Diversity in steroidogenesis of symbiotic microorganisms from planthoppers

Wetzel, J.M.; Ohnishi, M.; Fujita, T.; Nakanishi, K.; Naya, Y.; Noda, H.; Sugiura, M.

Diversity in steroidogenesis of symbiotic microorganisms from planthoppers

1992

Ergosta-5,7,24(28)-trien-3 beta-ol (trienol) 6 was isolated from the intracellular symbiotes (symbiotic microorganisms) of the planthoppers, Nilaparvata lugens and Laodelphax striatellus. The steroidogenic end product of the symbiotes was found to depend on the environmental conditions, i.e., although trienol 6 was produced under symbiotic conditions, ergosterol 4 was formed in aerobic culture. When the normal diet was replaced by a steroid-deficient artificial one, the ratio of 24-methylenecholesterol 5 to total insect sterols was significantly increased. The above study offers further corroborating evidence for our assumption that the host insects require 24-methylenecholesterol 5 as an alternate source for cholesterol 1 under certain environmental conditions. In our previous biotransformation experiments, 24-methylenecholesterol 5 was shown to be an immediate precursor of cholesterol 1. However, the complexity of the insects' vital functions hindered all subsequent attempted transformations into cholesterol 1 of sitosterol 2, trienol 6, and ergosterol 4, under injection conditions.

Показать больше [+]