Zahra Mahmoud's Research Page

Current research.

My aim is to construct reliable building blocks for the bottom-up assembly of peptide-based biomaterials. In particular, I want to selectively modify peptides within such materials, leading to orthogonal functionalized systems, increasing their utility for applications in materials science, bionanotechnology and synthetic biologly.

My project focuses on two research areas: (1) adding function to coiled-coil Self-Assembling Fibers (SAFs); and (2) the generation of novel biomaterials by ligation.

Adding function to SAFs.

The SAF system comprises two complementary alpha-helical coiled-coil peptides peptides, SAF-p1 and SAF-p2. These assemble in aqueous solutions forming sticky ended, heterodimeric building blocks, which self-assemble to give unbranched fibers tens of microns long and 50 - 70 nm thick. X-ray diffraction and high-resolution transmission electron microscopy (TEM) show that the SAFs possess an inherent high structural order. We have been able to exploit this to design the SAF-tags, which are short, 11 mer charged peptides that bind orthogonally to the SAF fibers. In addition, we have also been able to exploit the orthogonality of the click reaction to add functionality using copper(I)-catalyzed click and thio-ene click reactions. Incorporation of these groups into the fiber allows us to tailor fiber decoration.

Self-assembly fibres

Tailoring decoration in SAFs using click chemistry.

Peptide-based BiologicallyLigated Oligopeptide Kassette (BLOK) materials.

In this concept, defined peptide subunits, based on alpha-helical coiled-coils, are assembled into long chains and alpha-helical fibrils by ligation. Ligation has little affect on the alpha-helical character of these peptides, allowing us to manipulate the specificity of the helix-helix interactions to form materials with different properties.