Requirement of alkanes for salt tolerance of Cyanobacteria: characterization of alkane synthesis genes from salt-sensitive Synechococcus elongatus
 PCC7942 and salt-tolerant Aphanothece halophytica

β-1,3 xylanase is an important enzyme in the biorefinery process for some algae. The discovery and characterization of new β-1,3 xylanase is a hot research topic. In this paper, a novel β-1,3 xylanase (Xyl88) is revealed from the annotated genome of Flammeovirga pacifica strain WPAGA1. Bioinformatic analysis shows that Xyl88 belongs to the glycoside hydrolase 26 (GH26) with a suspected CBM (carbohydrate-binding module) sequence. The activity of rXyl88 is 75% of the highest enzyme activity (1.5 mol/L NaCl) in 3 mol/L NaCl buffer, which suggests good salt tolerance of rXy188. The optimum reaction temperature in the buffer without NaCl and with 1.5 mol/L NaCl is 45 °C and 55 °C, respectively. Notably, the catalytic efficiency of rXyl88 (kcat/Km) is approximately 20 higher than that of the thermophilic β-1,3 xylanase that has the highest catalytic efficiency. Xyl88 in this study becomes the most efficient enzyme ever found, and it is also the first reported moderately thermophilic and salt-tolerant β-1,3 xylanase. Results of molecular dynamics simulation further prove the excellent thermal stability of Xyl88. Moreover, according to the predicted 3D structure of the Xyl88, the surface of the enzyme is distributed with more negative charges, which is related to its salt tolerance, and significantly more hydrogen bonds and Van der Waals force between the intramolecular residues, which is related to its thermal stability.

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The Characterization of Salt Tolerance in Biomining Microorganisms and the Search for Novel Salt Tolerant Strains

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.71-73.283 ◽

2009 ◽

Vol 71-73 ◽

pp. 283-286 ◽

Cited By ~ 14

Author(s):

Carla M. Zammit ◽

L.A. Mutch ◽

Helen R. Watling ◽

Elizabeth L.J. Watkin

Keyword(s):

Salt Tolerance ◽

Growth Rates ◽

Salt Tolerant ◽

Acidic Media ◽

Comparative Tests ◽

Nacl Tolerance ◽

Oxidation Rates ◽

Australian Wheat ◽

Western Australian

In this study an acidic saline drain in the Western Australian wheat belt was sampled and enriched for salt tolerant chemolithotrophic microorganisms in acidic media containing up to 100 gL-1 NaCl. A mixed consortium was obtained which grows at pH 1.8 and oxidises iron (II) in the presence of up to 30 gL-1 NaCl. In comparative tests (growth rates and iron (II) oxidation rates) it was found that NaCl concentrations >3.5 gL-1 generally cause reduced growth and iron (II) oxidation rates in known biomining organisms. The results help to set a benchmark for NaCl tolerance in known biomining microorganisms and will lead to the generation of a consortium of microorganisms that can oxidise iron (II) effectively in saline process water.

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Characterization of Ethanol Producing Yeasts for Their Efficiency in Ethanol production, Salt Tolerance, and Utilization of Glucose and Xylose

10.21203/rs.2.21857/v1 ◽

2020 ◽

Author(s):

Jarina Joshi ◽

Tribikram Bhattarai ◽

Amar Yadav ◽

Lakshmaiah Sreer

Keyword(s):

Salt Tolerance ◽

Ethanol Production ◽

Yeast Strain ◽

Production Efficiency ◽

Rrna Gene ◽

Mrna Levels ◽

Salt Tolerant ◽

Alcohol Production ◽

Yeast Strains

Abstract Yeasts are the mainstay in ethanol production industry. Search for efficient yeast strains that are salt tolerant and utilize both hexoses (glucose) and pentoses (xylose and arabinose) is important in fermentation industry. In this regard,12 yeast strains, viz., CDBT1-12, were isolated from various sources and characterized. Molecular characterization of the yeast strains was done by sequencing 26S rRNA gene, D1D2 region. Out of 12 isolates, 10 were found to be Saccharomyces cerevisiae , CDBT7 was Wikerhamomyces anomalous , and CDBT8 was Cyberlindnera fabianii . The yeast isolates were characterized in terms of their ethanol production efficiency, salt tolerance and ability to utilize of glucose and xylose. All the strains were found to be good ethanol producers. Yeast strain CDBT2 was found to have tolerance for high salt (up to 15%) and ethanol (up to 16%) concentrations. Yeast strain CDBT7 was found to utilize both glucose and xylose without compromising on ethanol production efficiency. The CDBT7 strain was also salt tolerant (up to15%).Yeast strain CDBT2 when grown in an electrochemical cell with low levels of applied external voltage, alcohol dehydrogenase (ADH1) and pyruvate decarboxylase (PDC1) mRNA levels were increased by 2.78 ± 0.80 and 1.12 ± 0.37 fold, respectively. We believe, the latter observation is novel and it has not been reported previously. It also further supports our previous observation of increase in level of alcohol production by CDBT2 strain in the presence of applied electrical current.

