7WAE

Trichodesmium erythraeum cyanophycin synthetase 1 (TeCphA1) with ATPgammaS, 4x(beta-Asp-Arg), and aspartate

Summary for 7WAE

• Entry DOI: 10.2210/pdb7wae/pdb
• EMDB information: 32383
• Descriptor: Cyanophycin synthase, 4x(beta-Asp-Arg), MAGNESIUM ION, ... (6 entities in total)
• Functional Keywords: cyanophycin, non-ribosomal peptide synthesis, atp, aspartate, arginine, ligase
• Biological source: Trichodesmium erythraeum IMS101; More
• Total number of polymer chains: 8
• Total formula weight: 404221.23

Authors

Miyakawa, T.,Yang, J.,Kawasaki, M.,Adachi, N.,Fujii, A.,Miyauchi, Y.,Muramatsu, T.,Moriya, T.,Senda, T.,Tanokura, M. (deposition date: 2021-12-14, release date: 2022-09-07, Last modification date: 2024-11-20)

Primary citation

Miyakawa, T.,Yang, J.,Kawasaki, M.,Adachi, N.,Fujii, A.,Miyauchi, Y.,Muramatsu, T.,Moriya, T.,Senda, T.,Tanokura, M.
Structural bases for aspartate recognition and polymerization efficiency of cyanobacterial cyanophycin synthetase.
Nat Commun, 13:5097-5097, 2022

PubMed Abstract: Cyanophycin is a natural biopolymer consisting of equimolar amounts of aspartate and arginine as the backbone and branched sidechain, respectively. It is produced by a single enzyme, cyanophycin synthetase (CphA1), and accumulates as a nitrogen reservoir during N fixation by most cyanobacteria. A recent structural study showed that three constituent domains of CphA1 function as two distinct catalytic sites and an oligomerization interface in cyanophycin synthesis. However, it remains unclear how the ATP-dependent addition of aspartate to cyanophycin is initiated at the catalytic site of the glutathione synthetase-like domain. Here, we report the cryogenic electron microscopy structures of CphA1, including a complex with aspartate, cyanophycin primer peptide, and ATP analog. These structures reveal the aspartate binding mode and phosphate-binding loop movement to the active site required for the reaction. Furthermore, structural and mutational data show a potential role of protein dynamics in the catalytic efficiency of the arginine condensation reaction.

PubMed: 36042318
DOI: 10.1038/s41467-022-32834-8

Experimental method

ELECTRON MICROSCOPY (2.64 Å)