Environmental biotechnology offers several promising techniques for the rehabilitation
of polluted environments. The modern industrialized world presents novel challenges
to the environmental sciences, requiring a constant development and deepening of knowledge
to enable the characterization of novel pollutants and a better understanding of the
bioremediation strategies as well as their limiting factors. The success of bioremediation
depends heavily on the survival and activities of indigenous microbial communities
and their interaction with introduced microorganisms. The majority of natural microbiomes
remain uncultivated; therefore, further investigations focusing on their intrinsic
functions in ecosystems are needed. In this review, we aimed to provide (a) a comprehensive
overview of the presence of viable but nonculturable bacteria and yet-to-be-cultivated
cells in nature and their diverse awakening strategies in response to, among other
factors, signalling extracellular metabolites (autoinducers, resuscitation promoting
factors, and siderophores); (b) an outline of the trends in isolating unculturable
bacteria; and (c) the potential applications of these hidden players in rehabilitation
processes.
