Colombian Scorpion Centruroides margaritatus: Purification and Characterization of a Gamma Potassium Toxin with Full-Block Activity on the hERG1 Channel
Abstract
:1. Introduction
2. Results
2.1. Peptide Isolation
2.2. CmERG1 Primary Structure
2.3. CmERG1 Block Action on hERG1 Channels
2.4. CmERG1 Does Not Modify the Activation and Inactivation Kinetics of hERG1 Channels
2.5. Models of Channel-Toxin Interactions
3. Discussion
4. Conclusions
5. Materials and Methods
5.1. Venom Source, Chemical and Reagents
5.2. Peptide Purification
5.3. Mass Spectrometry and Sequence by Edman Degradation
5.4. Reduction and Alkylation
5.5. Amino Acid Sequence Comparison of Peptide
5.6. Electrophysiology
5.6.1. Cells and Solutions
5.6.2. Patch-Clamp Recordings and Data Analysis
5.6.3. Statistical Analysis
5.7. Modeling of the Toxin-Channel Encounter Complexes
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Fraction | Molecular Mass (Da) |
---|---|
F13 | 3704.97 |
F14 | 3718.19 |
F15 | 3543.74/4178.82/3228.7 |
F16 | 3571.8/4191.71 |
F17 | 3572.21 |
F18 | 4177.69 |
F19 | 4176.97 |
F20 | 2820.1/3980.01 |
F21 | 2819.8/3979.7 |
F22 | 4916.12/6898.7/7942.6 |
* F23 | 6838.9/4792.1 |
F31 | 6793.37/3376.05 |
Fraction | Retention Time (min) | Molecular Mass (Da) |
---|---|---|
FII-6 | 24.5 | 2820.5 |
FII-6 | 27.4 | 4792.8 |
FII-6 | 28.7 | 4045.7 |
FII-6 | 29.1 | 4309.5; 3994 |
FII-6 | 32.3 | 6992 |
FII-6 | 33.4 | 4177; 6470 |
FII-6 | 34.6 | 6613.5; 6868.1 |
FII-6 | 35.4 | 6724 |
FII-7 | 20.66 | 3229 |
FII-7 | 28.4 | 4045.6 |
FII-7 | 29.2 | 6838.8 |
FII-8 | 23.2 | 4177.5 |
FII-8 | 25.2 | 3980.2 |
FII-8 | 29.2 | 8475.1; 4133.5 |
FII-8 | 37.9 | 7547.6; 7998.1 |
FII-9 | 21.6 | 3704.2; 3815.1 |
FII-9 | 26.1 | 4178.4 |
FII-9 | 26.4 | 8475.8; 4178 |
FII-9 | 27 | 7498.0; 7620.7 |
FII-9 | 27.2 | 7497.4; 7618 |
FII-10 | 18.7 | 3703.7; 3718.2 |
FII-10 | 23.2 | 8441; 5027.8; 4915 |
FII-10 | 28.6 | 7497; 7620 |
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Beltrán-Vidal, J.; Carcamo-Noriega, E.; Pastor, N.; Zamudio-Zuñiga, F.; Guerrero-Vargas, J.A.; Castaño, S.; Possani, L.D.; Restano-Cassulini, R. Colombian Scorpion Centruroides margaritatus: Purification and Characterization of a Gamma Potassium Toxin with Full-Block Activity on the hERG1 Channel. Toxins 2021, 13, 407. https://0-doi-org.brum.beds.ac.uk/10.3390/toxins13060407
Beltrán-Vidal J, Carcamo-Noriega E, Pastor N, Zamudio-Zuñiga F, Guerrero-Vargas JA, Castaño S, Possani LD, Restano-Cassulini R. Colombian Scorpion Centruroides margaritatus: Purification and Characterization of a Gamma Potassium Toxin with Full-Block Activity on the hERG1 Channel. Toxins. 2021; 13(6):407. https://0-doi-org.brum.beds.ac.uk/10.3390/toxins13060407
Chicago/Turabian StyleBeltrán-Vidal, José, Edson Carcamo-Noriega, Nina Pastor, Fernando Zamudio-Zuñiga, Jimmy Alexander Guerrero-Vargas, Santiago Castaño, Lourival Domingos Possani, and Rita Restano-Cassulini. 2021. "Colombian Scorpion Centruroides margaritatus: Purification and Characterization of a Gamma Potassium Toxin with Full-Block Activity on the hERG1 Channel" Toxins 13, no. 6: 407. https://0-doi-org.brum.beds.ac.uk/10.3390/toxins13060407