Journal: Toxins

Article Title: Stability and Safety of Inhibitor Cystine Knot Peptide, GTx1-15, from the Tarantula Spider Grammostola rosea

doi: 10.3390/toxins13090621

Figure Lengend Snippet: Representative structure of knottin and GTx1-15. ( A ) Cartoon represents peptide backbone and disulfide-bonded cystine-knot core. Red bars indicate disulfide bond connectivity. ( B ) Three-dimensional structure model and amino acid sequence of GTx1-15. 3D structure model of GTx1-15 was constructed via homology modeling with ICM-PRO (Molsoft, La Jolla, CA, USA) based on NMR structures of HnTx-IV (PDB: 1niy). Red letters indicate cysteine residues and red bars indicate disulfide bond connectivity.

Article Snippet: GTx1-15 was obtained from Alomone Labs (Jerusalem, Israel).

Techniques: Sequencing, Construct

Journal: Toxins

Article Title: Stability and Safety of Inhibitor Cystine Knot Peptide, GTx1-15, from the Tarantula Spider Grammostola rosea

doi: 10.3390/toxins13090621

Figure Lengend Snippet: Stability of GTx1-15 in rat or human plasma. GTx1-15 was incubated in rat plasma ( A ) and in human plasma ( B ). No degradation was observed in either rat or human plasma in vitro for 24 h. Results are means ± SEM, n = 3. Note that error bars are too small to be visible.

Article Snippet: GTx1-15 was obtained from Alomone Labs (Jerusalem, Israel).

Techniques: Incubation, In Vitro

Journal: Toxins

Article Title: Stability and Safety of Inhibitor Cystine Knot Peptide, GTx1-15, from the Tarantula Spider Grammostola rosea

doi: 10.3390/toxins13090621

Figure Lengend Snippet: Plasma concentrations of GTx1-15 after i.v. or i.m. administration in rats. ( A ) GTx1-15 concentrations in rat blood after i.v. administration of 0.1 mg/kg or 0.5 mg/kg. GTx1-15 dropped below the detection limit in 4 or 8 h. ( B ) GTx1-15 concentration in rat blood after i.m. administration of 0.1 mg/kg or 0.5 mg/kg. The peak concentration of GTx1-15 in rat blood circulation was detected at 15 min after 0.1 mg/kg administration and at 30 min and 1 h after 0.5 mg/kg administration. Results are means ± SEM, n = 3. The dotted line indicates the detection limit of GTx1-15 (10 ng/mL) in blood circulation. No animals administered with GTx1-15 via i.v. or i.m. showed any abnormal behavior throughout the experiments.

Article Snippet: GTx1-15 was obtained from Alomone Labs (Jerusalem, Israel).

Techniques: Concentration Assay

Journal: Toxins

Article Title: Stability and Safety of Inhibitor Cystine Knot Peptide, GTx1-15, from the Tarantula Spider Grammostola rosea

doi: 10.3390/toxins13090621

Figure Lengend Snippet: Thermal stability of GTx1-15. The calculated chromatogram peak area after incubation at the indicated temperatures for 24 h are shown. GTx1-15 did not degrade at 20 °C, 37 °C or 50 °C. At 75 °C, GTx1-15 degraded about 5%, but not significantly. About a 30% degradation of GTx1-15 was observed at 95 °C. Experiments were repeated in duplicate, and results are indicated as means ± SEM, n = 3. Statistical significance was determined by Dunnett’s multiple test, and p values < 0.05 were considered significant. ** indicates a significant difference p < 0.01.

Article Snippet: GTx1-15 was obtained from Alomone Labs (Jerusalem, Israel).

Techniques: Incubation

Journal: Toxins

Article Title: Stability and Safety of Inhibitor Cystine Knot Peptide, GTx1-15, from the Tarantula Spider Grammostola rosea

doi: 10.3390/toxins13090621

Figure Lengend Snippet: Protein thermal shift assay.

Article Snippet: GTx1-15 was obtained from Alomone Labs (Jerusalem, Israel).

Techniques:

Journal: Toxins

Article Title: Stability and Safety of Inhibitor Cystine Knot Peptide, GTx1-15, from the Tarantula Spider Grammostola rosea

doi: 10.3390/toxins13090621

Figure Lengend Snippet: Cytotoxicity of GTx1-15. The effect of GTx1-15 on THP-1 cells after a 24-h exposure is shown. After 2 h of WST-1 incubation, the absorbance at 450 nm was measured by a plate reader. No effect of GTx1-15 was observed. Data are means ± SEM, n = 8.

Article Snippet: GTx1-15 was obtained from Alomone Labs (Jerusalem, Israel).

Techniques: Incubation

Journal: Toxins

Article Title: Stability and Safety of Inhibitor Cystine Knot Peptide, GTx1-15, from the Tarantula Spider Grammostola rosea

doi: 10.3390/toxins13090621

Figure Lengend Snippet: Antigenicity of GTx1-15. The effect of GTx1-15 on THP-1 cells after a 24-h exposure is shown. The expressions of CD80, CD86 and CD54 were quantified by RT-PCR using primers listed in . No effect of GTx1-15 was observed on CD80 expression ( A ), CD86 expression ( B ), or CD54 expression ( C ). Data are means ± SEM, n = 3. Experiments were repeated in triplicate.

Article Snippet: GTx1-15 was obtained from Alomone Labs (Jerusalem, Israel).

Techniques: Reverse Transcription Polymerase Chain Reaction, Expressing

Journal: Toxins

Article Title: Stability and Safety of Inhibitor Cystine Knot Peptide, GTx1-15, from the Tarantula Spider Grammostola rosea

doi: 10.3390/toxins13090621

Figure Lengend Snippet: Comparison of GTx1-15 and ω-hexatoxin-Hv1a. ( A ) Amino acid comparison of GTx1-15 and ω-hexatoxin-Hv1a. Cysteine residues are indicated in bold letters. Note that ω-hexatoxin-Hv1a contains a long loop in the C-terminal region of the molecule (amino acid residues shown in red). Hydrophobic amino acid residues are shown in red bold letters. ( B ) 3D structure comparison of GTx1-15 and ω-hexatoxin-Hv1a. 3D structure models of GTx1-15 was constructed by homology modeling with ICM-PRO (Molsoft, La Jolla, CA) based on NMR structures of HnTx-IV (PDB: 1niy). 3D structure of ω-hexatoxin-Hv1a is based on PDB No. 1AXH. The long loop part of ω-hexatoxin-Hv1a (the area circled in red) protrudes from the main body consisting of three disulfide bonds (the area circled in blue). However, the very small loop part of GTx1-15 (the area circled in black) is different from the ω-hexatoxin-Hv1a long loop. The hydrophobic amino acid residues shown in red bold in ( A ) are indicated by a single letter at the corresponding position on the ribbon. All hydrophobic amino acid residues are located outside of the blue circle. However, tryptophan, a hydrophobic amino acid residue shown as a bold letter in the small loop of GTx1-15, is located inside the blue loop.

Article Snippet: GTx1-15 was obtained from Alomone Labs (Jerusalem, Israel).

Techniques: Construct