Catalyzes the second step in the shikimate pathway. 7-phospho-2-dehydro-3-deoxy-D-arabino-heptonate = 3-dehydroquinate + phosphate Metabolic intermediate biosynthesis; chorismate biosynthesis; chorismate from D-erythrose 4-phosphate and phosphoenolpyruvate: step 2/7. Homodimer. Highly expressed in roots. Lower expression in stems, flowers and cotyledons. Barely detected in leaves. Up-regulated by elicitor. Belongs to the sugar phosphate cyclases superfamily. Dehydroquinate synthase family.