Enzymes from Extreme Thermophilic and Hyperthermophilic Archaea and Bacteria

Hyperthermophilic aldolases as biocatalyst for C–C bond formation: rhamnulose 1-phosphate aldolase from Thermotoga maritima

“…These organisms have adapted to live in extreme environments offering useful enzymes that should enable us to expand the range of reaction conditions suitable for biocatalysis. In particular, thermophiles (an optimal growth temperature of between 50 and 80 °C) and hyperthermophiles (an optimal growth temperature of between 80 and 110 °C) have attracted attention from a biocatalytical point of view since these microorganisms are a source of thermostable enzymes (thermozymes) that display an outstanding stability against high temperatures and, furthermore, it has also been reported that these enzymes show enhanced tolerance against other denaturalization conditions such as the presence of organic solvents, detergents or extreme pHs (Atomi et al 2011;Bertoldo and Antranikian 2008;Atomi 2005;Vieille and Zeikus 2001). Moreover, carrying out reactions at high temperatures brings other advantages, such as that it allows for the use of higher concentrations of substrates, to decrease the viscosity of the reaction medium, to prevent against possible microbial contamination and frequently leads to higher reaction rates.…”

Noteworthy Facts about a Methane-Producing Microbial Community Processing Acidic Effluent from Sugar Beet Molasses Fermentation

“…Among the identified archaeal sequences some were assigned to non-methanogens: Halobacteriaceae— aerobic heterotrophs able to grow anaerobically [ 55 ]; Thermoplasmata— facultative anaerobes capable of sulfur respiration [ 56 ] ; Thermococcales —anaerobes able to utilize proteins and carbohydrates [ 57 ]; Archaeoglobus— another anaerobe and known sulfate-reducer capable of oxidizing lactate to carbon dioxide [ 58 ]. The origin of the inoculum can explain the presence of these Archaea in the community.…”