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Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This contribution reports on a study using Purexa™‐MQ multimodal anion‐exchange (AEX) membranes for protein polishing at elevated solution conductivities. Dynamic binding capacities (DBC10) of bovine serum albumin (BSA), human immunoglobulins, and salmon sperm DNA (ss‐DNA) are reported for various salt types, salt concentrations, flowrates, and pH. Using 1 mg/ml BSA, DBC10 values for Purexa™‐MQ were >90 mg/ml at conductivities up to 15 mS/cm. The membranes maintained a high, salt‐tolerant BSA DBC10 of 89.8 ± 2.7 (SD) over the course of 100 bind‐elute cycles. Polishing studies with acidic and basic monoclonal antibodies at >2 kg/L loads showed that Purexa™‐MQ had higher clearance of host cell proteins and aggregate species at high conductivity (13 mS/cm) and in the presence of phosphate than other commercial AEX media. Purexa™‐MQ also had a high ss‐DNA DBC10 of 50 mg/ml at conductivities up to 15 mS/cm, markedly outperforming other commercial products. In addition to the effectiveness of Purexa™‐MQ for protein polishing at elevated solution conductivities, its unusually high binding capacity for ss‐DNA indicates potential applications for plasmid DNA purification. [ABSTRACT FROM AUTHOR]

Organophosphorus compounds (OPCs), including highly toxic nerve agents and pesticides, have been used widely in agricultural and military applications. However, they have aroused widespread concern because they persistently pollute the environment and threaten human life. Organophosphorus acid anhydrolase (OPAA) is a promising enzyme that can detoxify OPCs. Here, a novel OPAA (OPAA114644) was isolated and characterized from deep-sea sediment (−3104 m). It exhibited excellent alkaline stability, and the loss of activity was less than 20% in the pH range 5.0–9.0, even after being incubated for 30 d at 4 °C. It also exhibited high salt tolerance, and its enzymatic activity increased by approximately fourfold in the presence of 20% NaCl (w/v). Additionally, OPAA114644 exhibited high degradation efficiency for soman, dichlorvos, paraoxon, coumaphos, and chlorpyrifos with a concentration of up to 250 mg/L, with the degradation rate being 100%, 100%, 100%, 80% and 51%, respectively, in 20 min under optimal conditions. Notably, OPAA114644 dissolved in different solutions, such as 20% NaCl, 1 mM SDS, 0.05% soap, 10% methanol, and tap water, could efficiently decontaminate the residual paraoxon on the surfaces of glasses, cotton tissues, and apples. These results indicate that OPAA114644 has excellent potential for the biodegradation and bioremediation of OPCs pollution and represents a real application of OPAA in the decontamination and detoxification of foods and clothes, and in the remediation of sites such as floors. Deep-sea sediment might also be an abundant resource for various functional microorganisms and enzymes.

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Saline area may tend to be a productive land; however, many of salt-affected soils have nitrogen limitation and depend on plant-associated diazotrophs as their source of 'new' nitrogen. Herein, a total of 316 salinity tolerant nitrogen-fixing endophytic bacteria were isolated from roots of the halophyte Suaeda sp. sampled from 22 different areas of Iran to prepare the collection of nitrogen-fixing bacterial endophytes and evaluate the plant growth–promoting effect of effective isolates on growth of the halophyte Suaeda maritima. All of the identified nitrogen-fixing endophytes were classified to Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes phylum while we did not detect common nitrogen-fixing endophyte of glycophytes like Azospirillum. The genera Pseudomonas and Microbacterium were both encountered in high abundance in all samples, indicating that they might play an advanced role in the micro-ecosystem of the halophyte Suaeda. In addition, the results also showed that not only soil salinity can affect halophyte endophytic composition but also other factors such as geographical location, plant species, and other soil properties may be involved. Interestingly, only Zhihengliuella halotolerans and Brachybacterium sp. belonging to Actinobacteria could grow in semi-solid N-free (NFb) medium supplemented with 6% NaCl and highly enhanced growth of S. maritima in vitro. Overall, this study offers useful new resources for nitrogen-fixing endophytic bacteria which may be utilized to improve approaches for providing bio-fertilizer useful in saline-based agriculture. [ABSTRACT FROM AUTHOR]

