Using Osmotic Stress to Stabilize Mannitol Production in Synechocystis sp. PCC6803

Abstract Background Mannitol is a C(6) polyol that is used in the food and medical sector as a sweetener and antioxidant, respectively. The sustainable production of mannitol, especially via the direct conversion of CO 2 by photosynthetic cyanobacteria, has become increasingly appealing. However, previous work aiming to achieve mannitol production in the marine Synechococcus sp. PCC 7002 via heterologous expression of mannitol-1-phosphate-5-dehydrogenase ( mtlD ) and mannitol-1-phosphatase ( m1p , in short: a ‘mannitol cassette’), proved to be genetically unstable. Results Here, we explore the stabilizing effect that mannitol production may have on cells faced with osmotic stress, in the freshwater cyanobacterium Synechocystis sp. PCC 6803. We first validated that mannitol can function as a compatible solute in Synechocystis sp. PCC 6803, and in derivative strains in which the ability to produce one or both of the native compatible solutes was impaired. Wild type Synechocystis , complemented with a mannitol cassette, indeed showed increased salt tolerance, which was even more evident in Synechocystis strains in which the ability to synthesize the endogenous compatible solutes was impaired. Next we tested the genetic stability of all these strains with respect to their mannitol productivity, with and without salt stress, during prolonged turbidostat cultivations. The obtained results show that mannitol production under salt stress conditions in the Synechocystis strain that cannot synthesize its endogenous compatible solutes is remarkably stable, while the control strain completely loses this ability in only 6 days. DNA sequencing results of the control groups that lost the ability to synthesize mannitol revealed that multiple types of mutation occurred in the mtlD gene that can explain the disruption of mannitol production. Conclusions Mannitol production in freshwater Synechocsytis sp. PCC6803 confers it with increased salt tolerance. Under this strategy, genetically instability which was the major challenge for mannitol production in cyanobacteria is tackled. This paper marks the first report of both stable mannitol production directly from CO 2 in cyanobacteria, and of the utilization of the response to salt stress as a factor that can stabilize production in a cyanobacterial cell factory.

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Using Osmotic Stress to Stabilize Mannitol Production in Synechocystis sp. PCC6803

10.21203/rs.3.rs-17598/v2 ◽

2020 ◽

Author(s):

Wenyang Wu ◽

Wei Du ◽

Ruth Perez Gallego ◽

Klaas J. Hellingwerf ◽

Aniek D. van der Woude ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Osmotic Stress ◽

Compatible Solutes ◽

Direct Conversion ◽

Cell Factory ◽

Medical Sector ◽

Mannitol Production ◽

Synechocystis Sp ◽

Pcc 6803

Abstract Background Mannitol is a C(6) polyol that is used in the food and medical sector as a sweetener and antioxidant, respectively. The sustainable production of mannitol, especially via the direct conversion of CO 2 by photosynthetic cyanobacteria, has become increasingly appealing. However, previous work aiming to achieve mannitol production in the marine Synechococcus sp. PCC 7002 via heterologous expression of mannitol-1-phosphate-5-dehydrogenase ( mtlD ) and mannitol-1-phosphatase ( m1p , in short: a ‘mannitol cassette’), proved to be genetically unstable. Results Here, we explore the stabilizing effect that mannitol production may have on cells faced with osmotic stress, in the freshwater cyanobacterium Synechocystis sp. PCC 6803. We first validated that mannitol can function as a compatible solute in Synechocystis sp. PCC 6803, and in derivative strains in which the ability to produce one or both of the native compatible solutes was impaired. Wild type Synechocystis , complemented with a mannitol cassette, indeed showed increased salt tolerance, which was even more evident in Synechocystis strains in which the ability to synthesize the endogenous compatible solutes was impaired. Next we tested the genetic stability of all these strains with respect to their mannitol productivity, with and without salt stress, during prolonged turbidostat cultivations. The obtained results show that mannitol production under salt stress conditions in the Synechocystis strain that cannot synthesize its endogenous compatible solutes is remarkably stable, while the control strain completely loses this ability in only 6 days. DNA sequencing results of the control groups that lost the ability to synthesize mannitol revealed that multiple types of mutation occurred in the mtlD gene that can explain the disruption of mannitol production. Conclusions Mannitol production in freshwater Synechocsytis sp. PCC6803 confers it with increased salt tolerance. Under this strategy, genetically instability which was the major challenge for mannitol production in cyanobacteria is tackled. This paper marks the first report of utilization of the response to salt stress as a factor that can increase the stability of mannitol production in a cyanobacterial cell factory.

