EC Explorer

1.21.98.4

PqqA peptide cyclase

a PqqA peptide + S-adenosyl-L-methionine = a PqqA peptide with linked Glu-Tyr residues + 5′-deoxyadenosine + L-methionine

pqqE (gene name)

PqqA peptide:S-adenosyl-L-methionine oxidoreductase (cyclizing)

This bacterial enzyme, which is a member of the radical SAM protein family, catalyses the formation of a C-C bond between C-4 of glutamate and C-3 of tyrosine residues of the PqqA protein (which are separated by three amino acid residues). This is the first enzymic step in the biosynthesis of the bacterial enzyme cofactor pyrroloquinoline quinone (PQQ). The reaction is dependent on the presence of a reductant (flavodoxin) and the accessory protein PqqD.

created 2018