Reaction: ATP + 3'-dephospho-CoA = 2'-(5-triphospho-α-D-ribosyl)-3'-dephospho-CoA + adenine
For diagram of reaction click here.
Other name(s): 2'-(5''-triphosphoribosyl)-3-dephospho-CoA synthase; ATP:dephospho-CoA 5-triphosphoribosyl transferase; CitG; ATP:dephospho-CoA 5'-triphosphoribosyl transferase; MdcB; ATP:3-dephospho-CoA 5''-triphosphoribosyltransferase; MadG
Systematic name: ATP:3'-dephospho-CoA 5-triphosphoribosyltransferase
Comments: ATP cannot be replaced by GTP, CTP, UTP, ADP or AMP. The reaction involves the formation of a new α (1''→2') glycosidic bond between the two ribosyl moieties, with concomitant displacement of the adenine moiety of ATP [1,4]. The 2'-(5-triphosphoribosyl)-3'-dephospho-CoA produced can be transferred by EC 2.7.7.61, citrate lyase holo-[acyl-carrier protein] synthase, to the apo-acyl-carrier protein subunit (γ-subunit) of EC 4.1.3.6, citrate (pro-3S) lyase, thus converting it from an apo-enzyme into a holo-enzyme [1,3]. Alternatively, it can be transferred to the apo-ACP subunit of malonate decarboxylase by the action of EC 2.7.7.66, malonate decarboxylase holo-[acyl-carrier protein] synthase [4].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 313345-38-9
References:
1. Schneider, K., Dimroth, P. and Bott, M. Biosynthesis of the prosthetic group of citrate lyase. Biochemistry 39 (2000) 9438-9450. [PMID: 10924139]
2. Schneider, K., Dimroth, P. and Bott, M. Identification of triphosphoribosyl-dephospho-CoA as precursor of the citrate lyase prosthetic group. FEBS Lett. 483 (2000) 165-168. [PMID: 11042274]
3. Schneider, K., Kästner, C.N., Meyer, M., Wessel, M., Dimroth, P. and Bott, M. Identification of a gene cluster in Klebsiella pneumoniae which includes citX, a gene required for biosynthesis of the citrate lyase prosthetic group. J. Bacteriol. 184 (2002) 2439-2446. [PMID: 11948157]
4. Hoenke, S., Wild, M.R. and Dimroth, P. Biosynthesis of triphosphoribosyl-dephospho-coenzyme A, the precursor of the prosthetic group of malonate decarboxylase. Biochemistry 39 (2000) 13223-13232. [PMID: 11052675]