Progress Report and Major Results
During the past few years, specific research projects designed to develop biotechnology-related agricultural programs have made significant progress in four key research areas, briefly described as follows.
A. Integrative Plant Stress Biology (iPSB)
Six PI laboratories coordinating effectively in projects have obtained encouraging results in screening, characterization and use of drought-, chill-, heat-, heavy metal- or pathogen-tolerant genes, using DNA micro-array, bio-informatics, functional analysis and genetic engineering approaches. Important scientific papers were published and patent applications filed.
New research initiatives into lycopenes and flavanoid phytocompounds of tomato for nutritional and health care studies are being actively pursued in coordination with the herbal medicine research group
B. Herbal Medicine Research (HMR)
Five collaborating research laboratories have defined and established experimental systems for herbal medicine or natural product research. These include the studies of dendritic cell and T-cell related immunomodulatory bioactivities in response to phytocompounds/botanical substances extracted from Dioscorea, Echinacea, and Bidens plants. Functional genomic, proteomic and metabolomic experiments have yielded significant and interesting results, generating scientific paper publications and patent applications.
We have established various in vitro, ex vivo and in vivo technology systems to evaluate the effect of plant crude extracts and/or phytochemicals on antixidants, anti-inflammation and anti-tumor activity.
Mid- and long-term plans of this research program include the use of cDNA microarray, functional genomics, proteomics, and bioinformatics technologies to analyze the plant extract- or phytocompound-responsive genes or protein expression profiles in terms of tumor cell apoptosis or immune-cell activation/suppression.
Secondary metabolite profiles (metabolomics) in medicinal herbal plants and key phytocompound groups responsible for the observed bio-pharmacological activities in animal models or human cell systems are being characterized.
Traditional herbal dietary supplements or the derived phytocompounds for augmentation of the immune system against the SARS virus in Taiwan are being evaluated.
C. Molecular Vaccine Technology (mVT)
Four laboratories have collectively defined specific epitope targets of the foot and mouth disease (FMD), PRRS and SARS viruses for developing DNA or protein/subunit vaccines, and very recently on use of virus-like particles (VLP) as advanced gene-based vaccines.
Cytokine and genetic adjuvants such as CpG-ODN have been shown to enhance the immunogenecity of our test viral antigens. The effect of CpG-DNA on the human immune systems and its potential use as a vaccine adjuvant are evaluated.
We will continue our studies on developing advanced vaccine technologies, e.g., the use of VLP (virus like particle), and new adjuvants, new delivery systems for SARS or bird flu vaccine development.
Gene gun or non-viral gene deliveries, DNA shuffling, and site- or region-specific mutagenesis approaches are being employed to create novel vaccines or improved industrial enzymes.
D. Enzyme Biotechnology (EB)
1,3-1,4-β-D-Glucanase (lichenase, EC 220.127.116.11), a hemicellulase, has received much attention in both basic and applied research because of its enzymatic functions and importance in industrial applications. Important amino acid residues involved in the catalysis, thermostability, and metal ion binding of Fibrobacter succinogenes 1,3-1,4-β-D-glucanase (Fsβ-glucanase) have been characterized using rational design approach.
TFβ-glucanase, a truncated form of Fsβ-glucanase, has been successfully generated and expressed in Pichia host cells, exhibiting a 32-fold higher specific activity than a commercial lichenase.
The novel truncated TF-glucanase retains ~65-88% of its original enzymatic activity after a 30-min incubation at 90-100 ℃. This novel engineered enzyme is US and ROC patents issued, and a couple of technology licensing to local biotech companies were proceeded.
We are also the first team, as a collaborative effort, to elucidate the 3-D structure of the TF-glucanase protein and its complex with the product β-1,3-1,4-cellotriose. The theory for the substrate specificity to 1,3-1,4-β-D-glucan of the enzyme is elucidated.