• Categoría: Artículo
  • Título: Bistable behaviour and medium-dependent post-translational regulation of the tryptophanase operon regulatory pathway in Echerichia coli
  • Autor (es): David I. Orozco-Gómez, Juan Eduardo Sosa-Hernández, Óscar Adrián Gallardo-Navarro, Jesús Santana-Solano, Moisés Santillán
  • Revista: Scientific Reports
  • Volumen: 9
  • Páginas:
  • Formato: Enlace
  • Subido por: Juan Eduardo

Bistable behaviour and medium-dependent post-translational regulation of the tryptophanase operon regulatory pathway in Echerichia coli

David I. Orozco-Gómez, Juan Eduardo Sosa-Hernández, Óscar Adrián Gallardo-Navarro, Jesús Santana-Solano, Moisés Santillán

The present work is aimed at studying the dynamic behaviour of the tryptopnanase (tna) operon, which encodes the proteins necessary to uptake and metabolise tryptophan to use it as a carbon source in the absence of glucose. To this end, we designed a micro-bioreactor capable of driving a bacterial culture to a stationary state. This allowed us to explore (at the single cell level) the tna operon steady-state dynamics under multiple culture conditions. Our experimental results suggest that the tna operon is bistable for a specific range of environmental tryptophan and glucose concentrations, and evidence that both reagents play a role on the activation of the enzyme in charge of metabolising tryptophan: tryptophanase (TnaA). Based on our experimental data and the already known regulatory mechanisms, we developed a mathematical model for the tna operon regulatory pathway. Our modelling results reinforce the …