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Using Osmotic Stress to Stabilize Mannitol Production in Synechocystis sp. PCC6803

10.21203/rs.3.rs-17598/v3 ◽

2020 ◽

Author(s):

Wenyang Wu ◽

Wei Du ◽

Ruth Perez Gallego ◽

Klaas J. Hellingwerf ◽

Aniek D. van der Woude ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Osmotic Stress ◽

Compatible Solutes ◽

Direct Conversion ◽

Cell Factory ◽

Medical Sector ◽

Mannitol Production ◽

Synechocystis Sp ◽

Pcc 6803

Abstract Background Mannitol is a C(6) polyol that is used in the food and medical sector as a sweetener and antioxidant, respectively. The sustainable production of mannitol, especially via the direct conversion of CO2 by photosynthetic cyanobacteria, has become increasingly appealing. However, previous work aiming to achieve mannitol production in the marine Synechococcus sp. PCC 7002 via heterologous expression of mannitol-1-phosphate-5-dehydrogenase (mtlD) and mannitol-1-phosphatase (m1p, in short: a ‘mannitol cassette’), proved to be genetically unstable. In this study, we aim to overcome this genetic instability by conceiving a strategy to stabilize mannitol production using Synechocystis sp. PCC 6803 as a model cyanobacterium. Results Here, we explore the stabilizing effect that mannitol production may have on cells faced with osmotic stress, in the freshwater cyanobacterium Synechocystis sp. PCC 6803. We first validated that mannitol can function as a compatible solute in Synechocystis sp. PCC 6803, and in derivative strains in which the ability to produce one or both of the native compatible solutes was impaired. Wild type Synechocystis, complemented with a mannitol cassette, indeed showed increased salt tolerance, which was even more evident in Synechocystis strains in which the ability to synthesize the endogenous compatible solutes was impaired. Next we tested the genetic stability of all these strains with respect to their mannitol productivity, with and without salt stress, during prolonged turbidostat cultivations. The obtained results show that mannitol production under salt stress conditions in the Synechocystis strain that cannot synthesize its endogenous compatible solutes is remarkably stable, while the control strain completely loses this ability in only 6 days. DNA sequencing results of the control groups that lost the ability to synthesize mannitol revealed that multiple types of mutation occurred in the mtlD gene that can explain the disruption of mannitol production. Conclusions Mannitol production in freshwater Synechocsytis sp. PCC6803 confers it with increased salt tolerance. Under this strategy, genetically instability which was the major challenge for mannitol production in cyanobacteria is tackled. This paper marks the first report of utilization of the response to salt stress as a factor that can increase the stability of mannitol production in a cyanobacterial cell factory.

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An orphan two-component response regulator Slr1588 involves salt tolerance by directly regulating synthesis of compatible solutes in photosynthetic Synechocystis sp. PCC 6803

Molecular BioSystems ◽

10.1039/c4mb00095a ◽

2014 ◽

Vol 10 (7) ◽

pp. 1765-1774 ◽

Cited By ~ 16

Author(s):

Lei Chen ◽

Lina Wu ◽

Ye Zhu ◽

Zhongdi Song ◽

Jiangxin Wang ◽

...

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Response Regulator ◽

Compatible Solutes ◽

Two Component ◽

Synechocystis Sp ◽

Pcc 6803

We report here the characterization of a novel orphan response regulator Slr1588 directly involved in the synthesis and transport of compatible solutes against salt stress.

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Integrated proteomic and transcriptomic analysis reveals novel genes and regulatory mechanisms involved in salt stress responses in Synechocystis sp. PCC 6803

Applied Microbiology and Biotechnology ◽

10.1007/s00253-013-5139-8 ◽

2013 ◽

Vol 97 (18) ◽

pp. 8253-8264 ◽

Cited By ~ 47

Author(s):

Jianjun Qiao ◽

Siqiang Huang ◽

Rigen Te ◽

Jiangxin Wang ◽

Lei Chen ◽

...

Keyword(s):

Salt Stress ◽

Stress Responses ◽

Transcriptomic Analysis ◽

Regulatory Mechanisms ◽

Novel Genes ◽

Synechocystis Sp ◽

Pcc 6803

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Effects of long-term ionic and osmotic stress conditions on photosynthesis in the cyanobacterium Synechocystis sp. PCC 6803

Functional Plant Biology ◽

10.1071/fp04219 ◽

2005 ◽

Vol 32 (9) ◽

pp. 807 ◽

Cited By ~ 8

Author(s):

Saowarath Jantaro ◽

Paula Mulo ◽

Tove Jansén ◽

Aran Incharoensakdi ◽

Pirkko Mäenpää

Keyword(s):

