Metacaspase of Saccharomyces cerevisiae (ScMCA-Ia) presents different catalytic cysteine in a processed and non-processed form

Author(s)

Dalzoto, Laura de Azevedo Maffeis ; Trujilho, Mariana Nascimento Romero ; Santos, Taiz dos Reis ; Costa, Joao Pedro Martins Silva ; Duarte, Ane Caroline Moreira ; Judice, Wagner Alves de Souza ; Marcondes, Marcelo Ferreira ; Machado, Mauricio Ferreira Marcondes

• Document type: Journal article
• Source: Biochemical and Biophysical Research Communications; v. 687, p. 5-pg., 2023-11-10.

Abstract

Metacaspases are cysteine proteases belonging to the CD clan of the C14 family. They possess important characteristics, such as specificity for cleavage after basic residues (Arg/Lys) and dependence on calcium ions to exert their catalytic activity. They are defined by the presence of a large subunit (p20) and a small subunit (p10) and are classified into types I, II, and III. Type I metacaspases have a characteristic pro-domain at the N-terminal of the enzyme, preceding a region rich in glutamine and asparagine. In the yeast Saccharomyces cerevisiae, a type I metacaspase is found. This organism encodes a single metacaspase that participates in the process of programmed cell death by apoptosis. The study focuses on cloning, expressing, and mutating Saccharomyces cerevisiae metacaspase (ScMCA-Ia). Mutations in Cys155 and Cys276 were introduced to investigate autoprocessing mechanisms. Results revealed that Cys155 plays a crucial role in autoprocessing, initiating a conformational change that activates ScMCA-Ia. Comparative analysis with TbMCA-IIa highlighted the significance of the Nterminal region in substrate access to the active site. The study proposes a two-step processing mechanism for type I metacaspases, where an initial processing step generates the active form, followed by a distinct intermolecular processing step. This provides new insights into ScMCA-Ia's activation and function. The findings hold potential implications for understanding cellular processes regulated by metacaspases. Overall, this research significantly advances knowledge in metacaspase biology. (AU)

• FAPESP's process: 22/06394-0 - Obtaining and biochemical characterization of recombinant protozoan metacaspases of clinical interest
• Grantee: Mauricio Ferreira Marcondes Machado
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/27813-8 - Development of beta-lactamase inhibitors of clinical interest
• Grantee: Marcelo Ferreira Marcondes Machado
• Support Opportunities: Regular Research Grants
• FAPESP's process: 21/01503-2 - Evaluation of the effects of glycosaminoglycans on the activity of cysteine protease catatepsin inhibitors
• Grantee: Wagner Alves de Souza Júdice
• Support Opportunities: Regular Research Grants