Title
Protein Handshake on the Nanoscale: How Albumin and Hemoglobin Self-Assemble into Nanohybrid Fibers
Author
Christian Helbing, Tanja Deckert-Gaudig, Izabela Firkowska-Boden, Gang Wei, Volker Deckert, Klaus D. Jandt
Year
2018
Journal
ACS Nano
Abstract
Creating and establishing proof of hybrid protein nanofibers (hPNFs), i.e., PNFs that contain more than one protein, is a currently unsolved challenge in bioinspired materials science. Such hPNFs could serve as universal building blocks for the bottom-up preparation of functional materials with bespoke properties. Here, inspired by the protein assemblies occurring in nature, we introduce hPNFs created via a facile self-assembly route and composed of human serum albumin (HSA) and human hemoglobin (HGB) proteins. Our circular dichroism results shed light on the mechanism of the proteins’ self-assembly into hybrid nanofibers, which is driven by electrostatic/hydrophobic interactions between similar amino acid sequences (protein handshake) exposed to ethanol-triggered protein denaturation. Based on nanoscale characterization with tip-enhanced Raman spectroscopy (TERS) and immunogold labeling, our results demonstrate the existence and heterogenic nature of the hPNFs and reveal the high HSA/HGB composition ratio, which is attributed to the fast self-assembling kinetics of HSA. The self-assembled hPNFs with a high aspect ratio of over 100 can potentially serve as biocompatible units to create larger bioactive structures, devices, and sensors.
Full Article
Instrument
J-715
Keywords
Circular dichroism, Secondary structure, Aggregation, Kinetics, Nanostructures, Biochemistry, Materials