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Isolation and characterization of salt-tolerant bacteria with plant growth-promoting activities from saline agricultural fields of Haryana, India

Journal of Genetic Engineering and Biotechnology ◽

10.1186/s43141-021-00186-3 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Arti Sharma ◽

Kamal Dev ◽

Anuradha Sourirajan ◽

Madhu Choudhary

Keyword(s):

Salt Tolerance ◽

Plant Growth ◽

Phosphate Solubilization ◽

Saline Soil ◽

Plant Growth Promoting Rhizobacteria ◽

Bacterial Isolates ◽

Salt Tolerant ◽

Plant Growth Promoting ◽

Growth Promoting

Abstract Background Soil salinity has been one of the biggest hurdles in achieving better crop yield and quality. Plant growth-promoting rhizobacteria (PGPR) are the symbiotic heterogeneous bacteria that play an important role in the recycling of plant nutrients through phytostimulation and phytoremediation. In this study, bacterial isolates were isolated from salt-polluted soil of Jhajjar and Panipat districts of Haryana, India. The potential salt-tolerant bacteria were screened for their PGPR activities such as phosphate solubilization, hydrogen cyanide (HCN), indole acetic acid (IAA) and ammonia production. The molecular characterization of potent isolates with salt tolerance and PGPR activity was done by 16S rDNA sequencing. Results Eighteen soil samples from saline soils of Haryana state were screened for salt-tolerant bacteria. The bacterial isolates were analyzed for salt tolerance ranging from 2 to 10%. Thirteen isolates were found salt tolerant at varied salt concentrations. Isolates HB6P2 and HB6J2 showed maximum tolerance to salts at 10% followed by HB4A1, HB4N3 and HB8P1. All the salt-tolerant bacterial isolates showed HCN production with maximum production by HB6J2. Phosphate solubilization was demonstrated by three isolates viz., HB4N3, HB6P2 and HB6J2. IAA production was maximum in HB4A1 (15.89) and HB6P2 (14.01) and least in HB4N3 (8.91). Ammonia production was maximum in HB6P2 (12.3) and least in HB8P1 (6.2). Three isolates HB6J2, HB8P1 and HB4N3 with significant salt tolerance, and PGPR ability were identified through sequencing of amplified 16SrRNA gene and were found to be Bacillus paramycoides, Bacillus amyloliquefaciens and Bacillus pumilus, respectively. Conclusions The salt-tolerant plant growth-promoting rhizobacteria (PGPR) isolated from saline soil can be used to overcome the detrimental effects of salt stress on plants, with beneficial effects of physiological functions of plants such as growth and yield, and overcome disease resistance. Therefore, application of microbial inoculants to alleviate stresses and enhance yield in plants could be a low cost and environmental friendly option for the management of saline soil for better crop productivity.

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Transcriptomic Analysis Reveals Salt Tolerance Mechanisms Present in Date-Plum Persimmon Rootstock (Diospyros lotus L.)

Agronomy ◽

10.3390/agronomy10111703 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1703

Author(s):

Francisco Gil-Muñoz ◽

Nicolas Delhomme ◽

Ana Quiñones ◽

Maria del Mar Naval ◽

Maria Luisa Badenes ◽

...

Keyword(s):

Salt Tolerance ◽

Transcriptome Profiling ◽

Rna Seq ◽

Salt Tolerant ◽

Tolerance Mechanisms ◽

Diospyros Lotus ◽

And Control ◽

Different Levels ◽

Tolerance To Salinity

Agriculture needs solutions for adapting crops to increasing salinity globally. Research on physiological and molecular responses activated by salinity is needed to elucidate mechanisms of salinity tolerance. Transcriptome profiling (RNA-Seq) is a powerful tool to study the transcriptomic profile of genotypes under stress conditions. Persimmon species have different levels of tolerance to salinity, this variability may provide knowledge on persimmon species and development of salt--tolerant rootstocks. In this study, we conducted a physiological and transcriptomic profiling of roots and leaves in tolerant and sensitive plants of persimmon rootstock grown under saline and control conditions. Characterization of physiological responses along with gene expression changes in roots and leaves allowed the identification of several salt tolerance mechanisms related to ion transport and thermospermine synthesis. Differences were observed in putative H+/ATPases that allow transmembrane ionic transport and chloride channel protein-like genes. Furthermore, an overexpression of thermospermine synthase found in the roots of tolerant plants may indicate that alterations in root architecture could act as an additional mechanism of response to salt stress. These results indicate that Diospyros lotus L. exhibits genetically-controlled variability for salt tolerance traits which opens potential opportunities for breeding salt-tolerant persimmon rootstocks in a Mediterranean environment challenged by drought and salinity.

