Dihydropteroate synthase
Dihydropteroate synthetase | |||||||||
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ExPASy NiceZyme view | | ||||||||
KEGG | KEGG entry | ||||||||
MetaCyc | metabolic pathway | ||||||||
PRIAM | profile | ||||||||
PDB structures | RCSB PDB PDBe PDBsum | ||||||||
Gene Ontology | AmiGO / QuickGO | ||||||||
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Pterin binding enzyme | |||||||||||
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Identifiers | |||||||||||
Symbol | Pterin_bind | ||||||||||
SCOP2 | 1ajz / SCOPe / SUPFAM | ||||||||||
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Dihydropteroate synthase (DHPS) is an enzyme classified under EC 2.5.1.15. It produces dihydropteroate in bacteria, but it is not expressed in most eukaryotes including humans. This makes it a useful target for sulfonamide antibiotics, which compete with the PABA precursor.
- 4-aminobenzoate(PABA) diphosphate + dihydropteroate.
All organisms require reduced folate cofactors for the synthesis of a variety of metabolites. Most microorganisms must synthesize folate de novo because they lack the active transport system of
Dihydropteroate synthase (EC 2.5.1.15) (DHPS) catalyses the condensation of 6-hydroxymethyl-7,8-dihydropteridine pyrophosphate to para-aminobenzoic acid to form 7,8-dihydropteroate. This is the second step in the three-step pathway leading from 6-hydroxymethyl-7,8-dihydropterin to 7,8-dihydrofolate. DHPS is the target of sulfonamides, which are substrate analogues that compete with para-aminobenzoic acid. Bacterial DHPS (gene sul or folP)[2] is a protein of about 275 to 315 amino acid residues that is either chromosomally encoded or found on various antibiotic resistance plasmids. In the fungus Pneumocystis jirovecii (previously P. carinii) DHPS is the C-terminal domain of a multifunctional folate synthesis enzyme (gene fas).[3]
References
External links
- Dihydropteroate+synthetase at the U.S. National Library of Medicine Medical Subject Headings (MeSH)