Tetrahymanol synthase

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Tetrahymanol synthase
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EC no. 4.2.1.123
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Tetrahymanol synthase (EC 4.2.1.123, squalene tetrahymanol cyclase) is an enzyme with systematic name squalene hydro-lyase (tetrahymanol forming). [1] [2] This enzyme catalyses the following chemical reaction

tetrahymanol squalene + H2O

The reaction occurs in the reverse direction.

This enzyme is isolated from Tetrahymena protozoans.

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Tetrahymanol is a gammacerane-type membrane lipid first found in the marine ciliate Tetrahymena pyriformis. It was later found in other ciliates, fungi, ferns, and bacteria. After being deposited in sediments that compress into sedimentary rocks over millions of years, tetrahymanol is dehydroxylated into gammacerane. Gammacerane has been interpreted as a proxy for ancient water column stratification.

References

  1. 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. PMID   1892870.
  2. 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. PMID   15959594.