This is the second shikimate dehydrogenase enzyme found in Escherichia coli. It can use both quinate and shikimate as substrates and either NAD+ or NADP+ as acceptor. The low catalytic efficiency with both quinate and shikimate suggests that neither may be the physiological substrate. cf. EC 1.1.1.24, quinate/shikimate dehydrogenase (NAD+), EC 1.1.5.8, quinate/shikimate dehydrogenase (quinone), and EC 1.1.1.25, shikimate dehydrogenase (NADP+).
Benach J, Lee I, Edstrom W, Kuzin AP, Chiang Y, Acton TB, Montelione GT, Hunt JF.
Title
The 2.3-A crystal structure of the shikimate 5-dehydrogenase orthologue YdiB from Escherichia coli suggests a novel catalytic environment for an NAD-dependent dehydrogenase.
