3cl protease Search Results


94
R&D Systems recombinant sars cov 2 3cl protease
Recombinant Sars Cov 2 3cl Protease, supplied by R&D Systems, used in various techniques. Bioz Stars score: 94/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pmc08402917-36-6-11?v=R%26D+Systems
Average 94 stars, based on 1 article reviews
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92
BPS Bioscience 3clpro sarscov 2 assay kits
3clpro Sarscov 2 Assay Kits, supplied by BPS Bioscience, used in various techniques. Bioz Stars score: 92/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/10__1021_slash_acsomega__5c10895-127-1-5?v=BPS+Bioscience
Average 92 stars, based on 1 article reviews
3clpro sarscov 2 assay kits - by Bioz Stars, 2026-08
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93
R&D Systems 3cl pro
X-ray crystal structures of SARS-CoV2 <t>3CL</t> pro complexed with (A) ensitrelvir (PDB: 7VU6 ), (B) nirmatrelvir (PDB: 7RFS ), (C) compound 1 (PDB: 9LVR) and (D) compound 4 (PDB: 9LVT), respectively. The inhibitors are shown as cyan sticks. The backbone of 3CL pro is shown as a white ribbon, the amino acids interacting to inhibitors are highlighted as gray sticks, and hydrogen bonds are indicated as yellow dashed lines. The structures of inhibitors are also depicted at the bottom.
3cl Pro, supplied by R&D Systems, used in various techniques. Bioz Stars score: 93/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pmc12557365-496-11-13?v=R%26D+Systems
Average 93 stars, based on 1 article reviews
3cl pro - by Bioz Stars, 2026-08
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95
BPS Bioscience 3cl protease assay kit
X-ray crystal structures of SARS-CoV2 <t>3CL</t> pro complexed with (A) ensitrelvir (PDB: 7VU6 ), (B) nirmatrelvir (PDB: 7RFS ), (C) compound 1 (PDB: 9LVR) and (D) compound 4 (PDB: 9LVT), respectively. The inhibitors are shown as cyan sticks. The backbone of 3CL pro is shown as a white ribbon, the amino acids interacting to inhibitors are highlighted as gray sticks, and hydrogen bonds are indicated as yellow dashed lines. The structures of inhibitors are also depicted at the bottom.
3cl Protease Assay Kit, supplied by BPS Bioscience, used in various techniques. Bioz Stars score: 95/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pm41633253-89-12-16?v=BPS+Bioscience
Average 95 stars, based on 1 article reviews
3cl protease assay kit - by Bioz Stars, 2026-08
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93
R&D Systems sars cov 2 3cl protease
X-ray crystal structures of SARS-CoV2 <t>3CL</t> pro complexed with (A) ensitrelvir (PDB: 7VU6 ), (B) nirmatrelvir (PDB: 7RFS ), (C) compound 1 (PDB: 9LVR) and (D) compound 4 (PDB: 9LVT), respectively. The inhibitors are shown as cyan sticks. The backbone of 3CL pro is shown as a white ribbon, the amino acids interacting to inhibitors are highlighted as gray sticks, and hydrogen bonds are indicated as yellow dashed lines. The structures of inhibitors are also depicted at the bottom.
Sars Cov 2 3cl Protease, supplied by R&D Systems, used in various techniques. Bioz Stars score: 93/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pmc12557365-502-0-3?v=R%26D+Systems
Average 93 stars, based on 1 article reviews
sars cov 2 3cl protease - by Bioz Stars, 2026-08
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92
Rockland Immunochemicals rabbit anti sars cov 3cl pro
Development of cell-based luciferase complementation reporters to detect inhibition of SARS-CoV-2 <t>3CL</t> pro activity. ( A ) Strategy for detection of 3CL pro inhibition using NanoBiT, a luciferase complementation reporter comprised of Large BiT (L) and Small BiT (S). When connected by a linker containing a 3CL pro cleavage site, 3CL pro cleavage should result in a loss of complementation and low luciferase activity. Conversely, 3CL pro inhibitors should prevent cleavage, resulting in high luciferase activity. ( B ) Lentiviral vectors that express 3CL pro and reporters. P2A, a self-cleaving peptide, was inserted between 3CL pro and reporters. Reporters consisted of GFP linked to L and S in various orders. L and S were separated by the SARS-CoV-2 nsp4-nsp5 cleavage site. LTR, long terminal repeat; P EF1α , EF1α promoter; IRES, internal ribosome entry site; puro, puromycin resistance gene; WPRE, woodchuck hepatitis virus post-transcriptional regulatory element. ( C ) Western blotting to examine reporter expression and cleavage. Lentiviral vectors expressing 3CL pro WT or C145A (a catalytically inactive mutant) were transfected into 293T cells, and DMSO (control) or the 3CL pro inhibitor GC376 (100 µM) was added. Cell lysates were collected 30 h post-transfection. 3CL pro was detected using anti-SARS-CoV 3CL pro or anti-P2A antibodies, whereas reporters were detected using anti-GFP or anti-L antibodies. Arrows denote cleavage products of expected sizes. For 3CL pro C145A, two different plasmid amounts were transfected: 2 or 0.4 µg. HSP90 was included as a loading control. ( D ) NanoBiT luciferase activity. 293T cells were transfected (same sample order as in C ), and NanoBiT activity (expressed as relative luciferase units, or RLU) was measured 30 h post-transfection. The data represent the mean ± standard deviation of four independent experiments; ns: not significant; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to 3CL pro WT without drug; mixed effects analysis with Dunnett’s post-test).
Rabbit Anti Sars Cov 3cl Pro, supplied by Rockland Immunochemicals, used in various techniques. Bioz Stars score: 92/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pmc07911889-111-10-14?v=Rockland+Immunochemicals
Average 92 stars, based on 1 article reviews
rabbit anti sars cov 3cl pro - by Bioz Stars, 2026-08
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93
R&D Systems mers cov
Development of cell-based luciferase complementation reporters to detect inhibition of SARS-CoV-2 <t>3CL</t> pro activity. ( A ) Strategy for detection of 3CL pro inhibition using NanoBiT, a luciferase complementation reporter comprised of Large BiT (L) and Small BiT (S). When connected by a linker containing a 3CL pro cleavage site, 3CL pro cleavage should result in a loss of complementation and low luciferase activity. Conversely, 3CL pro inhibitors should prevent cleavage, resulting in high luciferase activity. ( B ) Lentiviral vectors that express 3CL pro and reporters. P2A, a self-cleaving peptide, was inserted between 3CL pro and reporters. Reporters consisted of GFP linked to L and S in various orders. L and S were separated by the SARS-CoV-2 nsp4-nsp5 cleavage site. LTR, long terminal repeat; P EF1α , EF1α promoter; IRES, internal ribosome entry site; puro, puromycin resistance gene; WPRE, woodchuck hepatitis virus post-transcriptional regulatory element. ( C ) Western blotting to examine reporter expression and cleavage. Lentiviral vectors expressing 3CL pro WT or C145A (a catalytically inactive mutant) were transfected into 293T cells, and DMSO (control) or the 3CL pro inhibitor GC376 (100 µM) was added. Cell lysates were collected 30 h post-transfection. 3CL pro was detected using anti-SARS-CoV 3CL pro or anti-P2A antibodies, whereas reporters were detected using anti-GFP or anti-L antibodies. Arrows denote cleavage products of expected sizes. For 3CL pro C145A, two different plasmid amounts were transfected: 2 or 0.4 µg. HSP90 was included as a loading control. ( D ) NanoBiT luciferase activity. 293T cells were transfected (same sample order as in C ), and NanoBiT activity (expressed as relative luciferase units, or RLU) was measured 30 h post-transfection. The data represent the mean ± standard deviation of four independent experiments; ns: not significant; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to 3CL pro WT without drug; mixed effects analysis with Dunnett’s post-test).
Mers Cov, supplied by R&D Systems, used in various techniques. Bioz Stars score: 93/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pmc12624906-74-8-12?v=R%26D+Systems
Average 93 stars, based on 1 article reviews
mers cov - by Bioz Stars, 2026-08
93/100 stars
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93
BPS Bioscience catalog 100823
Development of cell-based luciferase complementation reporters to detect inhibition of SARS-CoV-2 <t>3CL</t> pro activity. ( A ) Strategy for detection of 3CL pro inhibition using NanoBiT, a luciferase complementation reporter comprised of Large BiT (L) and Small BiT (S). When connected by a linker containing a 3CL pro cleavage site, 3CL pro cleavage should result in a loss of complementation and low luciferase activity. Conversely, 3CL pro inhibitors should prevent cleavage, resulting in high luciferase activity. ( B ) Lentiviral vectors that express 3CL pro and reporters. P2A, a self-cleaving peptide, was inserted between 3CL pro and reporters. Reporters consisted of GFP linked to L and S in various orders. L and S were separated by the SARS-CoV-2 nsp4-nsp5 cleavage site. LTR, long terminal repeat; P EF1α , EF1α promoter; IRES, internal ribosome entry site; puro, puromycin resistance gene; WPRE, woodchuck hepatitis virus post-transcriptional regulatory element. ( C ) Western blotting to examine reporter expression and cleavage. Lentiviral vectors expressing 3CL pro WT or C145A (a catalytically inactive mutant) were transfected into 293T cells, and DMSO (control) or the 3CL pro inhibitor GC376 (100 µM) was added. Cell lysates were collected 30 h post-transfection. 3CL pro was detected using anti-SARS-CoV 3CL pro or anti-P2A antibodies, whereas reporters were detected using anti-GFP or anti-L antibodies. Arrows denote cleavage products of expected sizes. For 3CL pro C145A, two different plasmid amounts were transfected: 2 or 0.4 µg. HSP90 was included as a loading control. ( D ) NanoBiT luciferase activity. 293T cells were transfected (same sample order as in C ), and NanoBiT activity (expressed as relative luciferase units, or RLU) was measured 30 h post-transfection. The data represent the mean ± standard deviation of four independent experiments; ns: not significant; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to 3CL pro WT without drug; mixed effects analysis with Dunnett’s post-test).
Catalog 100823, supplied by BPS Bioscience, used in various techniques. Bioz Stars score: 93/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pmc12956004-206-17-14?v=BPS+Bioscience
Average 93 stars, based on 1 article reviews
catalog 100823 - by Bioz Stars, 2026-08
93/100 stars
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93
R&D Systems recombinant m pro enzymes
Development of cell-based luciferase complementation reporters to detect inhibition of SARS-CoV-2 <t>3CL</t> pro activity. ( A ) Strategy for detection of 3CL pro inhibition using NanoBiT, a luciferase complementation reporter comprised of Large BiT (L) and Small BiT (S). When connected by a linker containing a 3CL pro cleavage site, 3CL pro cleavage should result in a loss of complementation and low luciferase activity. Conversely, 3CL pro inhibitors should prevent cleavage, resulting in high luciferase activity. ( B ) Lentiviral vectors that express 3CL pro and reporters. P2A, a self-cleaving peptide, was inserted between 3CL pro and reporters. Reporters consisted of GFP linked to L and S in various orders. L and S were separated by the SARS-CoV-2 nsp4-nsp5 cleavage site. LTR, long terminal repeat; P EF1α , EF1α promoter; IRES, internal ribosome entry site; puro, puromycin resistance gene; WPRE, woodchuck hepatitis virus post-transcriptional regulatory element. ( C ) Western blotting to examine reporter expression and cleavage. Lentiviral vectors expressing 3CL pro WT or C145A (a catalytically inactive mutant) were transfected into 293T cells, and DMSO (control) or the 3CL pro inhibitor GC376 (100 µM) was added. Cell lysates were collected 30 h post-transfection. 3CL pro was detected using anti-SARS-CoV 3CL pro or anti-P2A antibodies, whereas reporters were detected using anti-GFP or anti-L antibodies. Arrows denote cleavage products of expected sizes. For 3CL pro C145A, two different plasmid amounts were transfected: 2 or 0.4 µg. HSP90 was included as a loading control. ( D ) NanoBiT luciferase activity. 293T cells were transfected (same sample order as in C ), and NanoBiT activity (expressed as relative luciferase units, or RLU) was measured 30 h post-transfection. The data represent the mean ± standard deviation of four independent experiments; ns: not significant; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to 3CL pro WT without drug; mixed effects analysis with Dunnett’s post-test).
Recombinant M Pro Enzymes, supplied by R&D Systems, used in various techniques. Bioz Stars score: 93/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pmc12624906-74-1-12?v=R%26D+Systems
Average 93 stars, based on 1 article reviews
recombinant m pro enzymes - by Bioz Stars, 2026-08
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93
R&D Systems sars cov 3cl protease
<t>SARS-CoV-2</t> <t>3CL</t> pro expression and characterization. (a) SDS-PAGE of 3CL pro ; the calculated molecular weight of the 3CL pro is 33,796 Da. (b) Michaelis-Menten plot of 15 nM 3CL pro with various concentrations of FRET substrate (c) Initial velocity plot of enzyme reaction with various concentrations of 3CL pro . (d) Principle of the enzymatic FRET-based assay used to monitor 3CL pro activity. Once the fluorogenic substrate is cleaved by the enzyme, the fluorophore (Edans) and the fluorescence quencher (Dabcyl) are spatially separated, resulting in an increase in fluorescence which is proportional to the enzyme activity. <t>(e)</t> <t>SARS-CoV-2</t> 3CL pro inhibition by reference compounds. 3CL pro was pre-incubated 30 min with various concentration of GC-376 or boceprevir before FRET substrate addition and initial velocity measurement. Data are shown as mean ± SD of duplicates from representative experiments.
Sars Cov 3cl Protease, supplied by R&D Systems, used in various techniques. Bioz Stars score: 93/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pmc09901219-208-0-6?v=R%26D+Systems
Average 93 stars, based on 1 article reviews
sars cov 3cl protease - by Bioz Stars, 2026-08
93/100 stars
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93
BPS Bioscience 3cl protease
<t>SARS-CoV-2</t> <t>3CL</t> pro expression and characterization. (a) SDS-PAGE of 3CL pro ; the calculated molecular weight of the 3CL pro is 33,796 Da. (b) Michaelis-Menten plot of 15 nM 3CL pro with various concentrations of FRET substrate (c) Initial velocity plot of enzyme reaction with various concentrations of 3CL pro . (d) Principle of the enzymatic FRET-based assay used to monitor 3CL pro activity. Once the fluorogenic substrate is cleaved by the enzyme, the fluorophore (Edans) and the fluorescence quencher (Dabcyl) are spatially separated, resulting in an increase in fluorescence which is proportional to the enzyme activity. <t>(e)</t> <t>SARS-CoV-2</t> 3CL pro inhibition by reference compounds. 3CL pro was pre-incubated 30 min with various concentration of GC-376 or boceprevir before FRET substrate addition and initial velocity measurement. Data are shown as mean ± SD of duplicates from representative experiments.
3cl Protease, supplied by BPS Bioscience, used in various techniques. Bioz Stars score: 93/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/3cl+protease/pm34585460-79-9-16?v=BPS+Bioscience
Average 93 stars, based on 1 article reviews
3cl protease - by Bioz Stars, 2026-08
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Image Search Results


