Das Institut für Biochemie lädt gemeinsam mit dem Ortsverband der Gesellschaft Deutscher Chemiker zu einem
K o l l o q u i u m der GDCh
Großer Hörsaal des Instituts für Biochemie
Felix-Hausdorff-Str. 4, Greifswald
Montag, 20. April 2026, 16 Uhr c.t.
Dr. Liujuan Zheng
Philipps Universität Marburg, MPI for Terrestrial Microbiology/Marburg
spricht zum Thema:
Acetate Switch: From Polyketide Biosynthesis to Protein Acetylation Regulation
Abstract:
The metabolic “acetate switch” connects central carbon metabolism with both natural product biosynthesis and post-translational regulation. I will first show how the acetate switch can be applied to decode the biosynthesis of polyketides in bacteria and filamentous fungi.
More importantly, I will present how the acetate switch is regulated in Bacillus subtilis. Acetyl-CoA synthetase (AcsA), a key enzyme in acetate metabolism, is controlled by reversible lysine acetylation through the acuABC operon. We identified a pausing complex between the acetyltransferase AcuA and AcsA in the absence of acetyl-CoA. Cryo-EM analysis reveals that AcuA traps the catalytic lysine of AcsA and blocks its CoA-binding pocket, thereby preventing catalysis, while physiological levels of acetyl-CoA trigger dissociation of this complex and promote acetylation. In parallel, the regulatory protein AcuB binds the alarmone Ap4A with nanomolar affinity and inhibits the deacetylase AcuC through complex formation, a process further strengthened by Ap4A. Together, these results uncover a multilayer regulatory network linking metabolic state and stress signaling to protein acetylation control, providing new mechanistic insights into the interplay between metabolism and enzyme regulation.
Einladende
Prof. Dr. Michael Lammers
Dr. Christian Fischer; Vorsitzender des Ortsverbandes der GDCh