MUTATION THAT AFFECTS BIOCHEMICAL PATHWAYS
1);- Drug Resistance Mutation
2):- Enzyme Regulation
3):- Phase Variation
Amongst the mutations that have been most studied are those in which the organism loses the ability to synthesis an essential metabolite. Many organisms e.g. E. coli an grow in simple defined culture media because they have genes for the Production of all the enzymes they require for the synthesis from simple nutrient of all the large variety of organic compounds essential for the construction and functioning of their cells. These are called prototrophic cells. Mutants that can no longer synthesize a particular essential metabolite, such as an amino acid, and are Unable to grow in a medium that does not contain the essential amino acid are called auxotrophic mutants. Studies of mutants blocked at different stages in a synthetic pathway (i.e. with mutations affecting different enzymes in the pathway) are very valuable in the elucidation of biosynthetic pathways.