• Source: Indole-3-glycerol-phosphate synthase

The enzyme 3/info/indole" target="_blank">indole-3-glycerol-phosphate synthase (IGPS) (EC 4.1.1.48) catalyzes the chemical reaction

1-(2-carboxyphenylamino)-1-deoxy-D-ribulose 5-phosphate



⇌


{\displaystyle \rightleftharpoons }

1-C-(indol-3-yl)-glycerol 3-phosphate + CO2 + H2O
This enzyme belongs to the family of lyases, to be specific, the carboxy-lyases, which cleave carbon-carbon bonds. The systematic name of this enzyme class is 1-(2-carboxyphenylamino)-1-deoxy-D-ribulose-5-phosphate carboxy-lyase [cyclizing 1-C-(indol-3-yl)glycerol-3-phosphate-forming]. Other names in common use include indoleglycerol phosphate synthetase, indoleglycerol phosphate synthase, 3/info/indole" target="_blank">indole-3-glycerophosphate synthase, 1-(2-carboxyphenylamino)-1-deoxy-D-ribulose-5-phosphate, and carboxy-lyase (cyclizing). This enzyme participates in phenylalanine, tyrosine and tryptophan biosynthesis and two-component system - general. It employs one cofactor, pyruvate.




Structural studies


In some bacteria, IGPS is a single chain enzyme. In others, such as Escherichia coli, it is the N-terminal domain of a bifunctional enzyme that also catalyses N-(5'-phosphoribosyl)anthranilate isomerase (EC 5.3.1.24) (PRAI) activity, the third step of tryptophan biosynthesis. In fungi, IGPS is the central domain of a trifunctional enzyme that contains a PRAI C-terminal domain and a glutamine amidotransferase (EC 2.4.2.-) (GATase) N-terminal domain.
A structure of the IGPS domain of the bifunctional enzyme from the mesophilic bacterium E. coli (eIGPS) has been compared with the monomeric 3/info/indole" target="_blank">indole-3-glycerol phosphate synthase from the hyperthermophilic archaeon Sulfolobus solfataricus (sIGPS). Both are single-domain (beta/alpha)8 barrel proteins, with one (eIGPS) or two (sIGPS) additional helices inserted before the first beta strand.
As of late 2007, 11 structures have been solved for this class of enzymes, with PDB accession codes 1A53, 1I4N, 1J5T, 1JCM, 1JUK, 1JUL, 1LBF, 1LBL, 1PII, 1VC4, and 2C3Z.




References






Further reading


Creighton TE, Yanofsky C (1966). "3/info/indole" target="_blank">Indole-3-glycerol phosphate synthetase of Escherichia coli, an enzyme of the tryptophan operon". J. Biol. Chem. 241 (20): 4616–24. doi:10.1016/S0021-9258(18)99693-6. PMID 5332729.
Creighton TE; Yanofsky C (1970). "Chorismate to tryptophan (Escherichia coli)—anthranilate synthetase, PR transferase, PRA isomerase, InGP synthetase, tryptophan synthetase". Chorismate to tryptophan (Escherichia coli) - Anthranilate synthetase, PR transferase, PRA isomerase, InGP synthetase, tryptophan synthetase. Methods Enzymol. Vol. 17A. pp. 365–380. doi:10.1016/0076-6879(71)17215-1. ISBN 978-0-12-181874-6.
Kung CC, Huang WN, Huang YC, Yeh KC (2006). "Proteomic survey of copper-binding proteins in Arabidopsis roots by immobilized metal affinity chromatography and mass spectrometry". Proteomics. 6 (9): 2746–58. doi:10.1002/pmic.200500108. PMID 16526091. S2CID 25896917.

Kata Kunci Pencarian:

• Indole-3-glycerol-phosphate synthase
• Indole-3-glycerol-phosphate lyase
• Trp operon
• TIM barrel
• Tryptophan synthase
• Li Jiayang
• 1-Aminocyclopropane-1-carboxylate synthase
• Tryptophan
• Camptothecin
• List of EC numbers (EC 4)