title: Crystal structures of Enoyl-ACP reductases I (FabI) and III (FabL) from B. subtilis.
abstract: Enoyl-[acyl carrier protein] (ACP) reductase (ENR) is a key enzyme in type II fatty acid synthesis that catalyzes the last step in each elongation cycle. Therefore, it has been considered as a target for antibiotics. However, recent studies indicate that some pathogens have more than one ENR; in particular, Bacillus subtilis has two ENRs, FabI and FabL. The crystal structures of the ternary complexes of BsFaBI and BsFabL are found as a homotetramer showing the same overall structure despite a sequence identity of only 24%. The positions of the catalytic dyad of Tyr-(Xaa)(6)-Lys in FabL are almost identical to that of FabI, but a detailed structural analysis shows that FabL shares more structural similarities with FabG and other members of the SDR (short-chain alcohol dehydrogenase/reductase) family. The apo FabL structure shows significantly different conformations at the cofactor and the substrate-binding regions, and this resulted in a totally different tetrameric arrangement reflecting the flexibility of these regions in the absence of the cofactor and substrate/inhibitor.
authors.affiliation: Life Sciences Division, Korea Institute of Science and Technology, 39-1 Hawolkok-dong, Sungbuk-gu, Seoul 136-791, South Korea.
authors.forename: Kook-Han
authors.initials: KH
authors.lastname: Kim
authors.forename: Byung Hak
authors.initials: BH
authors.lastname: Ha
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Kim
authors.forename: Seung Kon
authors.initials: SK
authors.lastname: Hong
authors.forename: Kwang Yeon
authors.initials: KY
authors.lastname: Hwang
authors.forename: Eunice Eunkyeong
authors.initials: EE
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology*; D001426:Bacterial Proteins / Q000737:chemistry*; D001665:Binding Sites; D002384:Catalysis; D050753:Enoyl-(Acyl-Carrier-Protein) Reductase (NADH) / Q000737:chemistry*; D008969:Molecular Sequence Data; D015394:Molecular Structure; D011485:Protein Binding; D011487:Protein Conformation; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D050753:Enoyl-(Acyl-Carrier-Protein) Reductase (NADH)