20.500.12556/RUL-129498 Steroidal triterpenes of cholesterol synthesis Cholesterol synthesis is a ubiquitous and housekeeping metabolic pathway that leads to cholesterol, an essential structural component of mammalian cell membranes, required for proper membrane permeability and fluidity. The last part of the pathway involves steroidal triterpenes with cholestane ring structures. It starts by conversion of acyclic squalene into lanosterol, the first sterol intermediate of the pathway, followed by production of 20 structurally very similar steroidal triterpene molecules in over 11 complex enzyme reactions. Due to the structural similarities of sterol intermediates and the broad substrate specificity of the enzymes involved (especially sterol-Δ$^{24}$-reductase; DHCR24) the exact sequence of the reactions between lanosterol and cholesterol remains undefined. This article reviews all hitherto known structures of post-squalene steroidal triterpenes of cholesterol synthesis, their biological roles and the enzymes responsible for their synthesis. Furthermore, it summarises kinetic parameters of enzymes (V$_{max}$ and K$_m$) and sterol intermediate concentrations from various tissues. Due to the complexity of the post-squalene cholesterol synthesis pathway, future studies will require a comprehensive meta-analysis of the pathway to elucidate the exact reaction sequence in different tissues, physiological or disease conditions. A major reason for the standstill of detailed late cholesterol synthesis research was the lack of several steroidal triterpene standards. We aid to this efforts by summarizing commercial and laboratory standards, referring also to chemical syntheses of meiosis-activating sterols. sterols steroidal triterpenes cholesterol synthesis post-squalene pathway steroli steroidni triterpeni sinteza holesterola true false true Angleški jezik Slovenski jezik Članek v reviji 2021-09-02 09:32:33 2021-09-02 09:32:35 2022-09-08 04:08:53 0000-00-00 00:00:00 2013 0 0 Str. 4002-4017 iss. 4 Vol. 18 2013 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 577 1420-3049 10.3390/molecules18044002 30538457 RAZ_Acimovic_Jure_2013.pdf RAZ_Acimovic_Jure_2013.pdf 1 8230163F32F2E1450EC2B9C17C821F5B 8f609c19b01c769ed510e9de03258372e8b1304d68d236c7ca8a741992140cf3 f32feeb4-0bbf-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=146478 http://www.mdpi.com/1420-3049/18/4/4002 1 b5d31832-0bbf-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=146477 Medicinska fakulteta 0 0 0