7V4K

Cryo-EM Structure of Camellia sinensis glutamine synthetase CsGSIb inactive Pentamer State II

Summary for 7V4K

• Entry DOI: 10.2210/pdb7v4k/pdb
• EMDB information: 31714
• Descriptor: Glutamine synthetase (1 entity in total)
• Functional Keywords: supramolecular enzyme, glutamine synthetase, camellia sinensis, plant protein, immune system
• Biological source: Camellia sinensis (Tea)
• Total number of polymer chains: 5
• Total formula weight: 196445.90

Authors

Xu, W.,Chen, Y.,Xing, Q.,Huang, C. (deposition date: 2021-08-13, release date: 2022-05-18, Last modification date: 2024-06-12)

Primary citation

Chen, Y.,Xu, W.,Yu, S.,Ni, K.,She, G.,Ye, X.,Xing, Q.,Zhao, J.,Huang, C.
Assembly status transition offers an avenue for activity modulation of a supramolecular enzyme.
Elife, 10:-, 2021

PubMed Abstract: Nature has evolved many supramolecular proteins assembled in certain, sometimes even seemingly oversophisticated, morphological manners. The rationale behind such evolutionary efforts is often poorly understood. Here, we provide atomic-resolution insights into how the dynamic building of a structurally complex enzyme with higher order symmetry offers amenability to intricate regulation. We have established the functional coupling between enzymatic activity and protein morphological states of glutamine synthetase (GS), an old multi-subunit enzyme essential for cellular nitrogen metabolism. Cryo-EM structure determination of GS in both the catalytically active and inactive assembly states allows us to reveal an unanticipated self-assembly-induced disorder-order transition paradigm, in which the remote interactions between two subcomplex entities significantly rigidify the otherwise structurally fluctuating active sites, thereby regulating activity. We further show in vivo evidences that how the enzyme morphology transitions could be modulated by cellular factors on demand. Collectively, our data present an example of how assembly status transition offers an avenue for activity modulation, and sharpens our mechanistic understanding of the complex functional and regulatory properties of supramolecular enzymes.

PubMed: 34898426
DOI: 10.7554/eLife.72535

Experimental method

ELECTRON MICROSCOPY