differences between the coding sequences of two banana homologues of the Non-expressor of Pathogenesis-Related 1 (NPR1) genes (MNPR1A and MNPR1B) were investigated as a possible cause for the differential activity of the two genes. Each of the MNPR1 coding sequences were expressed under the control of the cauliflower mosaic virus 35S promoter/terminator sequences in the transgenic Arabidopsis npr1-2 mutant. These MNPR1-expressing plants were then exposed to either the biotrophic oomycete Hyaloperonospora arabidopsidis, the necrotrophic fungus Botrytis cinerea, or the hemi-biotrophic bacterial pathogen Pseudomonas syringae. Expression of either MNPR1A or MNPR1B increased Pathogenesis-related 1 (PR-1) transcription in a similar manner in mutant plants and reduced pathogen growth, restoring resistance of the Arabidopsis npr1-2 mutant plants to pathogens. Sequence differences between MNPR1A and MNPR1B coding sequences did not affect MNPR1activity, suggesting a possible role for the involvement of other regulatory sequences in differential MNPR1 gene expression.Rockefeller Foundation and the University of Pretoria.http://link.springer.com/journal/12042hb2016Forestry and Agricultural Biotechnology Institute (FABI)Plant Scienc

Physiological responses of selected African sorghum landraces to progressive water stress and re-watering

Sorghumis particularly drought tolerant compared with other cereal crops and is favoured for subsistence farming in water scarce regions of the world. This study was conducted to identify South African sorghum landraces with superior drought tolerance compared with a drought-tolerant breeding line (P898012). Seedlings of 14 South African sorghumlandrace accessions were initially screened for drought tolerance by assessing percentage leaf water content (LWC) during progressive water deficit. Four landraces (designated LR5, LR6, LR35, and LR36) recorded higher LWC than P898012. These were subsequently evaluated with P898012 during the reproductive growth stage, for their physiological responses to mild (4 days) and severe (6 days)water stress treatments and a moderate re-watered treatment on day 7. Plant height, soil moisture, and LWC were measured during harvests. Chlorophyll, carotenoid, and proline contents were quantified. All five genotypes maintained LWC above 80% during mild and severe stress treatments. For LR35 and LR36, LWC were recorded within 8% less in comparison to their well-watered controls following the moderate re-watered treatment. Significantly higher chlorophyll and carotenoid contents were recorded for both LR6 and LR35 in comparison to P898012 during severe stress. When LWC was reduced in LR36 (to 73.68%) and LR35 (to 73.51%), their proline content significantly increased by 14- and 16-fold, respectively. In this study,we have identified four previously uncharacterised sorghum genotypes exhibiting drought tolerance and described their physiological responses during water deficit and moderate re-watering. Aside from their application to breeding, these landraces are valuable resources to elucidate genetic mechanisms that enable drought tolerance in South African sorghum.Council for Scientific and Industrial Research (CSIR) - Biosciences, Pretoria and the Gauteng Department of Agriculture and Rural Development (GDARD), South Africa. Ms Natrisha Devnarain was awarded a Professional Development Programme (PDP) PhD Scholarship from DST-NRF to work on this project.http://www.elsevier.com/locate/sajb2017-03-31hb201

Biolistic mediated sorghum (sorghum bicolor L. Moench) transformation via mannose and bialaphos based selection systems

The efficiency of the bialophos (bar) and phosphomannose isomerase (pmi) selectable markers in microprojectile mediated transformation of P898012, a sorghum inbred line generally considered amenable to in vitro manipulation was investigated. Two plasmids containing bar gene, encoding bialaphos resistance and manA gene, for phosphomannose isomerase, both under the control maize ubiquitin promoter and nopaline synthase terminator were used to transform Immature Zygotic Embroys (IZE) of sorghum via particle bombardment using a particle infolw gun. Transgene integration in putatively trangenic plants was confirmed by PCR and Southern blot analysis. The expression of the bar gene in transgenic plants was demonstrated by the BASTA laef painting assay. Present results indicated a transformation efficiency of 0.11% and 75% escapes in the apparent bialaphos resistant plants. A transformation efficiency of 0.77% was observed on manA selection and all plants recovered contained the manA gene. Besides an improved transformation efficiency, mannose selection offers a more environmentally sound system as sugar metabolism is considered ecologically neutral should it inadvertently be transformed to wil sorghum species.We wish to thank the European Commission for the finacial support. Thanks to Moses Mokoena, Rufus Khonoti, Gugulethu Ngwenya and Jeffrey Mathabe for their technical Support

