Shikimate dehydrogenase (SDH) is the fourth enzyme involved in the shiki-mate pathway. It catalyzes the NADPH-dependent reduction of 3-dehy-droshikimate to shikimate, and has been developed as a promising target for the discovery of antimicrobial agent. In this report, we identified a new aroEgene encoding SDH fromHelicobacter pyloristrain SS1. The recom-binantH.