Dimeric and tetrameric forms of enoyl-acyl carrier protein reductase from Bacillus cereus.
Enoyl-[acyl carrier protein] reductase (ENR) is an essential enzyme in type II fatty-acid synthesis that catalyzes the last step in each elongation cycle. Thus far FabI, FabL and FabK have been reported to carry out the reaction, with FabI being the most characterized. Some bacteria have more than one ENR, and Bacillus cereus has two (FabI and FabL) reported. Here, we have determined the crystal structures of the later in the apo form and in the ternary complex with NADP(+) and an indole naphthyridinone inhibitor. The two structures are almost identical, except for the three stretches that are disordered in the apo form. The apo form exists as a homo-dimer in both crystal and solution, while the ternary complex forms a homo-tetramer. The three stretches disordered in the apo structure are important in the cofactor and the inhibitor binding as well as in tetramer formation.
Kim
Su Jin
SJ
Life Sciences Division, Korea Institute of Science and Technology, 39-1 Hawolkok-dong, Sungbuk-gu, Seoul 136-791, Republic of Korea.
Ha
Byung Hak
BH
Kim
Kook-Han
KH
Hong
Seung Kon
SK
Shin
Key-Jung
KJ
Suh
Se Won
SW
Kim
Eunice Eunkyeong
EE
D000595:Amino Acid Sequence; D001051:Apoenzymes / Q000737:chemistry; D001409:Bacillus cereus / Q000201:enzymology*; D018360:Crystallography, X-Ray; D050745:Enoyl-(Acyl-Carrier Protein) Reductase (NADPH, B-Specific) / Q000037:antagonists & inhibitors / Q000737:chemistry*; D004791:Enzyme Inhibitors / Q000737:chemistry; D008969:Molecular Sequence Data; D009249:NADP / Q000737:chemistry; D055503:Protein Multimerization; D017433:Protein Structure, Secondary; D013379:Substrate Specificity
D001051:Apoenzymes; D004791:Enzyme Inhibitors; D009249:NADP; D050745:Enoyl-(Acyl-Carrier Protein) Reductase (NADPH, B-Specific)