Dataset Information

Phosphorus Feast and Famine in Cyanobacteria: Is Luxury Uptake of the Nutrient Just a Consequence of Acclimation to Its Shortage?

ABSTRACT: To cope with fluctuating phosphorus (P) availability, cyanobacteria developed diverse acclimations, including luxury P uptake (LPU)-taking up P in excess of the current metabolic demand. LPU is underexplored, despite its importance for nutrient-driven rearrangements in aquatic ecosystems. We studied the LPU after the refeeding of P-deprived cyanobacterium Nostoc sp. PCC 7118 with inorganic phosphate (Pi), including the kinetics of Pi uptake, turnover of polyphosphate, cell ultrastructure, and gene expression. The P-deprived cells deployed acclimations to P shortage (reduction of photosynthetic apparatus and mobilization of cell P reserves). The P-starved cells capable of LPU exhibited a biphasic kinetic of the Pi uptake and polyphosphate formation. The first (fast) phase (1-2 h after Pi refeeding) occurred independently of light and temperature. It was accompanied by a transient accumulation of polyphosphate, still upregulated genes encoding high-affinity Pi transporters, and an ATP-dependent polyphosphate kinase. During the second (slow) phase, recovery from P starvation was accompanied by the downregulation of these genes. Our study revealed no specific acclimation to ample P conditions in Nostoc sp. PCC 7118. We conclude that the observed LPU phenomenon does not likely result from the activation of a mechanism specific for ample P conditions. On the contrary, it stems from slow disengagement of the low-P responses after the abrupt transition from low-P to ample P conditions.

SUBMITTER: Solovchenko A

PROVIDER: S-EPMC7564538 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Phosphorus Feast and Famine in Cyanobacteria: Is Luxury Uptake of the Nutrient Just a Consequence of Acclimation to Its Shortage?

Solovchenko Alexei A Gorelova Olga O Karpova Olga O Selyakh Irina I Semenova Larisa L Chivkunova Olga O Baulina Olga O Vinogradova Elizaveta E Pugacheva Tatiana T Scherbakov Pavel P Vasilieva Svetlana S Lukyanov Alexandr A Lobakova Elena E

Cells 20200821 9

To cope with fluctuating phosphorus (P) availability, cyanobacteria developed diverse acclimations, including luxury P uptake (LPU)-taking up P in excess of the current metabolic demand. LPU is underexplored, despite its importance for nutrient-driven rearrangements in aquatic ecosystems. We studied the LPU after the refeeding of P-deprived cyanobacterium Nostoc sp. PCC 7118 with inorganic phosphate (Pi), including the kinetics of Pi uptake, turnover of ...[more]

PMID: 32825634

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Dataset Information

Phosphorus Feast and Famine in Cyanobacteria: Is Luxury Uptake of the Nutrient Just a Consequence of Acclimation to Its Shortage?

Publications

Phosphorus Feast and Famine in Cyanobacteria: Is Luxury Uptake of the Nutrient Just a Consequence of Acclimation to Its Shortage?

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