Two novel glycoside hydrolases were cloned from the genomic DNA of alklinphilic bacterium Cellulomonas bogoriensis 69B4T and functionally expressed in Escherichia coli. The two enzymes shared less than 73% of identities with other known glycosidases and belonged to glycoside hydrolase families 5 and 9. Recombinant Cel5A exhibited optimum activity at pH 5.0 and at a temperature of 70 °C, and Cel9A showed optimum activity at pH 7.0 and at a temperature of 60 °C. The two enzymes exhibited activity at alkaline pH 11 and were stable over a wide range of pH. The maximum activities of Cel5A and Cel9A were observed in 0.5 M NaCl and 1 M KCl, respectively. In addition, these two enzymes exhibited excellent halostability with residual activities of more than 70% after pre-incubation for 6 days in 5 M NaCl or 4 M KCl. Substrate specificity analysis revealed that Cel5A and Cel9A specifically cleaved the β-1,4-glycosidic linkage in cellulose with the highest activity on carboxymethyl cellulose sodium (78.3 and 145.3 U/mg, respectively). Cel5A is an endoglucanase, whereas Cel9A exhibits endo and exo activities. As alkali-activated, thermo-tolerant, and salt-tolerant cellulases, Cel5A and Cel9A are promising candidates for further research and industrial applications. [ABSTRACT FROM AUTHOR]

Abstract Background Identification of the quantitative trait locus (QTL) underlying salt tolerance is a prerequisite for marker-assisted selection in the salt-tolerant breeding process. Methods In this study, the recombinant inbred lines derived from the salt-tolerant elite soybean cultivar ‘Jidou 12’ and the salt-sensitive elite cultivar ‘Ji NF 58’ were used to identify the QTL associated with salt tolerance, using both salt tolerance rating (STR) and leaf chlorophyll content (SPAD) as indicators. Results A major salt-tolerant QTL, which was flanked by SSR markers GMABAB and Barcsoyssr_03_1421 on chromosome 3, was identified based on single-marker regression, single trait composite interval mapping, and multiple interval mapping analysis. For STR, the LOD ranged from 19.8 to 20.1; R2 ranged from 44.3 to 44.7%; and the additive effect ranged from 0.876 to 0.885 among the three mapping methods. For SPAD, the LOD ranged from 10.6 to 11.0; R2 ranged from 27.0 to 27.6%; and the additive effect ranged from 1.634 to 1.679 among the three mapping methods. Conclusions In this study, a major QTL conditioning salt tolerance on chromosome 3 was identified. The DNA markers closely associated with the QTLs might be useful in marker-assisted selection for soybean salt tolerance improvement in Huanghuaihai, China.

Background: Salt-tolerant breeding of maize has great significance to the development and utilization of saline–alkaline soil and the maintenance of grain security. Genome-wide association study (GWAS) has been widely used in maize genetics and breeding. Objective: To discover new salt-tolerant genes in maize by association analysis, which can provide technical supports for the innovation and genetic improvement of salt-tolerant germplasm resources in maize. Methods: Totally 150 maize inbred lines were genotyped with a high-density chip. GWAS was carried out to identify the significant single nucleotide polymorphisms (SNPs) which were associated with maize salt tolerance. Totally 34,972 SNPs with high quality and diversity were selected from 56,110 SNP markers, which were distributed on 10 chromosomes of maize. The GLM algorithm in TASSEL5.2 was used to analyze the five traits related to salt tolerance. Results: Using a strict LOD threshold of 4.5, totally 7 SNP loci were identified, which were significantly correlated with plant height change rate and fresh weight change rate. The high density fingerprints of 150 inbred lines were clustered by TASSEL5.2 software to construct genetic clustering map to estimate the genetic distance and the subgroups. The 150 maize inbred lines were divided into two groups: SS group and NSS group, and the SNP loci of the salt-tolerant index showed difference in chromosome distribution. Based on previous studies, we screened 8 candidate genes for salt tolerance in maize and four of them were further validated by real-time quantitative PCR. Conclusion: Totally 7 SNP loci and 8 candidate genes related to salt tolerance in maize were identified, which will be of special value in molecular breeding of salt-tolerant maize. [ABSTRACT FROM AUTHOR]

