Dataset Information

Revealing the functions of the transketolase enzyme isoforms in Rhodopseudomonas palustris using a systems biology approach.

ABSTRACT:

Background

Rhodopseudomonas palustris (R. palustris) is a purple non-sulfur anoxygenic phototrophic bacterium that belongs to the class of proteobacteria. It is capable of absorbing atmospheric carbon dioxide and converting it to biomass via the process of photosynthesis and the Calvin-Benson-Bassham (CBB) cycle. Transketolase is a key enzyme involved in the CBB cycle. Here, we reveal the functions of transketolase isoforms I and II in R. palustris using a systems biology approach.

Methodology/principal findings

By measuring growth ability, we found that transketolase could enhance the autotrophic growth and biomass production of R. palustris. Microarray and real-time quantitative PCR revealed that transketolase isoforms I and II were involved in different carbon metabolic pathways. In addition, immunogold staining demonstrated that the two transketolase isoforms had different spatial localizations: transketolase I was primarily associated with the intracytoplasmic membrane (ICM) but transketolase II was mostly distributed in the cytoplasm. Comparative proteomic analysis and network construction of transketolase over-expression and negative control (NC) strains revealed that protein folding, transcriptional regulation, amino acid transport and CBB cycle-associated carbon metabolism were enriched in the transketolase I over-expressed strain. In contrast, ATP synthesis, carbohydrate transport, glycolysis-associated carbon metabolism and CBB cycle-associated carbon metabolism were enriched in the transketolase II over-expressed strain. Furthermore, ATP synthesis assays showed a significant increase in ATP synthesis in the transketolase II over-expressed strain. A PEPCK activity assay showed that PEPCK activity was higher in transketolase over-expressed strains than in the negative control strain.

Conclusions/significance

Taken together, our results indicate that the two isoforms of transketolase in R. palustris could affect photoautotrophic growth through both common and divergent metabolic mechanisms.

SUBMITTER: Hu CW

PROVIDER: S-EPMC3234253 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Publications

Revealing the functions of the transketolase enzyme isoforms in Rhodopseudomonas palustris using a systems biology approach.

Hu Chia-Wei CW Chang Ya-Ling YL Chen Shiang Jiuun SJ Kuo-Huang Ling-Long LL Liao James C JC Huang Hsuan-Cheng HC Juan Hsueh-Fen HF

PloS one 20111208 12

<h4>Background</h4>Rhodopseudomonas palustris (R. palustris) is a purple non-sulfur anoxygenic phototrophic bacterium that belongs to the class of proteobacteria. It is capable of absorbing atmospheric carbon dioxide and converting it to biomass via the process of photosynthesis and the Calvin-Benson-Bassham (CBB) cycle. Transketolase is a key enzyme involved in the CBB cycle. Here, we reveal the functions of transketolase isoforms I and II in R. palustris using a systems biology approach.<h4>Me ...[more]

PMID: 22174789

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Dataset Information

Revealing the functions of the transketolase enzyme isoforms in Rhodopseudomonas palustris using a systems biology approach.

Background

Methodology/principal findings

Conclusions/significance

Publications

Revealing the functions of the transketolase enzyme isoforms in Rhodopseudomonas palustris using a systems biology approach.

Similar Datasets

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