Electrophysiological Analysis of Antimicrobial Peptides in Diverse Species

Saigo, Naoki; Izumi, Kayano; Kawano, Ryuji

doi:10.1021/acsomega.9b01033

“…The representative observations of electrophysiological measurements are shown in Figure 3 c. Briefly, cell penetrating peptides (CPPs) exhibit step-like signals [ 16 ]. In contrast, the toroidal pore model exhibits multilevel current signals [ 17 , 18 ]. Based on this knowledge, we performed electrophysiological measurement against 1,2-dioleoyl- sn -glycero-3-phosphoethanolamine (DOPE)/1,2-dioleoyl- sn -glycero-3-phospho-(1′- rac -glycerol) (DOPG) and 1,2-dioleoyl- sn -glycero-3-phosphocholine (DOPC) bilayer membranes, which mimic the microbial and mammalian cell membranes, respectively, to investigate the action mechanisms on the antimicrobial and hemolytic activities of peptides 1 , 2 , and 8 .…”

Section: Resultsmentioning

confidence: 99%

“…Furthermore, treatment of peptide 8 showed a subsequent increase in current signals, which indicates that this peptide could form a pore in the DOPC membrane. It has been reported that the antimicrobial activities of AMPs are positively correlated with the scores for each pore-forming parameter, including pore stability, pore diameter, charge flux, and pore-forming activity [ 18 ]. Each parameter was evaluated as previously reported [ 18 ].…”

Section: Resultsmentioning

confidence: 99%

“…It has been reported that the antimicrobial activities of AMPs are positively correlated with the scores for each pore-forming parameter, including pore stability, pore diameter, charge flux, and pore-forming activity [ 18 ]. Each parameter was evaluated as previously reported [ 18 ]. The total score of peptides 1 , 2 , and 8 was determined to detect their pore-forming activity.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Development of Antimicrobial Stapled Peptides Based on Magainin 2 Sequence

Hirano

¹

,

Saito

²

,

Yokoo

³

et al. 2021

Self Cite

View full text Add to dashboard Cite

Magainin 2 (Mag2), which was isolated from the skin of the African clawed frog, is a representative antimicrobial peptide (AMP) that exerts antimicrobial activity via microbial membrane disruption. It has been reported that the helicity and amphipathicity of Mag2 play important roles in its antimicrobial activity. We investigated and recently reported that 17 amino acid residues of Mag2 are required for its antimicrobial activity, and accordingly developed antimicrobial foldamers containing α,α-disubstituted amino acid residues. In this study, we further designed and synthesized a set of Mag2 derivatives bearing the hydrocarbon stapling side chain for helix stabilization. The preferred secondary structures, antimicrobial activities, and cell-membrane disruption activities of the synthesized peptides were evaluated. Our analyses revealed that hydrocarbon stapling strongly stabilized the helical structure of the peptides and enhanced their antimicrobial activity. Moreover, peptide 2 stapling between the first and fifth position from the N-terminus showed higher antimicrobial activity than that of Mag2 against both gram-positive and gram-negative bacteria without exerting significant hemolytic activity. To investigate the modes of action of tested peptides 2 and 8 in antimicrobial and hemolytic activity, electrophysiological measurements were performed.

show abstract

“…We have previously proposed current signal classification for several different signal shapes, and assigned these to various pore-forming models of α-helical peptides. [50][51][52] In this study, we also classified these signals into four types of current signals: step, square-top, multi-level, and erratic. The definition of signal classification is described in Fig.…”

Section: Confirmation Of Pore Formation Using Channel Current Measurementioning

confidence: 99%

De Novo Design of a Nanopore for DNA Detection Incorporating a β-hairpin Peptide

Shimizu¹,

Mijiddorj²,

Yoshida³

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

The amino acid sequence of a protein encodes information on its three-dimensional structure and specific functionality. De novo protein design has emerged as a method to manipulate the primary structure for the development of artificial proteins and peptides with desired functionality. This paper describes the de novo design of a pore-forming peptide that has a β-hairpin structure and assembles to form a stable nanopore in a bilayer lipid membrane. This large synthetic nanopore is an entirely artificial device with practical applications. This peptide, named SV28, forms nanopore structures ranging from 1.6 to 6.2 nm in diameter assembled from 7 to 18 monomers. The nanopore formed with a diameter of 5 nm is able to detect long double-stranded DNA (dsDNA) with 1 kbp length, and measurement of current signals allowed us to investigate the translocation behavior of dsDNA at the single molecule level. Such de novo design of peptide sequences has the potential to create assembled structure in lipid membrane such as novel nanopores, which would also be applicable in molecular transporter between inside and outside of lipid membrane.

show abstract

“…We have previously proposed current signal classification for several different signal shapes, and assigned these to various pore-forming models of α-helical peptides. 50,51,52 In this study, we also classified these signals into four types of current signals: step, square-top ( Fig. 3c), multi-level, and erratic (Fig.…”

Section: Confirmation Of Pore Formation Using Channel Current Measurementioning

confidence: 99%

De Novo Design of a Nanopore for DNA Detection Incorporating a β-hairpin Peptide

Shimizu¹,

Mijiddorj²,

Yoshida³

et al. 2020

Preprint

Self Cite

View full text Add to dashboard Cite

The amino acid sequence of a protein encodes information on its three-dimensional structure and specific functionality. De novo protein design has emerged as a method to manipulate the primary structure for the development of artificial proteins and peptides with desired functionality. This paper describes the de novo design of a pore-forming peptide that has a β-hairpin structure and assembles to form a stable nanopore in a bilayer lipid membrane. This large synthetic nanopore is an entirely artificial device with practical applications. This peptide, named SV28, forms nanopore structures ranging from 1.6 to 6.2 nm in diameter assembled from 7 to 18 monomers. The nanopore formed with a diameter of 5 nm is able to detect long double-stranded DNA (dsDNA) with 1 kbp length, and measurement of current signals allowed us to investigate the translocation behavior of dsDNA at the single molecule level. Such de novo design of peptide sequences has the potential to create assembled structure in lipid membrane such as novel nanopores, which would also be applicable in molecular transporter between inside and outside of lipid membrane.

show abstract

Electrophysiological Analysis of Antimicrobial Peptides in Diverse Species

Cited by 22 publications

References 47 publications

Development of Antimicrobial Stapled Peptides Based on Magainin 2 Sequence

Development of Antimicrobial Stapled Peptides Based on Magainin 2 Sequence

De Novo Design of a Nanopore for DNA Detection Incorporating a β-hairpin Peptide

De Novo Design of a Nanopore for DNA Detection Incorporating a β-hairpin Peptide

Contact Info

Product

Resources

About