X-ray crystal structures of SARS-CoV2 3CL pro complexed with (A) ensitrelvir (PDB: 7VU6 ), (B) nirmatrelvir (PDB: 7RFS ), (C) compound 1 (PDB: 9LVR) and (D) compound 4 (PDB: 9LVT), respectively. The inhibitors are shown as cyan sticks. The backbone of 3CL pro is shown as a white ribbon, the amino acids interacting to inhibitors are highlighted as gray sticks, and hydrogen bonds are indicated as yellow dashed lines. The structures of inhibitors are also depicted at the bottom.

Journal: Journal of Medicinal Chemistry

Article Title: Discovery of the Clinical Candidate S‑892216 : A Second-Generation of SARS-CoV‑2 3CL Protease Inhibitor for Treating COVID-19

doi: 10.1021/acs.jmedchem.5c00754

Figure Lengend Snippet: X-ray crystal structures of SARS-CoV2 3CL pro complexed with (A) ensitrelvir (PDB: 7VU6 ), (B) nirmatrelvir (PDB: 7RFS ), (C) compound 1 (PDB: 9LVR) and (D) compound 4 (PDB: 9LVT), respectively. The inhibitors are shown as cyan sticks. The backbone of 3CL pro is shown as a white ribbon, the amino acids interacting to inhibitors are highlighted as gray sticks, and hydrogen bonds are indicated as yellow dashed lines. The structures of inhibitors are also depicted at the bottom.

Article Snippet: The reaction was initiated by adding 5 or 7.5 μL of 3CL pro (R&D Systems, Inc.) in assay buffer and incubated at room temperature for 4 to 5 h. The final concentration of enzyme was 0.3 nM in reaction mixture.

Techniques:

X-ray crystal structure of S-892216 complexed with SARS-CoV-2 3CL pro (PDB: 9LVV). S-892216 is shown as a cyan stick, and the protein backbone is shown as a gray ribbon. Residues interacting with S-892216 are indicated as gray and orange sticks. Hydrogen bonds are indicated as yellow dashed lines, and π–π stacking is indicated as a cyan dashed line.

Journal: Journal of Medicinal Chemistry

Article Title: Discovery of the Clinical Candidate S‑892216 : A Second-Generation of SARS-CoV‑2 3CL Protease Inhibitor for Treating COVID-19

doi: 10.1021/acs.jmedchem.5c00754

Figure Lengend Snippet: X-ray crystal structure of S-892216 complexed with SARS-CoV-2 3CL pro (PDB: 9LVV). S-892216 is shown as a cyan stick, and the protein backbone is shown as a gray ribbon. Residues interacting with S-892216 are indicated as gray and orange sticks. Hydrogen bonds are indicated as yellow dashed lines, and π–π stacking is indicated as a cyan dashed line.

Article Snippet: The reaction was initiated by adding 5 or 7.5 μL of 3CL pro (R&D Systems, Inc.) in assay buffer and incubated at room temperature for 4 to 5 h. The final concentration of enzyme was 0.3 nM in reaction mixture.

Techniques:

Dissociation kinetics of S-892216 from 3CL pro measured using a SPA-based assay. (A) Schematic illustration of S-892216 dissociation kinetics study. Sample 1: [ 14 C]- S-892216 alone; Sample 2: excess amount of nonlabeled S-892216 was added immediately before measurement; Sample 3 excess amount of nonlabeled S-892216 was added before preincubation. [ 14 C]- S-892216 : red circle, Nonlabeled S-892216 : blue circle, buffer: white circle. (B) Dissociation kinetics of [ 14 C]- S-892216 was monitored using scintillation signals. Data fitted in GraphPad Prism 9 using one-phase exponential decay.

Journal: Journal of Medicinal Chemistry

Article Title: Discovery of the Clinical Candidate S‑892216 : A Second-Generation of SARS-CoV‑2 3CL Protease Inhibitor for Treating COVID-19

doi: 10.1021/acs.jmedchem.5c00754

Figure Lengend Snippet: Dissociation kinetics of S-892216 from 3CL pro measured using a SPA-based assay. (A) Schematic illustration of S-892216 dissociation kinetics study. Sample 1: [ 14 C]- S-892216 alone; Sample 2: excess amount of nonlabeled S-892216 was added immediately before measurement; Sample 3 excess amount of nonlabeled S-892216 was added before preincubation. [ 14 C]- S-892216 : red circle, Nonlabeled S-892216 : blue circle, buffer: white circle. (B) Dissociation kinetics of [ 14 C]- S-892216 was monitored using scintillation signals. Data fitted in GraphPad Prism 9 using one-phase exponential decay.

Article Snippet: The reaction was initiated by adding 5 or 7.5 μL of 3CL pro (R&D Systems, Inc.) in assay buffer and incubated at room temperature for 4 to 5 h. The final concentration of enzyme was 0.3 nM in reaction mixture.

