Single-Molecule Study of Peptides with the Same Amino Acid Composition but Different Sequences by Using an Aerolysin Nanopore.
Chembiochem
; 21(17): 2467-2473, 2020 09 01.
Article
em En
| MEDLINE
| ID: mdl-32274877
ABSTRACT
Nanopores are original sensors employed for highly sensitive peptides/proteins detection. Herein, we describe the use of an aerolysin nanopore to identify two similar model peptides, YEQYEQQDDDRQQQ (YEQ2Q3) and QDDDRQQQYEQYEQ (Q3YEQ2), with the same amino acid composition but different sequences. All-atom molecular dynamics (MD) simulations reveal that YEQ2Q3 possesses fewer hydrogen bonds and a more extended conformation than Q3YEQ2. These two peptides, which fold differently, exhibit obviously distinct mass-independent current blockades with characteristic dwell times when entering the aerolysin nanopore. Typically, at +60â
mV, the statistical dwell time of 0.630±0.018â
ms for peptide Q3YEQ2 is four times longer than the value of 0.160±0.001â
ms for peptide YEQ2Q3, and yet peptide YEQ2Q3 induces â¼1.9 % larger blockade current amplitude than peptide Q3YEQ2. The obtained results show the remarkable potential of aerolysin nanopore for peptides/proteins identification, characterization, sequencing and also demonstrate that the mass identification of nonuniformly charged peptides/proteins by using the nanopore technique could be complicated by their folded structure and complex analyte-pore interaction.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
/
Toxinas Bacterianas
/
Proteínas Citotóxicas Formadoras de Poros
/
Nanoporos
/
Aminoácidos
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Chembiochem
Ano de publicação:
2020
Tipo de documento:
Article