Microorganisms that produce enzymes active on biodegradable polyesters are ubiquitous

Selection of Putative Polyester Hydrolases from the Metagenome of Los Humeros Geothermal Field by Means of In Silico Probes

“…Polyesters are polymers composed of monomers linked by ester bonds [18]. Plastics are polymers synthetized industrially from fossil fuels, such as polycaprolactone (PCL), or obtained from natural sources such as polyhydroxyalkanoates (PHAs), and might be biodegradable or recalcitrant, depending on their chemical composition and physical and physico-mechanical properties [19]. Biodegradable plastics are polyesters that can be degraded by hydrolysis and then recycled and reused [20]; however, the rate of recycling or incineration is well below the level of production, so it is estimated that more than half ends up in landfills or in the environment [21].…”

“…In recent years, various microorganisms able to hydrolyze polyesters such as poly(butylene succinate (PBS), poly(butylene adipate-co-terephtalate) (PBAT), poly(lactic acid) (PLA), poly(εcaprolactone) (PLA) and poly(ethylene terephthalate) (PET) have been isolated from soil, marine seawater, compost, water, sediments, activated sludges, plant leaves and PET residues and characterized. Some of the bacterial and fungal genera reported are Bacillus, Pseudomonas, Marinobacter, Clostridium, Rhodococcus, Thermomonospora, Peribacillus, Priestia, Streptomyces, Acinetobacter, Brevundimonas, Ideonella, Exiguobacterium, Fusarium, Alcanicorax, Thermobifida, Humicula, Rhizopus, Candida, Aspergillus, Penicillium and Moniliophthora; some of the carboxyl esterases identified in the isolates are arylesterases, PETases and MHETases like enzymes, PBAT hydrolases, cutinases, lipases, PCL depolymerases and MHET hydrolases [19,26,27].…”

“…The sequences of genes that code for polyester hydrolases and other enzymes of biotechnological interest have also been obtained by direct sequencing of metagenomic environmental samples from human-affected and relatively pristine sites [28], marine sediments [29], industrial effluents [30], industrial sludge [15] and hot spring sediments and have been identified by homology analysis with sequences present in databases [31]. In addition, candidate genes for polyester hydrolases have been identified in metagenomes from both marine and terrestrial environments by using bioinformatics tools such as search algorithms, identification of conserved sequence motifs and phylogenetic analyses in various databases [19,28,32]. Unfortunately, some of these tools and databases can be expensive and might need powerful hardware or computational resources that are not always available to researchers.…”