Abstract: The present invention relates to a polypeptide comprising the amino acid sequence of the Bacillus subtilis alanine dehydrogenase or a variant thereof, where Leu197 or an amino acid which is located at a homologous position in the amino acid sequence is exchanged for an amino acid with a positively charged side chain, to a nucleic acid molecule encoding such a polypeptide, and to a process for the production of alanine or a compound generated with consumption of alanine, comprising the step of reacting pyruvate with ammonium and NADPH to give alanine by bringing the pyruvate into contact with the polypeptide according to the invention or with the cell according to the invention.