Methods for the fermentive production of four carbon alcohols are provided. Specifically, butanol, preferably 2-butanol is produced by the fermentive growth of a recombinant bacteria expressing a 2-butanol biosynthetic pathway. The recombinant microorganisms and methods of the invention can also be adapted to produce 2-butanone, an intermediate in the 2-butanol biosynthetic pathways disclosed herein. Specifically disclosed herein are the use of coenzyme B12-independent butanediol dehydratases that catalyzes the substrate to product conversion of 2,3-butanediol to 2-butanone in the process of producing 2-butanol and 2-butanone.
