Peptide name : Lycosin-I

Source/Organism : Wolf spider

Linear/Cyclic : Linear

Chirality : Not found

Peptide length: Not available

C-terminal modification: Linear

N-terminal modification : Free

Non-natural peptide information: None

Assay type : Not specified

Assay time : Not found

Activity : Not found

Cell line : Not found

Cancer type : Not specified

Other activity : Anti-microbial activity

Amino Acid Composition Bar Chart : Not available

Molecular mass : Not available

Aliphatic index : Not available

Instability index : Not available

Hydrophobicity (GRAVY) : Not available

Isoelectric point : Not available

Charge (pH 7) : Not available

Aromaticity : Not available

Molar extinction coefficient (cysteine, cystine): Not available

Hydrophobic/hydrophilic ratio : Not available

hydrophobic moment : Not available

Missing amino acid : Not available

Most occurring amino acid : Not available

Most occurring amino acid frequency : Not available

Least occurring amino acid : Not available

Least occurring amino acid frequency : Not available

3D-structure: Not available

Secondary structure fraction (Helix, Turn, Sheet): Not available

SMILES Notation: Not available

Molecular descriptors: Not available

ADMET properties: Not available

1 : Ma B, et al. Vasodilator and hypotensive effects of the spider peptide Lycosin-I in vitro and in vivo. Peptides. 2018; 99:108-114. doi: 10.1016/j.peptides.2017.12.011

2 : Tang Y, et al. Anti-parasitic effect on Toxoplasma gondii induced by a spider peptide lycosin-I. Exp Parasitol. 2019; 198:17-25. doi: 10.1016/j.exppara.2019.01.009

3 : Tan H, et al. Quantifying the Distribution of the Stoichiometric Composition of Anticancer Peptide Lycosin-I on the Lipid Membrane with Single Molecule Spectroscopy. J Phys Chem B. 2016; 120:3081-8. doi: 10.1021/acs.jpcb.5b12618

4 : Tan L, et al. Antifungal activity of spider venom-derived peptide lycosin-I against Candida tropicalis. Microbiol Res. 2018; 216:120-128. doi: 10.1016/j.micres.2018.08.012

5 : Tan H, et al. Antimicrobial potential of lycosin-I, a cationic and amphiphilic peptide from the venom of the spider Lycosa singorensis. Curr Mol Med. 2013; 13:900-10. doi: 10.2174/15665240113139990045

Paper title : Vasodilator and hypotensive effects of the spider peptide Lycosin-I in vitro and in vivo.

Doi : https://doi.org/10.1016/j.peptides.2017.12.011

Abstract : Lycosin-I, a spider peptide isolated from the venom of the spider Lycosa singoriensis, has anti-bacteria and anti-cancer properties in organisms. However, cardiovascular effects of Lycosin-I have not been studied. In this study, we investigated for the first time the vasodilator and hypotensive effects of Lycosin-I and the possible mechanisms, in order to develop a promising treatment for hypertension-related diseases. For in vitro experiments, thoracic aortas were isolated, and divided into two groups, endothelium-intact and endothelium-denuded aortic rings. Lycosin-I induced a remarkable dose-dependent relaxation in endothelium-intact aortic rings pre-treated with phenylephrine (p < 0.05), while it showed no obvious vasodilator effects in endothelium-denuded aortic rings (p > 0.05). The vasodilator effects of Lycosin-I were significantly weakened by a nitric oxide synthase (NOS) inhibitor, L-NAME (p < 0.001) and a selective inhibitor of nitric oxide (NO)-sensitive soluble guanylate cyclase (sGC), ODQ (p < 0.05), respectively. The levels of endothelial nitric oxide synthase (eNOS) phosphorylation and the NO production were significantly higher in human umbilical vascular endothelial cells pre-cultured with Lycosin-I than the control (p < 0.001), determined via western blot analysis and ozone-chemiluminescence technology. For in vivo experiments, arterial and venous catheters were inserted for mean arterial pressure (MAP) recording and drug administration in anaesthetized spontaneously hypertensive rats. Lycosin-I caused a transient drop of MAP 2 min after the administration compared with the control (p < 0.001). In conclusion, Lycosin-I has the potential to be an anti-hypertensive drug by endothelium-dependent vasodilatation, in which eNOS and NO-sensitive sGC are two main involved factors.

Paper title : Anti-parasitic effect on Toxoplasma gondii induced by a spider peptide lycosin-I.

Doi : https://doi.org/10.1016/j.exppara.2019.01.009

Abstract : Toxoplasmosis is a widely distributed parasitic protozoan disease, caused by Toxoplasma gondii (T. gondii). High prevalence of toxoplasmosis and limitations of conventional treatments lead to a search for new therapeutic drugs. Lycosin-I is a linear peptide, derived from the venom of the spider Lycosa singoriensis. The aim of the present study was to determine the anti-parasitic effect of lycosin-Ι against T. gondii. In vitro, the anti-T. gondii activities of lycosin-Ι were evaluated by MTT assay, trypan blue exclusion assay, cell counting assay and plaque assay. Cytokines of IL-6 and IL-8 were measured by quantitative PCR. In addition, the structures of tachyzoites treated with lycosin-Ι were also observed by scanning and transmission electron microscopy. In vivo, mice were challenged with parasites treated by lycosin-I. The results revealed that lycosin-Ι had shown a significant ability to inhibit T. gondii invasion and proliferation. Cytokines of IL-6 and IL-8 were reduced by lycosin-Ι at transcription level in human foreskin fibroblast (HFF) cells infected with T. gondii tachyzoites, but they were increased compared to non-infected cells. For tachyzoites, lycosin-Ι induced their cell membrane alterations with formation of invaginations, some of them appeared to be vacuolated in their cytoplasm. Moreover, lycosin-Ι had prolonged the survival time of mice by controlling T. gondii proliferation. In conclusion, our present study provides the first evidence for anti-T. gondii by using the spider peptide lycosin-Ι. These findings suggest that lycosin-Ι is a potential alternative agent for the treatment of toxoplasmosis.

