Patent ID: 8828704

Claim:
A recombinant microbial host cell comprising at least one heterologous DNA molecule encoding a polypeptide that catalyzes the substrate to product conversions: i) pyruvate to alpha-acetolactate; ii) alpha-acetolactate to acetoin; iii) acetoin to 2,3-butanediol; and iv) 2,3-butanediol to 2-butanone; wherein the at least one DNA molecule that catalyzes the substrate to product conversion of 2,3-butanediol to 2-butanone encodes a coenzyme B12-independent butanediol dehydratase, and further wherein the B12-independent butanediol dehydratase has an amino acid sequence having at least 75% identity to the amino acid sequence of SEQ ID NO:276 based on the Clustal W method of alignment using the default parameters of GAP PENALTY=10, GAP LENGTH PENALTY=0.1, and Gonnet 250 series of protein weight matrix; and wherein the microbial host cell produces 2 butanol.