| 摘要 |
The present invention relates to mutant alcohol dehydrogenase enzymes, microorganisms comprising same, and methods for the production of one or more products by microbial fermentation. More specifically, the present invention relates to a Clostridium autoethanogenum alcohol dehydrogenase comprising at least one amino acid substitution selected from the group consisting of: Gly198Asp, Gly198Ile, Gly198Leu, Gly198Val, Ser199Asp, Ser199Glu, Ser199Leu, Ser199Val, Arg200Glu, Pro201Asp, Pro201Glu, Tyr218Ala, Tyr218Phe, Tyr218Gly, Tyr218Ser and Tyr218Val; wherein the mutant alcohol dehydrogenase has increased specificity for at least one first substrate over at least one second substrate, wherein: the first substrate is acetone and the second substrate is MEK; the first substrate is acetone and the second substrate is acetaldehyde; the first substrate is acetone and the second substrate is acetoin; the first substrate is MEK and the second substrate is acetaldehyde; the first substrate is MEK and the second substrate is acetoin; the first substrate is acetoin and the second substrate is acetone; the first substrate is acetoin and the second substrate is MEK; the first substrate is acetoin and the second substrate is acetaldehyde; the first substrate is acetaldehyde and the second substrate is acetone; the first substrate is acetaldehyde and the second substrate is acetoin; or, the first substrate is acetaldehyde and the second substrate is MEK. The invention also provides recombinant microorganisms comprising a nucleic acid encoding said Clostridium autoethanogenum alcohol dehydrogenase, methods of making said recombinant microorganisms and methods for the production of one or more of isopropanol, ethanol, 2,3-butanediol, 2-butanol, acetoin, MEK, acetaldehyde, and acetone using said recombinant microorganisms. |
