May be involved in H(2) production during fermentative growth. Loss of H(2) production on minimal glucose, complex glucose and complex formate medium. Alters production of organic acids when grown on minimal glucose medium. This phenotype was not complemented by reintroduction of the ypdJ gene. It is missing about 100 C-terminal amino acids compared to orthologs. Encoded by the CPS-53 (KpLE1) prophage.