4V2P:
reference: In vitro reconstitution of alpha-pyrone ring formation in myxopyronin biosynthesis., Sucipto H, Sahner JH, Prusov E, Wenzel SC, Hartmann RW, Koehnke J, Muller R, Chem Sci. 2015 Aug 1;6(8):5076-5085. doi: 10.1039/c5sc01013f. Epub 2015 May 18. PMID: 29308173

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