sars cov 2 assays  (BPS Bioscience)

Journal: International Journal of Molecular Sciences

Article Title: Artificial Intelligence Reveals Nature: Functional Parallels Between a Designed and a Natural Peptide

doi: 10.3390/ijms262110607

Figure Lengend Snippet: RBD-ACE2 interaction inhibition assays. ( a ) Schematic illustration of ELISA experiment to evaluate the ability of the A13 or Nat1 to prevent the interaction of SARS-CoV-2 S1 protein RBD to human receptor ACE2. First the plates were incubated with immobilized RBD. They were then inoculated with peptides prior to the addition of recombinant human receptor ACE2. ( b ) Inhibition of RBD-ACE2 binding via A13 or Nat1. The level of RBD-ACE2 binding was measured by chemiluminescence. The negative control with no peptide representing RBD-ACE2 interaction was set to 1.00 (3.2 × 10 4 RLU) and other values were normalized to this number. To the same extent, at the concentration of 0.1 µg/mL, both peptides reduced ACE2 binding compared to the control. At 1.0 µg/mL, inhibition was further enhanced. The negative control peptide did not exhibit a notable inhibition. Data represent the mean value from at least three independent experiments. Error bars represent standard deviation. Statistical significance was determined using the nonparametric two-tailed Student’s t -test (**** p ≤ 0.0001).

Article Snippet: The ability of the peptides to block the interaction between the RBD and ACE2 was assessed using a commercial ACE2 inhibition assay kit (BPS Bioscience, San Diego, CA, United States, CAT# 79931).

Techniques: Inhibition, Enzyme-linked Immunosorbent Assay, Incubation, Recombinant, Binding Assay, Negative Control, Concentration Assay, Control, Standard Deviation, Two Tailed Test

Journal: International Journal of Molecular Sciences

Article Title: Artificial Intelligence Reveals Nature: Functional Parallels Between a Designed and a Natural Peptide

doi: 10.3390/ijms262110607

Figure Lengend Snippet: NanoLuc bioreporter assays. ( a ) A schematic illustration for the NanoLuc bioreporter assay to determine SARS-CoV-2 S1 RBD—ACE2 inhibition by A13 or Nat1. ( b ) NanoLuc bioreporter assay indicates that both peptides reduce luciferase complementation to the same extent. The signal value for no peptide control was set to 1.00 (6.30 × 10 5 RLU) and all other values were normalized to it. In cell lysates, A13 and Nat1 both reduced luminescence, indicating inhibition of RBD-ACE2 binding. The negative control peptide had no significant effect. Data represent the mean value from at least three independent experiments. Error bars represent standard deviation. Statistical significance was determined using the nonparametric two-tailed Student’s t -test (**** p ≤ 0.0001, ** p ≤ 0.01).

Article Snippet: The ability of the peptides to block the interaction between the RBD and ACE2 was assessed using a commercial ACE2 inhibition assay kit (BPS Bioscience, San Diego, CA, United States, CAT# 79931).

Techniques: Inhibition, Luciferase, Control, Binding Assay, Negative Control, Standard Deviation, Two Tailed Test

Journal: International Journal of Molecular Sciences

Article Title: Artificial Intelligence Reveals Nature: Functional Parallels Between a Designed and a Natural Peptide

doi: 10.3390/ijms262110607

Figure Lengend Snippet: Pseudovirus infectivity assays. ( a ) A schematic illustration for pseudovirus infectivity assay to determine the inhibition ability of the peptides to prevent psuedovirus to enter the cell. ( b ) Pseudovirus infectivity assays indicates that both peptides exhibit similar effects on pseudovirus infected cells. The signal value for pseudovirus infection with no peptide was set to 1.00 and corresponding values were normalized to it. Cells were incubated with pseudovirus in the absence/presence of A13 or Nat1, and infection was measured using a luciferase reporter. Both peptides reduce pseudovirus entry into ACE2-expressing cells. Neither peptide shows any visible effects on the non-peptide sample. Data represents the mean value from at least three independent experiments. Error bars represent standard deviation. Statistical significance was determined using the nonparametric two-tailed Student’s t -test (**** p ≤ 0.0001, ** p ≤ 0.01).

