SE178:/MS01
From Metabolonote
Sample Set Information
| ID | TSE1336 |
|---|---|
| Title | Pathway-level acceleration of glycogen catabolism by a response regulator in the cyanobacterium Synechocystis species PCC 6803. |
| Description | Response regulators of two-component systems play pivotal roles in the transcriptional regulation of responses to environmental signals in bacteria. Rre37, an OmpR-type response regulator, is induced by nitrogen depletion in the unicellular cyanobacterium Synechocystis species PCC 6803. Microarray and quantitative real-time polymerase chain reaction analyses revealed that genes related to sugar catabolism and nitrogen metabolism were up-regulated by rre37 overexpression. Protein levels of GlgP(slr1367), one of the two glycogen phosphorylases, in the rre37-overexpressing strain were higher than those of the parental wild-type strain under both nitrogen-replete and nitrogen-depleted conditions. Glycogen amounts decreased to less than one-tenth by rre37 overexpression under nitrogen-replete conditions. Metabolome analysis revealed that metabolites of the sugar catabolic pathway and amino acids were altered in the rre37-overexpressing strain after nitrogen depletion. These results demonstrate that Rre37 is a pathway-level regulator that activates the metabolic flow from glycogen to polyhydroxybutyrate and the hybrid tricarboxylic acid and ornithine cycle, unraveling the mechanism of the transcriptional regulation of primary metabolism in this unicellular cyanobacterium. |
| Authors | Osanai, T., Oikawa, A., Numata, K., Kuwahara, A., Iijima, H., Doi, Y., Saito, K. and Hirai, M.Y. |
| Reference | Plant Physiol. 2014 Apr;164(4):1831-41. doi: 10.1104/pp.113.232025. |
| Comment |
Analytical Method Details Information
| ID | MS01 |
|---|---|
| Title | CE-MS Analysis |
| Instrument | CE:Agilent CE capillary electrophoresis system (Agilent Technologies) TOF-MS:Agilent G3250AA LC/MSD TOF system (Agilent Technologies) CE-MS:Agilent G1603A |
| Instrument Type | |
| Ionization | ESI |
| Ion Mode | positive and negative |
| Description | Cells were collected by centrifugation at 9,800g for 2 min, followed by freezing in liquid nitrogen. Cells (50–100 mg fresh weight) were suspended in 600 μL of a mixture containing 60% (v/v) methanol and 200 μm each 10-camphorsulfonic acid and trimesic acid as internal standards, and it was mixed using an MT-200 microtube mixer (Tomy) for 20 min at room temperature, followed by centrifugation at 20,500g for 5 min at 4°C. A 300-μL aliquot of the supernatant was centrifuged through a Millipore 5-kD cutoff filter at 10,000g for 90 min. A 250-μL aliquot of the filtrate was dried in a centrifugal concentrator (drying time, 120 min). The residue was dissolved in 20 μL of water and subjected to CE-MS analysis. The CE-MS system and conditions were as described previously (Oikawa et al., 2011). |
| Comment_of_details |
