Fibril-mediated oligomerization of pilin-derived protein nanotubes

Journal of Nanobiotechnology

Research

Anna Petrov¹  Stephanie Lombardo¹  Gerald F Audette² 

[1] Department of Chemistry, York University, M3J1P3, Toronto, ON, Canada;Department of Chemistry, York University, M3J1P3, Toronto, ON, Canada;Centre for Research on Biomolecular Interactions, York University, Toronto, Canada;

关键词: Protein nanotubes;    Type IV pilin;    Type IV pilus;    Protein oligomerization;   

DOI  :  10.1186/1477-3155-11-24

 received in 2013-05-03, accepted in 2013-07-01,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundSelf-assembling protein nanotubes (PNTs) are an intriguing alternative to carbon nanotubes for applications in bionanotechnology, in part due to greater inherent biocompatibility. The type IV pilus of the gram negative bacteria Pseudomonas aeruginosa is a protein-based fibre composed of a single subunit, the type IV pilin. Engineered pilin monomers from P. aeruginosa strain K122-4 (ΔK122) have been shown to oligomerize into PNTs both in solution and at surfaces. In order to fully exploit PNTs in bionanotechonological settings, an in-depth understanding of their assembly, physical characteristics and robustness, both in solution and when constrained to surfaces, is required.ResultsThis study details the effectiveness of multiple initiators of ΔK122-derived PNT oligomerization and characterize the formation of PNTs in solution. The optimal initiator for the oligomerization of ΔK122 in solution was observed to be 2-methyl-2,4-pentanediol (MPD). Conversely, larger PEG molecules do not trigger oligomerization. Multi-angle light scattering analysis indicates that the pilin protein exists in a monomer-dimer equilibrium in solution, and that an intermediate species forms within three hours that then coalesces over time into high molecular weight PNTs. Transmission Electron Microscopic analysis was used to observe the formation of oligomerized ΔK122 fibrils prior to assembly into full-length PNTs.ConclusionsThe oligomerization of ΔK122 pilin derived PNTs is a fibril mediated process. The optimal trigger for PNT oligomerization in solution is MPD, and the observation that PEGs do not induce oligomerization may enable the oligomerization of pilin-derived PNTs on PEG-functionalized surfaces for implantable bionanodevices.

【 授权许可】

Unknown   
© Petrov et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.