Endophytic Bacteria and their Potential Application to Improve the Phytoremediation of Contaminated Environments

Abstract

Endophytic bacteria seem to have a ubiquitous existence in most, if not all, higher plant species without causing disease symptoms. Therefore, they seem to be ideal to complement certain metabolic properties of their host plant, such as the fixation of nitrogen or the detoxification of contaminants. This review describes the ecology of endophytic bacteria and a number of natural beneficial interactions between endophytic bacteria and their plant host, such as diazotrophy. It also exploits the possibilities of using endophytic bacteria as carriers of new metabolic properties, which should assist the host plant in degrading organic contaminants or detoxifying heavy metals that presently cause a problem for phytoremediation. Finally, we will discuss the potential of horizontal gene transfer as a tool to adapt the metabolic capability of the endogenous endophytic community to better deal with specific environmental contaminants.