Economical evolution: microbes reduce the synthetic cost of extracellular proteins.

ABSTRACT: Protein evolution is not simply a race toward improved function. Because organisms compete for limited resources, fitness is also affected by the relative economy of an organism's proteome. Indeed, many abundant proteins contain relatively high percentages of amino acids that are metabolically less taxing for the cell to make, thus reducing cellular cost. However, not all abundant proteins are economical, and many economical proteins are not particularly abundant. Here we examined protein composition and found that the relative synthetic cost of amino acids constrains the composition of microbial extracellular proteins. In Escherichia coli, extracellular proteins contain, on average, fewer energetically expensive amino acids independent of their abundance, length, function, or structure. E

SUBMITTER: Smith DR 

PROVIDER: S-EPMC2932507 | biostudies-literature | 2010 Aug

REPOSITORIES: biostudies-literature