Squalene monooxygenase (also called squalene epoxidase) is a eukaryotic enzyme that uses NADPH and diatomic oxygen to oxidize squalene to 2,3-oxidosqualene (squalene epoxide). Squalene epoxidase catalyzes the first oxygenation step in sterol biosynthesis and is thought to be one of the rate-limiting enzymes in this pathway.[5] In humans, squalene epoxidase is encoded by the SQLEgene.[6]
Several eukaryote genomes lack a squalene monooxygenase encoding gene, but instead encode an alternative squalene epoxidase that performs the same task.[7]
^Nagai M, Sakakibara J, Wakui K, Fukushima Y, Igarashi S, Tsuji S, Arakawa M, Ono T (Aug 1997). "Localization of the squalene epoxidase gene (SQLE) to human chromosome region 8q24.1". Genomics. 44 (1): 141–3. doi:10.1006/geno.1997.4825. PMID9286711.