Dataset Information

Transcript map of Shewanella oneidensis MR-1

ABSTRACT: High-resolution tiling analysis of the MR-1 transcriptome under diverse growth conditions The conditions include aerobic growth in Luria-Bertani broth (LB), aerobic growth in defined lactate minimal medium, anaerobic growth in defined lactate minimal medium with 20mM dimethyl sulfoxide as the electron acceptor, anaerobic growth in defined lactate minimal medium with 10mM iron (III) citrate as the electron acceptor, 10 minutes post heat shock at 42oC see GSE39468 for tiling data on lactate minimal media

ORGANISM(S): Shewanella oneidensis MR-1

PROVIDER: GSE45217 | GEO | 2013/03/18

SECONDARY ACCESSION(S): PRJNA193220

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Shewanella oneidensis MR-1 is a facultative anaerobe that grows by respiration using a variety of electron acceptors. This organism serves as a model to study how bacteria thrive in redox-stratified environments. A glucose-utilizing engineered derivative of MR-1 has been reported to be unable to grow in glucose minimal medium (GMM) in the absence of electron acceptors, despite this strain having a complete set of genes for reconstructing glucose to lactate fermentative pathways. To gain insights into why MR-1 is incapable of fermentative growth, this study examined a hypothesis that this strain is programmed to repress the expression of some carbon metabolic genes in the absence of electron acceptors. Comparative transcriptomic analyses of the MR-1 derivative were conducted in the presence and absence of fumarate as an electron acceptor, and these found that the expression of many genes involved in carbon metabolism required for cell growth, including several tricarboxylic acid (TCA) cycle genes, was significantly downregulated in the absence of fumarate. This finding suggests a possibility that MR-1 is unable to grow fermentatively on glucose in minimal media owing to the shortage of nutrients essential for cell growth, such as amino acids. This idea was demonstrated in subsequent experiments that showed that the MR-1 derivative fermentatively grows in GMM containing tryptone or a defined mixture of amino acids. We suggest that gene regulatory circuits in MR-1 are tuned to minimize energy consumption under electron acceptor-depleted conditions, and that this results in defective fermentative growth in minimal media. IMPORTANCE It is an enigma why S. oneidensis MR-1 is incapable of fermentative growth despite having complete sets of genes for reconstructing fermentative pathways. Understanding the molecular mechanisms behind this defect will facilitate the development of novel fermentation technologies for the production of value-added chemicals from biomass feedstocks, such as electro-fermentation. The information provided in this study will also improve our understanding of the ecological strategies of bacteria living in redox-stratified environments.

Dataset Information

Transcript map of Shewanella oneidensis MR-1

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure