Obtaining the recombinant enzyme acetylcholinesterase from the fall armyworm, Spodoptera frugiperda, for structural studies

• Grant number: 12/17222-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): February 01, 2013
• Effective date (End): June 30, 2014
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: Dulce Helena Ferreira de Souza
• Grantee: Guilherme Keppe Zanini
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

In Brazil, the fall armyworm, Spodoptera frugiperda (JE Smith, 1797), is the major pest of maize causing big losses for the producer, so the insect's control is very important. S. frugiperda is present in hot and humid climates as the tropical and subtropical zones and their distribution is very broad, covering not only Brazil, but countries from different locations. Despite the preference for cornfields, the larval stage of S. frugiperda also has importance in crops of rice and wheat too.One approach to control this pest is the use of insecticides as the organophosphates and carbamates, which inhibit a essential enzyme for the insect survival, the Acetylcholinesterase (AChE). This enzyme is responsible for the hydrolysis of the neurotransmitter acetylcholine, and has been insecticide's target. Alzheimer and Glaucoma diseases are related to the achetylcholine hydrolysis, so the enzyme is also a target to new drugs. Once the catalytic site of insect and human AChE has a high similarity, insecticides also inhibit the enzyme in humans, which is not desirable. To minimize side effects, searches for more specifically inhibitors of the insect's AChE are required. The knowledge of the three dimensional structure of the enzyme is essential to find differences among the human and the insect AChE, because of that we propose in project the construction of a system for obtaining pure recombinant AChE enzyme for future structural studies. The gene encoding the synthesis of AChE S. frugiperda will be cloned into a suitable vector and then expressed in P. pastoris cells. The protein will be purified and characterized enzymatically. (AU)