skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: The Shewanella oneidensis MR-1 Fluxome under Various OxygenConditions

Abstract

The central metabolic fluxes of Shewanella oneidensis MR-1were examined under carbon-limited (aerobic) and oxygen-limited(micro-aerobic) chemostat conditions using 13C labeled lactate as thesole carbon source. The carbon labeling patterns of key amino acids inbiomass were probed using both GC-MS and 13C-NMR. Based on the genomeannotation, a metabolic pathway model was constructed to quantify thecentral metabolic flux distributions. The model showed that thetricarboxylic acid (TCA) cycle is the major carbon metabolism route underboth conditions. The Entner-Doudoroff and pentose phosphate pathways weremainly utilized for biomass synthesis (flux below 5 percent of thelactate uptake rate). The anapleurotic reactions (pyruvate to malate andoxaloacetate to phosphoenolpyruvate) and the glyoxylate shunt wereactive. Under carbon-limited conditions, a substantial amount of carbonwas oxidized via the highly reversible serine metabolic pathway. Fluxesthrough the TCA cycle were less whereas acetate production was more underoxygen limitation than under carbon limitation. Although fluxdistributions under aerobic, micro-aerobic, and shake-flask cultureconditions were dramatically different, the relative flux ratios of thecentral metabolic reactions did not vary significantly. Hence, S.oneidensis metabolism appears to be quite robust to environmentalchanges. Our study also demonstrates the merit of coupling GC-MS with 13CNMR for metabolic flux analysis to reduce the use of 13C labeledsubstrates and to obtain more accurate flux values.

Authors:
; ; ;
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE Director. Office of Science. Biological andEnvironmental Research
OSTI Identifier:
919835
Report Number(s):
LBNL-59869
R&D Project: GTL2KK; BnR: KP1102010; TRN: US200822%%585
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: American Society for Microbiology; Journal Volume: 73; Journal Issue: 3; Related Information: Journal Publication Date: 02/2007
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; AMINO ACIDS; BIOLOGICAL PATHWAYS; CARBON; CARBON SOURCES; OXYGEN; METABOLISM; micro-aerobic isotopomer model futile cycles serine metabolismflux ratio

Citation Formats

Tang, Yinjie J., Hwang, Judy S., Wemmer, David E., and Keasling, Jay D. The Shewanella oneidensis MR-1 Fluxome under Various OxygenConditions. United States: N. p., 2006. Web.
Tang, Yinjie J., Hwang, Judy S., Wemmer, David E., & Keasling, Jay D. The Shewanella oneidensis MR-1 Fluxome under Various OxygenConditions. United States.
Tang, Yinjie J., Hwang, Judy S., Wemmer, David E., and Keasling, Jay D. Fri . "The Shewanella oneidensis MR-1 Fluxome under Various OxygenConditions". United States. doi:. https://www.osti.gov/servlets/purl/919835.
@article{osti_919835,
title = {The Shewanella oneidensis MR-1 Fluxome under Various OxygenConditions},
author = {Tang, Yinjie J. and Hwang, Judy S. and Wemmer, David E. and Keasling, Jay D.},
abstractNote = {The central metabolic fluxes of Shewanella oneidensis MR-1were examined under carbon-limited (aerobic) and oxygen-limited(micro-aerobic) chemostat conditions using 13C labeled lactate as thesole carbon source. The carbon labeling patterns of key amino acids inbiomass were probed using both GC-MS and 13C-NMR. Based on the genomeannotation, a metabolic pathway model was constructed to quantify thecentral metabolic flux distributions. The model showed that thetricarboxylic acid (TCA) cycle is the major carbon metabolism route underboth conditions. The Entner-Doudoroff and pentose phosphate pathways weremainly utilized for biomass synthesis (flux below 5 percent of thelactate uptake rate). The anapleurotic reactions (pyruvate to malate andoxaloacetate to phosphoenolpyruvate) and the glyoxylate shunt wereactive. Under carbon-limited conditions, a substantial amount of carbonwas oxidized via the highly reversible serine metabolic pathway. Fluxesthrough the TCA cycle were less whereas acetate production was more underoxygen limitation than under carbon limitation. Although fluxdistributions under aerobic, micro-aerobic, and shake-flask cultureconditions were dramatically different, the relative flux ratios of thecentral metabolic reactions did not vary significantly. Hence, S.oneidensis metabolism appears to be quite robust to environmentalchanges. Our study also demonstrates the merit of coupling GC-MS with 13CNMR for metabolic flux analysis to reduce the use of 13C labeledsubstrates and to obtain more accurate flux values.},
doi = {},
journal = {American Society for Microbiology},
number = 3,
volume = 73,
place = {United States},
year = {Fri Mar 17 00:00:00 EST 2006},
month = {Fri Mar 17 00:00:00 EST 2006}
}