Increases in hydrophilicity and charge on the polar face of alyteserin 1c helix change its selectivity towards gram-positive bacteria

dc.contributor.authorLiscano, Yamil
dc.contributor.authorSalamanca, Constain H.
dc.contributor.authorVargas, Lina
dc.contributor.authorCantor, Stefania
dc.contributor.authorLaverde Rojas, Valentina
dc.contributor.authorOñate Garzón, José
dc.date.accessioned2020-02-07T07:00:36Z
dc.date.available2020-02-07T07:00:36Z
dc.date.issued2019-11-27
dc.description.abstractRecently, resistance of pathogens towards conventional antibiotics has increased, representing a threat to public health globally. As part of the fight against this, studies on alternative antibiotics such as antimicrobial peptides have been performed, and it has been shown that their sequence and structure are closely related to their antimicrobial activity. Against this background, we here evaluated the antibacterial activity of two peptides developed by solid-phase synthesis, Alyteserin 1c (WT) and its mutant derivative (ΔM), which shows increased net charge and reduced hydrophobicity. These structural characteristics were modified as a result of amino acid substitutions on the polar face of the WT helix. The minimum inhibitory concentration (MIC) of both peptides was obtained in Gram-positive and Gram-negative bacteria. The results showed that the rational substitutions of the amino acids increased the activity in Gram-positive bacteria, especially against Staphylococcus aureus, for which the MIC was one-third of that for the WT analog. In contrast to the case for Gram-positive bacteria, these substitutions decreased activity against Gram-negative bacteria, especially in Escherichia coli, for which the MIC was eight-fold higher than that exhibited by the WT peptide. To understand this, models of the peptide behavior upon interacting with membranes of E. coli and S. aureus created using molecular dynamics were studied and it was determined that the helical stability of the peptide is indispensable for antimicrobial activity. The hydrogen bonds between the His20 of the peptides and the phospholipids of the membranes should modulate the selectivity associated with structural stability at the carboxy-terminal region of the peptides.es
dc.identifier.issn20796382
dc.identifier.urihttps://repositorio.usc.edu.co/handle/20.500.12421/2555
dc.language.isoenes
dc.publisherMDPI AGes
dc.subjectAntimicrobial peptidees
dc.subjectα-helixes
dc.subjectMembrane modeles
dc.subjectNet chargees
dc.subjectAntimicrobiales
dc.titleIncreases in hydrophilicity and charge on the polar face of alyteserin 1c helix change its selectivity towards gram-positive bacteriaes
dc.typeArticlees

Files

Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
Increases in hydrophilicity and charge on the polar face.pdf
Size:
3.77 MB
Format:
Adobe Portable Document Format
Description:
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description: