1jbv
From Proteopedia
|
FPGS-AMPPCP complex
Overview
Folic acid is an essential vitamin for normal cell growth, primarily, through its central role in one-carbon metabolism. Folate analogs, (antifolates) are targeted at the same reactions and are widely used as, therapeutic drugs for cancer and bacterial infections. Effective retention, of folates in cells and the efficacy of antifolate drugs both depend upon, the addition of a polyglutamate tail to the folate or antifolate molecule, by the enzyme folylpolyglutamate synthetase (FPGS). The reaction mechanism, involves the ATP-dependent activation of the free carboxylate group on the, folate molecule to give an acyl phosphate intermediate, followed by attack, by the incoming L-glutamate substrate. FPGS shares a number of structural, and mechanistic details with the bacterial cell wall ligases MurD, MurE, and MurF, and these enzymes, along with FPGS, form a subfamily of the, ADP-forming amide bond ligase family. High-resolution crystallographic, analyses of binary and ternary complexes of Lactobacillus casei FPGS, reveal that binding of the first substrate (ATP) is not sufficient to, generate an active enzyme. However, binding of folate as the second, substrate triggers a large conformational change that activates FPGS and, allows the enzyme to adopt a form that is then able to bind the third, substrate, L-glutamate, and effect the addition of a polyglutamate tail to, the folate.
About this Structure
1JBV is a Single protein structure of sequence from Lactobacillus casei with MG and ACP as ligands. Active as Tetrahydrofolate synthase, with EC number 6.3.2.17 Full crystallographic information is available from OCA.
Reference
Folate-binding triggers the activation of folylpolyglutamate synthetase., Sun X, Cross JA, Bognar AL, Baker EN, Smith CA, J Mol Biol. 2001 Jul 27;310(5):1067-78. PMID:11501996
Page seeded by OCA on Tue Nov 20 18:05:34 2007
