8C9Y

The MK-RSL - sulfonato-calix[8]arene complex, H32 form

Summary for 8C9Y

• Entry DOI: 10.2210/pdb8c9y/pdb
• Related: 6Z5G 6Z5M 6Z5P 6Z5Q 6Z5W 6Z5X
• Descriptor: Putative fucose-binding lectin protein, sulfonato-calix[8]arene, beta-D-fructopyranose, ... (5 entities in total)
• Functional Keywords: macrocycle, calixarene, lectin, sugar binding protein
• Biological source: Ralstonia solanacearum
• Total number of polymer chains: 1
• Total formula weight: 13430.32

Authors

Mockler, N.M.,Ramberg, K.,Crowley, P.B. (deposition date: 2023-01-23, release date: 2023-07-12, Last modification date: 2024-06-19)

Primary citation

Mockler, N.M.,Ramberg, K.O.,Crowley, P.B.
Protein-macrocycle polymorphism: crystal form IV of the Ralstonia solanacearum lectin-sulfonato-calix[8]arene complex.
Acta Crystallogr D Struct Biol, 79:624-631, 2023

PubMed Abstract: Controlled protein assembly and crystallization is necessary as a means of generating diffraction-quality crystals as well as providing a basis for new types of biomaterials. Water-soluble calixarenes are useful mediators of protein crystallization. Recently, it was demonstrated that Ralstonia solanacearum lectin (RSL) co-crystallizes with anionic sulfonato-calix[8]arene (sclx) in three space groups. Two of these co-crystals only grow at pH ≤ 4 where the protein is cationic, and the crystal packing is dominated by the calixarene. This paper describes a fourth RSL-sclx co-crystal, which was discovered while working with a cation-enriched mutant. Crystal form IV grows at high ionic strength in the pH range 5-6. While possessing some features in common with the previous forms, the new structure reveals alternative calixarene binding modes. The occurrence of C-symmetric assemblies, with the calixarene at special positions, appears to be an important result for framework fabrication. Questions arise regarding crystal screening and exhaustive searching for polymorphs.

PubMed: 37314405
DOI: 10.1107/S2059798323003832

Experimental method

X-RAY DIFFRACTION (1.18 Å)