scholarly journals Salt Stress Response of Sulfolobus acidocaldarius Involves Complex Trehalose Metabolism Utilizing a Novel Trehalose-6-Phosphate Synthase (TPS)/Trehalose-6-Phosphate Phosphatase (TPP) Pathway

2020 ◽  
Vol 86 (24) ◽  
Author(s):  
Christina Stracke ◽  
Benjamin H. Meyer ◽  
Anna Hagemann ◽  
Eunhye Jo ◽  
Areum Lee ◽  
...  
Keyword(s):  
Salt Stress ◽  
Stress Response ◽  
Extreme Environments ◽  
Compatible Solutes ◽  
Sulfolobus Acidocaldarius ◽  
Triple Mutant ◽  
Salt Stress Response ◽  
Content Type ◽  
Trehalose Metabolism

ABSTRACT The crenarchaeon Sulfolobus acidocaldarius has been described to synthesize trehalose via the maltooligosyltrehalose synthase (TreY) and maltooligosyltrehalose trehalohydrolase (TreZ) pathway, and the trehalose glycosyltransferring synthase (TreT) pathway has been predicted. Deletion mutant analysis of strains with single and double deletions of ΔtreY and ΔtreT in S. acidocaldarius revealed that in addition to these two pathways, a third, novel trehalose biosynthesis pathway is operative in vivo: the trehalose-6-phosphate (T6P) synthase/T6P phosphatase (TPS/TPP) pathway. In contrast to known TPS proteins, which belong to the GT20 family, the S. acidocaldarius TPS belongs to the GT4 family, establishing a new function within this group of enzymes. This novel GT4-like TPS was found to be present mainly in the Sulfolobales. The ΔtreY ΔtreT Δtps triple mutant of S. acidocaldarius, which lacks the ability to synthesize trehalose, showed no altered phenotype under standard conditions or heat stress but was unable to grow under salt stress. Accordingly, in the wild-type strain, a significant increase of intracellular trehalose formation was observed under salt stress. Quantitative real-time PCR showed a salt stress-mediated induction of all three trehalose-synthesizing pathways. This demonstrates that in Archaea, trehalose plays an essential role for growth under high-salt conditions. IMPORTANCE The metabolism and function of trehalose as a compatible solute in Archaea was not well understood. This combined genetic and enzymatic approach at the interface of microbiology, physiology, and microbial ecology gives important insights into survival under stress, adaptation to extreme environments, and the role of compatible solutes in Archaea. Here, we unraveled the complexity of trehalose metabolism, and we present a comprehensive study on trehalose function in stress response in S. acidocaldarius. This sheds light on the general microbiology and the fascinating metabolic repertoire of Archaea, involving many novel biocatalysts, such as glycosyltransferases, with great potential in biotechnology.

scholarly journals Short-Term Temporal Metabolic Behavior in Halophilic Cyanobacterium Synechococcus sp. Strain PCC 7002 after Salt Shock

Metabolites ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 297 ◽  
Author(s):  
Shimpei Aikawa ◽  
Atsumi Nishida ◽  
Tomohisa Hasunuma ◽  
Jo-Shu Chang ◽  
Akihiko Kondo
Keyword(s):  
Gene Expression ◽  
Mass Spectrometry ◽  
Salt Stress ◽  
Stress Response ◽  
Tricarboxylic Acid Cycle ◽  
Compatible Solutes ◽  
Uptake System ◽  
Salt Stress Response ◽  
Salt Shock ◽  
Synechococcus Sp

In response to salt stress, cyanobacteria increases the gene expression of Na+/H+ antiporter and K+ uptake system proteins and subsequently accumulate compatible solutes. However, alterations in the concentrations of metabolic intermediates functionally related to the early stage of the salt stress response have not been investigated. The halophilic cyanobacterium Synechococcus sp. PCC 7002 was subjected to salt shock with 0.5 and 1 M NaCl, then we performed metabolomics analysis by capillary electrophoresis/mass spectrometry (CE/MS) and gas chromatography/mass spectrometry (GC/MS) after cultivation for 1, 3, 10, and 24 h. Gene expression profiling using a microarray after 1 h of salt shock was also conducted. We observed suppression of the Calvin cycle and activation of glycolysis at both NaCl concentrations. However, there were several differences in the metabolic changes after salt shock following exposure to 0.5 M and 1 M NaCl: (i): the main compatible solute, glucosylglycerol, accumulated quickly at 0.5 M NaCl after 1 h but increased gradually for 10 h at 1 M NaCl; (ii) the oxidative pentose phosphate pathway and the tricarboxylic acid cycle were activated at 0.5 M NaCl; and (iii) the multi-functional compound spermidine greatly accumulated at 1 M NaCl. Our results show that Synechococcus sp. PCC 7002 acclimated to different levels of salt through a salt stress response involving the activation of different metabolic pathways.

scholarly journals Involvement of ethylene receptors in the salt tolerance response of Cucurbita pepo

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Gustavo Cebrián ◽  
Jessica Iglesias-Moya ◽  
Alicia García ◽  
Javier Martínez ◽  
Jonathan Romero ◽  
...  
Keyword(s):  
Salt Stress ◽  
Stress Response ◽  
Salt Tolerance ◽  
Vegetative Growth ◽  
Cucurbita Pepo ◽  
Compatible Solutes ◽  
Negative Regulator ◽  
Ethylene Receptors ◽  
Salt Stress Response ◽  
Tolerance Response