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Characterization of Ethanol Producing Yeasts for Their Efficiency in Ethanol production, Salt Tolerance, and Utilization of Glucose and Xylose.

10.21203/rs.2.19816/v1 ◽

2019 ◽

Author(s):

Jarina Joshi ◽

Tribikram Bhattarai ◽

Amar Yadav ◽

Lakshmaiah Sreer

Keyword(s):

Salt Tolerance ◽

Ethanol Production ◽

Yeast Strain ◽

Production Efficiency ◽

Rrna Gene ◽

Mrna Levels ◽

Salt Tolerant ◽

Alcohol Production ◽

Yeast Strains

Abstract Yeast are the mainstay in ethanol production industry. Search for efficient yeast strains that are salt tolerant and utilize both hexoses (glucose) and pentoses (xylose and arabinose) is important in fermentation industry. In this regard,12 yeast strains, viz., CDBT1-12, were isolated from various sources and characterized. Molecular characterization of the yeast strains was done by sequencing 26S rRNA gene, D1D2 region. Out of 12 isolates, 10 were found to be Saccharomyces cerevisiae , CDBT7 was Wikerhamomyces anomalous , and CDBT8 was Cyberlindnera fabianii . The yeast isolates were characterized in terms of their ethanol production efficiency, salt tolerance and ability to utilize of glucose and xylose. All the strains were found to be good ethanol producers. Yeast strain CDBT2 was found to have tolerance for high salt (up to 15%) and ethanol (up to 16%) concentrations. Yeast strain CDBT7 was found to utilize both glucose and xylose without compromising on ethanol production efficiency. The CDBT7 strain was also salt tolerant (up to15%).Yeast strain CDBT2 when grown in an electrochemical cell with low levels of applied external voltage, alcohol dehydrogenase (ADH1) and pyruvate decarboxylase (PDC1) mRNA levels were increased by 2.78 ± 0.80 and 1.12 ± 0.37 fold, respectively. We believe, the latter observation is novel and it has not been reported previously. It also further supports our previous observation of increase in level of alcohol production by CDBT2 strain in the presence of applied electrical current.

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Photosynthetic production of 2-methyl-1-butanol from CO2 in cyanobacterium Synechococcus elongatus PCC7942 and characterization of the native acetohydroxyacid synthase

Energy & Environmental Science ◽

10.1039/c2ee23148d ◽

2012 ◽

Vol 5 (11) ◽

pp. 9574 ◽

Cited By ~ 73

Author(s):

Claire R. Shen ◽

James C. Liao

Keyword(s):

Synechococcus Elongatus ◽

Acetohydroxyacid Synthase ◽

Synechococcus Elongatus Pcc7942 ◽

Photosynthetic Production

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Application of SSR Technique for the Identification of Markers Linked to Salinity Tolerance in Rice

Progressive Agriculture ◽

10.3329/pa.v19i2.16929 ◽

2013 ◽

Vol 19 (2) ◽

pp. 57-65

Author(s):

MH Kabir ◽

MM Islam ◽

SN Begum ◽

AC Manidas

Keyword(s):

Salt Tolerance ◽

Ssr Markers ◽

Salinity Tolerance ◽

Seedling Stage ◽

Phenotypic Screening ◽

Salt Tolerant ◽

Marker Assisted Breeding ◽

Hydroponic System ◽

Rice Landrace ◽

Salt Susceptible

A cross was made between high yielding salt susceptible BINA variety (Binadhan-5) with salt tolerant rice landrace (Harkuch) to identify salt tolerant rice lines. Thirty six F3 rice lines of Binadhan-5 x Harkuch were tested for salinity tolerance at the seedling stage in hydroponic system using nutrient solution. In F3 population, six lines were found as salt tolerant and 10 lines were moderately tolerant based on phenotypic screening at the seedling stage. Twelve SSR markers were used for parental survey and among them three polymorphic SSR markers viz., OSR34, RM443 and RM169 were selected to evaluate 26 F3 rice lines for salt tolerance. With respect to marker OSR34, 15 lines were identified as salt tolerant, 9 lines were susceptible and 2 lines were heterozygous. While RM443 identified 3 tolerant, 14 susceptible and 9 heterozygous rice lines. Eight tolerant, 11 susceptible and 7 heterozygous lines were identified with the marker RM169. Thus the tested markers could be efficiently used for tagging salt tolerant genes in marker-assisted breeding programme.DOI: http://dx.doi.org/10.3329/pa.v19i2.16929 Progress. Agric. 19(2): 57 - 65, 2008

