IUBMB Enzyme Nomenclature


Accepted name: aminodeoxychorismate synthase

Reaction: chorismate + L-glutamine = 4-amino-4-deoxychorismate + L-glutamate

For diagram click here.

Other name(s): ADC synthase; 4-amino-4-deoxychorismate synthase; PabB; chorismate:L-glutamine amido-ligase (incorrect)

Systematic name: chorismate:L-glutamine aminotransferase

Comments: The enzyme is composed of two parts, PabA and PabB. In the absence of PabA and glutamine, PabB converts ammonia and chorismate into 4-amino-4-deoxychorismate (in the presence of Mg2+). PabA converts glutamine into glutamate only in the presence of stoichiometric amounts of PabB. This enzyme is coupled with, aminodeoxychorismate lyase, to form 4-aminobenzoate.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number:


1. Ye, Q.Z., Liu, J. and Walsh, C.T. p-Aminobenzoate synthesis in Escherichia coli: purification and characterization of PabB as aminodeoxychorismate synthase and enzyme X as aminodeoxychorismate lyase. Proc. Natl. Acad. Sci. USA 87 (1990) 9391-9395. [PMID: 2251281]

2. Viswanathan, V.K., Green, J.M. and Nichols, B.P. Kinetic characterization of 4-amino 4-deoxychorismate synthase from Escherichia coli. J. Bacteriol. 177 (1995) 5918-5923. [PMID: 7592344]

[EC created 2003 as EC, transferred 2007 to EC]

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