• Salinity tolerance of five wild grapevine populations was investigated. • Only one wild grapevine population (Sylv5) was able to germinate at 250 mM NaCl. • The ability of seeds to recover their germination greatly varied among populations. • Wild grapevine able to salinity tolerance could be used as rootstock. Wild grapevine [ Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi], belonging to the Vitaceae family, is the ancestor of cultivated grapevine varieties (Vitis vinifera L. subsp. vinifera) and is considered an important Crop Wild Relative (CWR). The response to different levels of saline stress (0, 125, 250, 500 mM NaCl) during the seed germination phase of five populations was evaluated, as well as the potential ability of seeds to recover their germination after the salt exposure. The maximum level of salt in which seeds were able to germinate was 250 mM NaCl, except for the population of Sylv3, which did not germinate at more than 125 mM NaCl. Great inter-populational variability was detected among the other four population ns that germinated at up to 250 mM NaCl, and each of them showed a preferential temperature in this pattern. The ability of seeds to recover their germination after the salt stress greatly varied among populations and as a function of the salinity concentration to which seeds were exposed in the previous phase. No more than ca. 30% of wild grapevine seeds recovered after being sown at 500 mM NaCl, but up to 95% had the ability to recover after 250 mM, showing that seeds of this taxon could tolerate moderate salinity levels in the soil and have successful recovery after rainfalls. Our findings could help in understanding the actual distribution and ecophysiology of the wild grapevine in the Mediterranean area and could be useful in the selection of populations with more salt-tolerant plants that could be used as rootstock for the cultivation of grapevines in areas near to the coastline or salinized soils, where salinity is an important limiting factor. [ABSTRACT FROM AUTHOR]

• Polyanion-π interaction endow the hydrogels with salt-tolerant property. • Gradient hydrogels deserve ionic diode effect and low ionic resistance. • The hydrogel demonstrate anti-swelling and cation selectivity properties. • The gradient polyelectrolyte hydrogel demonstrates a power density of 16.4 W/m2. Harvesting ocean salinity energy has attracted large attentions based on different kinds of asymmetric ionic membranes. Gradient polyelectrolyte hydrogels demonstrated superior power generation capacity due to their abundant charged groups and rectification behaviors. However, they generally suffer from the electrostatic screening and dramatic swelling, leading to unsatisfactory energy conversion performance. Here, an anti-swelling, salt-tolerant gradient polyanion hydrogel is reported for high-efficiency osmotic energy conversion. The gradient polyanion hydrogel is prepared by ultraviolet (UV) induced copolymerization of anionic monomer and aromatic monomer. Benefiting from the mutual electrostatic interaction and π-π conjugation interaction, the gradient polyanion hydrogel presents the outstanding anti-electrostatic screening and anti-swelling performance. As a result, they can maintain excellent cation selectivity and ionic diode effect for providing an ultrahigh power density of 16.4 W/m2 when mixing artificial seawater and river water. This new salt-tolerant gradient polyelectrolyte hydrogel provides a promising way to recover energy from seawater and wastewater. [ABSTRACT FROM AUTHOR]

