Important terms in Biotechnology: Principles and Processes

 

Biotechnology: Principles and Processes
Genetic engineeringManipulation and alteration of the genetic makeup of organisms using biotechnology

Recombinant DNA (rDNA) is used

An organism with a desired trait is generated

Bioprocess engineeringUse of biotechnology in chemical engineering processes to manufacture products from living organisms in a large quantity

E.g. vitamins, vaccines, antibiotics, etc.

PlasmidExtrachromosomal, circular DNA, which replicates autonomously

E.g. commonly present in bacteria

Recombinant DNA (rDNA)DNA formed by combining DNA pieces or desired genes of two different species or organisms

Stanley Cohen and Herbert Boyer produced the first artificial rDNA by adding antibiotic-resistant genes to the plasmid of Salmonella typhimurium

Restriction enzymesMolecular scissors, restriction endonucleases

They cut the DNA at a specific palindromic sequence forming sticky ends

Werner Arber, Hamilton Smith, and Daniel Nathans discovered

Hind II– the first restriction endonuclease

EcoRIIsolated from E.coli RY13

Recognition site, where the enzyme cuts is G/AATTC (5’→3’) and in the complementary strand it is CTTAA/G (3’→5’)

Discovered in Boyer’s UCSF lab

DNA LigaseJoins the sticky ends of DNA fragments cut by restriction enzymes

Joins Okazaki fragments of lagging strand during replication

Paul BergFather of genetic engineering

Carried out gene-splicing experiments

Added genes of lambda phage virus into DNA of SV-40 virus

Received Nobel prize in 1980

VectorsDNA carriers for transferring the desired gene or DNA fragment into the host

E.g. plasmids (pBR322, Ti), bacteriophages (λ phage)

pBR322E.coli plasmid

Origin of replication- ori

Selectable markers- ampicillin and tetracycline resistant genes, i.e. ampR and tetR

Restriction sites- BamH I, Sal I (in tetR gene), Hind III, EcoR I, Pvu II, Pst I (in ampR gene), Cla I, etc.

Polymerase chain reaction (PCR)In vitro synthesis of multiple copies of genes of interest, invented by Kary Mullis

The oligonucleotide primer is used after denaturation- Annealing

Primer is extended using thermostable DNA polymerase, i.e. Taq polymerase isolated from Thermus aquaticus (bacterium)

Gene transferIntroducing foreign DNA into host cell

Using vector

Without vector- microinjection (direct injection of rDNA into the nucleus of animal cells)

Biolistics or gene gun- plant cells are bombarded with microparticles of gold or tungsten coated with DNA

ElutionThe process of cutting and extracting separated DNA pieces from gel electrophoresis
Downstream processingThe process of separation and purification to make the finished product after biosynthesis

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