title: Respiration accumulates Calvin cycle intermediates for the rapid start of photosynthesis in Synechocystis sp. PCC 6803.
abstract: We tested the hypothesis that inducing photosynthesis in cyanobacteria requires respiration. A mutant deficient in glycogen phosphorylase (∆GlgP) was prepared in Synechocystis sp. PCC 6803 to suppress respiration. The accumulated glycogen in ΔGlgP was 250-450% of that accumulated in wild type (WT). The rate of dark respiration in ΔGlgP was 25% of that in WT. In the dark, P700(+) reduction was suppressed in ΔGlgP, and the rate corresponded to that in (2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone)-treated WT, supporting a lower respiration rate in ∆GlgP. Photosynthetic O2-evolution rate reached a steady-state value much slower in ∆GlgP than in WT. This retardation was solved by addition of d-glucose. Furthermore, we found that the contents of Calvin cycle intermediates in ∆GlgP were lower than those in WT under dark conditions. These observations indicated that respiration provided the carbon source for regeneration of ribulose 1,5-bisphosphate in order to drive the rapid start of photosynthesis.
authors.affiliation: a Faculty of Agriculture, Department of Biological and Environmental Science, Graduate School of Agricultural Science , Kobe University , Kobe , Japan.
authors.forename: Ginga
authors.initials: G
authors.lastname: Shimakawa
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Hasunuma
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kondo
authors.forename: Mami
authors.initials: M
authors.lastname: Matsuda
authors.forename: Amane
authors.initials: A
authors.lastname: Makino
authors.forename: Chikahiro
authors.initials: C
authors.lastname: Miyake
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003991:Dibromothymoquinone / Q000494:pharmacology; D015870:Gene Expression; D005947:Glucose / Q000378:metabolism; D006003:Glycogen / Q000096:biosynthesis; D024981:Glycogen Phosphorylase / Q000172:deficiency / Q000235:genetics; D009154:Mutation; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism*; D017440:Photoperiod; D010788:Photosynthesis / Q000187:drug effects / Q000235:genetics*; D012274:Ribulosephosphates / Q000096:biosynthesis*; D046939:Synechocystis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D012274:Ribulosephosphates; C001933:ribulose-1,5 diphosphate; D003991:Dibromothymoquinone; D006003:Glycogen; D024981:Glycogen Phosphorylase; D005947:Glucose; D010100:Oxygen
keywords: cyanobacteria; glycogen phosphorylase; photosynthesis; respiration