Cis-fermentation preparation method of lysine

The invention provides a cis-fermentation preparation method of L-lysine. The method comprises the following steps of: introducing polynucleotide of encoded pyridine nucleotide transhydrogenase variant into an L-lysine generating bacterium so that the obtained bacterium expresses the pyridine nucleotide transhydrogenase variant; and culturing the bacterium under fermentation conditions to obtain a bacterium. In addition, the invention also provides an intermediate product used in the fermentation method and a product further produced by the fermentation method.