posted on 2019-09-06, 14:45authored byQian Deng, Yang Liu, Linyue Chen, Meiling Xu, Nathchar Naowarojna, Norman Lee, Li Chen, Dongqing Zhu, Xuechuan Hong, Zixin Deng, Pinghua Liu, Changming Zhao
Pentalenolactone
is a microbial sesquiterpenoid with antibiotic
activity. Its biosynthetic pathway was elucidated by a combination
of genetic and biochemical characterizations of all genes involved.
For the related neopentalenoketolactone biosynthetic gene cluster
from Streptomyces avermitilis, an α-ketoglutarate-dependent
mononuclear nonheme iron enzyme, PtlD, was proposed to catalyze both
desaturation and olefin epoxidation reactions. Yet, these activities
remained to be validated by in vitro biochemical evidence. In this
report, we demonstrated that PtlD has multiple activities, including
hydroxylation, desaturation, and epoxidation, and confirmed the presence
of the elusive epoxide intermediate in a neopentalenoketolactone pathway.