Techniques:

X-ray crystal structures of SARS-CoV2 3CL pro complexed with (A) ensitrelvir (PDB: 7VU6 ), (B) nirmatrelvir (PDB: 7RFS ), (C) compound 1 (PDB: 9LVR) and (D) compound 4 (PDB: 9LVT), respectively. The inhibitors are shown as cyan sticks. The backbone of 3CL pro is shown as a white ribbon, the amino acids interacting to inhibitors are highlighted as gray sticks, and hydrogen bonds are indicated as yellow dashed lines. The structures of inhibitors are also depicted at the bottom.

Journal: Journal of Medicinal Chemistry

Article Title: Discovery of the Clinical Candidate S‑892216 : A Second-Generation of SARS-CoV‑2 3CL Protease Inhibitor for Treating COVID-19

doi: 10.1021/acs.jmedchem.5c00754

Figure Lengend Snippet: X-ray crystal structures of SARS-CoV2 3CL pro complexed with (A) ensitrelvir (PDB: 7VU6 ), (B) nirmatrelvir (PDB: 7RFS ), (C) compound 1 (PDB: 9LVR) and (D) compound 4 (PDB: 9LVT), respectively. The inhibitors are shown as cyan sticks. The backbone of 3CL pro is shown as a white ribbon, the amino acids interacting to inhibitors are highlighted as gray sticks, and hydrogen bonds are indicated as yellow dashed lines. The structures of inhibitors are also depicted at the bottom.

Article Snippet: SARS-CoV-2 3CL protease (R&D systems) were attached to SPA beads by incubating 0.27 μM random biotinylated-SARS-CoV-2 3CL protease and 7 mg/mL streptavidin YSi SPA scintillation beads (Revvity) in assay buffer (10 mM Tris pH7.5, 5 mM DTT, 0.5 mM EDTA, 0.005% Tween20).

Techniques:

X-ray crystal structure of S-892216 complexed with SARS-CoV-2 3CL pro (PDB: 9LVV). S-892216 is shown as a cyan stick, and the protein backbone is shown as a gray ribbon. Residues interacting with S-892216 are indicated as gray and orange sticks. Hydrogen bonds are indicated as yellow dashed lines, and π–π stacking is indicated as a cyan dashed line.

Journal: Journal of Medicinal Chemistry

Article Title: Discovery of the Clinical Candidate S‑892216 : A Second-Generation of SARS-CoV‑2 3CL Protease Inhibitor for Treating COVID-19

doi: 10.1021/acs.jmedchem.5c00754

Figure Lengend Snippet: X-ray crystal structure of S-892216 complexed with SARS-CoV-2 3CL pro (PDB: 9LVV). S-892216 is shown as a cyan stick, and the protein backbone is shown as a gray ribbon. Residues interacting with S-892216 are indicated as gray and orange sticks. Hydrogen bonds are indicated as yellow dashed lines, and π–π stacking is indicated as a cyan dashed line.

Article Snippet: SARS-CoV-2 3CL protease (R&D systems) were attached to SPA beads by incubating 0.27 μM random biotinylated-SARS-CoV-2 3CL protease and 7 mg/mL streptavidin YSi SPA scintillation beads (Revvity) in assay buffer (10 mM Tris pH7.5, 5 mM DTT, 0.5 mM EDTA, 0.005% Tween20).

Techniques:

Dissociation kinetics of S-892216 from 3CL pro measured using a SPA-based assay. (A) Schematic illustration of S-892216 dissociation kinetics study. Sample 1: [ 14 C]- S-892216 alone; Sample 2: excess amount of nonlabeled S-892216 was added immediately before measurement; Sample 3 excess amount of nonlabeled S-892216 was added before preincubation. [ 14 C]- S-892216 : red circle, Nonlabeled S-892216 : blue circle, buffer: white circle. (B) Dissociation kinetics of [ 14 C]- S-892216 was monitored using scintillation signals. Data fitted in GraphPad Prism 9 using one-phase exponential decay.

Journal: Journal of Medicinal Chemistry

Article Title: Discovery of the Clinical Candidate S‑892216 : A Second-Generation of SARS-CoV‑2 3CL Protease Inhibitor for Treating COVID-19

doi: 10.1021/acs.jmedchem.5c00754

Figure Lengend Snippet: Dissociation kinetics of S-892216 from 3CL pro measured using a SPA-based assay. (A) Schematic illustration of S-892216 dissociation kinetics study. Sample 1: [ 14 C]- S-892216 alone; Sample 2: excess amount of nonlabeled S-892216 was added immediately before measurement; Sample 3 excess amount of nonlabeled S-892216 was added before preincubation. [ 14 C]- S-892216 : red circle, Nonlabeled S-892216 : blue circle, buffer: white circle. (B) Dissociation kinetics of [ 14 C]- S-892216 was monitored using scintillation signals. Data fitted in GraphPad Prism 9 using one-phase exponential decay.

Article Snippet: SARS-CoV-2 3CL protease (R&D systems) were attached to SPA beads by incubating 0.27 μM random biotinylated-SARS-CoV-2 3CL protease and 7 mg/mL streptavidin YSi SPA scintillation beads (Revvity) in assay buffer (10 mM Tris pH7.5, 5 mM DTT, 0.5 mM EDTA, 0.005% Tween20).

Techniques:

Development of cell-based luciferase complementation reporters to detect inhibition of SARS-CoV-2 3CL pro activity. ( A ) Strategy for detection of 3CL pro inhibition using NanoBiT, a luciferase complementation reporter comprised of Large BiT (L) and Small BiT (S). When connected by a linker containing a 3CL pro cleavage site, 3CL pro cleavage should result in a loss of complementation and low luciferase activity. Conversely, 3CL pro inhibitors should prevent cleavage, resulting in high luciferase activity. ( B ) Lentiviral vectors that express 3CL pro and reporters. P2A, a self-cleaving peptide, was inserted between 3CL pro and reporters. Reporters consisted of GFP linked to L and S in various orders. L and S were separated by the SARS-CoV-2 nsp4-nsp5 cleavage site. LTR, long terminal repeat; P EF1α , EF1α promoter; IRES, internal ribosome entry site; puro, puromycin resistance gene; WPRE, woodchuck hepatitis virus post-transcriptional regulatory element. ( C ) Western blotting to examine reporter expression and cleavage. Lentiviral vectors expressing 3CL pro WT or C145A (a catalytically inactive mutant) were transfected into 293T cells, and DMSO (control) or the 3CL pro inhibitor GC376 (100 µM) was added. Cell lysates were collected 30 h post-transfection. 3CL pro was detected using anti-SARS-CoV 3CL pro or anti-P2A antibodies, whereas reporters were detected using anti-GFP or anti-L antibodies. Arrows denote cleavage products of expected sizes. For 3CL pro C145A, two different plasmid amounts were transfected: 2 or 0.4 µg. HSP90 was included as a loading control. ( D ) NanoBiT luciferase activity. 293T cells were transfected (same sample order as in C ), and NanoBiT activity (expressed as relative luciferase units, or RLU) was measured 30 h post-transfection. The data represent the mean ± standard deviation of four independent experiments; ns: not significant; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to 3CL pro WT without drug; mixed effects analysis with Dunnett’s post-test).

