Structural highlights
Function
[FAS2_YEAST] Fatty acid synthetase catalyzes the formation of long-chain fatty acids from acetyl-CoA, malonyl-CoA and NADPH. The alpha subunit contains domains for: acyl carrier protein, 3-oxoacyl-[acyl-carrier-protein] reductase, and 3-oxoacyl-[acyl-carrier-protein] synthase. This subunit coordinates the binding of the six beta subunits to the enzyme complex.[HAMAP-Rule:MF_00101] [TMA17_YEAST] ATPase-dedicated chaperone that assists the formation of the RPT6-RPT3 ATPase pair, an early step in proteasome assembly. Plays a key role in maintaining homeostatic proteasome levels and adjusting proteasome assembly when demands increase, such as during proteasome stresses. Function overlaps with RPN14.[1] [FAS1_YEAST] Fatty acid synthetase catalyzes the formation of long-chain fatty acids from acetyl-CoA, malonyl-CoA and NADPH. The beta subunit contains domains for: [acyl-carrier-protein] acetyltransferase and malonyltransferase, S-acyl fatty acid synthase thioesterase, enoyl-[acyl-carrier-protein] reductase, and 3-hydroxypalmitoyl-[acyl-carrier-protein] dehydratase.
Publication Abstract from PubMed
Fatty acid synthases (FASs) are central to metabolism but are also of biotechnological interest for the production of fine chemicals and biofuels from renewable resources. During fatty acid synthesis, the growing fatty acid chain is thought to be shuttled by the dynamic acyl carrier protein domain to several enzyme active sites. Here, we report the discovery of a gamma subunit of the 2.6 megadalton alpha6-beta6S. cerevisiae FAS, which is shown by high-resolution structures to stabilize a rotated FAS conformation and rearrange ACP domains from equatorial to axial positions. The gamma subunit spans the length of the FAS inner cavity, impeding reductase activities of FAS, regulating NADPH turnover by kinetic hysteresis at the ketoreductase, and suppressing off-pathway reactions at the enoylreductase. The gamma subunit delineates the functional compartment within FAS. As a scaffold, it may be exploited to incorporate natural and designed enzymatic activities that are not present in natural FAS.
Discovery of a Regulatory Subunit of the Yeast Fatty Acid Synthase.,Singh K, Graf B, Linden A, Sautner V, Urlaub H, Tittmann K, Stark H, Chari A Cell. 2020 Mar 4. pii: S0092-8674(20)30211-7. doi: 10.1016/j.cell.2020.02.034. PMID:32160528[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Hanssum A, Zhong Z, Rousseau A, Krzyzosiak A, Sigurdardottir A, Bertolotti A. An inducible chaperone adapts proteasome assembly to stress. Mol Cell. 2014 Aug 21;55(4):566-77. doi: 10.1016/j.molcel.2014.06.017. Epub 2014 , Jul 17. PMID:25042801 doi:http://dx.doi.org/10.1016/j.molcel.2014.06.017
- ↑ Singh K, Graf B, Linden A, Sautner V, Urlaub H, Tittmann K, Stark H, Chari A. Discovery of a Regulatory Subunit of the Yeast Fatty Acid Synthase. Cell. 2020 Mar 4. pii: S0092-8674(20)30211-7. doi: 10.1016/j.cell.2020.02.034. PMID:32160528 doi:http://dx.doi.org/10.1016/j.cell.2020.02.034
