A single terpene synthase is responsible for a wide variety of sesquiterpenes in Sorangium cellulosum Soce56

Abstract

The myxobacterium Sorangium cellulosum So ce56 is a prolific producer of volatile sesquiterpenes. The strain harbours one of the largest prokaryotic genomes (13.1 Mbp). However, it codes only for three type I terpene synthases (TSs; sce1440, sce6369, sce8552) and one type II TS (sce4636), responsible for the production of at least 17 sesquiterpenes. We report here the gene expression of TSs and biosynthesis of the TS products in E. coli. Comparison with the So ce56 volatiles allows the assignment of the terpenes to their synthesizing genes. Both, the geosmin synthase sce1440 and the previously examined (+)-eremophilene synthase sce8552 are highly specific. In contrast, Sce6369, the first characterized 10-epi-cubebol synthase, is responsible for the formation of most of the So ce56 sesquiterpenes, mainly cadalanes and cubebanes. In contrast, Sce4636 does not convert FPP. Having characterized the So ce56 TSs, we screened all the 27 sequenced myxobacterial species from the NCBI and JGI-IMG databases for parent genes to predict the sesquiterpenes produced by them.

1H‐NMR and GC for detection of adulteration in commercial essential oils of Cymbopogon ssp

“…This is probably caused by interference of 1 H-NMR chemical shifts by other constituents within the essential oils. In order to test this hypothesis, we analysed NMR data, taken from the literature, [29][30][31][32][33][34] of the constituents present in more than 1% in the citronella oils (as analysed by GC-FID). The chemical shifts of the selected constituents are depicted in Figure S5.…”

Purification and structural analysis of volatile sesquiterpenes produced by Escherichia coli carrying unidentified terpene synthase genes from edible plants of the family Araliaceae

“…Functional identification of cryptic terpene synthase (Tps) genes have often been performed using recombinant micro-organisms containing Escherichia coli that can functionally express the corresponding Tps genes and generate the sesquiterpene synthase (TPS) products [1][2][3][4]. In many cases, the generated sesquiterpenes (the TPS products) have been analyzed by gas chromatography-mass spectrometry (GC-MS) using the MS library or co-chromatography with the authentic samples [2,3,[5][6][7][8].…”

Mechanistic investigations on six bacterial terpene cyclases

“…The closest homolog with 97% identical residues is found in S. roseum NRRL B-2638 that likely also functions as (+)-4- epi -cubebol synthase. Furthermore, a 10- epi -cubebol synthase was recently identified from Sorangium cellulosum [45], but this enzyme exhibits only poor sequence identity (29%) to the S. roseum (+)-4- epi -cubebol synthase and must have evolved independently.…”