Journal: Viruses

Article Title: Development of a Cell-Based Luciferase Complementation Assay for Identification of SARS-CoV-2 3CL pro Inhibitors

doi: 10.3390/v13020173

Figure Lengend Snippet: Development of cell-based luciferase complementation reporters to detect inhibition of SARS-CoV-2 3CL pro activity. ( A ) Strategy for detection of 3CL pro inhibition using NanoBiT, a luciferase complementation reporter comprised of Large BiT (L) and Small BiT (S). When connected by a linker containing a 3CL pro cleavage site, 3CL pro cleavage should result in a loss of complementation and low luciferase activity. Conversely, 3CL pro inhibitors should prevent cleavage, resulting in high luciferase activity. ( B ) Lentiviral vectors that express 3CL pro and reporters. P2A, a self-cleaving peptide, was inserted between 3CL pro and reporters. Reporters consisted of GFP linked to L and S in various orders. L and S were separated by the SARS-CoV-2 nsp4-nsp5 cleavage site. LTR, long terminal repeat; P EF1α , EF1α promoter; IRES, internal ribosome entry site; puro, puromycin resistance gene; WPRE, woodchuck hepatitis virus post-transcriptional regulatory element. ( C ) Western blotting to examine reporter expression and cleavage. Lentiviral vectors expressing 3CL pro WT or C145A (a catalytically inactive mutant) were transfected into 293T cells, and DMSO (control) or the 3CL pro inhibitor GC376 (100 µM) was added. Cell lysates were collected 30 h post-transfection. 3CL pro was detected using anti-SARS-CoV 3CL pro or anti-P2A antibodies, whereas reporters were detected using anti-GFP or anti-L antibodies. Arrows denote cleavage products of expected sizes. For 3CL pro C145A, two different plasmid amounts were transfected: 2 or 0.4 µg. HSP90 was included as a loading control. ( D ) NanoBiT luciferase activity. 293T cells were transfected (same sample order as in C ), and NanoBiT activity (expressed as relative luciferase units, or RLU) was measured 30 h post-transfection. The data represent the mean ± standard deviation of four independent experiments; ns: not significant; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to 3CL pro WT without drug; mixed effects analysis with Dunnett’s post-test).

Article Snippet: After transfer to PVDF membranes, blots were probed with 1:5000 rabbit anti-SARS-CoV 3CL pro (Rockland Immunochemicals; Limerick, PA, USA; catalog #200-401-A51), mouse anti-P2A (Novus Biologicals; Littleton, CO, USA; catalog #NBP2-59627), mouse anti-L (Promega; catalog #N710A), or rabbit anti-GFP antibodies (Invitrogen; Carlsbad, CA, USA; catalog #A6455).

Techniques: Luciferase, Inhibition, Activity Assay, Virus, Western Blot, Expressing, Mutagenesis, Transfection, Control, Plasmid Preparation, Standard Deviation

The luciferase complementation assay accurately reflects concentration-dependent inhibition of SARS-CoV-2 3CL pro -mediated cleavage. ( A ) Western blotting to examine reporter cleavage. 293T cells were transfected with the lentiviral vector containing 3CL pro WT and the S-L-GFP reporter cassette, and DMSO (control) or GC376 (0.1, 0.4, 1.6, 6.3, 25, 100, or 200 µM) was added. Mock transfection (MT) and 3CL pro C145A S-L-GFP were included as controls. On the GFP and LgBiT (L) panels, the bottom band corresponds to cleaved reporter (L-GFP, 46 kDa, indicated by arrows), while the top band corresponds to uncleaved reporter (S-L-GFP, 49 kDa). ( B ) Quantification of the percentage of uncleaved reporter from three independent western blots based on GFP (circle) or L (triangle) detection. ( C ) NanoBiT luciferase activity and cell viability. 293T cells were transfected with the S-L-GFP lentiviral vector, and DMSO (control) or GC376 (0.1, 0.4, 1.6, 6.3, 25, or 100 µM) was added. NanoBiT activity (circle, left axis) and cell viability (measured with the CellTiter-Glo 2.0 assay; triangle, right axis) were analyzed 30 h post-transfection and are expressed as relative luciferase units (RLU). Cell viability data were normalized to the DMSO sample, which was set to 100%. NanoBiT data were normalized to the DMSO and 100 µM GC376 samples, which were set to 0 and 100%, respectively. The data represent the mean ± standard deviation of four independent experiments; ns: not significant; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to no-drug; one-way ANOVA with Dunnett’s post-test).

Journal: Viruses

Article Title: Development of a Cell-Based Luciferase Complementation Assay for Identification of SARS-CoV-2 3CL pro Inhibitors

doi: 10.3390/v13020173

Figure Lengend Snippet: The luciferase complementation assay accurately reflects concentration-dependent inhibition of SARS-CoV-2 3CL pro -mediated cleavage. ( A ) Western blotting to examine reporter cleavage. 293T cells were transfected with the lentiviral vector containing 3CL pro WT and the S-L-GFP reporter cassette, and DMSO (control) or GC376 (0.1, 0.4, 1.6, 6.3, 25, 100, or 200 µM) was added. Mock transfection (MT) and 3CL pro C145A S-L-GFP were included as controls. On the GFP and LgBiT (L) panels, the bottom band corresponds to cleaved reporter (L-GFP, 46 kDa, indicated by arrows), while the top band corresponds to uncleaved reporter (S-L-GFP, 49 kDa). ( B ) Quantification of the percentage of uncleaved reporter from three independent western blots based on GFP (circle) or L (triangle) detection. ( C ) NanoBiT luciferase activity and cell viability. 293T cells were transfected with the S-L-GFP lentiviral vector, and DMSO (control) or GC376 (0.1, 0.4, 1.6, 6.3, 25, or 100 µM) was added. NanoBiT activity (circle, left axis) and cell viability (measured with the CellTiter-Glo 2.0 assay; triangle, right axis) were analyzed 30 h post-transfection and are expressed as relative luciferase units (RLU). Cell viability data were normalized to the DMSO sample, which was set to 100%. NanoBiT data were normalized to the DMSO and 100 µM GC376 samples, which were set to 0 and 100%, respectively. The data represent the mean ± standard deviation of four independent experiments; ns: not significant; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to no-drug; one-way ANOVA with Dunnett’s post-test).

