Fig. 2
From: Metabolic engineering strategies for de novo biosynthesis of sterols and steroids in yeast
Regulation mechanisms and the corresponding metabolic engineering strategies for regulating de novo biosynthesis of sterols and steroids in yeast. A Mechanism and strategies for regulation of the ergosterol synthesis pathway; B Mechanism and strategies for regulation of sterol homeostasis. Enzymes: CoA coenzyme A; Erg10p acetoacetyl-CoA thiolase; Erg13p hydroxymethylglutaryl-coenzyme A synthase; Hmg1/2p hydroxymethylglutaryl-coenzyme A reductase; Erg12p mevalonate kinase; Erg8p phosphomevalonate kinase; Erg19p diphosphomevalonate decarboxylase; Idi1p isopentenyl diphosphate isomerase; Erg20p polyprenyl synthetase; Erg9p squalene synthetase; Erg1p squalene epoxidase; Erg7p lanosterol cyclase/lanosterol synthase; Erg11p cytochrome P450 lanosterol 14α-demethylase; Erg24p sterol C-14 reductase; Erg25p C-4 methyl sterol oxidase; Erg26p sterol C-4 decarboxylases; Erg27p 3-keto-steroid reductase; Erg6p C-24 sterol methyltransferase; Erg2p C-8 sterol isomerase; Erg3p C-5 sterol desaturase; Erg5p C-22 sterol desaturase; Erg4p C24 (28) sterol reductase; Adh2p alcohol dehydrogenase; Ald6p aldehyde dehydrogenase; Acsp acetyl-CoA synthetase; Aclp ATP-citrate lyase; Acc1p/Hfa1p acetyl-CoA carboxylase; Pox1-6p peroxisome acyl-CoA oxidase 1–6; AOX1p alternative oxidase; NOXp NADH oxidase; Are1/2p acyl-CoA sterol acyltransferase; Tgl1p steryl ester hydrolase; Yeh1/2p yeast steryl ester hydrolase; Atf2p acetyltransferase; Say1p steryl acetyl hydrolase; Tgl3/4/5p triacylglycerol lipase; Dga1p diacylglycerol acyltransferase; Pah1p phosphatidic acid phosphohydrolase; Lro1p triacylglycerol synthase; Fld1p seipin involved in LD assembly; Pex30p peroxisome related protein; Pet10p perilipin involved in formation and stability of LDs; Aus1p ABC protein involved in uptake of sterols; Pdr11p pleiotropic drug resistance protein 11. Substrates: HMG-CoA 3-hydroxy-3-methylglutaryl-CoA; P phosphate; PA phosphatidic acid; DAG diacylglycerol; TAG triacylglycerol; SE steryl ester; FFA free fatty acids; CDP-DAG cytidine diphosphate-diacylglycerol; PI phosphatidylinositol; PS phosphatidylserine; PE phosphatidylethanolamine; PC phosphatidylcholine