Hyperthermophiles hyperthermophilic

In another study a hyperthermophilic esterase from Aeropyrum pemix K1 (APE1547) was used as a catalyst in the hydrolytic kinetic resolution of rac-3-octanol acetate [53]. Following a single round of epPCR, a mutant displaying a 2.6-fold increase in enantioselectivity was identified having five amino acid substitutions, which were shown to be spatially distal to the catalytic center. 

Very recently a new type of 7Fe Fd (Mr 12,000) has been purified from the hyperthermophilic archaeon Pyrobaculum islandicum 122). The protein has a C-terminal extension, as in A. vinelandii Fdl, but the overall sequence homology between these two Fds is low, and the... 

Childers SE, DR Lovley (2001) Differences in Ee(lll) rednction in the hyperthermophilic archaeon Pyrobacu-lum islandicum, versns mesophilic Fe(Ill)-redncing bacteria. FEMS Microbiol Lett 195 253-258. 

Kjellberg S, M Hermansson, P Marden, GW Jones (1987) The transient phase between growth and nongrowth of heterotrophic bacteria with emphasis on the marine environment. Annu Rev Microbiol 41 25-49. Klump H, J Di Ruggiero, M Kessel, J-B Park, MWW Adams, FT Robb (1992) Glutamate dehydrogenase from the hyperthermophile Pyrococcus furiosus. Thermal denaturation and activation. J Biol Chem 267 22681-22685. 

Mukund S, MWW Adams (1991) The novel tungsten-iron-sulfur protein of the hyperthermophilic archaebacterium, Pyrococcus furiosus, is an aldehyde ferredoxin oxidoreductase. J Biol Chem 266 14208-14216. 

Mukund S, MWW Adams (1995) Glyceraldehyde-3-phosphate ferredoxin oxidoreductase, a novel tungsten-containing enzyme with a potential glycolytic role in the hyperthermophilic archaeon Pyrococcus furiosus. J Biol Chem 270 8389-8392. 

Roy R, S Mukund, GJ Schut, DM Dunn, R Weiss, MWW Adams (1999) Purification and molecular characterization of the tungsten-containing formaldehyde ferredoxin oxidoreductase from the hyperthermophilic archaeon Pyrococcus furiosus the third of a putative five-member tungstoenzyme family. J Bacteriol 181 1171-1180. 

Vadas A, HG Monbouquette, E Johnson, I Schroder (1999) Identification and characterization of a novel ferric reductase from the hyperthermophilic archaeon Archaeoglobus fulgidus. J Biol Chem 274 36715-36721. 

The sulfite reductase from the hyperthermophilic methanogen Methanocaldococcus jannashii is able to reduce the otherwise toxic sulfite to sulfide that is required for growth. In contrast to most organisms that use nicotinamides and cytochromes as electron carriers, this organism uses a coenzyme p42o-dependent reductase (Johnson and Mukhopadhyay 2005). 

Roy R, MWW Adams (2002) Characterization of a fourth tungsten-containing enzyme from the hyperthermophilic Pyrococcus furiosus. J Bacterial 184 6952-6956. 

Isotope fractionation during sulfate reduction by the hyperthermophilic Archaeoglobus fulgidus varied with the concentration of sulfate, and it was suggested that different pathways were operative at concentrations >0.6 or <0.3 mM (Habicht et al. 2005). 

Moracci, M., Cobucci-Ponzano, B., Perugino, G. et al. (2005) Recent developments in the synthesis of oligosaccharides by hyperthermophilic glycosidases, in Handbook of Carbohydrate Engineering (ed. K.J. Yarema), CRC Press LLC, Boca Raton, FL, pp. 587-612. 

Albers, S.V., Jonuscheit, M., Dinkelaker, S. et al. (2006) Production of recombinant and tagged proteins in the hyperthermophilic archaeon Sulfolobus solfataricus. Applied and Environmental Microbiology, 72 (1), 102-111. 

Vieille, C. and Zeikus, G.J. (2001) Hyperthermophilic enzymes sources, uses, and molecular mechanisms for thermostability. Microbiology and Molecular Biology Reviews, 65 (1), 1 43. 

De Miguel Bouzas, T., Barros-Velazquez, J. and Villa, T.G. (2006) Industrial applications of hyperthermophilic enzymes a review. Protein Peptide Letters, 13(7), 645-651. 

Zhu, D., Malik, H.T. and Hua, L. (2006) Asymmetric ketone reduction by a hyperthermophilic alcohol dehydrogenase. The substrate specificity enantioselectivity and tolerance of organic solvents. Tetrahedron Asymmetry, 17 (21), 3010-3014. 

A nitrilase from the hyperthermophile Pyrococcus abyssi, which exhibits optimal growth at 100 °C, was cloned and overexpressed. Characterization of this nitrilase revealed that it is operational as a dimer (rather than the more common multimeric structure for nitrilases), with optimal pH at 7.4 and optimal apparent activity at 80 °C with Tm (DSC) at 112.7 °C. The substrate specificity of the nitrilase is narrow and it does not accept aromatic nitriles. The nitrilase converts the dinitriles fumaronitrile and malononitrile to their corresponding mononitriles [58],... 

Mueller, P, Egorova, K., Vorgias, C.E. et al. (2006) Cloning, overexpression, and characterization of a thermoactive nitrilase from the hyperthermophilic archaeon Pyrococcus abyssi. Protein Expression and Purification, 47, 672-668. 

Could it be the case that microorganisms, like the suspected fossils in the Mars meteorite ALH 84001, exist in the Martian soil This question leads to the counterquestion as to whether it has previously been possible to detect and study life (primitive life forms) under highly extreme conditions. Are there such conditions on Earth We now know quite a lot about extremophiles such as the thermophilic, halophilic and hyperthermophilic microorganisms. 

Finally, as a poor man s alternative, consider the possibility to slow down the reaction kinetics by running a reaction at < 0°C temperatures (especially by employing enzymes from hyperthermophilic species) so that the mixing may be done in seconds (by hand ), and let us then hope that the kinetic mechanism under these nonphysiological conditions still bears relevance to the natural biology. 

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