One of the NAD kinases, sll1415 , is required for the glucose metabolism of Synechocystis sp. PCC 6803
Autor: | Yuuma Ishikawa, Yukako Hihara, Toshiki Ishikawa, Maki Kawai-Yamada, Masatoshi Yamaguchi, Atsuko Miyagi, Yasuko Kaneko, Minoru Nagano |
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Rok vydání: | 2019 |
Předmět: |
0106 biological sciences
0301 basic medicine Glucose-6-Phosphate Dehydrogenase Plant Science Pentose phosphate pathway Biology Gluconates 01 natural sciences Pentose Phosphate Pathway 03 medical and health sciences chemistry.chemical_compound Bacterial Proteins Glucose dehydrogenase Genetics Metabolomics Glycogen Catabolism Phosphogluconate Dehydrogenase Synechocystis Cell Biology Metabolism Phosphotransferases (Alcohol Group Acceptor) Metabolic pathway Glucose 030104 developmental biology chemistry Biochemistry Mutation Metabolome NAD+ kinase Metabolic Networks and Pathways 010606 plant biology & botany |
Zdroj: | The Plant Journal. 98:654-666 |
ISSN: | 1365-313X 0960-7412 |
Popis: | Pyridine nucleotides (NAD(P)(H)) are electron carriers that are the driving forces in various metabolic pathways. Phosphorylation of NAD(H) to NADP(H) is performed by the enzyme NAD kinase (NADK). Synechocystis sp. PCC 6803 harbors two genes (sll1415 and slr0400) that encode proteins with NADK homology. When genetic mutants for sll1415 and slr0400 (Δ1415 and Δ0400, respectively) were cultured under photoheterotrophic growth conditions only the Δ1415 cells showed a growth defect. In wild-type cells, the sll1415 transcript accumulated after the cells were transferred to photoheterotrophic conditions. Furthermore, NAD(P)(H) measurements demonstrated that a dynamic metabolic conversion was implemented during the adaptation from photoautotrophic to photoheterotrophic conditions. Electron microscopy observation and biochemistry quantification demonstrated the accumulation of glycogen in the Δ1415 cells under photoheterotrophic conditions at 96 h. Quantitative real-time reverse transcription PCR (qRT-PCR) demonstrated the accumulation of mRNAs that encoded glycogen biosynthesis-related enzymes in photoheterotrophic Δ1415 cells. At 96 h, enzyme activity measurement in the photoheterotrophic Δ1415 cells demonstrated that the activities of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were decreased, but the activities of glucose dehydrogenase were increased. Furthermore, metabolomics analysis demonstrated that the Δ1415 cells showed increased glucose-6-phosphate and 6-phosphogluconate content at 96 h. Therefore, sll1415 has a significant function in the oxidative pentose phosphate (OPP) pathway for catabolism of glucose under photoheterotrophic conditions. Additionally, it is presumed that the slr0400 had a different role in glucose catabolism during growth. These results suggest that the two Synechocystis sp. PCC 6803 NADKs (Sll1415 and Slr0400) have distinct functions in photoheterotrophic cyanobacterial metabolism. |
Databáze: | OpenAIRE |
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