Biosynthesis of a novel cyclic C35-terpene via the cyclisation of a Z-type C35-polyprenyl diphosphate obtained from a nonpathogenic Mycobacterium species

Abstract

Lipid components from 12 nonpathogenic Mycobacterium species were analysed. A novel cyclic C(35)-terpene, named heptaprenylcycline , was obtained from 3 species, while octahydroheptaprenol , which has 3 Z-double bonds, was obtained from 6 species. The amounts of and in the cultured cells increased after the 4- to 6-d stationary phase. The yield of was considerably greater at a higher temperature of 37 degrees C than at an optimal temperature of 28 degrees C, while that of remained unchanged at all temperatures. A feeding experiment with d-[1-(13)C]glucose revealed that was produced via isopentenyl diphosphate, which is a metabolite of glycolysis and the methylerythritol phosphate pathway. The conversion of octahydroheptaprenyl diphosphate to was successful by using the cell-free extracts of M. chlorophenolicum, demonstrating that is the biosynthetic intermediate of . This is the first example of the biosynthesis of a natural terpene via the cyclisation of a linear C(35)-isoprenoid. The substrate for C(35)-terpene cyclase has Z-type prenyl moieties; however, terpene cyclases usually employ E-type isoprenoids. The gene encoding the terpene cyclase that cyclises prenyl diphosphate containing Z-double bonds as the natural substrate has not yet been detected. Despite a careful search using the FASTA3 program, we could not detect any gene that is homologous to the known diphosphate-triggered type of mono-, sesqui- and diterpene cyclases in the genome of M. vanbaalenii, the DNA sequence of which has recently been elucidated. This suggests that a novel type of terpene cyclase might exist in the nonpathogenic Mycobacterium species.

Insight into C35 terpene Biosyntheses by Nonpathogenic Mycobacterium Species: Functional Analyses of Three Z‐Prenyltransferases and Identification of Dehydroheptaprenylcyclines

“…[1][2][3] We have reported that two cyclic C 35 terpenes 1 and 2 are produced only by M. vanbaalenii and M. chlorophenolicum, which degrade environmental pollutants such as polycyclic aromatic hydrocarbons and pentachlorophenol, respectively. [1,2] Our previous studies [1,2] on the biosyntheses of C 35 terpenes by Mycobacterium species have demonstrated the following points: 1) C 35 terpenes 1-4 were produced by the methylerythritol phosphate (MEP) pathway; 2) 1 was formed by a biocyclization reaction of the Z-type C 35 polyprenyl diphosphate 5; 3) the oxygenation reaction of 1 to form 2 was catalyzed by the action of P450 monooxygenase (Scheme 1).…”

Molecular profiling ofMycobacterium tuberculosisidentifies tuberculosinyl nucleoside products of the virulence-associated enzyme Rv3378c

“…This result establishes the efficacy of unbiased lipidomic screens to identify previously unknown compounds. A C35 terpene cyclase activity is found in nonpathogenic mycobacteria (31,32), but Rv3377c orthologs are only known within M. tuberculosis complex. Higher-order terpene-nucleosides are rare in nature, and we have not identified a precedent for 1-linked prenyl adenosines.…”

Unique Biosynthesis of Sesquarterpenes (C35Terpenes)

“…4, 13-18) that differ from sesquarterpenes 2-8 in B. subtilis have been found in nonpathogenic Mycobacterium species (Table 1). [32][33][34][35] Our biosynthesis study using cell-free extracts of M. chlorophenolicum indicated that a cyclic sesquarter- pene (heptaprenylcycline, 13) is biosynthesized via cyclization of a linear C 35 isoprenoid (19) (Fig. 4).…”

“…4). 32) Recently it was reported that sesquarterpenes 2-8 in B. subtilis are produced via cyclization of a linear Etype C 35 isoprenoid. [26][27][28][29] On the other hand, the cyclization of a Z-type linear isoprenoid, as observed in the formation of 13, has rarely been described.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] In contrast, little is known about C 35 terpenes. To the best of my knowledge, only 19 cyclic and eight linear C 35 terpenes have been identified to date, [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] and no family name was assigned to this terpene class until 2011. In 2011, it was proposed that these C 35 terpenes should be called sesquarterpenes as described below.…”