Article Snippet: The ability of the peptides to block the interaction between the RBD and ACE2 was assessed using a commercial ACE2 inhibition assay kit (BPS Bioscience, San Diego, CA, United States, CAT# 79931).

Techniques: Infection, Inhibition, Incubation, Luciferase, Expressing, Standard Deviation, Two Tailed Test

Journal: RSC Advances

Article Title: Anti-SARS-CoV-2 and cytotoxic activity of two marine alkaloids from green alga Caulerpa cylindracea Sonder in the Dardanelles †

doi: 10.1039/d2ra03358e

Figure Lengend Snippet: Spike and ACE2 binding activity of (a) caulerpin and (b) monomethyl caulerpinate at different concentrations.

Article Snippet: Antiviral activity was analyzed by using multimode microplate reader (HIDEX Sense) for SARS-CoV-2 assays (BPS Biosciences, MBP-tagged Assay Kit #79955-2, ACE2 Inhibitor Screening Assay Kit, #79931).

Techniques: Binding Assay, Activity Assay

Journal: RSC Advances

Article Title: Anti-SARS-CoV-2 and cytotoxic activity of two marine alkaloids from green alga Caulerpa cylindracea Sonder in the Dardanelles †

doi: 10.1039/d2ra03358e

Figure Lengend Snippet: The docked pose caulerpin (top) and monomethyl caulerpinate (middle) with the SARS-CoV-2 spike protein (pdb 6m0j ). The ligand interacts with the pocket on spike to which ACE2 also binds (bottom). Hydrogen bonds are indicated in yellow dashed (3D) or purple solid (2D plots) lines. π–π stackings are shown in blue dashed (3D) and green solid (2D plots) lines.

Article Snippet: Antiviral activity was analyzed by using multimode microplate reader (HIDEX Sense) for SARS-CoV-2 assays (BPS Biosciences, MBP-tagged Assay Kit #79955-2, ACE2 Inhibitor Screening Assay Kit, #79931).

Techniques:

Journal: RSC Advances

Article Title: Anti-SARS-CoV-2 and cytotoxic activity of two marine alkaloids from green alga Caulerpa cylindracea Sonder in the Dardanelles †

doi: 10.1039/d2ra03358e

Figure Lengend Snippet: The docked pose monomethyl caulerpinate with the SARS-CoV-2 spike protein (pdb 7l4z ). Hydrogen bonds are indicated in yellow dashed (3D) or purple solid (2D plots) lines. π–π stackings are shown in blue dashed (3D) and green solid (2D plots) lines.

Article Snippet: Antiviral activity was analyzed by using multimode microplate reader (HIDEX Sense) for SARS-CoV-2 assays (BPS Biosciences, MBP-tagged Assay Kit #79955-2, ACE2 Inhibitor Screening Assay Kit, #79931).

Techniques:

Journal: PLoS ONE

Article Title: Epigallocatechin gallate (EGCG) attenuates severe acute respiratory coronavirus disease 2 (SARS-CoV-2) infection by blocking the interaction of SARS-CoV-2 spike protein receptor-binding domain to human angiotensin-converting enzyme 2

doi: 10.1371/journal.pone.0271112

Figure Lengend Snippet: (A) Schematic of the ELISA-based screening of phytochemical inhibitory activity on ACE2 and SARS-CoV-2 spike RBD binding. Upper scheme: When the compound does not block the ACE2 and spike RBD binding. Lower scheme: When the compound blocks the ACE2 and spike RBD binding. (B) ELISA results of phytochemical inhibition of the ACE2 and spike RBD binding. Low-intensity HRP signals indicate that the compound successfully blocked the ACE2 and spike RBD binding. Values are presented as the mean ± SD. Asterisks indicate the significant difference compared with the DMSO-treated control (** p < 0.01, * p < 0.05). (C) ELISA results of serially diluted EGCG (3.125–100 μM) inhibition of ACE2 and spike RBD binding b. IC50 was calculated using the IC50 calculator ( https://www.aatbio.com/tools/ic50-calculator ).

