This enzyme is isolated from Tetrahymena protozoans.
References
^Saar J, Kader JC, Poralla K, Ourisson G (September 1991). "Purification and some properties of the squalene-tetrahymanol cyclase from Tetrahymena thermophila". Biochimica et Biophysica Acta (BBA) - General Subjects. 1075 (1): 93–101. doi:10.1016/0304-4165(91)90080-z. PMID1892870.
^Giner JL, Rocchetti S, Neunlist S, Rohmer M, Arigoni D (June 2005). "Detection of 1,2-hydride shifts in the formation of euph-7-ene by the squalene-tetrahymanol cyclase of Tetrahymena pyriformis". Chemical Communications (24): 3089–91. doi:10.1039/b504300j. PMID15959594.