Paper title : Quantifying the Distribution of the Stoichiometric Composition of Anticancer Peptide Lycosin-I on the Lipid Membrane with Single Molecule Spectroscopy.

Doi : https://doi.org/10.1021/acs.jpcb.5b12618

Abstract : Lycosin-I, a peptide toxin derived from spider venom, has been demonstrated to be a promising candidate for the inhibition of tumor cell growth in vitro and in vivo by interacting with and penetrating the cell membrane. Owing to the shortage of an efficient characterization strategy, however, there is still a lack of detailed knowledge about the distribution of the stoichiometric composition information on this peptide in solution and on lipid membrane prior to the cellular uptake process, which is fundamentally important for the understanding of the anticancer mechanism. In this work, with objective-type total internal reflection fluorescence microscopy (TIRF), the distribution of the stoichiometric composition of lycosin-I in different solutions as well as on the lipid membrane was explored extensively on the basis of a statistical single molecule fluorescence intensity analysis for the first time. It was found that lycosin-I is mainly present in a monomer state in diverse physiological solutions regardless of the concentration of the peptide and the incubation time. However, on the lipid membrane, the fraction of small size oligomers increased as a function of time. Fusion of movable peptide molecules to those peptide oligomers with restricted motion on the lipid membrane was also observed.

Paper title : Antifungal activity of spider venom-derived peptide lycosin-I against Candida tropicalis.

Doi : https://doi.org/10.1016/j.micres.2018.08.012

Abstract : Candida species are a major cause of human mucosal and deep tissue fungal infections, but few antifungal treatments are available. Here, we showed that lycosin-I, a peptide isolated from venom of the spider Lycosa singoriensis, acted as a potent antifungal inhibitor against Candida species. The MIC₅₀ values of lycosin-I reached 8 μg/mL to treat fluconazole-susceptible and fluconazole-resistant C. tropicalis isolates. Time-kill kinetics assays revealed that after a 2-hour exposure, lycosin-I reduced colony-forming units/mL in fluconazole-susceptible and fluconazole-resistant C. tropicalis isolates approximately 70%. Furthermore, salinity tolerance assays suggested that even in the presence of Mg2+, lycosin-I maintained its potent antifungal ability at a high concentration. When the concentration of lycosin-I was increased from 1 × MIC to 8 × MIC, a significant decrease of the biofilm metabolic activity was observed in both fluconazole-susceptible and fluconazole-resistant C. tropicalis isolates. Moreover, the biofilm inhibitory concentration 50 (BIC₅₀) and the biofilm eradicating concentration 50 (BEC₅₀) were approximately 32 μg/mL and 128 μg/mL, respectively. Confocal laser scanning microscopy showed the localization of CY5-labeled lycosin-I mainly in the cell cytoplasm, and lycosin-I was likely to be localized in the cytoplasm after its transportation across the cell wall and membrane. Overall, our work shows that lycosin-I is a potent antifungal agent with a high efficacy, a high salinity tolerance, and potent anti-biofilm properties.

Paper title : Antimicrobial potential of lycosin-I, a cationic and amphiphilic peptide from the venom of the spider Lycosa singorensis.

Doi : https://doi.org/10.2174/15665240113139990045

Abstract : Antimicrobial peptides (AMPs) are significant components of the innate immune system and play indispensable roles in the resistance to bacterial infection. Here, we investigated the antimicrobial activity of lycosin-I, a 24-residue cationic anticancer peptide derived from Lycosa singorensis with high structural similarity to several cationic and amphiphilic antimicrobial peptides. The antimicrobial activity of lycosin-I against 27 strains of microbes including bacteria and fungi was examined and compared with that of the Xenopus-derived AMP magainin 2 using a microdilution assay. Lycosin-I inhibited the growth of most microorganisms at low micromolar concentrations, and was a more potent inhibitor than magainin 2. Lycosin-I showed rapid, selective and broad-spectrum bactericidal activity and a synergistic effect with traditional antibiotics. In vivo, it showed potent bactericidal activity in a mouse thigh infection model. High Mg2+ concentrations reduced the antibacterial effect of lycosin-I, implying that the peptide might directly interact with the bacterial cell membrane. Uptake of the fluorogenic dye SYTOX and changes in the surface of lycosin-Itreated bacterial cells observed by scanning electron microscopy confirmed that lycosin-I permeabilized the cell membrane, resulting in the rapid bactericidal effect. Taken together, our findings indicate that lycosin-I is a promising peptide with the potential for the development of novel antibacterial agents.