title: Differences in energy transfer of a cyanobacterium, Synechococcus sp. PCC 7002, grown in different cultivation media.
abstract: Currently, cyanobacteria are regarded as potential biofuel sources. Large-scale cultivation of cyanobacteria in seawater is of particular interest because seawater is a low-cost medium. In the present study, we examined differences in light-harvesting and energy transfer processes in the cyanobacterium Synechococcus sp. PCC 7002 grown in different cultivation media, namely modified A medium (the optimal growth medium for Synechococcus sp. PCC 7002) and f/2 (a seawater medium). The concentrations of nitrate and phosphate ions were varied in both media. Higher nitrate ion and/or phosphate ion concentrations yielded high relative content of phycobilisome. The cultivation medium influenced the energy transfers within phycobilisome, from phycobilisome to photosystems, within photosystem II, and from photosystem II to photosystem I. We suggest that the medium also affects charge recombination at the photosystem II reaction center and formation of a chlorophyll-containing complex.
authors.affiliation: Graduate School of Science, Kobe University, Kobe, 657-8501, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Niki
authors.forename: Shimpei
authors.initials: S
authors.lastname: Aikawa
authors.forename: Makio
authors.initials: M
authors.lastname: Yokono
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kondo
authors.forename: Seiji
authors.initials: S
authors.lastname: Akimoto
mesh_terms: D002734:Chlorophyll / Q000378:metabolism; D003470:Culture Media; D004735:Energy Transfer / Q000187:drug effects*; D005453:Fluorescence; D008027:Light; D009566:Nitrates / Q000494:pharmacology*; D009584:Nitrogen / Q000172:deficiency; D010710:Phosphates / Q000172:deficiency / Q000494:pharmacology*; D045331:Photosystem I Protein Complex / Q000187:drug effects / Q000378:metabolism; D045332:Photosystem II Protein Complex / Q000187:drug effects / Q000378:metabolism; D045524:Phycobilisomes / Q000187:drug effects / Q000378:metabolism; D046940:Synechococcus / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects
chemical_list: D003470:Culture Media; D009566:Nitrates; D010710:Phosphates; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D045524:Phycobilisomes; D002734:Chlorophyll; D009584:Nitrogen