Tag: commercial applications of biotechnology

In 1973 Herbert Boyer, of the University of California at San Francisco, and Stanley Cohen, at Stanford University, reported the construction of functional organisms that combined and replicated genetic information from different species. Their experiments dramatically demonstrated the potential impact of DNA recombinant engineering on medicine and pharmacology, industry and agriculture.

Bacteria were the first organisms to be genetically modified. Plasmid DNA containing new genes can be inserted into the bacterial cell and the bacteria will then express those genes. These genes can code for medicines or enzymes that process food and other substrates.

Tissue plasminogen activator is a clot-dissolving enzyme that is produced naturally by cells in the walls of blood vessels and catalyzes the conversion of plasminogen to plasmin. A preparation of this enzyme is produced by genetic engineering and used to dissolve clots blocking coronary arteries in heart attack and cranial arteries in certain cases of stroke.

Genetic engineering is possible because all organisms are based on the same genetic code. DNases which act on specific positions or sequences on the DNA are called as restriction endonucleases. The sequences which are recognised by the restriction endonucleases or restriction enzymes (RE) are called as recognition sequences restriction sites. These sequences are palindromic sequences. Different restriction enzymes present in different bacteria can recognize different or same restriction sites but they will cut at two different points within the restriction site. No two restriction enzymes from a single bacterium will cut at the same restriction site. 

Genetic engineering is the process of replicating a specific set of genes from a strand of DNA. It is the process of using gene cloning and other genetic manipulation tools to achieve isolate specific genes. 

The first generation vaccines consist of live attenuated/ heat killed vaccines in which whole organisms in the weakened live form or heat killed form are injected. Sevcond generation vaccines are those vaccines in which the whole organism is not given. Instead of this a portion called the subunit, which may contain a protein section of the pathogen is given. Third generation vaccines are those in which recombinant techniques are used for the production of vaccines. In this technique DNA encoding the antigen is inserted into a vector which will be recognised as a pathogen in the host. Such that the host immune system generates an immune response against the vector and thereby the antigen. So, the correct answer is 'Third generation vaccines'.

They are three types of vaccines on basis of organism or its part used as antigen.

Smallpox vaccine is produced from the artificially attenuated smallpox virus. The administration of this vaccine ios called as vaccination against smallpox. As on administration of this vaccine, our body develops immunity against the particular virus.