Article Snippet: We examined the inhibitory effects of SARS-CoV-2 RBD and ACE2 binding by ELISAs using the Spike S1 RBD (SARS-CoV-2): ACE2 Inhibitor Screening Assay Kit (BPS Bioscience, #79931, San Diego, CA, USA) following the manufacturer’s instructions; we tested all compounds at 100 or 20 μM, and we briefly incubated SARS-CoV-2 spike RBD-Fc (50 ng) overnight for 12 h into a nickel-coated 96-well plate.

Techniques: Enzyme-linked Immunosorbent Assay, Activity Assay, Binding Assay, Blocking Assay, Inhibition

Journal: PLoS ONE

Article Title: Epigallocatechin gallate (EGCG) attenuates severe acute respiratory coronavirus disease 2 (SARS-CoV-2) infection by blocking the interaction of SARS-CoV-2 spike protein receptor-binding domain to human angiotensin-converting enzyme 2

doi: 10.1371/journal.pone.0271112

Figure Lengend Snippet: ( A ) Interacting residues determined within a 5-Å region at the interface of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain (RBD) and human ACE2 from their crystal structure (6M17). ( B & C ) Molecular docking of human ACE2 and EGCG. ( B ) Three-dimensional representation of EGCG binding with the human ACE2 peptidase domain (left) and magnified image (right). ( C ) Two-dimensional interaction analysis of ACE2 and EGCG, highlighting the ACE2 residues that interact with EGCG and the types and lengths of their bonds. Residues are color coded according to the type of interaction: dark green, conventional hydrogen bonds; light green, van der Waals forces; dark pink, Pi–Pi stacked interactions; and light pink, Pi–alkyl interactions.

Article Snippet: We examined the inhibitory effects of SARS-CoV-2 RBD and ACE2 binding by ELISAs using the Spike S1 RBD (SARS-CoV-2): ACE2 Inhibitor Screening Assay Kit (BPS Bioscience, #79931, San Diego, CA, USA) following the manufacturer’s instructions; we tested all compounds at 100 or 20 μM, and we briefly incubated SARS-CoV-2 spike RBD-Fc (50 ng) overnight for 12 h into a nickel-coated 96-well plate.

Techniques: Binding Assay

Journal: PLoS ONE

Article Title: Epigallocatechin gallate (EGCG) attenuates severe acute respiratory coronavirus disease 2 (SARS-CoV-2) infection by blocking the interaction of SARS-CoV-2 spike protein receptor-binding domain to human angiotensin-converting enzyme 2

doi: 10.1371/journal.pone.0271112

Figure Lengend Snippet: ( A ) Images of 293FT and Caco-2 cells grown on 100-mm plates taken under a phase-contrast microscope. Scale bar: 100 μm. ( B ) Cropped image of western blot performed with ACE2 and Glyceraldehyde 3-phosphate dehydrogenase antibodies. ( C ) Outline of the experimental procedure. Caco-2 cells were treated with or without EGCG for 2 h. After treatment, the cells were washed with PBS thrice, and fresh medium was added. After 22 h of incubation, cell growth was determined. ( D ) Effects of EGCG on Caco-2 cell growth. Cell growth was assessed by the cell proliferation assay and expressed as a percentage of dimethyl sulfoxide (DMSO)-treated control cells. Asterisks indicate the significant difference compared with the DMSO-treated control (** p < 0.01).

Article Snippet: We examined the inhibitory effects of SARS-CoV-2 RBD and ACE2 binding by ELISAs using the Spike S1 RBD (SARS-CoV-2): ACE2 Inhibitor Screening Assay Kit (BPS Bioscience, #79931, San Diego, CA, USA) following the manufacturer’s instructions; we tested all compounds at 100 or 20 μM, and we briefly incubated SARS-CoV-2 spike RBD-Fc (50 ng) overnight for 12 h into a nickel-coated 96-well plate.

Techniques: Microscopy, Western Blot, Incubation, Proliferation Assay