Dataset Information

The role of serine/threonine-specific protein kinases in cyanobacteria - SpkB is involved in acclimation to fluctuating conditions in Synechocystis sp. PCC 6803

ABSTRACT: Protein phosphorylation via serine/threonine protein kinases (Spk) is a widespread mechanism to adjust cellular processes toward changing environmental conditions. To study their role(s) in cyanobacteria, we established a collection of 11 completely segregated spk mutants among the 12 annotated Spk’s in the model cyanobacterium Synechocystis sp. PCC 6803. Screening of the mutant collection revealed that especially the mutant defective in SpkB encoded by slr1697 showed clear deviations compared to wild type (WT) regarding carbon metabolism, i.e., a reduced growth rate at low CO2 and in the presence of glucose, different glycogen accumulation patterns, and a higher tolerance to external H2O2 than the WT. The proteome of ∆spkB showed several distinct differences compared to WT, which indicate changes of the cell surface but also metabolic functions. A phospho-proteome analysis revealed decreased phosphorylation of the carboxysome-associated protein CcmM and the regulatory PII protein in the mutant compared to WT, whereas the allophycocyanin alpha subunit was stronger phosphorylated. The decreased phosphorylation of PII was verified in Western-blot experiments, indicating a clearly delayed PII phosphorylation in cells shifted from nitrate-containing to nitrate-free medium. Furthermore, the mutant ∆spkB showed differences in the state transition consistent with the changed phosphorylation of allophycocyanin. Collectively our results indicate that SpkB is an important regulator under different environmental conditions in Synechocystis and seems to interact in the PII phosphorylation and probably with further substrates in a kinase network.

INSTRUMENT(S): Orbitrap Exploris 480

ORGANISM(S): Synechocystis Sp. Pcc 6803

TISSUE(S): Photosynthetic Cell

SUBMITTER: Philipp Spaet

LAB HEAD: Prof. Dr. Martin Hagemann

PROVIDER: PXD040383 | Pride | 2024-01-26

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	20210823_PS_SCy031_R1_phospho_HC_TiO2_1.raw	Raw
	20210823_PS_SCy031_R1_phospho_HC_TiO2_2.raw	Raw
	20210823_PS_SCy031_R1_phospho_HC_TiO2_3.raw	Raw
	20210823_PS_SCy031_R1_phospho_LC24h_TiO2_1.raw	Raw
	20210823_PS_SCy031_R1_phospho_LC24h_TiO2_2.raw	Raw

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The Role of Serine/Threonine-Specific Protein Kinases in Cyanobacteria - SpkB Is Involved in Acclimation to Fluctuating Conditions in Synechocystis sp. PCC 6803.

Barske Thomas T Spät Philipp P Schubert Hendrik H Walke Peter P Maček Boris B Hagemann Martin M

Molecular & cellular proteomics : MCP 20231004 11

Protein phosphorylation via serine/threonine protein kinases (Spk) is a widespread mechanism to adjust cellular processes toward changing environmental conditions. To study their role(s) in cyanobacteria, we investigated a collection of 11 completely segregated spk mutants among the 12 annotated Spks in the model cyanobacterium Synechocystis sp. PCC 6803. Screening of the mutant collection revealed that especially the mutant defective in SpkB encoded by slr1697 showed clear deviations regarding ...[more]

PMID: 37797745

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