Conservation, Evolutionary: Difference between revisions

Mutations occur spontaneously in each generation, randomly changing the amino acid sequences of proteins. Individuals with mutations that impair critical functions of proteins may have resulting problems that make them less able to reproduce. Harmful mutations are lost from the gene pool because the individuals carrying them reproduce less effectively. Over time, only harmless (or very rare beneficial) mutations are maintained in the gene pool. This is [[Evolution|evolution]].

When the sequences of a given protein are compared between [http://en.wikipedia.org/wiki/Taxa taxa], using multiple sequence alignment (MSA), differences between sequences most often represent mutations that were allowed (by evolution) to persist because they were harmless. Where the sequences are identical, we say that sequence was '''conserved'''. Such '''evolutionary conservation''' occurs because mutations of these amino acids were harmful to protein function, and were lost over time. Amino acids that are conserved are those most critical to the function of the protein. Thus, looking for evolutionarily conserved patches of amino acids in a 3D protein structure is a good way to '''locate functional sites'''.