8SJ5

Walnut Tree Phytocystatin

Summary for 8SJ5

• Entry DOI: 10.2210/pdb8sj5/pdb
• Descriptor: Cysteine proteinase inhibitor (1 entity in total)
• Functional Keywords: cystatin, protease inhibitor, regulatory, protein binding
• Biological source: Juglans regia (English walnut)
• Total number of polymer chains: 4
• Total formula weight: 45451.18

Authors

Valadares, N.F. (deposition date: 2023-04-17, release date: 2023-12-20, Last modification date: 2023-12-27)

Primary citation

Simpson, G.A.,Rezende, I.F.,da Silva Peixoto, A.,de Oliveira Soares, I.B.,Barbosa, J.A.R.G.,de Freitas, S.M.,Valadares, N.F.
Crystal structure and interconversion of monomers and domain-swapped dimers of the walnut tree phytocystatin.
Biochim Biophys Acta Proteins Proteom, 1872:140975-140975, 2023

PubMed Abstract: Biotechnological applications of phytocystatins have garnered significant interest due to their potential applications in crop protection and improve crop resistance to abiotic stress factors. Cof1 and Wal1 are phytocystatins derived from Coffea arabica and Juglans regia, respectively. These plants hold significant economic value due to coffee's global demand and the walnut tree's production of valuable timber and widely consumed walnuts with culinary and nutritional benefits. The study involved the heterologous expression in E. coli Lemo 21(DE3), purification by immobilized metal ion affinity and size exclusion chromatography, and biophysical characterization of both phytocystatins, focusing on isolating and interconverting their monomers and dimers. The crystal structure of the domain-swapped dimer of Wal1 was determined revealing two domain-swapped dimers in the asymmetric unit, an arrangement reminiscent of the human cystatin C structure. Alphafold models of monomers and Alphafold-Multimer models of domain-swapped dimers of Cof1 and Wal1 were analyzed in the context of the crystal structure. The methodology and data presented here contribute to a deeper understanding of the oligomerization mechanisms of phytocystatins and their potential biotechnological applications in agriculture.

PubMed: 38056804
DOI: 10.1016/j.bbapap.2023.140975

Experimental method

X-RAY DIFFRACTION (3.1 Å)