From Proteopedia
proteopedia linkproteopedia linkProkaryotic Glutamine Synthetase Tertiary Structure: PFam domains
Prokaryotic Glutamine Synthetase is a dodecamer, comprised of 12 identical polypeptide chains, organized as a dimer of two disk like hexamers. Each protomer contains 2 Pfam domains, the Beta Grasp domain and the catalytic domain, preceded by meanders of a few resides in length which link the protomers together in the dodecamers core.
Beta Grasp domain
The beta grasp domain is the N-terminal domain, extending from residues 13-94. This domain is responsible for binding ATP, Glutamate, and Ammonia. ATP binds first, activating the site for binding glutamate.
Catalytic domain
The catalytic domain is the C-terminal domain, extending from residues 101-382.
Active site
The dodecamer contains 12 active sites total, each formed from the Beta grasp domain of one protomer and the Catalytic domain of the neighboring protomer.