AbstractAbiotic stresses have a negative effect on crop production, affecting both vegetative and reproductive development. Ethylene plays a relevant role in plant response to environmental stresses, but the specific contribution of ethylene biosynthesis and signalling components in the salt stress response differs between Arabidopsis and rice, the two most studied model plants. In this paper, we study the effect of three gain-of-function mutations affecting the ethylene receptors CpETR1B, CpETR1A, and CpETR2B of Cucurbita pepo on salt stress response during germination, seedling establishment, and subsequent vegetative growth of plants. The mutations all reduced ethylene sensitivity, but enhanced salt tolerance, during both germination and vegetative growth, demonstrating that the three ethylene receptors play a positive role in salt tolerance. Under salt stress, etr1b, etr1a, and etr2b germinate earlier than WT, and the root and shoot growth rates of both seedlings and plants were less affected in mutant than in WT. The enhanced salt tolerance response of the etr2b plants was associated with a reduced accumulation of Na+ in shoots and leaves, as well as with a higher accumulation of compatible solutes, including proline and total carbohydrates, and antioxidant compounds, such as anthocyanin. Many membrane monovalent cation transporters, including Na+/H+ and K+/H+ exchangers (NHXs), K+ efflux antiporters (KEAs), high-affinity K+ transporters (HKTs), and K+ uptake transporters (KUPs) were also highly upregulated by salt in etr2b in comparison with WT. In aggregate, these data indicate that the enhanced salt tolerance of the mutant is led by the induction of genes that exclude Na+ in photosynthetic organs, while maintaining K+/Na+ homoeostasis and osmotic adjustment. If the salt response of etr mutants occurs via the ethylene signalling pathway, our data show that ethylene is a negative regulator of salt tolerance during germination and vegetative growth. Nevertheless, the higher upregulation of genes involved in Ca2+ signalling (CpCRCK2A and CpCRCK2B) and ABA biosynthesis (CpNCED3A and CpNCED3B) in etr2b leaves under salt stress likely indicates that the function of ethylene receptors in salt stress response in C. pepo can be mediated by Ca2+ and ABA signalling pathways.

Progress in understanding salt stress response in plants using biotechnological tools

2021 ◽  
Vol 329 ◽  
pp. 180-191
Author(s):  
Ulkar İbrahimova ◽  
Pragati Kumari ◽  
Saurabh Yadav ◽  
Anshu Rastogi ◽  
Michal Antala ◽  
...  
Keyword(s):  
Salt Stress ◽  
Stress Response ◽  
Salt Stress Response

scholarly journals Proteome dynamics and early salt stress response of the photosynthetic organism Chlamydomonas reinhardtii

BMC Genomics ◽  
2012 ◽  
Vol 13 (1) ◽  
pp. 215 ◽  
Author(s):  
Guido Mastrobuoni ◽  
Susann Irgang ◽  
Matthias Pietzke ◽  
Heike E Aßmus ◽  
Markus Wenzel ◽  
...  
Keyword(s):  
Salt Stress ◽  
Stress Response ◽  
Chlamydomonas Reinhardtii ◽  
Salt Stress Response ◽  
Photosynthetic Organism

scholarly journals Interaction of SOS2 with Nucleoside Diphosphate Kinase 2 and Catalases Reveals a Point of Connection between Salt Stress and H2O2 Signaling in Arabidopsis thaliana

2007 ◽  
Vol 27 (22) ◽  
pp. 7771-7780 ◽  
Author(s):  
Paul E. Verslues ◽  
Giorgia Batelli ◽  
Stefania Grillo ◽  
Fernanda Agius ◽  
Yong-Sig Kim ◽  
...  
Keyword(s):  
Salt Stress ◽  
Stress Response ◽  
Stress Responses ◽  
Double Mutant ◽  
Nucleoside Diphosphate Kinase ◽  
Salt Resistance ◽  
Interacting Proteins ◽  
Salt Stress Response ◽  
Oxygen Signaling ◽  
Nucleoside Diphosphate Kinase 2

ABSTRACT SOS2, a class 3 sucrose-nonfermenting 1-related kinase, has emerged as an important mediator of salt stress response and stress signaling through its interactions with proteins involved in membrane transport and in regulation of stress responses. We have identified additional SOS2-interacting proteins that suggest a connection between SOS2 and reactive oxygen signaling. SOS2 was found to interact with the H2O2 signaling protein nucleoside diphosphate kinase 2 (NDPK2) and to inhibit its autophosphorylation activity. A sos2-2 ndpk2 double mutant was more salt sensitive than a sos2-2 single mutant, suggesting that NDPK2 and H2O2 are involved in salt resistance. However, the double mutant did not hyperaccumulate H2O2 in response to salt stress, suggesting that it is altered signaling rather than H2O2 toxicity alone that is responsible for the increased salt sensitivity of the sos2-2 ndpk2 double mutant. SOS2 was also found to interact with catalase 2 (CAT2) and CAT3, further connecting SOS2 to H2O2 metabolism and signaling. The interaction of SOS2 with both NDPK2 and CATs reveals a point of cross talk between salt stress response and other signaling factors including H2O2.

Molecular insights into the role of plant transporters in salt stress response

2021 ◽  
Author(s):  
Ashok Saddhe Ankush ◽  
Ajay Kumar Mishra ◽  
Kumar Kundan
Keyword(s):  
Salt Stress ◽  
Stress Response ◽  
Salt Stress Response
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