Microbiology and Immunology

WORLD OF MICROBIOLOGY AND IMMUNOLOGY Genetic code

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Genetic code related to models of amino acids inserting into a protein.

triplets have some meaning within the code and that several

codons may encode a single amino acid.

This work confirmed the ideas of the British scientists

Francis Crick(1916– ) and Sidney Brenner(1927– ). Brenner

and Crick were working with mutationsin the bacterial virus

bactriophage T4 and found that the deletion of a single

nucleotide could abolish the function of a specific gene.

However, a second mutation in which a nucleotide was

inserted at a different, but nearby position restored the function

of that gene. These two mutations are said to be suppressors of

each other, meaning that they cancel each other’s mutant prop-

erties. It was concluded from this that the genetic code was

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