Chlorpyrifos
Enzymes are protein biomolecules found in all living things and serve as catalysts to quicken various biochemical processes inside cells. Structurally, enzymes bind to reactant particles and retain them together to facilitate the chemical bond-forming and bond-breaking mechanisms. Energetically, enzymes reduce the total energy required for the reaction to start. Competitive and allosteric enzyme inhibitors are similar in reducing enzyme activity (Lira et al., 2019). A key difference between the inhibitors is that an enzyme assumes an inactive form when a competitive inhibitor binds to its active site. In contrast, allosteric inhibition affects the area outside the enzyme’s active region (Lira et al., 2019). In addition, allosteric inhibition alters the confirmation of the enzymes, while competitive inhibition does not interfere with enzyme confirmation.
Mechanism of Action
The moderately poisonous broad-spectrum organo-phosphorus chlorpyrifos used to control insects can be consumed, breathed, or absorbed via the skin. As the substance is broken down during digestion by the body, it turns poisonous and forms a substance called chlorpyrifos oxon (Ur Rahman et al., 2021). The chemical that has been broken down irreversibly binds to acetylcholinesterase, making the enzyme ineffective. As acetylcholine builds up in the synapses, nicotinic and muscarinic receptors are activated (Li and Ehrich, 2022). In essence, chlorpyrifos targets the acetylcholinesterase enzyme, leading to various digestive and respiratory effects.
Experiment
The LD50 test is the main approach to determine the level of chlorpyrifos toxicity in animals and humans. In this case, the dependent variables, human subjects, will be subjected to an oral intake of 3ml of chlorpyrifos, and the LD50 measure will be taken for both groups. In this case, the independent variable is the insecticide quantity. In this experiment, a control group comprising five individuals will be given 30ml of the insecticide. This test hypothesizes that individuals exposed to 3ml of the insecticide will have lower LD50 (0-50mg/kg) levels than the control group, which will have 50-500mg/kg LD50 content. The lower the LD50 values, the higher the level of toxicity.
References
Li, W., & Ehrich, M. (2022). Effects of chlorpyrifos on transient receptor potential channels. Toxicology Letters, 358, 100-104. Web.
Lira, A. L., Ferreira, R. S., Torquato, R. J., Oliva, M. L., Schuck, P., & Sousa, A. A. (2019). Allosteric inhibition of α-thrombin enzymatic activity with ultra small gold nanoparticles. Nanoscale Advances, 1(1), 378–388. Web.
Ur Rahman, H. U., Asghar, W., Nazir, W., Sandhu, M. A., Ahmed, A., & Khalid, N. (2021). A comprehensive review on chlorpyrifos toxicity with special reference to endocrine disruption: Evidence of mechanisms, exposures and mitigation strategies. Science of the Total Environment, 755. Web.