Role of ¿1-pyrroline-5-carboxylate dehydrogenase supports mitochondrial metabolism and host-cell invasion of Trypanosoma cruzi

Mantilla, B.S. ; Paes, L.S. ; Pral, E.M.F. ; Martil, D.E. ; Thiemann, O.H. ; Fernández-Silva, P. (Universidad de Zaragoza) ; Bastos, E.L. ; Silber, A.M.

Resumen: Proline is crucial for energizing critical events throughout the life cycle of Trypanosoma cruzi, the etiological agent of Chagas disease. The proline breakdown pathway consists of two oxidation steps, both of which produce reducing equivalents as follows: the conversion of proline to ¿1-pyrroline-5-carboxylate (P5C), and the subsequent conversion of P5C to glutamate. We have identified and characterized the ¿1-pyrroline-5-carboxy- late dehydrogenase from T. cruzi (TcP5CDH) and report here on how this enzyme contributes to a central metabolic pathway in this parasite. Size-exclusion chromatography, two-dimen- sional gel electrophoresis, and small angle x-ray scattering analysis of TcP5CDH revealed an oligomeric state composed of two subunits of six protomers. TcP5CDH was found to complement a yeast strain deficient in PUT2 activity, confirming the enzyme’s functional role; and the biochemical parameters (Km, kcat, and kcat/Km) of the recombinant TcP5CDH were determined, exhibiting values comparable with those from T. cruzi lysates. In addition, TcP5CDH exhibited mitochondrial staining during the main stages of the T. cruzi life cycle. mRNA and enzymatic activity levels indicated the up-regulation (6-fold change) of TcP5CDH during the infective stages of the parasite. The participation of P5C as an energy source was also demonstrated. Overall, we propose that this enzymatic step is crucial for the viability of both replicative and infective forms of T. cruzi.

Idioma: Inglés

DOI: 10.1074/jbc.M114.574525

Año: 2015

Publicado en: Journal of Biological Chemistry 290, 12 (2015), 7767-7790
ISSN: 0021-9258

Factor impacto JCR: 4.258 (2015)

Categ. JCR: BIOCHEMISTRY & MOLECULAR BIOLOGY rank: 71 / 289 = 0.246 (2015) - Q1 - T1

Factor impacto SCIMAGO: 3.126 - Biochemistry (Q1) - Molecular Biology (Q1) - Cell Biology (Q1)

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Bioquímica y Biolog.Mole. (Dpto. Bioq.Biolog.Mol. Celular)