extremozymes

Extremozymes are enzymes produced by microorganisms that inhabit extreme environments, such as very high or low temperatures, extreme pH, high salinity, or high pressure. These enzymes maintain catalytic activity and structural stability under conditions that denature most other proteins, making them valuable for industrial and environmental applications.

Extremozymes span several functional groups and environmental adaptations. Thermozymes, from thermophiles and hyperthermophiles, operate at elevated temperatures and often retain activity at temperatures tolerable for industrial processes. Psychrozymes are active at near-freezing temperatures. Enzymes from acidophiles, alkaliphiles, halophiles, and barophiles extend activity to extreme pH, salinity, and pressure. Notable examples include thermostable DNA polymerases such as Taq polymerase from Thermus aquaticus and Pfu polymerase from Pyrococcus furiosus, which are widely used in molecular biology. Proteases, lipases, amylases, and other enzymes from extremophiles are also employed in detergents, food processing, and biocatalysis under harsh conditions.

Sources and discovery rely on organisms from hot springs, deep-sea hydrothermal vents, salt-rich environments, acidic mines, and other extreme ecosystems. Advances in metagenomics and protein engineering have accelerated the identification and optimization of extremozymes, while heterologous expression in conventional hosts can be challenging due to folding, post-translational modifications, or codon usage differences.

Applications of extremozymes include industrial biocatalysis under high temperatures, high salinity, or non-aqueous solvents; production of biofuels and value-added chemicals; environmental remediation of pollutants; and improvements in detergents and food processing. Ongoing research aims to expand the repertoire of extremozymes and to improve their stability and performance through protein engineering.