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Publication Abstract from PubMed

Prodigiosin is an intensely red pigment comprising three pyrroles. The biosynthetic pathway includes a two-step proline oxidation catalyzed by PigA, using FAD as its cofactor. Here the enzyme is crystallized in apo-form and in complex with FAD and proline. As an acyl-CoA dehydrogenase (ACAD) family member, the protein folds into a beta-sheet flanked by two alpha-helical domains. PigA forms a tetramer, consistent with analytical ultracentrifugation results. FAD binds to PigA in a similar way to that in the other ACAD-family enzymes. The variable conformations of loop beta4-beta5 and helix alphaG correlate well with the structural flexibility required for substrate entrance to the Re side of FAD. Modeling with PigG, the acyl carrier protein, suggests a reasonable mode of interaction with PigA. The structure helps explain the proline oxidation mechanism, in which Glu244 plays a central role by abstracting the substrate protons. It also reveals a plausible pocket for oxygen binding to the Si side of FAD.

Crystal structure of PigA, a prolyl thioester-oxidizing enzyme in prodigiosin biosynthesis.,Lee CC, Ko TP, Chen CT, Chan YT, Lo SY, Chang JY, Chen YW, Chung TF, Hsieh HJ, Hsiao CD, Wang AH Chembiochem. 2018 Aug 10. doi: 10.1002/cbic.201800409. PMID:30095206^[3]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.