Osmotic Stress ◽

Stress Component ◽

D1 Protein ◽

Long Term Effects ◽

High Concentration ◽

High Concentrations ◽

Synechocystis Sp ◽

Halotolerant Cyanobacterium ◽

Pcc 6803

Salinity is considered to be one of the most severe problems in worldwide agricultural production, but the published investigations give contradictory results of the effect of ionic and osmotic stresses on photosynthesis. In the present study, long-term effects of both ionic and osmotic stresses, especially on photosynthesis, were investigated using the moderately halotolerant cyanobacterium Synechocystis sp. PCC 6803. Our results show that the PSII activity and the photosynthetic capacity tolerated NaCl but a high concentration of sorbitol completely inhibited both activities. In line with these results, we show that the amount of the D1 protein of PSII was decreased under severe osmotic stress, whereas the levels of PsaA / B and NdhF3 proteins remained unchanged. However, high concentrations of sorbitol stress led to a drastic decrease of both psbA (encoding D1) and psaA (encoding PsaA) transcripts, suggesting that severe osmotic stress may abolish the tight coordination of transcription and translation normally present in bacteria, at least in the case of the psaA gene. Taken together, our results indicate that the osmotic stress component is more detrimental to photosynthesis than the ionic one and, furthermore, under osmotic stress, the D1 protein appears to be the target of this stress treatment.

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The histidine kinase Hik33 perceives osmotic stress and cold stress in Synechocystis sp. PCC 6803

Molecular Microbiology ◽

10.1046/j.1365-2958.2002.03202.x ◽

2002 ◽

Vol 46 (4) ◽

pp. 905-915 ◽

Cited By ~ 134

Author(s):

Koji Mikami ◽

Yu Kanesaki ◽

Iwane Suzuki ◽

Norio Murata

Keyword(s):

Osmotic Stress ◽

Cold Stress ◽

Histidine Kinase ◽

Synechocystis Sp ◽

Pcc 6803

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The SigB Sigma Factor of the Cyanobacterium Synechocystis sp. PCC 6803 Is Necessary for Adaptation to High-Salt Stress

Photosynthesis. Energy from the Sun ◽

10.1007/978-1-4020-6709-9_291 ◽

2008 ◽

pp. 1351-1353

Author(s):

Maija Pollari ◽

Taina Tyystjärvi

Keyword(s):

Salt Stress ◽

Sigma Factor ◽

High Salt ◽

High Salt Stress ◽

Synechocystis Sp ◽

Pcc 6803

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A PIP-mediated osmotic stress signaling cascade plays a positive role in the salt tolerance of sugarcane

BMC Plant Biology ◽

10.1186/s12870-021-03369-9 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Hanchen Tang ◽

Qing Yu ◽

Zhu Li ◽

Feng Liu ◽

Weihua Su ◽

...

Keyword(s):

Plasma Membrane ◽

Salt Stress ◽

Salt Tolerance ◽

Osmotic Stress ◽

Hybridization Experiment ◽

Signaling Cascade ◽

Stress Signaling ◽

Ion Leakage ◽

Positive Role ◽

Expression Levels

Abstract Background Plasma membrane intrinsic proteins (PIPs) are plant channel proteins involved in water deficit and salinity tolerance. PIPs play a major role in plant cell water balance and responses to salt stress. Although sugarcane is prone to high salt stress, there is no report on PIPs in sugarcane. Results In the present study, eight PIP family genes, termed ScPIP1–1, ScPIP1–2, ScPIP1–3, ScPIP1–4, ScPIP2–1, ScPIP2–2, ScPIP2–4 and ScPIP2–5, were obtained based on the sugarcane transcriptome database. Then, ScPIP2–1 in sugarcane was cloned and characterized. Confocal microscopy observation indicated that ScPIP2–1 was located in the plasma membrane and cytoplasm. A yeast two-hybridization experiment revealed that ScPIP2–1 does not have transcriptional activity. Real time quantitative PCR (RT-qPCR) analysis showed that ScPIP2–1 was mainly expressed in the leaf, root and bud, and its expression levels in both below- and aboveground tissues of ROC22 were up-regulated by abscisic acid (ABA), polyethylene glycol (PEG) 6000 and sodium chloride (NaCl) stresses. The chlorophyll content and ion leakage measurement suggested that ScPIP2–1 played a significant role in salt stress resistance in Nicotiana benthamiana through the transient expression test. Overexpression of ScPIP2–1 in Arabidopsis thaliana proved that this gene enhanced the salt tolerance of transgenic plants at the phenotypic (healthier state, more stable relative water content and longer root length), physiologic (more stable ion leakage, lower malondialdehyde content, higher proline content and superoxide dismutase activity) and molecular levels (higher expression levels of AtKIN2, AtP5CS1, AtP5CS2, AtDREB2, AtRD29A, AtNHX1, AtSOS1 and AtHKT1 genes and a lower expression level of the AtTRX5 gene). Conclusions This study revealed that the ScPIP2–1-mediated osmotic stress signaling cascade played a positive role in plant response to salt stress.

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