Article Snippet: After transfer to PVDF membranes, blots were probed with 1:5000 rabbit anti-SARS-CoV 3CL pro (Rockland Immunochemicals; Limerick, PA, USA; catalog #200-401-A51), mouse anti-P2A (Novus Biologicals; Littleton, CO, USA; catalog #NBP2-59627), mouse anti-L (Promega; catalog #N710A), or rabbit anti-GFP antibodies (Invitrogen; Carlsbad, CA, USA; catalog #A6455).

Techniques: Luciferase, Concentration Assay, Inhibition, Western Blot, Transfection, Plasmid Preparation, Control, Activity Assay, Standard Deviation

The luciferase complementation assay can easily distinguish 3CL pro inhibition from cytotoxicity. To determine if the luciferase complementation reporter assay can differentiate 3CL pro inhibition from cytotoxicity, 293T cells were transfected with the S-L-GFP lentiviral vector, and DMSO (control) or the anti-cancer drug doxorubicin (0.1–100 µM) was added. NanoBiT activity (circle, left axis) and cell viability (measured with the CellTiter-Glo 2.0 assay; triangle, right axis) were analyzed 30 h post-transfection and are expressed as relative luciferase units (RLU). Cell viability data were normalized to the DMSO sample, which was set to 100%. NanoBiT data were normalized to the DMSO and 100 µM GC376 samples, which were set to 0 and 100%, respectively. The data represent the mean ± standard deviation of three independent experiments.

Journal: Viruses

Article Title: Development of a Cell-Based Luciferase Complementation Assay for Identification of SARS-CoV-2 3CL pro Inhibitors

doi: 10.3390/v13020173

Figure Lengend Snippet: The luciferase complementation assay can easily distinguish 3CL pro inhibition from cytotoxicity. To determine if the luciferase complementation reporter assay can differentiate 3CL pro inhibition from cytotoxicity, 293T cells were transfected with the S-L-GFP lentiviral vector, and DMSO (control) or the anti-cancer drug doxorubicin (0.1–100 µM) was added. NanoBiT activity (circle, left axis) and cell viability (measured with the CellTiter-Glo 2.0 assay; triangle, right axis) were analyzed 30 h post-transfection and are expressed as relative luciferase units (RLU). Cell viability data were normalized to the DMSO sample, which was set to 100%. NanoBiT data were normalized to the DMSO and 100 µM GC376 samples, which were set to 0 and 100%, respectively. The data represent the mean ± standard deviation of three independent experiments.

Article Snippet: After transfer to PVDF membranes, blots were probed with 1:5000 rabbit anti-SARS-CoV 3CL pro (Rockland Immunochemicals; Limerick, PA, USA; catalog #200-401-A51), mouse anti-P2A (Novus Biologicals; Littleton, CO, USA; catalog #NBP2-59627), mouse anti-L (Promega; catalog #N710A), or rabbit anti-GFP antibodies (Invitrogen; Carlsbad, CA, USA; catalog #A6455).

Techniques: Luciferase, Inhibition, Reporter Assay, Transfection, Plasmid Preparation, Control, Activity Assay, Standard Deviation

HIV protease inhibitors do not block SARS-CoV-2 3CL pro activity in a cell-based luciferase complementation assay. To determine if HIV protease inhibitors are active against SARS-CoV-2 3CL pro in cells, 293T cells were transfected with the S-L-GFP lentiviral vector, and DMSO (control) or inhibitors (0.1, 0.4, 1.6, 6.3, 25, or 100 µM) were added. NanoBiT activity (circle, left axis) and cell viability (measured with the CellTiter-Glo 2.0 assay; triangle, right axis) were analyzed 30 h post-transfection and are expressed as relative luciferase units (RLU). Cell viability data were normalized to the DMSO sample, which was set to 100%. NanoBiT data were normalized to the DMSO and 100 µM GC376 samples, which were set to 0 and 100%, respectively. The data represent the mean ± standard deviation of three independent experiments; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to no-drug; one-way ANOVA with Dunnett’s post-test).

Journal: Viruses

Article Title: Development of a Cell-Based Luciferase Complementation Assay for Identification of SARS-CoV-2 3CL pro Inhibitors

doi: 10.3390/v13020173

Figure Lengend Snippet: HIV protease inhibitors do not block SARS-CoV-2 3CL pro activity in a cell-based luciferase complementation assay. To determine if HIV protease inhibitors are active against SARS-CoV-2 3CL pro in cells, 293T cells were transfected with the S-L-GFP lentiviral vector, and DMSO (control) or inhibitors (0.1, 0.4, 1.6, 6.3, 25, or 100 µM) were added. NanoBiT activity (circle, left axis) and cell viability (measured with the CellTiter-Glo 2.0 assay; triangle, right axis) were analyzed 30 h post-transfection and are expressed as relative luciferase units (RLU). Cell viability data were normalized to the DMSO sample, which was set to 100%. NanoBiT data were normalized to the DMSO and 100 µM GC376 samples, which were set to 0 and 100%, respectively. The data represent the mean ± standard deviation of three independent experiments; * p < 0.05, ** p < 0.01, *** p < 0.001 (relative to no-drug; one-way ANOVA with Dunnett’s post-test).

Article Snippet: After transfer to PVDF membranes, blots were probed with 1:5000 rabbit anti-SARS-CoV 3CL pro (Rockland Immunochemicals; Limerick, PA, USA; catalog #200-401-A51), mouse anti-P2A (Novus Biologicals; Littleton, CO, USA; catalog #NBP2-59627), mouse anti-L (Promega; catalog #N710A), or rabbit anti-GFP antibodies (Invitrogen; Carlsbad, CA, USA; catalog #A6455).

Techniques: Blocking Assay, Activity Assay, Luciferase, Transfection, Plasmid Preparation, Control, Standard Deviation

Compounds screened for inhibition of SARS-CoV-2  3CL  pro in cells.

Journal: Viruses

Article Title: Development of a Cell-Based Luciferase Complementation Assay for Identification of SARS-CoV-2 3CL pro Inhibitors

doi: 10.3390/v13020173

Figure Lengend Snippet: Compounds screened for inhibition of SARS-CoV-2 3CL pro in cells.

Article Snippet: After transfer to PVDF membranes, blots were probed with 1:5000 rabbit anti-SARS-CoV 3CL pro (Rockland Immunochemicals; Limerick, PA, USA; catalog #200-401-A51), mouse anti-P2A (Novus Biologicals; Littleton, CO, USA; catalog #NBP2-59627), mouse anti-L (Promega; catalog #N710A), or rabbit anti-GFP antibodies (Invitrogen; Carlsbad, CA, USA; catalog #A6455).

Techniques: Inhibition

Boceprevir, Z-FA-FMK, calpain inhibitor XII, and GRL-0496, inhibit SARS-CoV-2 3CL pro in a cell-based luciferase complementation assay. To determine if other compounds are active against SARS-CoV-2 3CL pro in cells, 293T cells were transfected with the S-L-GFP lentiviral vector, and DMSO (control) or compounds (0.1, 0.4, 1.6, 6.3, 25, or 100 µM) were added. NanoBiT activity (circle, left axis) and cell viability (measured with the CellTiter-Glo 2.0 assay; triangle, right axis) were analyzed 30 h post-transfection and are expressed as relative luciferase units (RLU). Cell viability data were normalized to the DMSO sample, which was set to 100%. NanoBiT data were normalized to the DMSO and 100 µM GC376 samples, which were set to 0 and 100%, respectively. The data represent the mean ± standard deviation of three independent experiments; ** p < 0.01, *** p < 0.001 (relative to no-drug; one-way ANOVA with Dunnett’s post-test).

Journal: Viruses

Article Title: Development of a Cell-Based Luciferase Complementation Assay for Identification of SARS-CoV-2 3CL pro Inhibitors

doi: 10.3390/v13020173

Figure Lengend Snippet: Boceprevir, Z-FA-FMK, calpain inhibitor XII, and GRL-0496, inhibit SARS-CoV-2 3CL pro in a cell-based luciferase complementation assay. To determine if other compounds are active against SARS-CoV-2 3CL pro in cells, 293T cells were transfected with the S-L-GFP lentiviral vector, and DMSO (control) or compounds (0.1, 0.4, 1.6, 6.3, 25, or 100 µM) were added. NanoBiT activity (circle, left axis) and cell viability (measured with the CellTiter-Glo 2.0 assay; triangle, right axis) were analyzed 30 h post-transfection and are expressed as relative luciferase units (RLU). Cell viability data were normalized to the DMSO sample, which was set to 100%. NanoBiT data were normalized to the DMSO and 100 µM GC376 samples, which were set to 0 and 100%, respectively. The data represent the mean ± standard deviation of three independent experiments; ** p < 0.01, *** p < 0.001 (relative to no-drug; one-way ANOVA with Dunnett’s post-test).

Article Snippet: After transfer to PVDF membranes, blots were probed with 1:5000 rabbit anti-SARS-CoV 3CL pro (Rockland Immunochemicals; Limerick, PA, USA; catalog #200-401-A51), mouse anti-P2A (Novus Biologicals; Littleton, CO, USA; catalog #NBP2-59627), mouse anti-L (Promega; catalog #N710A), or rabbit anti-GFP antibodies (Invitrogen; Carlsbad, CA, USA; catalog #A6455).

Techniques: Luciferase, Transfection, Plasmid Preparation, Control, Activity Assay, Standard Deviation

SARS-CoV-2 3CL pro expression and characterization. (a) SDS-PAGE of 3CL pro ; the calculated molecular weight of the 3CL pro is 33,796 Da. (b) Michaelis-Menten plot of 15 nM 3CL pro with various concentrations of FRET substrate (c) Initial velocity plot of enzyme reaction with various concentrations of 3CL pro . (d) Principle of the enzymatic FRET-based assay used to monitor 3CL pro activity. Once the fluorogenic substrate is cleaved by the enzyme, the fluorophore (Edans) and the fluorescence quencher (Dabcyl) are spatially separated, resulting in an increase in fluorescence which is proportional to the enzyme activity. (e) SARS-CoV-2 3CL pro inhibition by reference compounds. 3CL pro was pre-incubated 30 min with various concentration of GC-376 or boceprevir before FRET substrate addition and initial velocity measurement. Data are shown as mean ± SD of duplicates from representative experiments.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: SARS-CoV-2 3CL pro expression and characterization. (a) SDS-PAGE of 3CL pro ; the calculated molecular weight of the 3CL pro is 33,796 Da. (b) Michaelis-Menten plot of 15 nM 3CL pro with various concentrations of FRET substrate (c) Initial velocity plot of enzyme reaction with various concentrations of 3CL pro . (d) Principle of the enzymatic FRET-based assay used to monitor 3CL pro activity. Once the fluorogenic substrate is cleaved by the enzyme, the fluorophore (Edans) and the fluorescence quencher (Dabcyl) are spatially separated, resulting in an increase in fluorescence which is proportional to the enzyme activity. (e) SARS-CoV-2 3CL pro inhibition by reference compounds. 3CL pro was pre-incubated 30 min with various concentration of GC-376 or boceprevir before FRET substrate addition and initial velocity measurement. Data are shown as mean ± SD of duplicates from representative experiments.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Expressing, SDS Page, Molecular Weight, Activity Assay, Fluorescence, Inhibition, Incubation, Concentration Assay

Left. Overview of the screening. SARS-CoV-2 3CL pro inhibition was reported (%) for each incubate. Green dots: tested compounds at 30 μM, Red dots: positive controls (incubations with vehicle), Blue dots: negative controls (incubations w/o enzyme), Orange dots: reference compound Boceprevir at 40 μM, Light orange dots: Boceprevir at 4 μM. Right. Workflow of the screening campaign.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: Left. Overview of the screening. SARS-CoV-2 3CL pro inhibition was reported (%) for each incubate. Green dots: tested compounds at 30 μM, Red dots: positive controls (incubations with vehicle), Blue dots: negative controls (incubations w/o enzyme), Orange dots: reference compound Boceprevir at 40 μM, Light orange dots: Boceprevir at 4 μM. Right. Workflow of the screening campaign.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Inhibition

(a) SARS-CoV-2 3CL pro inhibition by hit compounds 1 . 3CL pro was pre-incubated 60 min or not with various concentration of compound before FRET substrate addition and initial velocity measurement. Inhibitions (%) are shown as duplicate from a representative experiment. (b) SARS-CoV-2 3CL pro inhibition by hit compounds in buffer containing (2 mM) or not GSH and THP. 3CL pro was pre-incubated 60 min with various concentration of compound before FRET substrate addition and initial velocity measurement. Inhibitions (%) are shown as duplicate from a representative experiment.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: (a) SARS-CoV-2 3CL pro inhibition by hit compounds 1 . 3CL pro was pre-incubated 60 min or not with various concentration of compound before FRET substrate addition and initial velocity measurement. Inhibitions (%) are shown as duplicate from a representative experiment. (b) SARS-CoV-2 3CL pro inhibition by hit compounds in buffer containing (2 mM) or not GSH and THP. 3CL pro was pre-incubated 60 min with various concentration of compound before FRET substrate addition and initial velocity measurement. Inhibitions (%) are shown as duplicate from a representative experiment.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Inhibition, Incubation, Concentration Assay

