title: Investigating the role of the hydroxyl groups of substrate erythrose 4-phosphate in the reaction catalysed by the first enzyme of the shikimate pathway.
abstract: 3-Deoxy-D-arabino-heptulosonate 7-phosphate (DAH7P) synthase catalyses the first step of the shikimate pathway, which is responsible for the biosynthesis of aromatic amino acids in microorganisms and plants. This enzyme catalyses an aldol reaction between phosphoenolpyruvate and D-erythrose 4-phosphate to generate DAH7P. Both 2-deoxyerythrose 4-phosphate and 3-deoxyerythrose 4-phosphate were synthesised and tested as alternative substrates for the enzyme. Both compounds were found to be substrates for the DAH7P synthases from Escherichia coli, Pyrococcus furiosus and Mycobacterium tuberculosis, consistent with an acyclic mechanism for the enzyme for which neither C2 nor C3 hydroxyl groups are required for catalysis. The enzymes all showed greater tolerance for the loss of the C2 hydroxyl group than the C3 hydroxyl group.
authors: Biomolecular Interaction Centre and Department of Chemistry, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
authors: David
authors: D
authors: Tran
authors: Amy L
authors: AL
authors: Pietersma
authors: Linley R
authors: LR
authors: Schofield
authors: Matthias
authors: M
authors: Rost
authors: Geoffrey B
authors: GB
authors: Jameson
authors: Emily J
authors: EJ
authors: Parker
mesh_terms: D010723:3-Deoxy-7-Phosphoheptulonate Synthase / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology*; D008958:Models, Molecular; D009169:Mycobacterium tuberculosis / Q000201:enzymology*; D020027:Pyrococcus furiosus / Q000201:enzymology*; D012765:Shikimic Acid / Q000378:metabolism; D013379:Substrate Specificity; D013403:Sugar Phosphates / Q000737:chemistry / Q000378:metabolism*
chemical_list: D013403:Sugar Phosphates; D012765:Shikimic Acid; C026959:erythrose 4-phosphate; D010723:3-Deoxy-7-Phosphoheptulonate Synthase