title: Using photosystem I as a reporter protein for ¹³C analysis in a coculture containing cyanobacterium and a heterotrophic bacterium.
abstract: (13)C metabolism analysis of a microbial community is often hindered by the time-consuming and complicated separation procedure for a single species. However, a "reporter protein," produced uniquely by one cell type, retains (13)C fingerprint information in microbial consortia. This study describes the use of photosystem I (PSI), a multi-subunit protein complex universally found in oxygenic phototrophs, as a reliable reporter protein to probe microalgal metabolism (i.e., cyanobacterium Synechocystis sp. PCC 6803) in a mixed culture with heterotrophic bacteria (i.e., Escherichia coli). We demonstrate that efficient purification of PSI and subsequent (13)C-based amino acid analyses may decipher photomixotrophic metabolism of Synechocystis 6803 in the coculture. This study also indicates that a supplement of NaHCO3 at high concentration could significantly improve the robustness of cyanobacterial growth against bacterial contamination.
authors.affiliation: Department of Energy, Environmental, and Chemical Engineering, Washington University, St. Louis, MO 63130, USA.
authors.forename: Le
authors.initials: L
authors.lastname: You
authors.affiliation: Department of Biology, Washington University, St. Louis, MO 63130, USA.
authors.forename: Haijun
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Biology, Washington University, St. Louis, MO 63130, USA; Department of Chemistry, Washington University, St. Louis, MO 63130, USA.
authors.forename: Robert E
authors.initials: RE
authors.lastname: Blankenship
authors.affiliation: Department of Energy, Environmental, and Chemical Engineering, Washington University, St. Louis, MO 63130, USA. Electronic address: yinjie.tang@seas.wustl.edu.
authors.forename: Yinjie J
authors.initials: YJ
authors.lastname: Tang
mesh_terms: D002247:Carbon Isotopes / Q000378:metabolism; D018920:Coculture Techniques / Q000379:methods*; D004926:Escherichia coli / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D052836:Heterotrophic Processes; D045331:Photosystem I Protein Complex / Q000378:metabolism*; D017693:Sodium Bicarbonate / Q000494:pharmacology; D046939:Synechocystis / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism*
chemical_list: D002247:Carbon Isotopes; D045331:Photosystem I Protein Complex; D017693:Sodium Bicarbonate
keywords: (13)C fingerprint; Contamination; Metabolism; Microbial consortia; Synechocystis