Genetic EngineeringGenetic Engineering

Aulanni’amAulanni’amBiochemistry LaboratoryBiochemistry LaboratoryChemistry DepartmentChemistry DepartmentBrawijaya UniversityBrawijaya University

aulani@brawijaya.ac.idaulani@brawijaya.ac.id

What is genetic engineering?

The transfer of genes (segment of DNA) from one species to another.

This is impossible in naturally breeding.

How to get the gene from species A to species B?

A vectorvector is used to carry the gene into the host nucleus.

What are vectors commonly used What are vectors commonly used in GE?in GE?

Plasmid (of bacteria)Plasmid (of bacteria) Viruses Viruses Shotgun technique (blindly shoots tiny Shotgun technique (blindly shoots tiny

particles coated with the gene into the particles coated with the gene into the host cells) host cells)

What is a plasmid?What is a plasmid?

Natural role of a plasmid in Natural role of a plasmid in bacteria?bacteria?

Plasmids usually contain one or two gene that Plasmids usually contain one or two gene that confer a selective advantage on the bacterium e.g. confer a selective advantage on the bacterium e.g. antibiotic resistance geneantibiotic resistance gene. .

Every plasmid possess a Every plasmid possess a replicator genereplicator gene can can duplicated independently from the chromosomal duplicated independently from the chromosomal DNA. DNA.

1&2 : antibiotic resistance genes

3: replicator gene

Recombinant DNA technology

Cut insulin production gene from a human DNACut insulin production gene from a human DNA Paste it into the DNA of Escherichia coliPaste it into the DNA of Escherichia coli The E. coli reproduces rapidly to produce large The E. coli reproduces rapidly to produce large

numbers: numbers: gene cloninggene cloning

restriction enzyme

In bacteria, restriction enzymes are found naturally.

They cut DNA at specific sites.

DNA double helixes are cut at the axis of symmetry:

Cut plasmid

(by adding restriction enzyme)

Cut insulin gene from human cell

(by adding restriction enzyme)

adding ligase enzyme

Insulin gene has been inserted into the plasmid

Place the recombinant plasmids back into the bacteria

Leave the bacteria to grow and multiply

How do I know which bacteria will have How do I know which bacteria will have the plasmid?the plasmid?

Add specific antibiotics to the agar cultureAdd specific antibiotics to the agar culture All those bacteria which do not have the plasmid All those bacteria which do not have the plasmid

will diewill die Only those with the recombinant plasmids can Only those with the recombinant plasmids can

grow and multiplygrow and multiply

Application of GE:Application of GE:

MedicalMedical

GM Food

Industrial production

Environmental protection

MedicalMedical

Production of pharmaceuticals for treatment of Production of pharmaceuticals for treatment of diseases e.g. human insulin, interferonsdiseases e.g. human insulin, interferons

Production of pharmaceuticals for disease prevention e.g. vaccine (hepatitis B vaccine)

MedicalMedical Gene therapy:Gene therapy:

Artificially replace the disease-Artificially replace the disease-causing gene with a normal allele.causing gene with a normal allele.

The normal allele can be carried by a The normal allele can be carried by a virus vector to the target tissues.virus vector to the target tissues.

e.g. treatment of cystic fibrosise.g. treatment of cystic fibrosis

MedicalMedical

Clonal propagation: Clonal propagation: a source of tissue or organ for transplantationa source of tissue or organ for transplantationavoid all problems of immunoincompatibility.avoid all problems of immunoincompatibility.

AgriculturalAgricultural

Transgenic plants and farm animalsTransgenic plants and farm animals

pest-resistant (reduce use of pesticides),pest-resistant (reduce use of pesticides),

increase yieldincrease yield

Increase storage time e.g. green tomato

tomato with beef genes

Industrial:Industrial:

Use of GM microorganisms to make Use of GM microorganisms to make stone-wash jeansstone-wash jeans

Use of GM microorganisms to produce enzymes e.g. detergents

Environmental protectionEnvironmental protection

GM E. coli possesses gene to break down GM E. coli possesses gene to break down cellulose, speeding up recycling of the cellulose, speeding up recycling of the most abundant biomass on earthmost abundant biomass on earth

GM microorganisms with enhanced ability to break down environmental pollutants

Dispute in the development of GMDispute in the development of GM

Dangerous pathogens formed in the course Dangerous pathogens formed in the course of rDNAof rDNA

New tools for militarists and terroristsNew tools for militarists and terrorists Triggering of catastrophic ecological Triggering of catastrophic ecological

imbalance imbalance Moral problems in the use of GM techniques Moral problems in the use of GM techniques

in man e.g. germ cell gene therapyin man e.g. germ cell gene therapy Unknown effect of GM food on menUnknown effect of GM food on men