IntEnz

EC 4.1.3.27 - Anthranilate synthase

IntEnz Enzyme Nomenclature
EC 4.1.3.27

Names

Reactions

• (1) chorismate + L-glutamine = anthranilate + pyruvate + L-glutamate
•   (1a) L-glutamine + H2O = L-glutamate + NH3
•   (1b) chorismate + NH3 = (2S)-2-amino-4-deoxychorismate + H2O
•   (1c) (2S)-2-amino-4-deoxychorismate = anthranilate + pyruvate

Comments:

The enzyme, found in plants, fungi and bacteria is composed of two parts, a glutaminase subunit and a lyase subunit. The glutaminase produces ammonia that is channeled to the lyase subunit. In the absence of the glutaminase, the lyase can convert ammonia and chorismate into anthranilate. In some organisms, this enzyme is part of a multifunctional protein, together with one or more other components of the system for the biosynthesis of tryptophan [EC 2.4.2.18 (anthranilate phosphoribosyltransferase), EC 4.1.1.48 (indole-3-glycerol-phosphate synthase), EC 4.2.1.20 (tryptophan synthase) and EC 5.3.1.24 (phosphoribosylanthranilate isomerase)].

Links to other databases

References

1. Baker, T. and Crawford, I.P.
   Anthranilate synthetase. Partial purification and some kinetic studies on the enzyme from Escherichia coli.
   J. Biol. Chem. 241 : 5577-5584 (1966). [PMID: 5333199]
2. Creighton, T.E. and Yanofsky, C.
   Chorismate to tryptophan (Escherichia coli) - anthranilate synthetase, PR transferase, PRA isomerase, InGP synthetase, tryptophan synthetase.
   Methods Enzymol. 17A : 365-380 (1970).
3. Hütter, R., Niederberger, P. and DeMoss, J.A.
   Tryptophan biosynthetic genes in eukaryotic microorganisms.
   Annu. Rev. Microbiol. 40 : 55-77 (1986).
4. Ito, J. and Yanofsky, C.
   Anthranilate synthetase, an enzyme specified by the tryptophan operon of Escherichia coli: Comparative studies on the complex and the subunits.
   J. Bacteriol. 97 : 734-742 (1969). [PMID: 4886290]
5. Zalkin, H. and Kling, D.
   Anthranilate synthetase. Purification and properties of component I from Salmonella typhimurium.
   Biochemistry 7 : 3566-3573 (1968). [PMID: 4878701]
6. Morollo, A. A., Bauerle, R.
   Characterization of composite aminodeoxyisochorismate synthase and aminodeoxyisochorismate lyase activities of anthranilate synthase.
   Proc Natl Acad Sci U S A 90 : 9983-9987 (1993). [PMID: 8234345]
7. Kanno, T., Kasai, K., Ikejiri-Kanno, Y., Wakasa, K., Tozawa, Y.
   In vitro reconstitution of rice anthranilate synthase: distinct functional properties of the alpha subunits OASA1 and OASA2.
   Plant Mol Biol 54 : 11-22 (2004). [PMID: 15159631]

[EC 4.1.3.27 created 1972]