Presentation on theme: "Biotechnology Biotechnology is the use of biological processes, organisms, or systems to manufacture products intended to improve the quality of human."— Presentation transcript:
1 BiotechnologyBiotechnology is the use of biological processes, organisms, or systems to manufacture products intended to improve the quality of human life.
2 Genetic Engineering- (A.K.A. Recombinant DNA Technology) frequency of an allele in a population*involves cutting (cleaving) DNA from one organism into small fragments & inserting the fragments into a host organism of the same or a different species
3 AMAZING!!! Organism will use the foreign DNA as if it were its own!! Transgenic Organism- organisms that contain functional recombinant DNA (rDNA) from a different organism
4 4 Areas of Biotechnology AgricultureIndustryForensicsMedicine
5 Remember DNA? What is the monomer of DNA? How do bases pair? NucleotidesHow do bases pair?A – TC – GWhat kind of bond is used?Hydrogen bonds between nitrogen bases
6 I. Restriction Enzymes AKA Restriction Endonucleases What macromolecule do you think they are made of?They are PROTEINS that cut strands of DNA at specific nucleotide sequences
7 Isolating foreign DNA fragments -Restriction Enzymes- DNA cutting enzymes that can cut both strands of a DNA molecule at a specific base pair sequence (A-T, C-G)-similar to cutting a zipper into pieces-must find the same sequence of base pairs on both DNA strands but they must run in opposite directions
8 Restriction Enzymes (cont.) There are many different restriction enzymes that each cut DNA at different nucleotide sequencesMost will cut the DNA with a staggered cutUsually occurs at a palindrome: a sequence of units that can be read the same way in either direction (ex. Mom, dad, racecar)5‘…GAATTC…3’3‘…CTTAAG…5’
10 D. Sticky EndsThe staggered cuts leave the DNA with end pieces “sticking off”We call these “sticky ends”These exposed N-bases will want to join with other complimentary exposed bases
11 E. Types of Restriction Enzymes Sticky End- already discussedBlunt EndThese cut the DNA straight across and create blunt ends:CCC GGGGGG CCC
12 F. Products generated by restriction enzymes 1. COHESIVE END CUTTERS (staggered cuts):Enzyme Recognition Site Ends of DNA After Cut5’…GAATTC…3’3’…CTTAAG…5’5’…G AATTC…3’3’…CTTAA G…5’EcoRIPst I5’…CTGCAG…3’3’…GACGTC…5’5’…CTGCA G…3’3’…G ACGTC…5’2. BLUNT END CUTTERS (direct cuts):Enzyme Recognition Site Ends of DNA After Cut5’…GG CC…3’3’…CC GG…5’5’…GGCC…3’3’…CCGG…5’HaeIII
13 I = first enzyme isolated G. Restriction Enzyme Naming1. Restriction enzymes are named according to the following nomenclature:Ex: EcoRIE = genus Escherichiaco = species coliR = strain RY13I = first enzyme isolated
14 How is a transgenic organism formed?? Isolate foreign DNA fragmentAttach DNA fragment to a “vehicle” (vector)Transfer “vehicle” (vector) into a host organism
15 Forming transgenic organisms and therefore clones of genes
16 Why would anyone go through the trouble of cutting DNA??? One reason…Recombinant DNABreak down the word…what do you think recombinant means?Other reasons…DNA fingerprinting, gene therapy…
17 II. Recombinant DNARecombinant DNA: DNA that has been cut from one strand of DNA and then inserted into the gap of another piece of DNA that has been broken.The host DNA is often a bacterial cell such as E coli.
18 B. Bacterial StructureBacteria are often used in biotechnology because they have plasmidsA PLASMID is a circular piece of DNA that exists apart from the chromosome and replicates independently of it.A plasmid is therefore called a VECTOR.
19 Vectors transfer DNAVector-means by which DNA from another species can be carried into the host cellMechanical VectorsMicropipette-inserts into a cellGene guns- tiny metal bullet is coated with DNA and shot into the cell with a gene gun
20 More types of Vectors Biological Vectors Viruses Plasmids-small ring of DNA found in bacteria cells that is separate from the bacteria’s normal set of DNAPlasmid usually contains genes that may cause the bacteria to be resistant to certain antibiotics
21 D. Isolating GenesMust isolate the gene of interest first before you insert it into the plasmidHow do you do this?Use a restriction enzyme!!!
22 Final Steps of Making Recombinant DNA Once the gene is isolated, have to cut the organism’s DNA with the same restriction enzyme…why?The sticky ends will naturally be attracted to each otherAdd DNA LIGASE: enzyme that seals the fragments togetherAfter the foreign DNA has been spliced (glued) into the plasmid using an enzyme DNA ligase, the rDNA is transferred into a bacterial cell or other organismNow organism is called a Transgenic Organism- organisms that contain functional recombinant DNA (rDNA) from a different organism
24 Gene Splicing/Cloning using a bacterial plasmid -IMPORTANT plasmid replicates separately from the bacterial chromosome & can produce up to 500 copies per bacterial cell-bacteria reproduce quickly (20 min) so a lot of rDNA is made very fastYou will essentially be cloning a gene- genetically identical copies of rDNA molecules-Host cell produces the protein coded for by the rDNA
26 III. Uses for Recombinant DNA Recombinant DNA has been gaining importance over the last few years, and will become more important as genetic diseases become more prevalent and agricultural area is reduced. Below are some of the areas where Recombinant DNA will have an impact:Better Crops (drought & heat resistance)GMO’s (crops like seedless watermelon, pluots, etc.)Recombinant Vaccines (i.e. Hepatitis B)Production of clotting factorsProduction of insulinProduction of recombinant pharmaceuticalsPlants that produce their own insecticidesGerm line and somatic gene therapy
27 RECAP Steps for making a transgenic organism: Locate and isolate the gene of interestCut out the gene and cut the plasmid using the appropriate restriction enzyme
28 3. Insert the desired gene into the plasmid matching up the sticky ends
29 4. Use the enzyme DNA ligase to seal up the sticky ends
30 5. Transfer the vector in the host organism where it will replicate 6. Host organism produces the protein coded for by the recombinant DNA