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Manipulation of the anoxic metabolism in escherichia coli by ArcB deletion variants in the ArcBA two-component system
- Source :
- Appl. Environ. Microbiol. 2012;78(24):8784-8794, Biblioteca Digital (UBA-FCEN), Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales, instacron:UBA-FCEN
- Publication Year :
- 2012
-
Abstract
- Bioprocesses conducted under conditions with restricted O2 supply are increasingly exploited for the synthesis of reduced biochemicals using different biocatalysts. The model facultative anaerobe Escherichia coli has elaborate sensing and signal transduction mechanisms for redox control in response to the availability of O2 and other electron acceptors. The ArcBA two-component system consists of ArcB, a membrane-associated sensor kinase, and ArcA, the cognate response regulator. The tripartite hybrid kinase ArcB possesses a transmembrane, a PAS, a primary transmitter (H1), a receiver (D1), and a phosphotransfer (H2) domain. Metabolic fluxes were compared under anoxic conditions in a wild-type E. coli strain, its ΔarcB derivative, and two partial arcB deletion mutants in which ArcB lacked either the H1 domain or the PAS-H1-D1 domains. These analyses revealed that elimination of different segments in ArcB determines a distinctive distribution of D-glucose catabolic fluxes, different from that observed in the ΔarcB background. Metabolite profiles, enzyme activity levels, and gene expression patterns were also investigated in these strains. Relevant alterations were observed at the P-enol-pyruvate/pyruvate and acetyl coenzyme A metabolic nodes, and the formation of reduced fermentation metabolites, such as succinate, D-lactate, and ethanol, was favored in the mutant strains to different extents compared to the wild-type strain. These phenotypic traits were associated with altered levels of the enzymatic activities operating at these nodes, as well as with elevated NADH/NAD+ ratios. Thus, targeted modification of global regulators to obtain different metabolic flux distributions under anoxic conditions is emerging as an attractive tool for metabolic engineering purposes. © 2012, American Society for Microbiology. Fil:Ruiz, J.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:de Almeida, A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Méndez, B.S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.
- Subjects :
- Facultative anaerobes
Enzymatic activities
Electron acceptor
Metabolic flux
Succinic Acid
Signal transduction
Plants (botany)
biochemical composition
Metabolites
membrane protein
genetics
Anaerobiosis
glucose
Sensor kinase
fermentation
Sequence Deletion
arcA protein, E coli
anoxic conditions
alcohol
Escherichia coli Proteins
repressor protein
article
Phospho-transfer
protein kinase
Wild types
Enzymes
Response regulators
D-lactate
Two component systems
D-glucose
Metabolic Networks and Pathways
Bacterial Outer Membrane Proteins
enzymology
Mutant strain
arcB protein, E coli
redox conditions
Arca
Escherichia coli protein
outer membrane protein
Deletion mutants
Signal transduction mechanism
Escherichia coli
Lactic Acid
Wild-type strain
nicotinamide adenine dinucleotide
Acetyl coenzyme A
Metabolite profiles
Ethanol
gene deletion
Deletion variants
Phenotypic traits
E. coli
Membrane Proteins
anaerobic growth
coliform bacterium
NAD
Gene expression patterns
Repressor Proteins
Transmembranes
Metabolism
Gene expression
mutation
Metabolic flux distribution
Bioprocesses
oxygen
Protein Kinases
catalyst
Subjects
Details
- Language :
- English
- Database :
- OpenAIRE
- Journal :
- Appl. Environ. Microbiol. 2012;78(24):8784-8794, Biblioteca Digital (UBA-FCEN), Universidad Nacional de Buenos Aires. Facultad de Ciencias Exactas y Naturales, instacron:UBA-FCEN
- Accession number :
- edsair.od......3056..86f1ea059f00a34e1f48e17231984bcc