[Display omitted] • A dendritic Urchin-like MoC/MoS 2 Heterojunction was fabricated. • CC@MoC/MoS 2 -H was synthesized in situ on carbon cloth to create a self-supported electrode. • The electrode demonstrated outstanding HER catalytic activity in both neutral and natural seawater environments. • The dendritic Urchin-like structure exhibited remarkable resistance to high salinity in seawater. The direct electrolysis of abundant near-neutral seawater resources for hydrogen production faces significant challenges due to insufficient catalyst activity and salt toxicity. Herein, we demonstrate a novel dendritic urchin-like MoC/MoS 2 heterojunction in-situ formed on carbon cloth (CC@MoC/MoS 2 -H) through a combination of hydrothermal and high-temperature annealing processes. This unique dendritic urchin-like structure consists of numerous nanorods on carbon cloth, which enhances the catalytic active sites and provides space for efficient bubble release. The resulting CC@MoC/MoS 2 -H exhibits superior catalytic performance, with an overpotential of 91 mV and 136 mV at the current density of 10 mA cm−2 in the 1 M PBS electrolyte and natural seawater, respectively, surpassesing that of most non-noble metal compounds reported previously. Finite element simulations reveal that the urchin-like structure has significantly higher bubble release capacity compared to the randomly stacked structure. Additionally, the urchin-like structure demonstrates substantially greater current density retention under electrolytic conditions designed to simulate salt accumulation, in comparison to the small-size structure. Furthermore, the average H 2 production efficiency of 78,493 μmol h−1 g−1 was evaluated for three consecutive hours using commercial solar panels rated at 2 V on a large-scale electrode assembly from seawater, which is comparable to the present photocatalytic hydrogen production efficiency. This work opens new avenues for the development of catalytic structures compatible with seawater. [ABSTRACT FROM AUTHOR]

In recent years, with the rapid development of industrial revolution and urbanization, the generation and treatment of a large number of salt-containing industrial wastewater has attracted wide attention. A novel salt-tolerant Zobellella denitrificans sp. LX16 with excellent nitrogen removal and biomineralization capabilities was isolated in this experiment. Kinetic experiments were conducted to determine the optimal condition. Under this condition, chemical oxygen demand (COD) can be entirely removed together with ammonia nitrogen, and the removal efficiency of calcium was 88.09%. Growth curves and nitrogen balance tests showed that strain LX16 not only had good HNAD and MICP capabilities, but also had high nitrite reductase and nitrate reductase activities during this process. Three-dimensional fluorescence results reflected that when external carbon sources were lacking or salinity was high, humic acid could effectively enhance the metabolic activity of heterotrophic nitrifying aerobic denitrifying microorganisms through extracellular electron transfer, and the substances produced in the metabolic process could promote biommineralization. Moreover, combined with SEM, SEM-EDS, XRD and FTIR analysis, it is concluded that the microbial surface can provide nucleation sites to form calcium salts, and with the increase of alkalinity to generate Ca 5 (PO 4) 3 OH. The theoretical basis for the use of biological treatment in reverse osmosis wastewater have been proved by this experiment. [Display omitted] • Zobellella denitrificans sp. LX16 with HNAD and MICP capabilities was isolated. • Strain LX16 has salt-tolerance and can adjust itself with the change of salinity. • Kinetic experiments were conducted to determine the optimal condition. • The removal efficiencies of NH 4 +-N, COD and Ca2+ reached 100%, 100% and 88.09%. • High nitrite reductase and nitrate reductase activities of strain LX16 during HNAD. [ABSTRACT FROM AUTHOR]

The abundance of salt-tolerant microorganisms in moromi contributes greatly to the flavor of soy sauce, and Bacillus velezensis CS1.10S, isolated from the traditional Chinese sun-brewed moromi, is one of them. In order to understand the intrinsic mechanism of the fermentation properties of this bacterium, 4211 genes obtained from the sequencing of its genome were annotated, and it was found that genes encoding carbohydrate metabolism and transport accounted for 7.43%. Genes encoding amino acid metabolism and transport accounted for 9.66%, with a total of 284 genes related to amino acid synthesis, and 13 metabolic pathways covering 19 amino acids, which showed that CS1.10S had good carbon and nitrogen metabolism and amino acid production ability. KEGG also annotated three kinds of salt tolerance-related genes, which explained the good performance of CS1.10S in tolerating salt up to 160 g/L. A comparative study of the quality indexes of fermented soy sauce supplemented with CS1.10S revealed that the amino acid nitrogen content of soy sauce supplemented with CS1.10S on the 10th day of fermentation was 7.51% higher than that of the control group, and its total free amino acid content also increased by 42.38%. The contents of reducing sugars and volatile flavor compounds also increased, but the total acid did not change much, indicating that CS1.10S was beneficial to the taste and aroma of soy sauce. The annotation of CS1.10S with brewing-related genes and the corresponding evidence from fermentation tests indicated that CS1.10S has the potential to improve the flavor of soy sauce. [Display omitted] • Bacillus velezensis CS1.10S has abundant brewing-related genes. • KEGG annotation reveals three salt tolerance mechanisms in Bacillus velezensis CS1.10S. • KEGG annotation revealed that CS1.10S has a complete thirteen amino acid metabolic pathway. • Fermentation tests confirmed that CS1.10S is salt tolerant and improves the taste and aroma of soy sauce. • Both genetic annotations and fermentation tests demonstrated the flavor-enhancing potential of B. velezensis. [ABSTRACT FROM AUTHOR]

