Lipolytic enzymes catalyze the hydrolysis of ester bonds in the presence of water. In media with low water content
or in organic solvents, they can catalyze synthetic reactions such as esterification and transesterification. Lipases and
esterases, in particular those from extremophilic origin, are robust enzymes, functional under the harsh conditions of industrial
processes owing to their inherent thermostability and resistance towards organic solvents, which combined with
their high chemo-, regio- and enantioselectivity make them very attractive biocatalysts for a variety of industrial applications.
Likewise, enzymes from extremophile sources can provide additional features such as activity at extreme temperatures,
extreme pH values or high salinity levels, which could be interesting for certain purposes. New lipases and esterases
have traditionally been discovered by the isolation of microbial strains producing lipolytic activity. The Genome Projects
Era allowed genome mining, exploiting homology with known lipases and esterases, to be used in the search for new enzymes.
The Metagenomic Era meant a step forward in this field with the study of the metagenome, the pool of genomes in
an environmental microbial community. Current molecular biology techniques make it possible to construct total environmental
DNA libraries, including the genomes of unculturable organisms, opening a new window to a vast field of unknown
enzymes with new and unique properties. Here, we review the latest advances and findings from research into new
extremophilic lipases and esterases, using metagenomic approaches, and their potential industrial and biotechnological