FABI, Biennial Report 2007/2008

Biennial report for the Forestry and Agricultural Biotechnology Institute (FABI) for the years 2007/2008.ACIAR (Australia), Agropolis Advanced Research Platform (France), Amathole Forestry, Banana Growers Association of South Africa, Belgium Embassy, BIOPAD, Central Timber Co-operative (CTC), China/South African Governments Agreement, Chinese Academy of Forestry, CIRAD, Citrus Growers Association, CGIAR Generation Challenge Programme, CNRS/South African Government Agreement, CSIR, DFG (Deutche Forshungs-Gemeinschaft: German Research Foundation), Department of Water Affairs and Forestry (DWAF), Department of Trade and Industry through THRIP initiative, Department of Science and Technology through the Innovation Fund and CTHB, Department of Science and Technology through the NRF, Department of Science and Technology, Du Roi QMS, EARO Ethiopia, ESKOM, European Union 6th Framework, Flemish/South African Governments Agreement, Forestry South Africa, Global Forestry Products, Hans Merensky Holdings, Hans Merensky Foundation, Innovation Fund, International Institute of Tropical Agriculture (IITA), Italian/South African Governments Agreement, Komatiland Forest Research (KLF), Loskop Irrigation Board, Mellon Foundation, Ministry of Education - China, Ministry of Science and Technology - China, Mondi, Mondi Shanduka, Mountain to Ocean (MTO) Forestry, National Bioinformatics Network, National Natural Science Foundation - China, National Research Foundation (NRF), NCT, Norway/South African Governments Agreement, PlantBio – National Innovation Centre in Plant Biotechnology, Protein Research Foundation, Rockefeller Foundation, SAFCOL/Komatiland Forestry, Sappi, SIDA/South African Government Agreement, South African Wattle Growers Union (SAWGU), Syngenta South Africa, Tanzanian Government, Technology and Human Resources and Industry Programme (THRIP), Thuthuka, Tuscan Namibia/DAAD (Germany), TWK, UP Research Development Fund, Water Research Commission, Winter Cereal Trus

FABI, Biennial Report 2005/2006

Biennial report for the Forestry and Agricultural Biotechnology Institute (FABI) for the years 2005/2006.ACIAR (Australia), Agropolis Advanced Research Platform (France), Amathole Forestry Banana Growers Association of South Africa, Belgium Embassy, BIOPAD, Central Timber Co-operative (CTC), China/South African Governments Agreement, CIRAD, Citrus Growers Association, CGIAR Generation Challenge Programme, CNRS/South African Government Agreement, CSIR, DFG (Deutche Forshungs- Gemeinschaft: German Research Foundation), Department of Water Affairs and Forestry (DWAF), Department of Trade and Industry through THRIP initiative, Department of Science and Technology through the Innovation Fund and CTHB, Department of Science and Technology through the NRF, Du Roi QMS, EARO Ethiopia, ESKOM, European Union, Flemish/South African Governments Agreement, Forestry South Africa, Global Forestry Products, Hans Merensky Holdings, Innovation Fund, International Institute of Tropical Agriculture (IITA), Italian/South African Governments Agreement, Mellon Foundation, Mondi Business paper South Africa and Mondi Shanduka, Mountain to Ocean (MTO) Forestry, National Bioinformatics Network, National Research Foundation (NRF), Norway/South African Governments Agreement, PlantBio - National Innovation Centre in Plant Biotechnology, Potatoes South Africa, Protein Research Foundation, Rockefeller Foundation, SAFCOL/Komatiland Forestry, Sappi, SIDA/South African Government Agreement, South African Avocado Growers Association, South African Litchi Growers Association, South African Mushroom Farmers Association, South African Wattle Growers Union (SAWGU), Tanzanian Government, Technology and Human Resources and Industry Programme (THRIP), Tuscan Namibia/DAAD (Germany), TWK, UP Research Development Fund, Wheat Cereal Trus