Salt-tolerant plant growth-promoting rhizobacteria (PGPR) could be an alternative to alleviate salinity problems in rice plants grown in the coastal areas. This study was conducted to isolate and characterize salt-tolerant PGPR and observe their effects on the physiological and biochemical properties of rice plants grown under non-saline and saline glasshouse conditions. Three strains were selected based on their salt-tolerance and plant growth-promoting properties under in vitro saline conditions. These strains were identified as Bacillus tequilensis (UPMRB9), Bacillus aryabhattai (UPMRE6), and Providencia stuartii (UPMRG1) using a 16S rRNA technique. The selected strains were inoculated to three different rice varieties, namely BRRI dhan67 (salt-tolerant), Putra-1 (moderate salt-tolerant), and MR297 (salt-susceptible) under glasshouse conditions. Results showed that the MR297 rice variety inoculated with UPMRB9 produced the highest total chlorophyll content, with an increment of 28%, and lowest electrolyte leakage of 92%. The Putra-1 rice variety also showed a 156% total dry matter increase with the inoculation of this bacterial strain. The highest increase of relative water content and reduction of Na/K ratio were found upon inoculation of UPMRE6 and UPMRB9, respectively. The biggest significant effects of these bacterial inoculations were on relative water content, electrolyte leakage, and the Na/K ratio of the BRRI dhan67 rice variety under saline conditions, suggesting a synergistic effect on the mechanisms of plant salt-tolerance. This study has shown that the application of locally-isolated salt-tolerant PGPR strains could be an effective long-term and sustainable solution for rice cultivation in the coastal areas, which are affected by global climate change.

Bacterial esterases and lipases, especially extremozymes attract increasing attention due to various advantages both in good properties and wide applications. In the present study, a cold-adapted, alkali-stable and highly salt-tolerant esterase (Est700) was cloned from Bacillus licheniformis , expressed and purified with a molecular mass of 25 kDa. The optimal temperature of Est700 was 30 °C, with 35% maximal activity retaining at 0 °C. Its optimal pH was 8.0 and showed high stability at pH 5.0–11.0. Noticeably, Est700 was highly activated by 3.5 M NaCl and the extent of this activation is much stronger than that of currently reported halophilic ones. It was also stable in 5 M NaCl with no activity loss. High salt concentrations changed the secondary structure and folding properties of Est700 with formation of more α-helix and less β-sheet domains. With salt incubation, its melting temperature was estimated to be 57.2 °C, which is 12.8 °C higher than that of native one. Interestingly, Est700 lacks the acidic surface that is considered essential for enzyme stability at high salinity. However, it has a mainly positive surface electrostatic potential, which is probably different from most reported halotolerant esterases. These multiple properties make Est700 a valuable candidate in both basic research and industrial applications. [ABSTRACT FROM AUTHOR]

Saline soils are scattered within multiple inland basins in the semi-arid, rain shadow areas of the South Island, New Zealand. Competing land use activities in agriculture, mining, viticulture and human habitation have led to a strong decline in saline soils to an estimated < 1% of their original distribution. Small areas of ‘new’ (decades old) salinity have arisen at some highly modified sites but these are poorly understood in relation to older saline soils. Recent information from fine-scale geological surveys and geochemical analysis of substrates at two Department of Conservation scientific reserves in Central Otago, with specialist saline flora, is presented in a short synthesis. The goal is to amend existing viewpoints on plant–substrate interactions at what are abandoned gold mine sites. The current surface conditions at Springvale Reserve and Chapman Road Reserve, near Alexandra, which have developed acute salinity during the last 100 years since mining ceased, are outlined. The process of salt accumulation at each site is also clarified and seeks to rectify previous views on local salt source. The new geological data can inform conservation management of the sites, to better address the overall decline of saline habitat for indigenous plant species. A new adaptive management approach is proposed for each reserve that essentially harnesses effects of physical processes, to secure botanical values in the near future. [ABSTRACT FROM AUTHOR]

[Display omitted] • A salt-tolerant polyelectrolyte hydrogel was fabricated. • Mutual interactions of adjacent cations and aromatic rings endow the hydrogel with salt-tolerant properties. • The composite gradient hydrogels present enhanced adsorption and catalytic performance. • The gradient hydrogel matrix demonstrates good stability and reusability used in the saline solutions. The integration of nanostructured materials into hydrogel matrix with chemical gradient holds great promise in gathering the pollutants and enhancing their adsorption or photocatalytic performance. However, the electric potentials rooting in the common gradient polyelectrolyte hydrogel are almost completely shielded by the co-existing counter-ions. In this study, a salt-tolerant gradient polycationic electrolyte hydrogel was fabricated by free radical copolymerization under the induction of unilateral UV illumination, which was used as nanofillers matrix. The cation-π interactions between the adjacent cations and aromatic rings endow the gradient polycationic electrolyte hydrogels deserving the salt-tolerant properties. Thus, the build-in electric potentials are still reactive on enrichment of the anionic heavy metals in highly concentrated salt solutions, altering the defects of the common gradient polyelectrolyte hydrogel. Using Sb(V) adsorption and Cr(VI) photocatalytic reduction as target reactions, the gradient composite hydrogels always display fast and high removal capacities towards these anionic pollutants in the saline solutions of 500 mM, as well as good stability and reusability. This salt-tolerant hydrogel matrix provides a smart material platform with self-driven forces in the fields of pollutant enrichment and removal. [ABSTRACT FROM AUTHOR]

Salinity stress is one of the major abiotic stresses limiting crop production in arid and semi-arid regions. Interest is increasing in the application of PGPRs (plant growth promoting rhizobacteria) to ameliorate stresses such as salinity stress in crop production. The identification of salt-tolerant, or halophilic, PGPRs has the potential to promote saline soil-based agriculture. Halophytes are a useful reservoir of halotolerant bacteria with plant growth-promoting capabilities. Here, we review recent studies on the use of halophilic PGPRs to stimulate plant growth and increase the tolerance of non-halophytic crops to salinity. These studies illustrate that halophilic PGPRs from the rhizosphere of halophytic species can be effective bio-inoculants for promoting the production of non-halophytic species in saline soils. These studies support the viability of bioinoculation with halophilic PGPRs as a strategy for the sustainable enhancement of non-halophytic crop growth. The potential of this strategy is discussed within the context of ensuring sustainable food production for a world with an increasing population and continuing climate change. We also explore future research needs for using halotolerant PGPRs under salinity stress.

Salinity stress is one of the major abiotic stresses limiting crop production in arid and semi-arid regions. Interest is increasing in the application of PGPRs (plant growth promoting rhizobacteria) to ameliorate stresses such as salinity stress in crop production. The identification of salt-tolerant, or halophilic, PGPRs has the potential to promote saline soil-based agriculture. Halophytes are a useful reservoir of halotolerant bacteria with plant growth-promoting capabilities. Here, we review recent studies on the use of halophilic PGPRs to stimulate plant growth and increase the tolerance of non-halophytic crops to salinity. These studies illustrate that halophilic PGPRs from the rhizosphere of halophytic species can be effective bio-inoculants for promoting the production of non-halophytic species in saline soils. These studies support the viability of bioinoculation with halophilic PGPRs as a strategy for the sustainable enhancement of non-halophytic crop growth. The potential of this strategy is discussed within the context of ensuring sustainable food production for a world with an increasing population and continuing climate change. We also explore future research needs for using halotolerant PGPRs under salinity stress. [ABSTRACT FROM AUTHOR]

