Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

M. sedula transcriptional response under "strict" carbon-limited autotrophy compared to carbon "rich" autotrophy and heterotrophy

ABSTRACT: Metallosphaera sedula is an extremely thermoacidophilic archaeon that grows heterotrophically on peptides, and chemolithoautotrophically on hydrogen, sulfur, or reduced metals as energy sources. During autotrophic growth, carbon dioxide is incorporated into cellular carbon via the 3-hydroxypropionate /4-hydroxybutyrate cycle (3HP/4HB). To date, all of the steps in the pathway have been connected to enzymes encoded in specific ORFs, except for the one responsible for ligation of coenzyme A (CoA) to 4-hydroxybutyrate (4HB). While several candidates for this step have been identified through bioinformatic analysis of the M. sedula genome, none have been shown to catalyze this biotransformation. Transcriptomic analysis of cells grown under strict H2-CO2 autotrophy was used elucidate additional candidate genes involved in carbon fixation and identify the genes which encode for 4HB-CoA synthetase. Three slide loop for Mse cells includes 3 conditions tested in duplicate (biological repeats from tandem fermentors): autotrophic carbon limited (ACL), autotrophic carbon rich (ACR), and heterotrophic (HTR). Half of an RNA sample for one condition was labeled with Cy3 while the other half was labeled with Cy5. The two differently labeled samples were run on different slides. Each probe is spotted on each slide 5 times (5 replicates; spot intensities for all replicates on slide provided in associated raw data file).

ORGANISM(S): Metallosphaera sedula DSM 5348

SUBMITTER: Aaron Hawkins

PROVIDER: E-GEOD-39944 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Role of 4-hydroxybutyrate-CoA synthetase in the CO2 fixation cycle in thermoacidophilic archaea.

Hawkins Aaron S AS Han Yejun Y Bennett Robert K RK Adams Michael W W MW Adams Michael W W MW Kelly Robert M RM

The Journal of biological chemistry 20121220 6

Metallosphaera sedula is an extremely thermoacidophilic archaeon that grows heterotrophically on peptides and chemolithoautotrophically on hydrogen, sulfur, or reduced metals as energy sources. During autotrophic growth, carbon dioxide is incorporated into cellular carbon via the 3-hydroxypropionate/4-hydroxybutyrate cycle (3HP/4HB). To date, all of the steps in the pathway have been connected to enzymes encoded in specific genes, except for the one responsible for ligation of coenzyme A (CoA) t ...[more]

PMID: 23258541

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