Investigation of self-assembling proline- and glycine-rich recombinant proteins and peptides inspired by proteins from a symbiotic fungus using atomic force microscopy and circular dichroism spectroscopy

摘要: Fiber-forming proteins and peptides are being scrutinized as a promising source of building blocks for new nanomaterials. Arabinogalactan-like (AGL) expressed at the symbiotic interface between plant roots arbuscular mycorrhizal fungi have novel sequences, hypothesized to form polyproline II (PPII) helix structures. The functional nature these is unknown but they may structures establishment maintenance fungal hyphae. Here we show that recombinant AGL1 (rAGL1) AGL3 (rAGL3) extended based upon secondary structural characteristics determined by electronic circular dichroism (CD) spectroscopy can self-assemble into fibers microtubes observed atomic force microscopy (AFM) scanning electron (SEM). CD results synthetic on repeat regions in AGL1, AGL2 suggest contain significant amounts PPII helices influenced ionic strength and, least one case, concentration. Point mutations single residue region resulted altered Self-assembly repeats was means AFM optical microscopy. Peptide (APADGK)6 forms with similar morphology rAGL1 suggesting crucial fibers. These self-assembling sequences find applications precursors bioinspired