O'Connor, Neil K.Neil K.O'ConnorRai, Dilip K.Dilip K.RaiClark, Benjamin R.Benjamin R.ClarkMurphy, Cormac D.Cormac D.Murphy2013-05-012013-05-012012 Elsev2012-11Journal of Fluorine Chemistryhttp://hdl.handle.net/10197/4298Incorporation of fluorine into antibiotics can moderate their biological activity, lipophilicity and metabolic stability. The introduction of fluorine into an antimicrobial lipopeptide produced by Bacillus sp. CS93 via precursor-directed biosynthesis is described. The lipopeptide surfactin is synthesised non-ribosomally by various Bacillus species and is known for its biological activity. Administering 4,4,4-trifluoro-dl-valine to cultures of Bacillus sp. CS93 results in the formation of trifluorosurfactin in quantities sufficient for detection by LC–MS/MS. 19F NMR analysis of the culture supernatant revealed that the bulk of the fluorinated amino acid was transformed and thus was unavailable for incorporation into surfactin. Detection of ammonia, and MS analysis indicated that the transformation proceeds with deamination and reduction of the keto acid, yielding 4,4,4-trifluoro-2-hydroxy-3-methylbutanoic acid.enThis is the author’s version of a work that was accepted for publication in Journal of Fluorine Chemistry. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Fluorine Chemistry (Volume 143, November 2012, Pages 210–215) DOI:10.1016/j.jfluchem.2012.06.033 Elsevier B.V.BacillusNon-ribosomal peptideFluorineBiosynthesisJournal Article14321021510.1016/j.jfluchem.2012.06.0332013-04-17https://creativecommons.org/licenses/by-nc-nd/3.0/ie/