Alcohol Dehydrogenase of Thermococcus hydrothermalis: Native Enzyme Characterization, Cloning, Sequencing and Overexpression of Gene
Elisabeth ANTOINE, Jean-Luc ROLLAND, Christine LADRAT, and Jacques DIETRICH*
Laboratoire de Biotechnologie des Micro-organismes Hydrothermaux, Ifremer, DRV/VP, B.P. 70, 29280 Plouzan, France
An alcohol dehydrogenase activity has been found in crude extract of cultured cells of the new hyperthermophilic archaeon Thermococcus hydrothermalis (1). The native enzyme has been purified and characterized. A degenerated nucleotidic probe was designed according the N-terminal sequence of the amino-acid chain. This probe was used to screen a genomic library of T. hydrothermalis and the Adh gene was sequenced. The obtained gene was cloned in an expression system (Quiagen expression cloning vector pQE30) and overexpression of the recombinant enzyme is now under progress.
Within the archaea, the third domain of life, so far only a few number of alcohol dehydrogenases have been characterized. There is considerable interest in alcohol dehydrogenases from hyperthermophiles, since they are potential alternatives for less thermostable and chemically stable enzymes that are currently used as industrials biocatalists.
1. Godfroy, A., Lesongeur, F., Raguenes, G., Querellou, J., Antoine, E., Meunier, J.R., Guezennec, J., and Barbier, G. (1997) Int. J. Syst. Bacteriol., 47, 622-626.
