Metagenomics of Thermophiles with a Focus on Discovery of Novel Thermozymes

Abstract

Microbial populations living in environments with temperatures above 50°C (thermophiles) have been widely studied, increasing our knowledge in the composition and function of these ecological communities. Since these populations express a broad number of heat-resistant enzymes (thermozymes), they also represent an important source for novel biocatalysts that can be potentially used in industrial processes. The integrated study of the whole-community DNA from an environment, known as metagenomics, coupled with the development of next generation sequencing (NGS) technologies, has allowed the generation of large amounts of data from thermophiles. In this review, we summarize the main approaches commonly utilized for assessing the taxonomic and functional diversity of thermophiles through metagenomics, including several bioinformatics tools and some metagenome-derived methods to isolate their thermozymes.

Correlating enzyme annotations with a large set of microbial growth temperatures reveals metabolic adaptations to growth at diverse temperatures

“…Several studies avoid the limitations associated with comparing a small number of thermophilic versus mesophilic species, thereby identifying more general trends, by performing metagenomic analysis of environmental samples from extreme habitats (DeCastro, Rodríguez-Belmonte, and González-Siso 2016;Cowan et al 2015) . A study comparing metagenomes obtained from cold and hot deserts found thermophiles having a higher number of genes involved in metabolism and transport of carbohydrates and secondary metabolites (Le et al 2016) .…”

Metagenomics of microbial and viral life in terrestrial geothermal environments

“…Hot springs populated by extreme thermophiles (T opt : 65-79°C) and hyperthermophiles (T opt [ 80°C) (DeCastro et al 2016) are very diverse and some of them show combinations of extreme chemo-physical conditions, such as temperature, acidic or alkaline pHs, high pressure, and high concentrations of salts and heavy metals (López-López et al 2013). As with all studies of environmental microbiology, our understanding of the composition, functional and physiological dynamics, and evolution of extreme-and hyper-thermophilic microbial consortia has lagged A. Strazzulli Á M. Moracci Á P. Contursi…”

Thermostable enzymes and polysaccharides produced by thermophilic bacteria isolated from Bulgarian hot springs

“…The following groups of thermophiles are commonly suggested based on their optimal growth temperature: moderate thermophiles growing between 50 and 70°C with an optimum of 55-65°C, extreme thermophiles growing optimally at temperatures between 65 and 80°C, and hyperthermophiles with Correspondence: Dr. Margarita Kambourova (margikam@ microbio.bas.bg), Institute of Microbiology, Bulgarian Academy of Sciences, Acad. Such compounds significantly contribute to biotechnological advancements in recent years [4][5][6]. 26, 1113 Sofia, Bulgaria Abbreviation: EPSs, exopolysaccharides optimum growth higher than 80°C [3].…”

“…These microorganisms have developed unique metabolic and physiological capabilities to thrive in extreme habitats and to produce particular metabolites that are rarely present in microbes of modest environments. Such compounds significantly contribute to biotechnological advancements in recent years [4][5][6]. Among compounds involved in thermophilic adaptation, enzymes and exopolysaccharides (EPSs) are of special biotechnological interest due to their unusual stability not only to high temperatures but also to detergents, organic solvents, high salt concentrations.…”