Biotechnology and Medicinal Plants Flashcards
Artificial Culture Advantages
Synthesise materials that are too expensive, rare, political and/or seasonal to be used in dosage forms. Artificial production of materials may synthesise new materials (therapeutic benefits). also produces genetically altered products (eg soy beans)
Plasticity in Plant Cells Outline
Plants change metabolism, growth or development to best suit their development. Organs can regenerate from any tissues. Cells cultured in vitro are more plastic
Totipotency Def
Cells are able to divide and differentiate into any cell type.
Plant culture method
Source tissue from root/shoot. Tissue should form callus (jelly undifferentiated cells). Transfer callus to liquid medium and agitate forming a suspension (batch, semicontinuous, continuous). Transfer callus to adjusted medium to develop organs
Generic Media Composition
Carbon source, macroelements, microelements, amino acids, vitamins and hormones. Light and temp must be considered. Conditions must be sterile
Synthetic Manipulation of Tissue
Precursors, hormones and elicitors
Precursor Def
Additional chemicals in media that allows further selectivity and differentiation of cells
Elicitor/Phytoalexins Outline
Chemicals that stimulate biological change in cell eg specific metabolite production
Plant Growth Kinetics
Lag, log, deceleration and stationary
Plant Growth Timelines
1-30 days (as opposed to bacterial in seconds)
Optimisation Methods
Selection of high yielding cultures. Visual/fluroesence microscopy, cell lines and optimisation of media and growing conditions
Biocatalyst Outline
cells in pelleted alginate, PU foam and acrylamide
Biochemical Conversions In Nature
Glycosylation (adding of sugar), hydroxylation (adding of OH ) and acetylation (transfer CH3)
Plant Cell Cultures Disadvantages
Slow, aggregate together (without aggregation), cells fragile to shear forces, difficult to isolate, new metabolites (toxic). Potentially reduced expression as not all variable in nature are present in culture
Organ Cultures Outline
Aseptic suspensions of leaves/roots. May synthesise secondary metabolites in cultures. Induced callus differentiation and use sterile growing points
Genetic Manipulation In Cultures
Intro foreign genes or specifically designed hybrid genes into host plant genus. Alters metabolism products
Application Of Gene Manipulation
Therapuetic antibodies (eg monoclonal antibodies), edible vaccines and other therpuetic agents (hormones, blood components, coagulation factors and interferons)
Plant Genetic Transformation Outline
Change in plant genetic code
Hairy Root Cultures
Change in plant genetic code by bacteria. Soil bacteria (agrobacterium) insert their own genes into plant cells in nature. Fast, hormone free, genetically/biochemically stable, can be used to isolate metabolites.
Restriction Enzymes Outline
Enzyme that recognises sequences on DNA and makes double helix cuts at relevant sites of action. Function in bacteria: destroy foreign DNA
Palindrome Def
Sequence in DNA that restriction enzymes recognise. Each enzyme only recognises 1 sequence
How fragments of DNA stick together
Sequences cut by the same restriction enzyme have complimentary ends. Attach together and DNA ligase sticks them togtehr
Plasmid Outline
Extrachromosomal closed circular DNA molecules. Replicate independent of chromosome. Genes control fertility and antibiotic resistance
Vector Outline
Plasmid that has integrated foreign DNA into it’s loop
Molecular cloning
Plamid accepts foreign DNA and becomes a vector. Vector replicates
Leaf Disk Plant Transformation
Agrobacterium contains a Ti plasmid. When co-cultivated with plant cells the agrobacteria transfer the DNA. Disc on nutrient kedium produce metabolites to kill non-transformed plants (selective - less competition). Every cell in culture should have desired genes. Cell pass genes onto offspring
Examples of cultured plant cells
alakaloids (eg berberine), ginsenoids and taxol (anticancer)
