Discovery and analysis of a new class of triterpenes derived from hexaprenyl pyrophosphate

Triterpenes are derived from squalene or oxidosqualene. However, a new class of triterpenes derived from hexaprenyl pyrophosphate has been recently discovered, formed by a new family of chimeric class I triterpene synthases. The cyclization mechanisms of triterpenes were elucidated by isotopic labeling and protein structural analyses, which helps understand the biosynthesis of triterpenes in nature.