IUBMB Enzyme Nomenclature


Accepted name: 3-amino-5-hydroxybenzoate—[acyl-carrier protein] ligase

Reaction: ATP + 3-amino-5-hydroxybenzoate + a holo-[acyl-carrier protein] = 3-amino-5-hydroxybenzoyl-[acyl-carrier protein] + AMP + diphosphate

Other name(s): rifA (gene name); mitE (gene name)

Systematic name: 3-amino-5-hydroxybenzoate:[acyl carrier protein] ligase (AMP-forming)

Comments: During the biosynthesis of most ansamycin antibiotics such as rifamycins, streptovaricins, naphthomycins, and chaxamycins, the activity is catalysed by the loading domain of the respective polyketide synthase (PKS), which transfers the substrate to the acyl-carrier protein domain of the first extension module of the PKS. During the biosynthesis of the mitomycins the reaction is catalysed by the MitE protein, which transfers the substrate to a dedicated acyl-carrier protein (MmcB).

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


1. Admiraal, S.J., Walsh, C.T. and Khosla, C. The loading module of rifamycin synthetase is an adenylation-thiolation didomain with substrate tolerance for substituted benzoates. Biochemistry 40 (2001) 6116-6123. [PMID: 11352749]

2. Admiraal, S.J., Khosla, C. and Walsh, C.T. The loading and initial elongation modules of rifamycin synthetase collaborate to produce mixed aryl ketide products. Biochemistry 41 (2002) 5313-5324. [PMID: 11955082]

3. Admiraal, S.J., Khosla, C. and Walsh, C.T. A Switch for the transfer of substrate between nonribosomal peptide and polyketide modules of the rifamycin synthetase assembly line. J. Am. Chem. Soc. 125 (2003) 13664-13665. [PMID: 14599196]

4. Chamberland, S., Gruschow, S., Sherman, D.H. and Williams, R.M. Synthesis of potential early-stage intermediates in the biosynthesis of FR900482 and mitomycin C. Org. Lett. 11 (2009) 791-794. [PMID: 19161340]

[EC created 2021]

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