Evolution
It is believed that oxidosqualene cyclases (OSCs, the class to which lanosterol cyclase belongs) evolved from bacterial squalene-hopene cyclase (SHC), which is involved with the formation of hopanoids. Phylogenetic trees constructed from the amino acid sequences of OSCs in diverse organisms suggest a single common ancestor, and that the synthesis pathway evolved only once. The discovery of steranes including cholestane in 2.7-billion year-old shales from Pilbara Craton, Australia, suggests that eukaryotes with OSCs and complex steroid machinery were present early in earth’s history.
Read more about this topic: Lanosterol Synthase
Famous quotes containing the word evolution:
“The more specific idea of evolution now reached is—a change from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity, accompanying the dissipation of motion and integration of matter.”
—Herbert Spencer (1820–1903)
“The evolution of sense is, in a sense, the evolution of nonsense.”
—Vladimir Nabokov (1899–1977)
“The evolution of humans can not only be seen as the grand total of their wars, it is also defined by the evolution of the human mind and the development of the human consciousness.”
—Friedrich Dürrenmatt (1921–1990)