FIG. 4.

GC-MS analysis of volatile organic compounds produced by E. coli transformants expressing single-domain sesquiterpene synthases from Nostoc. (A) E. coli cells expressing terpene synthase NS1 from Nostoc sp. produced germacrene A which undergoes a Cope rearrangement to form β-elemene under the high temperatures of the injection port. (B) E. coli cells expressing terpene synthase NP1 from N. punctiforme produced a germacrene-like compound that was structurally identified by NMR spectroscopy as 8a-epi-α-selinene.