Herpetosiphon aurantiacus 114-95^T is a predatory bacterium. Its genome contains instructions for terpene cyclases, enzymes that are involved in the synthesis of terpenes. The products of several of these enzymes had not been identified so far.

Markus Nett, Technical University Dortmund, Germany, and colleagues have discovered a new natural product, herpetopanone (pictured), which is produced by Herpetosiphon aurantiacus 114-95^T. The team fed glucose, labeled with ¹³C atoms, to a culture of the bacterium, and used liquid chromatography–mass spectrometry (LC-MS) to analyze the metabolic products of the bacteria. They compared the isotope patterns of these spectra to the spectra of the metabolites produced from unlabeled glucose and were able to identify herpetopanone, a diterpene with the formula C₂₀H₃₆O₄.

The researchers repeated the fermentation on a larger scale and were able to extract 19 g of herpetopanone. The product was characterized using ¹H NMR spectroscopy. According to the team, its structure is unprecedented in bacteria.

• Herpetopanone, a diterpene from Herpetosiphon aurantiacus discovered by isotope labeling,
  Xinli Pan, Nicole Domin, Sebastian Schieferdecker, Hirokazu Kage, Martin Roth, Markus Nett,
  Beilstein J. Org. Chem. 2017, 13, 2458–2465.
  DOI: 10.3762/bjoc.13.242