approach. The genes responsible for the production of 1, 154, and 155 are from the
fungi Penicillium brasilianum NBRC 6234, Phoma betae PS-13, and Bipolaris
maydis ATCC48331, respectively. Of these, 108 and 109 with 5/12/5-membered
ring systems were isolated from Nature, as mentioned in Sect. 6.1.2. However, the
configurations and positions of the double bonds of 1, 154, 155, 108, and 109 are
different from each other.
10.8 Genes for the Formation of a Linear Sesterterpenoid
Genes for the biosynthesis of linear sesterterpenoids have also been found. For
example, a gene from the bacterium Bacillus clausii encodes an enzyme that can
transform geranylfarnesyl diphosphate (8) into a linear sesterterpene, hydrocarbon
β-geranylfarnesene (156) (Fig. 110) [139].
10.9 Genes Encoding a Membrane-Bound Sesterterpene
Cyclase
The typical terpene cyclases, which catalyze type 1 terpene cyclization reactions, are
soluble proteins. However, there are also membrane-bound terpene cyclases for
type 1 cyclization reactions, and they are referred to as UbiA-type terpene cyclases.
A gene encoding a UbiA-type terpene cyclase involved in the biosynthesis of
sesterterpenoids has been found in the bacterium Streptomyces somaliensis
[140]. This enzyme can convert geranylfarnesyl diphosphate (8) to somaliensenes
A (157) and B (158) (Fig. 111).
OPP
H
8
156
Fig. 110 Structure and formation of β-geranylfarnesene (156)
Sesterterpenoids
63
fungi Penicillium brasilianum NBRC 6234, Phoma betae PS-13, and Bipolaris
maydis ATCC48331, respectively. Of these, 108 and 109 with 5/12/5-membered
ring systems were isolated from Nature, as mentioned in Sect. 6.1.2. However, the
configurations and positions of the double bonds of 1, 154, 155, 108, and 109 are
different from each other.
10.8 Genes for the Formation of a Linear Sesterterpenoid
Genes for the biosynthesis of linear sesterterpenoids have also been found. For
example, a gene from the bacterium Bacillus clausii encodes an enzyme that can
transform geranylfarnesyl diphosphate (8) into a linear sesterterpene, hydrocarbon
β-geranylfarnesene (156) (Fig. 110) [139].
10.9 Genes Encoding a Membrane-Bound Sesterterpene
Cyclase
The typical terpene cyclases, which catalyze type 1 terpene cyclization reactions, are
soluble proteins. However, there are also membrane-bound terpene cyclases for
type 1 cyclization reactions, and they are referred to as UbiA-type terpene cyclases.
A gene encoding a UbiA-type terpene cyclase involved in the biosynthesis of
sesterterpenoids has been found in the bacterium Streptomyces somaliensis
[140]. This enzyme can convert geranylfarnesyl diphosphate (8) to somaliensenes
A (157) and B (158) (Fig. 111).
OPP
H
8
156
Fig. 110 Structure and formation of β-geranylfarnesene (156)
Sesterterpenoids
63