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An Electrochemical Approach to Follow and Evaluate the Kinetic Catalysis of Ricin on hsDNA.

ABSTRACT: International authorities classify the ricin toxin, present in castor seeds, as a potential agent for use in bioterrorism. Therefore, the detection, identification, and characterization of ricin are considered the first actions for its risk assessment during a suspected exposure, parallel to the development of therapeutic and medical countermeasures. In this study, we report the kinetic analysis of electro-oxidation of adenine released from hsDNA by the catalytic action of ricin by square wave voltammetry. The results suggest that ricin-mediated adenine release exhibited an unusual kinetic profile, with a progress curve controlled by the accumulation of the product and the values of the kinetic constants of 46.6 µM for Km and 2000 min-1 for kcat, leading to a catalytic efficiency of 7.1 × 105 s-1 M-1.

SUBMITTER: Oliveira G

PROVIDER: S-EPMC8145570 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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An Electrochemical Approach to Follow and Evaluate the Kinetic Catalysis of Ricin on hsDNA.

Oliveira George G Schneedorf José Maurício JM

Life (Basel, Switzerland) 20210429 5

International authorities classify the ricin toxin, present in castor seeds, as a potential agent for use in bioterrorism. Therefore, the detection, identification, and characterization of ricin are considered the first actions for its risk assessment during a suspected exposure, parallel to the development of therapeutic and medical countermeasures. In this study, we report the kinetic analysis of electro-oxidation of adenine released from hsDNA by the catalytic action of ricin by square wave v ...[more]

PMID: 33946642

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