Assessment of the irreversible/reversible mechanism of inhibition with compound 1 . SARS-CoV-2 3CL pro was incubated with compound 1 in a jump dilution assay. Initial rates are measured just after the compound dilution with substrate and enzymatic inhibitions (%) are calculated as mean ± SD of triplicate. Data are representative of three other experiments.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: Assessment of the irreversible/reversible mechanism of inhibition with compound 1 . SARS-CoV-2 3CL pro was incubated with compound 1 in a jump dilution assay. Initial rates are measured just after the compound dilution with substrate and enzymatic inhibitions (%) are calculated as mean ± SD of triplicate. Data are representative of three other experiments.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Inhibition, Incubation, Dilution Assay

Evaluation of thermal stabilization of SARS-CoV-2 3CL pro by Thermal Shift Assay (TSA) in presence of Boceprevir, GC-376 or Cpd 1 (40 μM). Thermal shift (ΔTm) was calculated by subtracting reference melting temperature of the protease from the Tm in presence of the compound. Values presented are the means of ΔTm ± SD of the eight independent TSA experiments.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: Evaluation of thermal stabilization of SARS-CoV-2 3CL pro by Thermal Shift Assay (TSA) in presence of Boceprevir, GC-376 or Cpd 1 (40 μM). Thermal shift (ΔTm) was calculated by subtracting reference melting temperature of the protease from the Tm in presence of the compound. Values presented are the means of ΔTm ± SD of the eight independent TSA experiments.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Thermal Shift Assay

Interaction of SARS-CoV-2 3CL pro with compound 1 assessed by NMR spectroscopy. a) The variations in NMR resonance intensities (top) and chemical shift perturbations (CSP) (bottom) induced upon cpd 1 addition are displayed along the main protease sequence. b) The CSPs, shown in (a, bottom), have been color coded (from light yellow to red) and are displayed on the structure of the dimeric 3CL pro , with the two protomers shown in dark grey and white, respectively. The side chains of both catalytic His41 and Cys145 are shown in green. c) Overlaid 2D 1 H, 15 N-TROSY-HSQC spectra acquired on 2 H, 15 N-labelled 3CL pro (100 μM) in the absence (in blue) or in the presence (in red) of cpd 1 (target concentration of 2 mM). The final DMSO‑ d 6 concentration was 3%. The spectra were acquired at 305 K on a 900 MHz NMR spectrometer.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: Interaction of SARS-CoV-2 3CL pro with compound 1 assessed by NMR spectroscopy. a) The variations in NMR resonance intensities (top) and chemical shift perturbations (CSP) (bottom) induced upon cpd 1 addition are displayed along the main protease sequence. b) The CSPs, shown in (a, bottom), have been color coded (from light yellow to red) and are displayed on the structure of the dimeric 3CL pro , with the two protomers shown in dark grey and white, respectively. The side chains of both catalytic His41 and Cys145 are shown in green. c) Overlaid 2D 1 H, 15 N-TROSY-HSQC spectra acquired on 2 H, 15 N-labelled 3CL pro (100 μM) in the absence (in blue) or in the presence (in red) of cpd 1 (target concentration of 2 mM). The final DMSO‑ d 6 concentration was 3%. The spectra were acquired at 305 K on a 900 MHz NMR spectrometer.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Spectroscopy, Sequencing, Concentration Assay

Crystallographic structure of the SARS-CoV-2 3CL pro bound to the N-(pyridin-3-ylmethyl)thioformamide moiety (in pink) from the compound 1 (PDB ID: 7NTQ ) (a). The 2 Fo-Fc electron-density map, contoured at 1.5 σ, is shown as light grey mesh. (b) Interaction of the ligand (cpd 1 after Cys145 binding) with the 3CL pro S1 pocket. The analysis of the interaction was made using LigPlot+ (v2.2.4). 3CL pro and ligand bonds are shown in brown and purple, respectively. Water molecules are displayed as cyan spheres. Dashed green lines and dashed red lines represent hydrogen bonds and hydrophobic interactions, respectively. The 3CL pro residues that are involved in hydrogen bonds have their name displayed in green whereas the residues making hydrophobic contact(s) are indicated with their name surrounded by red spikes. Atoms involved in hydrophobic contact(s) are surrounded by red spikes.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: Crystallographic structure of the SARS-CoV-2 3CL pro bound to the N-(pyridin-3-ylmethyl)thioformamide moiety (in pink) from the compound 1 (PDB ID: 7NTQ ) (a). The 2 Fo-Fc electron-density map, contoured at 1.5 σ, is shown as light grey mesh. (b) Interaction of the ligand (cpd 1 after Cys145 binding) with the 3CL pro S1 pocket. The analysis of the interaction was made using LigPlot+ (v2.2.4). 3CL pro and ligand bonds are shown in brown and purple, respectively. Water molecules are displayed as cyan spheres. Dashed green lines and dashed red lines represent hydrogen bonds and hydrophobic interactions, respectively. The 3CL pro residues that are involved in hydrogen bonds have their name displayed in green whereas the residues making hydrophobic contact(s) are indicated with their name surrounded by red spikes. Atoms involved in hydrophobic contact(s) are surrounded by red spikes.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Binding Assay

 SARS-CoV-2   3CL  pro inhibition of hit compound 1 and analogs 1A-D, 1x.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: SARS-CoV-2 3CL pro inhibition of hit compound 1 and analogs 1A-D, 1x.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Inhibition

Activity of compounds against  3CL  pro of different human coronaviruses.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: Activity of compounds against 3CL pro of different human coronaviruses.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Activity Assay

Selectivity profile of compounds against human cysteine proteases.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: Selectivity profile of compounds against human cysteine proteases.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques:

F1G cells were infected with SARS-CoV-2 in presence of P-gp inhibitor (CP-100356) and increasing concentrations of compound 1 (top) or GC-376 (bottom). 16 h later, cells were fixed in presence of Hoechst 33342. Infected cells (GFP positive nuclei) and the total number of cells (number of nuclei, Hoechst staining) were determined. Results are presented as the percentage of the control and are the average of four independent experiments. Error bars represent the SEM.

Journal: European Journal of Medicinal Chemistry

Article Title: Novel dithiocarbamates selectively inhibit 3CL protease of SARS-CoV-2 and other coronaviruses

doi: 10.1016/j.ejmech.2023.115186

Figure Lengend Snippet: F1G cells were infected with SARS-CoV-2 in presence of P-gp inhibitor (CP-100356) and increasing concentrations of compound 1 (top) or GC-376 (bottom). 16 h later, cells were fixed in presence of Hoechst 33342. Infected cells (GFP positive nuclei) and the total number of cells (number of nuclei, Hoechst staining) were determined. Results are presented as the percentage of the control and are the average of four independent experiments. Error bars represent the SEM.

Article Snippet: SARS-CoV 3CL protease was purchased from Boston Biochem.

Techniques: Infection, Staining