Download MendeleyMechanistic insight into allosteric activation of human pyruvate carboxylase by acetyl-CoA.
Chai, P., Lan, P., Li, S., Yao, D., Chang, C., Cao, M., Shen, Y., Ge, S., Wu, J., Lei, M., Fan, X.(2022) Mol Cell 82: 4116-4130.e6
- PubMed: 36283412
- DOI: https://doi.org/10.1016/j.molcel.2022.09.033
- Primary Citation of Related Structures:
7WTA, 7WTB, 7WTC, 7WTD, 7WTE - PubMed Abstract:
Pyruvate carboxylase (PC) catalyzes the two-step carboxylation of pyruvate to produce oxaloacetate, playing a key role in the maintenance of metabolic homeostasis in cells. Given its involvement in multiple diseases, PC has been regarded as a potential therapeutic target for obesity, diabetes, and cancer. Albeit acetyl-CoA has been recognized as the allosteric regulator of PC for over 60 years, the underlying mechanism of how acetyl-CoA induces PC activation remains enigmatic. Herein, by using time-resolved cryo-electron microscopy, we have captured the snapshots of PC transitional states during its catalytic cycle. These structures and the biochemical studies reveal that acetyl-CoA stabilizes PC in a catalytically competent conformation, which triggers a cascade of events, including ATP hydrolysis and the long-distance communication between the two reactive centers. These findings provide an integrated picture for PC catalysis and unveil the unique allosteric mechanism of acetyl-CoA in an essential biochemical reaction in all kingdoms of life.
Organizational Affiliation:
Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, People's Republic of China; Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai 200011, People's Republic of China.
