Intracellular crowding defines the mode and sequence of substrate uptake by Escherichia coli and constrains its metabolic activity.
Proc Natl Acad Sci U S A
; 104(31): 12663-8, 2007 Jul 31.
Article
em En
| MEDLINE
| ID: mdl-17652176
ABSTRACT
The influence of the high intracellular concentration of macromolecules on cell physiology is increasingly appreciated, but its impact on system-level cellular functions remains poorly quantified. To assess its potential effect, here we develop a flux balance model of Escherichia coli cell metabolism that takes into account a systems-level constraint for the concentration of enzymes catalyzing the various metabolic reactions in the crowded cytoplasm. We demonstrate that the model's predictions for the relative maximum growth rate of wild-type and mutant E. coli cells in single substrate-limited media, and the sequence and mode of substrate uptake and utilization from a complex medium are in good agreement with subsequent experimental observations. These results suggest that molecular crowding represents a bound on the achievable functional states of a metabolic network, and they indicate that models incorporating this constraint can systematically identify alterations in cellular metabolism activated in response to environmental change.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Escherichia coli
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2007
Tipo de documento:
Article
País de afiliação:
Estados Unidos
País de publicação:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA