This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen.
The systematic name of this enzyme class is cholesterol, hydrogen-donor:oxygen oxidoreductase (25-hydroxylating).
CH25H is an interferon-stimulated gene, and its primary product 25HC may have broad-spectrum antiviral activity, demonstrated in mice against HIV, ebola, Nipah virus, Rift Valley Fever virus, and SARS-CoV-2.
Specifically, 25HC blocks membrane fusion between the cell and virus, and may "implicate membrane-modifying oxysterols as potential antiviral therapeutics.” Recently, upregulation of CH25H has been shown to play a role in effectively restricting infection of lung epithelial cells with SARS-Cov-2 through its enzymatic product, 25HC, which depletes accessible membrane cholesterol so that the virus is unable to achieve fusion with the cell membrane necessary for entry and infection.
[1] It has been proposed, based on experimental research in both mice and human cell culture, that 25HC is a potent senolytic.