Physiological analysis of Methylobacterium extorquens AM1 grown in continuous and batch cultures.
Chemostat cultures of Methylobacterium extorquens AM1 grown on methanol or succinate at a range of dilution rates were compared to batch cultures in terms of enzyme levels, poly-beta-hydroxybutyrate content, and intracellular concentrations of adenine and pyridine nucleotides. In both chemostat and batch cultures, enzymes specific to C1 metabolism were up-regulated during growth on methanol and down-regulated during growth on succinate, polyhydroxybutyrate levels were higher on succinate, intracellular ATP levels and the energy charge were higher during growth on methanol, while the pools of reducing equivalents were higher during growth on succinate. For most of the tested parameters, little alteration occurred in response to growth rate. Overall, we conclude that the chemostat cultivation conditions developed in this study roughly mimic the growth in batch cultures, but provide a better control over the culturing conditions and a better data reproducibility, which are important for integrative functional studies. This study provides baseline data for future work using chemostat cultures, defining key similarities and differences in the physiology compared to existing batch culture data.
Guo
Xiaofeng
X
Department of Chemical Engineering, University of Washington, Box 352180, Seattle, WA 98195, USA.
Lidstrom
Mary E
ME
D000227:Adenine Nucleotides / Q000032:analysis; D001426:Bacterial Proteins / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D004798:Enzymes / Q000032:analysis; D006885:Hydroxybutyrates / Q000032:analysis; D000432:Methanol / Q000378:metabolism; D020601:Methylobacterium extorquens / Q000737:chemistry* / Q000254:growth & development / Q000378:metabolism*; D011091:Polyesters / Q000032:analysis; D011741:Pyrimidine Nucleosides / Q000032:analysis; D019802:Succinic Acid / Q000378:metabolism; D000094122:Polyhydroxybutyrates
D000227:Adenine Nucleotides; D001426:Bacterial Proteins; D004798:Enzymes; D006885:Hydroxybutyrates; D000432:Methanol; D011091:Polyesters; D011741:Pyrimidine Nucleosides; D019802:Succinic Acid; C003182:poly-beta-hydroxybutyrate; D000094122:Polyhydroxybutyrates