Principles of Biotechnology

• The two core techniques that developed modern biotechnology are:

(i) Genetic engineering which is modification of chemical nature of DNA/RNA and their introduction into another host organism to change the phenotypic characters of the host.

(ii) Sterilisation methods to maintain growth and manipulation of only the desired microbes or cells in large quantities, for the manufacture of biotechnological products like antibiotics, vaccines, enzymes, etc.

• The basis steps in genetic engineering include:

(i) Identification of DNA with desirable genes.

(ii) Introduction of the DNA into host to form recombinant DNA (rDNA).

(iii) Maintenance of DNA in host and gene cloning.

(iv) Gene transfer.

• Steps carried out in constructing first recombinant DNA:

(i) A gene encoding antibiotic resistance in the native plasmid of Salmonella typhimurium V. was identified. Plasmid is an autonomously replicating circular extra-chromosomal DNA.

(ii) The desired DNA was cut at specific locations by restriction enzymes.

 (iii) The cut DNA was linked to plasmid DNA and transferred to E. coli for gene multiplication.