Conserved Site

3-phosphoshikimate 1-carboxyvinyltransferase, conserved site (IPR023193)

Short name: EPSP_synthase_CS


This entry represents 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase (also known as 3-phosphoshikimate 1-carboxyvinyltransferase), catalyses the sixth step in the biosynthesis from chorismate of the aromatic amino acids (the shikimate pathway) in bacteria (gene aroA), plants and fungi (where it is part of a multifunctional enzyme which catalyses five consecutive steps in this pathway) [PMID: 11607190]. The sixth step is the formation of EPSP and inorganic phosphate from shikimate-3-phosphate (S3P) and phosphoenolpyruvate (PEP).

EPSP can use shikimate or shikimate-3-phosphate as a substrate. By binding shikimate, the backbone of the active site is changed, which affects the binding of glyphosate and renders the reaction insensitive to inhibition by glyphosate [PMID: 16225867]. On isolation of the discontinuous C-terminal domain, it was found that it binds neither its substrate nor its inhibitor but maintains structural integrity [PMID: 18051609].

Earlier studies suggested that the active site of the enzyme is in the cleft between its two globular domains. When the enzyme binds S3P, there is a conformational change in the isolated N-terminal domain [PMID: 11300775]. The sequence of EPSP from various biological sources shows that the structure of the enzyme has been well conserved throughout evolution and since the shikimate pathway is not present in vertebrates but is essential for the life of plants, fungi and bacteria; it is commonly viewed as a target for weed killers and antimicrobial drug development.

This entry represents two conserved regions as signature patterns. The first pattern corresponds to a region that is part of the active site and which is also important for the resistance to glyphosate [PMID: 1939260]. The second pattern is located in the C-terminal part of the protein and contains a conserved lysine which seems to be important for the activity of the enzyme.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
PROSITE patterns
PROSITE patterns