Two useful microbes of biotechnology are :
(a) Bacillus thuringiensis : A gene has been isolated from this microbe. The gene is introduced into cotton plants, resulting in the production of a toxin by cotton plants, which kills the harmful nematode.
(b) Escherichia coli : It is a microbe, which is used in many biotechnological processes. Plasmid of this bacterium is used as a vector for transfer of foreign DNA into desired organism.