The boom in industrialization has contributed to the increase of contaminants in the environment.Chromium, in particular, a toxic metal, which in its hexavalent form is an agent that is capable of provoking damage at the cellular level.There are microorganisms with the capacity to reduce this metal to a less toxic mobile form (chromium III) as is the case of E. coli.A comparative study was conducted between some of the reductive proteins of chromium in the E. coli bacteria (YieF, NemA y NfsA), as well as the construction of a protein-protein interactive network aided by Cytoscape 3.3.0software.This allowed the observation of variances in the characteristics related with the reduction of cromato Felicitated d by these enzymes.