Temporins, Small Antimicrobial Peptides with Leishmanicidal Activity

Synthesis and antimicrobial activity of dermaseptin S1 analogues

“…These results demonstrate that in this assay shortening of the C-terminal peptide sequence seems to have a detrimental effect against the leishmanicidal activity and the sequence 1-29 appears to be the minimal active fragment. Compounds DS1(1-29)-NH 2 had a LC 50 similar or marginally increased to that of DS1 and dermaseptin S4 as reported by Gaidukov et al 24 on L. major, and also increased compared to temporins A and B reported by Mangoni et al 29 on L. donovani. Moreover, leishmanicidal activity was observed at concentrations significantly lower than RBC cytotoxic concentrations indicating more selectivity compared to the dermaseptin analogues tested by Gaidukov et al 24 The antimicrobial activity observed by some of the synthetic compounds tested are similar to those obtained by other authors with defensins 30 and with peptides purified from Phyllomedusa distincta.…”

“…Similarly, Brand et al 9 demonstrated an anti-protozoal activity against Trypanosoma cruzi by DS01 (29-residue peptide) and by two synthetic derivatives, without a toxicity against mouse erythrocytes and white blood cells. The observed activity seems superior to that reported by Mangoni et al 29 for temporins (from Rana temporaria).…”

Primaquine revisited six decades after its discovery

“…Thus, electrostatic interactions between the positively charged drug and the negatively charged headgroups seem to be the initial step of drug interaction with the protozoan cell surface, after which hydrophobic interactions between the drug's aromatic ring and the phospholipid's inner core of alkyl chains take place, leading to drug insertion [43]. So it seems that sitamaquine exerts its anti-protozoan action in a fashion similar to that of antimicrobial peptides, many of them also reported as promising leishmanicidal agents [231][232][233]. …”

Interaction of Antimicrobial Peptide Temporin L with Lipopolysaccharide In Vitro and in Experimental Rat Models of Septic Shock Caused by Gram-Negative Bacteria

“…They are generally most active against gram-positive bacteria, but some show considerable activity also against gram-negative bacteria and fungal pathogens, including Candida albicans and Batrachochytrium dendrobatidis, a pathogen associated with global amphibian declines (33,44,45,49). Furthermore, selected temporins have been recently shown to exert a potent killing activity against the human parasitic protozoan Leishmania (34). Studies aimed at understanding the killing mechanism of temporins have ascertained that these peptides alter the permeability of bacterial cell membrane in a dose-dependent manner without destroying cell integrity, leading to leakage of cytosolic content and cell death (32).…”

“…1) as a working model. Indeed, this peptide proved to have the highest antimicrobial potency among tested temporins, especially against gram-negative bacteria, and was therefore subjected to in-depth investigation to understand its mode(s) of action (32,34,44,58,59). However, no information is currently available for this molecule-and for temporins in general-as for its interactions with the outer membrane of gram-negative bacteria and thus its ability to bind and neutralize endotoxin.…”