Consisted of anaerobic (ANA), anoxic-1 (AN1), aerobic-1 (AE1), anoxic-2 (AN2), aerobic-2 (AE2) reactors and sediment tank, the two-staged A/O process was applied for depth treatment of electroplating tail wastewater with high electrical conductivity and large amounts of ammonia nitrogen. It was found that the NH 4 + -N and COD removal efficiencies reached 97.11% and 83.00%, respectively. Besides, the short-term salinity shock of the control, AE1 and AE2 indicated that AE1 and AE2 have better resistance to high salinity when the concentration of NaCl ranged from 1 to 10 g/L. Meanwhile, it was found through high-throughput sequencing that bacteria genus Nitrosomonas , Nitrospira and Thauera , which are capable of nitrogen removal, were enriched in the two-staged A/O process. Moreover, both salt-tolerant bacteria and halophili bacteria were also found in the combined process. Therefore, microbial community within the two-staged A/O process could be acclimated to high electrical conductivity, and adapted for electroplating tail wastewater treatment. [ABSTRACT FROM AUTHOR]

A GH11 xylanase gene ( xyn11-1 ) cloned from saline-alkali soil was successfully expressed in Pichia pastoris GS115. The purified recombinant Xyn11-1 showed its maximal activity at pH 6.0, and retained more than 60.4% of activity at pH 10.0, with good pH stability. Its optimal temperature was 50 °C and it was stable after incubation for 1 h at 30 °C. Furthermore, Xyn11-1 was highly salt-tolerant, retaining more than 77.4% of activity in the presence of 0.25–4 M NaCl and displaying more than 47.2% relative activity after being incubated in the presence of 5 M NaCl at 37 °C for 10 min. In addition, 5 mM β-Mercaptoethanol, Cu 2+ , Co 2+ , and Mn 2+ increased the xylanase activity by 22.3%, 8.8%, 7.1%, and 4.4%, respectively. Significantly, 93.4% and 59.8% of the optimal activity was retained in the presence of 2% and 10% (v/v) ethanol, respectively. Under optimal conditions, the K m, V max, and K cat value of Xyn11-1 for beechwood xylan were 3.7 mg ml −1 , 101.0 μmol min −1 mg −1 and 42.1 s −1 , respectively. Xyn11-1 is a strict endo-β-1,4-xylanase, its main enzymatic products being xylotetraose and xylopentaose. Xyn11-1 is the first reported GH11 xylanase isolated from saline-alkali soil, and has excellent tolerance of high pH, high salt concentrations and ethanol, which indicates its great potential for basic research and industrial applications. [ABSTRACT FROM AUTHOR]

In order to identify fish enzymes displaying novel biochemical properties, we choose the common smooth-hound ( Mustelus mustelus ) as a starting biological material to characterize the digestive lipid hydrolyzing enzyme. A smooth-hound digestive lipase (SmDL) was purified from a delipidated pancreatic powder. The SmDL molecular weight was around 50 kDa. Specific activities of 2200 and 500 U/mg were measured at pH 9 and 40 °C using tributyrin and olive oil emulsion as substrates, respectively. Unlike known mammal pancreatic lipases, the SmDL was stable at 50 °C and it retained 90% of its initial activity after 15 min of incubation at 60 °C. Interestingly, bile salts act as an activator of the SmDL. It’s worth to notice that the SmDL was also salt-tolerant since it was active in the presence of high salt concentrations reaching 0.8 M. Fatty acid (FA) analysis of oil from the smooth-hound viscera showed a dominance of unsaturated ones (UFAs). Interestingly, the major n-3 fatty acids were DHA and EPA with contents of 18.07% and 6.14%, respectively. In vitro digestibility model showed that the smooth hound oil was efficiently hydrolyzed by pancreatic lipases, which suggests the higher assimilation of fish oils by consumers. [ABSTRACT FROM AUTHOR]

