Journal: Pathogens

Article Title: Design and Characterization of an HRC-Derived Peptide Inhibitor of Canine Coronavirus Spike-Mediated Fusion

doi: 10.3390/pathogens15030315

Figure Lengend Snippet: Evaluation of cell viability after 24 h of treatment with CCoV-HRC using the MTT assay. ( A ) Dose–response curve in HEK-293T cells. ( B ) Dose–response curve in A72 cells. The positive control (CTRL+) corresponds to untreated cells, whereas the negative control (CTRL−) corresponds to cells treated with 100% DMSO. Cell viability is expressed as a percentage relative to the positive control. Data are presented as mean ± standard deviation (SD) of three independent experiments. Statistical analysis was performed using one-way ANOVA, followed by Dunnett’s post hoc test: **** p < 0.0001, *** p = 0.0002, * p = 0.0332, ns = not significant.

Article Snippet: The CCoV-HRC peptide was synthesized by Synpeptide Co. (Shanghai, China).

Techniques: MTT Assay, Positive Control, Negative Control, Standard Deviation

Journal: Pathogens

Article Title: Design and Characterization of an HRC-Derived Peptide Inhibitor of Canine Coronavirus Spike-Mediated Fusion

doi: 10.3390/pathogens15030315

Figure Lengend Snippet: Antiviral activity of CCoV-HRC during in vitro CCoV infection in A72 cells. The % of viral inhibition was calculated using the TCID 50 assay in virus pre-treatment experiments. Oreoch-1 peptide was used as a positive control (CTRL+) , whereas untreated and infected cells served as the negative control (CTRL−). The scrambled peptide (sequence: ENLLVLNNATLTFITEDNITIFLIRSENLNEHYLAENLTDVGLNKWID) was also added to the test, without reducing viral infectivity, confirming the sequence-specific activity of CCoV-HRC. Statistical analysis was performed by one-way ANOVA followed by Dunnett’s post hoc test. Significance compared to CTRL− (black lines) was **** p < 0.0001 and * p = 0.0332, while compared to CTRL+ (blue lines) was ns = 0.1234, * p = 0.0021, **** p < 0.0001.

Article Snippet: The CCoV-HRC peptide was synthesized by Synpeptide Co. (Shanghai, China).

Techniques: Activity Assay, In Vitro, Infection, Inhibition, Virus, Positive Control, Negative Control, Sequencing

Journal: Pathogens

Article Title: Design and Characterization of an HRC-Derived Peptide Inhibitor of Canine Coronavirus Spike-Mediated Fusion

doi: 10.3390/pathogens15030315

Figure Lengend Snippet: Quantitative real-time PCR analysis of CCoV S gene expression following virus pre-treatment with CCoV-HRC. One-way ANOVA followed by Dunnett’s multiple comparisons test was performed, ** p = 0.0021, ns = not significant.

Article Snippet: The CCoV-HRC peptide was synthesized by Synpeptide Co. (Shanghai, China).

Techniques: Real-time Polymerase Chain Reaction, Gene Expression, Virus

Journal: Pathogens

Article Title: Design and Characterization of an HRC-Derived Peptide Inhibitor of Canine Coronavirus Spike-Mediated Fusion

doi: 10.3390/pathogens15030315

Figure Lengend Snippet: Docking results of the S protein of CCoV S378 ( A ), CCoV-HuPn-2018 ( B ), and SARS-CoV-2 ( C ) with the HRC peptide. The S protein chains of the trimer are shown in blue (chain A), green (chain B), and orange (chain C), while the CCoV-HRC peptide is represented as a magenta cartoon. ( A ) The HRC peptide binds to CCoV S378 between chain A (S2 subunit) and chain C (S1 subunit). ( B ) In HuPn-2018, the HRC peptide binds to the viral S1 subunit. ( C ) Finally, in SARS-CoV-2, the peptide binds to chain A between S1 and S2. Subunit identification was performed according to Tortorici et al. .

Article Snippet: The CCoV-HRC peptide was synthesized by Synpeptide Co. (Shanghai, China).

Techniques:

Journal: Pathogens

Article Title: Design and Characterization of an HRC-Derived Peptide Inhibitor of Canine Coronavirus Spike-Mediated Fusion

doi: 10.3390/pathogens15030315

Figure Lengend Snippet: Individual structural models of the HR1–HR2 post-fusion cores from CCoV-S378, CCoV-HuPn-2018, and SARS-CoV-2, highlighting the CCoV-HRC peptide (magenta) bound antiparallel to the central HR1 coiled coil.

Article Snippet: The CCoV-HRC peptide was synthesized by Synpeptide Co. (Shanghai, China).

Techniques:

Journal: Pathogens

Article Title: Design and Characterization of an HRC-Derived Peptide Inhibitor of Canine Coronavirus Spike-Mediated Fusion

doi: 10.3390/pathogens15030315

Figure Lengend Snippet: Stability and kinetic analysis of CoV core complexes. ( A ) RMSD and ( B ) RoG were calculated for the CCoV S378 core (blue), CCoV-HuPn-2018_core (orange), and SARS-CoV-2_core (green) complexes with the CCoV-HRC peptide over 10 ns of MDS. As shown in ( A ), the SARS-CoV-2 core complex reaches thermodynamic stability later compared to the other two complexes. RoG analysis ( B ) indicates that while the core conformation remained largely constant during the MD simulation in CCoV S378_and CCoV-HuPn-2018, it decreased in SARS-CoV-2, suggesting a more compact structure. ( C ) RMSF analysis of the three complexes shows the flexibility of individual atoms of the CCoV-HRC peptide. The X-axis represents the atom number of the HRC peptide, while the Y-axis represents atomic fluctuations in nanometers (nm). The results indicate that the HRC peptide exhibits greater flexibility—and thus lower stability—when bound to the SARS-CoV-2_core complex compared to the other cores. ( D ) H-bond kinetic analysis summary. This table provides a summary of the hydrogen bond dynamics for the three core complexes, including forward and backward rates, relaxation times, characteristic times, and the free energy changes (ΔG) associated with hydrogen bond formation and dissociation.

Article Snippet: The CCoV-HRC peptide was synthesized by Synpeptide Co. (Shanghai, China).

Techniques: