3-dehydroquinate dehydratase (DHQD)

3-dehydroquinate dehydratase (DHQD) is a hydro-lyase enzyme (EC 4.2.1.10) that catalyzes the dehydration of 3-dehydroquinate to 3-dehydroshikimate, the third step in the shikimate pathway, which leads to the biosynthesis of aromatic amino acids such as phenylalanine, tyrosine, and tryptophan. This pathway is present in bacteria, fungi, plants, and some parasites, but absent in animals, making DHQD a strong candidate for selective antimicrobial and herbicidal targeting. Two distinct types of DHQD exist (Type I and Type II), differing in structure and catalytic mechanism, but catalyzing the same overall reaction. Its inhibition disrupts microbial and plant viability without affecting mammals, which must obtain aromatic amino acids from their diet.

Other names

3-dehydroquinate hydrolaseDHQasedehydroquinate dehydratase3-dehydroquinase5-dehydroquinasedehydroquinase5-dehydroquinate dehydratase5-dehydroquinate hydro-lyase3-dehydroquinate hydro-lyase

Inhibition of this enzyme blocks biosynthesis of aromatic amino acids in microorganisms and plants, resulting in growth arrest or death; mechanisms vary by inhibitor (e.g., covalent, competitive, or allosteric)