IUBMB Enzyme Nomenclature


Accepted name: carboxybiotin decarboxylase

Reaction: a carboxybiotinyl-[protein] + n Na+[side 1] + H+[side 2] = CO2 + a biotinyl-[protein] + n Na+[side 2] (n = 1-2)

For diagram of the reaction click here

Other name(s): MadB; carboxybiotin protein decarboxylase

Systematic name: carboxybiotinyl-[protein] carboxy-lyase

Comments: The integral membrane protein MadB from the anaerobic bacterium Malonomonas rubra is a component of the multienzyme complex EC, biotin-dependent malonate decarboxylase. The free energy of the decarboxylation reaction is used to pump Na+ out of the cell. The enzyme is a member of the Na+-translocating decarboxylase family, other members of which include EC [oxaloacetate decarboxylase (Na+ extruding)] and EC [(S)-methylmalonyl-CoA decarboxylase (sodium-transporting)] [2].

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


1. Berg, M., Hilbi, H. and Dimroth, P. Sequence of a gene cluster from Malonomonas rubra encoding components of the malonate decarboxylase Na+ pump and evidence for their function. Eur. J. Biochem. 245 (1997) 103-115. [PMID: 9128730]

2. Dimroth, P. and Hilbi, H. Enzymic and genetic basis for bacterial growth on malonate. Mol. Microbiol. 25 (1997) 3-10. [PMID: 11902724]

[EC created 2008 as EC, transferred 2018 to EC]

Return to EC 7.2.2 home page
Return to EC 7.2 home page
Return to EC 7 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page