GO_REF:0000120

Combined Automated Annotation using Multiple IEA Methods

UniProtKB:A0A0H2MDI9

UniProtKB entry A0A0H2MDI9 (A0A0H2MDI9_VARPD): Pyrroloquinoline-quinone synthase

A0A0H2MDI9 (VPARA_00940, pqqC) is a 254-residue pyrroloquinoline-quinone synthase (EC 1.3.3.11, RHEA:10692; HAMAP MF_00654, InterPro IPR011845, NCBIfam TIGR02111) that catalyzes the ring cyclization and eight-electron oxidation of AHQQ to PQQ.

"CC -!- FUNCTION: Ring cyclization and eight-electron oxidation of 3a-(2-amino- CC 2-carboxyethyl)-4,5-dioxo-4,5,6,7,8,9-hexahydroquinoline-7,9- CC dicarboxylic-acid to PQQ. {ECO:0000256|HAMAP-Rule:MF_00654}."
Catalyzes the reaction 6-(2-amino-2-carboxyethyl)-7,8-dioxo-1,2,3,4,7,8-hexahydroquinoline-2,4-dicarboxylate + 3 O2 = pyrroloquinoline quinone + 2 H2O2 + 2 H2O + H+ (RHEA:10692, EC 1.3.3.11).

"CC -!- CATALYTIC ACTIVITY: CC Reaction=6-(2-amino-2-carboxyethyl)-7,8-dioxo-1,2,3,4,7,8- CC hexahydroquinoline-2,4-dicarboxylate + 3 O2 = pyrroloquinoline CC quinone + 2 H2O2 + 2 H2O + H(+); Xref=Rhea:RHEA:10692,"

PMID:22324760

Distribution and properties of the genes encoding the biosynthesis of the bacterial cofactor, pyrroloquinoline quinone.

Establishes PqqC as one of the five obligatory gene products (PqqA-E) for bacterial PQQ production and analyzes sequence conservation across 126 prokaryotic pqq operons.

"A total of five gene products, PqqA, PqqB, PqqC, PqqD, and PqqE, are identified as being obligatory for PQQ production."

PMID:32731194

Biogenesis of the peptide-derived redox cofactor pyrroloquinoline quinone.

Describes the catalytic mechanism of PqqC as a cofactor-less oxidase that catalyzes an eight-electron and eight-proton oxidation of AHQQ to PQQ while consuming three equivalents of O2.

"PqqC catalyzes an overall eight-electron and eight-proton oxidation on AHQQ in the absence of any organic/metal cofactor, consuming three equivalents of O2 in a single turnover manner."