Details

Autor(en) / Beteiligte

• Zhou, Jiashen
• Zhang, Lin
• Wang, Yiran
• Song, Wenyan
• Huang, Yuzhou
• Mu, Yajuan
• Schmitz, Werner
• Zhang, Shu‐Yu
• Lin, Houwen
• Chen, Hong‐Zhuan
• Ye, Fei
• Zhang, Liang

Titel

The Molecular Basis of Catalysis by SDR Family Members Ketoacyl‐ACP Reductase FabG and Enoyl‐ACP Reductase FabI in Type‐II Fatty Acid Biosynthesis

Ist Teil von

• Angewandte Chemie (International ed.), 2023-11, Vol.62 (46), p.e202313109-n/a

Auflage

International ed. in English

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2023

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The short‐chain dehydrogenase/reductase (SDR) superfamily members acyl‐ACP reductases FabG and FabI are indispensable core enzymatic modules and catalytic orientation controllers in type‐II fatty acid biosynthesis. Herein, we report their distinct substrate allosteric recognition and enantioselective reduction mechanisms. FabG achieves allosteric regulation of ACP and NADPH through ACP binding across two adjacent FabG monomers, while FabI follows an irreversible compulsory order of substrate binding in that NADH binding must precede that of ACP on a discrete FabI monomer. Moreover, FabG and FabI utilize a backdoor residue Phe187 or a “rheostat” α8 helix for acyl chain length selection, and their corresponding triad residues Ser142 or Tyr145 recognize the keto‐ or enoyl‐acyl substrates, respectively, facilitating initiation of nucleophilic attack by NAD(P)H. The other two triad residues (Tyr and Lys) mediate subsequent proton transfer and (R)‐3‐hydroxyacyl‐ or saturated acyl‐ACP production. The distinct substrate allosteric recognition and reduction catalytic mechanisms of ketoacyl‐ACP reductase FabG and enoyl‐ACP reductase FabI in Type‐II fatty acid biosynthesis are reported. The enzymes use alternative catalytic tunnels and core catalytic triads to recognize different ACP, NAD(P)H and fatty acid substrates for asymmetric reduction catalysis.