Chemically Programmed Supramolecular Assembly of Hemoprotein and Streptavidin with Alternating Alignment

It is shown that an intramolecularly linked cofactor dyad enforces the assocn. of two different proteins according to a predefined program.  The present study demonstrates that the heme-bis(biotin) conjugate contains the information to produce a stable 2:1 Mb-SAv complex.  Propagation of this moiety into a polymer results from using a dimericMb building block.  The supramol. composite fiber obsd. by AFM techniques is the first example of a chem. programmed heterotropic protein copolymer with alternating alignment.  The heme cofactor's dioxygen binding function is maintained upon incorporation within the fiber, suggesting that this approach is well-suited for the creation of functional nanobiomaterials.  Immobilization of the first building block will allow to: (1) study the programmed assembly by quartz microbalance anal., (2) increase the complexity by varying the capping groups on the dyad and/or (3) introduce addnl. protein building blocks to afford protein polymers with a desired sequence and function.  Potential applications include multifunctional catalysis, artificial photosynthesis, and smart nanomaterials for medical applications.