Fatty acid synthase (Type I) (FASN)

Fatty acid synthase (Type I) is a large, multifunctional enzyme complex that catalyzes the de novo biosynthesis of long-chain, saturated fatty acids—primarily palmitate—using acetyl-CoA, malonyl-CoA, and NADPH as substrates[3][5][6][7]. In humans and animals, FASN is a dimeric enzyme composed of multiple catalytic domains, each responsible for steps in the fatty acid elongation cycle. The enzyme is essential for providing the lipids needed for membrane synthesis, energy storage, and cell signaling, and is tightly regulated in normal cells but often upregulated in cancer, making it a recognized therapeutic target in oncology and metabolic disease[5][6][7]. Inhibition of FASN disrupts membrane formation and energy homeostasis in cancer cells, leading to growth arrest and apoptosis[6]. FASN is distinct from the various pathways involving Coenzyme A (CoA); rather, FASN uses CoA-activated substrates (acetyl-CoA and malonyl-CoA) and does not encompass all CoA metabolic pathways, which include many unrelated enzymes and processes[3][6][7].

Other names

Fatty acid synthaseFASType I fatty acid synthaseFatty acid synthetaseFASN

Inhibition of fatty acid biosynthesis by binding to thioesterase or ketoacyl synthase domains. Irreversible or competitive inhibition of enzymatic domains essential for fatty acid elongation. Induction of apoptosis or metabolic stress in tumor cells via lipid deprivation.