Precisely defined protein aggregates as exemplified by crystals have applications in functional materials. Consequently, engineered protein assembly is a rapidly growing field.

Anionic calix[n]arenes are useful scaffolds that can mould to cationic protein surfaces and induce oligomerisation / assembly. Here, we describe the fabrication of different types of protein frameworks via co-crystallization with sulfonato-calix[8]arene. Calixarene-masked proteins act as nodes within the frameworks, displaying octahedral-type coordination in one case. Such supramolecular protein chemistry may benefit the development of biomaterials and therapeutics.