Ulster University Logo

A family of antimicrobial and immunomodulatory peptides related to the frenatins from skin secretions of the Orinoco lime frog Sphaenorhynchus lacteus (Hylidae)

Conlon, J. Michael, Mechkarska, Milena, Radosavljevic, Gordana, Attoub, Samir, King, Jay D., Lukic, Miodrag L. and McClean, Stephen (2014) A family of antimicrobial and immunomodulatory peptides related to the frenatins from skin secretions of the Orinoco lime frog Sphaenorhynchus lacteus (Hylidae). Peptides, 56 . 132 - 140. [Journal article]

Full text not available from this repository.

URL: http://www.sciencedirect.com/science/article/pii/S0196978114001053

DOI: http://dx.doi.org/10.1016/j.peptides.2014.03.020

Abstract

Peptidomic analysis of norepinephrine-stimulated skin secretions of the Orinoco lime tree frog Sphaenorhynchus lacteus (Hylidae, Hylinae) revealed the presence of three structurally related host-defense peptides with limited sequence similarity to frenatin 2 from Litoria infrafrenata (Hylidae, Pelodryadinae) and frenatin 2D from Discoglossus sardus (Alytidae). Frenatin 2.1S (GLVGTLLGHIGKAILG.NH2) and frenatin 2.2S (GLVGTLLGHIGKAILS.NH2) are C-terminally α-amidated but frenatin 2.3S (GLVGTLLGHIGKAILG) is not. Frenatin 2.1S and 2.2S show potent bactericidal activity against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MIC ≤16 μM) but are less active against a range of Gram-negative bacteria. Frenatin 2.1S (LC50 = 80 ± 6 μM) and 2.2S (LC50 = 75 ± 5 μM) are cytotoxic against non-small cell lung adenocarcinoma A549 cells but are less hemolytic against human erythrocytes (LC50 = 167 ± 8 μM for frenatin 2.1S and 169 ± 7 μM for 2.2S). Weak antimicrobial and cytotoxic potencies of frenatin 2.3S demonstrate the importance of C-terminal α-amidation for activity. Frenatin 2.1S and 2.2S significantly (P < 0.05) increased production of proinflammatory cytokines IL-1β and IL-23 by lipopolysaccharide (LPS)-stimulated mouse peritoneal macrophages and frenatin 2.1S also enhanced production of TNF-α. Effects on IL-6 production were not significant. Frenatin 2.2S significantly downregulated production of the anti-inflammatory cytokine IL-10 by LPS-stimulated cells. The data support speculation that frenatins act on skin macrophages to produce a cytokine-mediated stimulation of the adaptive immune system in response to invasion by microorganisms. They may represent a template for the design of peptides with therapeutic applications as immunostimulatory agents.

Item Type:Journal article
Keywords:Cytokine
Faculties and Schools:Faculty of Life and Health Sciences > School of Biomedical Sciences
Faculty of Life and Health Sciences
Research Institutes and Groups:Biomedical Sciences Research Institute
Biomedical Sciences Research Institute > Diabetes
ID Code:29425
Deposited By: Prof Stephen McClean
Deposited On:13 May 2014 10:01
Last Modified:19 Jun 2015 14:48

Repository Staff Only: item control page