Sensing PEGylated Peptide Conformations Using a Protein Nanopore.
Nano Lett
; 24(12): 3566-3574, 2024 Mar 27.
Article
in En
| MEDLINE
| ID: mdl-38316144
ABSTRACT
Membrane pores are exploited for the stochastic sensing of various analytes, and here, we use electrical recordings to explore the interaction of PEGylated peptides of different sizes with a protein pore, CymA. This wide-diameter natural pore comprises densely filled charged residues, facilitating electrophoretic binding of polyethylene glycol (PEG) tagged with a nonaarginine peptide. The small PEG 200 peptide conjugates produced monodisperse blockages and exhibited voltage-dependent translocation across the pores. Notably, the larger PEG 1000 and 2000 peptide conjugates yielded heterogeneous blockages, indicating a multitude of PEG conformations hindering their translocation through the pore. Furthermore, a much larger PEG 5000 peptide occludes the pore entrance, resulting in complete closure. The competitive binding of different PEGylated peptides with the same pore produced specific blockage signals reflecting their identity, size, and conformation. Our proposed model of sensing distinct polypeptide conformations corresponds to disordered protein unfolding, suggesting that this pore can find applications in proteomics.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Nanopores
Language:
En
Journal:
Nano Lett
Year:
2024
Document type:
Article