Diet as a Pressure on the Amino Acid Content of Proteomes

Whether diet has been influencing the genomic and proteomic constitution of the organisms along the evolution is an interesting and not answered question. Here, we investigate the hypothesis that essential amino acids – the ones that are not produced by the organisms – have being replaced in proteins by non-essential ones. We compare the amino acid composition of the proteome from human, worm and fly, that cannot synthesize all amino acids, with the ones from plant, baker yeast and budding yeast, capable to synthesize all of them. The analysis was made with 190,074 proteins composed of 87,175,891 amino acids. Our data seems to evidence a little bias on the usage of non-essential amino acids by the metazoan organisms, except for the worm. Thus, the preliminary results shown here support the thesis that non-essential ones have replaced essential amino acids.