Protein assembly mediated by sulfonatocalix[4]arene.

A crystal structure of lysozyme in complex with p-sulfonato-calix[4]-arene (sclx4) reveals a linear assembly of protein tetramers glued together by protein-calixarene interactions. One interaction involves encapsulation of the highly exposed C-terminal Arg128. The other involves an intricate protein-bound complex of sclx4, Mg2+ and a fragment of polyethylene glycol. [ABSTRACT FROM AUTHOR]