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Genetic Potential for Salt Tolerance During Germination in Lycopersicon Species

HortScience ◽

10.21273/hortsci.32.2.296 ◽

1997 ◽

Vol 32 (2) ◽

pp. 296-300 ◽

Cited By ~ 46

Author(s):

M.R. Foolad ◽

G.Y. Lin

Keyword(s):

Salt Stress ◽

Salt Tolerance ◽

Genotypic Variation ◽

Control Treatment ◽

Molar Ratio ◽

Wild Accession ◽

Salt Tolerant ◽

Plant Introductions ◽

Genetic Potential ◽

Stress Levels

Seed of 42 wild accessions (Plant Introductions) of Lycopersicon pimpinellifolium Jusl., 11 cultigens (cultivated accessions) of L. esculentum Mill., and three control genotypes [LA716 (a salt-tolerant wild accession of L. pennellii Corr.), PI 174263 (a salt-tolerant cultigen), and UCT5 (a salt-sensitive breeding line)] were evaluated for germination in either 0 mm (control) or 100 mm synthetic sea salt (SSS, Na+/Ca2+ molar ratio equal to 5). Germination time increased in response to salt-stress in all genotypes, however, genotypic variation was observed. One accession of L. pimpinellifolium, LA1578, germinated as rapidly as LA716, and both germinated more rapidly than any other genotype under salt-stress. Ten accessions of L. pimpinellifolium germinated more rapidly than PI 174263 and 35 accessions germinated more rapidly than UCT5 under salt-stress. The results indicate a strong genetic potential for salt tolerance during germination within L. pimpinellifolium. Across genotypes, germination under salt-stress was positively correlated (r = 0.62, P < 0.01) with germination in the control treatment. The stability of germination response at diverse salt-stress levels was determined by evaluating germination of a subset of wild, cultivated accessions and the three control genotypes at 75, 150, and 200 mm SSS. Seeds that germinated rapidly at 75 mm also germinated rapidly at 150 mm salt. A strong correlation (r = 0.90, P < 0.01) existed between the speed of germination at these two salt-stress levels. At 200 mm salt, most accessions (76%) did not reach 50% germination by 38 days, demonstrating limited genetic potential within Lycopersicon for salt tolerance during germination at this high salinity.

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Evaluation of salinity tolerance indices in North African barley accessions at reproductive stage

Czech Journal of Genetics and Plant Breeding ◽

10.17221/50/2017-cjgpb ◽

2019 ◽

Vol 55 (No. 2) ◽

pp. 61-69 ◽

Cited By ~ 3

Author(s):

Dorsaf Allel ◽

Anis BenAmar ◽

Mounawer Badri ◽

Chedly Abdelly

Keyword(s):

Salt Tolerance ◽

Grain Yield ◽

Salinity Tolerance ◽

Selection Criteria ◽

Reproductive Stage ◽

Shoot Biomass ◽

Salt Tolerant ◽

North African ◽

Grain Number ◽

Selection Indices

Soil salinity is one of the main factors limiting cereal productivity in worldwide agriculture. Exploitation of natural variation in local barley germplasm is an effective approach to overcome yield losses. Three gene pools of North African Hordeum vulgare L. grown in Tunisia, Algeria and Egypt were evaluated at the reproductive stage under control and saline conditions. Assessment of stress tolerance was monitored using morphological, yield-related traits and phenological parameters of reproductive organs showing significant genetic variation. High heritability and positive relationships were found suggesting that some traits associated with salt tolerance could be used as selection criteria. The phenotypic correlations revealed that vegetative traits including shoot biomass, tiller number and leaf number along with yield-related traits such as spike number, one spike dry weight, grain number/plant and grain number/spike were highly positively correlated with grain yield under saline conditions. Hence, these traits can be used as reliable selection criteria to improve barley grain yield. Keeping a higher shoot biomass and longer heading and maturity periods as well as privileged filling ability might contribute to higher grain production in barley and thus could be potential target traits in barley crop breeding toward improvement of salinity tolerance. Multiple selection indices revealed that salt tolerance trait index provided a better discrimination of barley landraces allowing selection of highly salt-tolerant and highly productive genotypes under severe salinity level. Effective evaluation of salt tolerance requires an integration of selection indices to successfully identify and characterize salt tolerant lines required for valuable exploitation in the management of salt-affected areas.

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