Qin Chuan, Graf Leonie G, Striska Kilian, Janetzky Markus, Geist Norman, Specht Robin, Schulze Sabrina, Palm Gottfried J, Girbardt Britta, Dörre Babett, Berndt Leona, Kemnitz Stefan, Doerr Mark, Bornscheuer Uwe T, Delcea Mihaela, Lammers Michael
Department of Synthetic and Structural Biochemistry, Institute of Biochemistry, University of Greifswald, 17489, Greifswald, Germany.
Department of Biophysical Chemistry, Institute of Biochemistry, University of Greifswald, 17489, Greifswald, Germany.
Nat Commun. 2024 Jul 17;15(1):6002. doi: 10.1038/s41467-024-49952-0.
The AMP-forming acetyl-CoA synthetase is regulated by lysine acetylation both in bacteria and eukaryotes. However, the underlying mechanism is poorly understood. The Bacillus subtilis acetyltransferase AcuA and the AMP-forming acetyl-CoA synthetase AcsA form an AcuA•AcsA complex, dissociating upon lysine acetylation of AcsA by AcuA. Crystal structures of AcsA from Chloroflexota bacterium in the apo form and in complex with acetyl-adenosine-5'-monophosphate (acetyl-AMP) support the flexible C-terminal domain adopting different conformations. AlphaFold2 predictions suggest binding of AcuA stabilizes AcsA in an undescribed conformation. We show the AcuA•AcsA complex dissociates upon acetyl-coenzyme A (acetyl-CoA) dependent acetylation of AcsA by AcuA. We discover an intrinsic phosphotransacetylase activity enabling AcuA•AcsA generating acetyl-CoA from acetyl-phosphate (AcP) and coenzyme A (CoA) used by AcuA to acetylate and inactivate AcsA. Here, we provide mechanistic insights into the regulation of AMP-forming acetyl-CoA synthetases by lysine acetylation and discover an intrinsic phosphotransacetylase allowing modulation of its activity based on AcP and CoA levels.
在细菌和真核生物中，形成AMP的乙酰辅酶A合成酶都受到赖氨酸乙酰化的调节。然而，其潜在机制尚不清楚。枯草芽孢杆菌乙酰转移酶AcuA与形成AMP的乙酰辅酶A合成酶AcsA形成AcuA•AcsA复合物，在AcuA对AcsA进行赖氨酸乙酰化后解离。嗜热绿弯菌AcsA的无配体形式以及与5'-单磷酸乙酰腺苷（acetyl-AMP）复合物的晶体结构表明，其灵活的C末端结构域具有不同的构象。AlphaFold2预测表明，AcuA的结合使AcsA稳定在一种未描述的构象中。我们发现，在AcuA对AcsA进行依赖于乙酰辅酶A（acetyl-CoA）的乙酰化作用后，AcuA•AcsA复合物会解离。我们发现一种内在的磷酸转乙酰酶活性，使AcuA•AcsA能够从乙酰磷酸（AcP）和辅酶A（CoA）生成乙酰辅酶A，而AcuA利用该乙酰辅酶A对AcsA进行乙酰化并使其失活。在此，我们提供了关于赖氨酸乙酰化对形成AMP的乙酰辅酶A合成酶调节的机制见解，并发现了一种内在的磷酸转乙酰酶，其可根据AcP和CoA水平调节自身活性。
