Supramolecular Assembly of an Evolved Miniprotein Host and Fluorogenic Guest Pair

Bi Xu, Xinqi Zhou, Cliff I. Stains

Research output: Contribution to journalArticlepeer-review

4 Scopus citations


Small-molecule-induced assembly of defined protein structures could have broad implications for the fabrication of new materials as well as biological signaling pathways. However, the design of new host-guest pairs capable of small-molecule-induced assembly in a biologically relevant context remains a significant challenge. Herein, we report a series of miniprotein hosts, evolved from the tenth type III domain of fibronectin (Fn3), that display remarkable binding affinity toward a red-shifted environment-sensitive merocyanine derivative, termed sI-Pht. Importantly, the consensus binder isolated from directed evolution experiments (6.2.18) forms a higher order assembly in response to addition of sI-Pht, as assessed by analytical ultracentrifugation. sI-Pht-induced assembly of 6.2.18 results in a 570-fold increase in fluorescence compared to free dye. This property enables the direct visualization of host-guest assemblies by fluorescence microscopy. As a demonstration, we show that supramolecular assembly of the 6.2.18-sI-Pht system can be visualized on the surface of living yeast cells. This new host-guest pair provides a tool for the potential development of new materials as well as pathway engineering. In a broader context, this work details a new design paradigm for the discovery of host-guest systems that function in the context of living cells.

Original languageEnglish (US)
Pages (from-to)14252-14255
Number of pages4
JournalJournal of the American Chemical Society
Issue number45
StatePublished - Nov 2 2015

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry


Dive into the research topics of 'Supramolecular Assembly of an Evolved Miniprotein Host and Fluorogenic Guest Pair'. Together they form a unique fingerprint.

Cite this