An alginate lyase producing bacterial strain, Cobetia sp. WG-007, was isolated and identified from rotting seaweed. The alginate lyase, Aly-W02, was purified by procedures of ultrafiltration, Q-Sepharose Fast Flow, Phenyl Sepharose 6 Fast Flow, and Superdex-G100 with specific activity of 21,285.5 U/mg. Aly-W02 had an apparent molecular mass of 35 kDa. It exhibited maximum activity at 45 °C in 50 mM sodium phosphate buffer (pH 8.5). This alginate lyase was stable in the pH range of 6.0-8.5. Among the tested metal ions, the addition of K+, Na+, and Mg2+ ions can enhance the enzyme activities, while Ba2+, Ni+, Cu2+, Mn2+, Zn2+, Ag+, and ethylenediaminetetraacetic acid decreased the activities. It displayed high salt-tolerant ability; 0.8 M NaCl or 1.5 M KCl significantly enhanced the enzyme activity. Furthermore, Aly-W02 mainly released disaccharide, trisaccharide, and tetrasaccharid from alginate. It showed potential in producing low molecular weight alginate oligosaccharides. [ABSTRACT FROM AUTHOR]

A novel multi-domain high molecular xylanase coding gene (xynSL3) was cloned from Alkalibacterium sp. SL3, an alkaliphilic bacterial strain isolated from the sediment of soda lake Dabusu. The deduced XynSL3 is composed of a putative signal peptide, three tandem domains of carbohydrate binding module (CBM) family 22, a catalytic domain of glycosyl hydrolase (GH) family 10 and a domain of CBM9. XynSL3 shares the highest identity of 66% to a hypothetical protein from Alkalibacterium sp. AK22 and has low identities (33-45%) with other functionally characterized xylanases. The gene xynSL3 was expressed heterologously in Escherichia coli and the recombinant enzyme demonstrated some particular characteristics. Purified recombinant XynSL3 (rXynSL3) was highly active and stable over the neutral and alkaline pH ranges from 7.0 to 12.0, with maximum activity at pH 9.0 and around 45% activity at pH 12.0. It had an apparent temperature optimum of 55°C and was stable at 50°C. The rXynSL3 was highly halotolerant, retaining more than 60% activity with 3 M NaCl and was stable at up to a 4 M concentration of NaCl. The hydrolysis products of rXynSL3 from corncob xylan were mainly xylobiose and xylotetraose. The activity of rXynSL3 was enhanced by Ca2+ and it has strong resistance to sodium dodecyl sulfate (SDS). This multi-domain, alkaline and salt-tolerant enzyme has great potential for basic research and industrial applications such as the biobleaching of paper pulp and production of xylo-oligosaccharides (XOS). [ABSTRACT FROM AUTHOR]

An aminopeptidase was isolated from the marine Bacillus licheniformis SWJS33 (BLAP) and purified. According to the tandem mass spectrometry, the enzyme displayed 11% amino acid identity with the aminopeptidase from Bacillus (gi|496687392). BLAP exhibited maximum activity at 60 °C and pH 8.0–8.5 and had a molecular mass of 100 kDa. The presence of NaCl enabled 50% improvement of enzyme activity with 10–15% NaCl being the best. The observed inactivation by EDTA and bestatin and activation by Co 2+ and Ag + indicated that the obtained enzyme was a metalloaminopeptidase. Such an aminopeptidase could further improve the hydrolysis degree of soy protein isolate hydrolysates catalyzed by papain, Alcalase 2.4 L or Flavourzyme 500MG from 8.5%, 9.5% or 14.4–18.8%, 18.7% or 20.1%, respectively, while decreasing the bitter intensity score of the SPI hydrolysates catalyzed by Alcalase 2.4 L from 3.6 to 0.4. [ABSTRACT FROM AUTHOR]

Esterases are widely used in different industries. Here, a novel esterase, Esth, with low identity with previously reported esterases, was identified and characterized. The results showed that Esth was a cold-adapted esterase and retained 50% of its maximum activity at 0 °C. Besides, Esth showed great activity and stability in high concentrations of NaCl. When treated with some organic solvents, detergents and metal ions, Esth showed high activity as well. The kcat/Km value of Esth was 29.5 s −1 mM −1 , suggesting that it has higher catalytic efficiency than all the previously reported esterases from the same family, lipolytic enzyme family VI. The structural modeling showed that changing Ala129 into Gly would form a new hydrogen bond between ser125 and Gly129 and make theα-helix longer, which might influence on the thermostability of enzymes (Kumar, 2000). To confirm this, the mutant Esth A129G was obtained by site-directed mutagenesis. The result indicated that Esth A129G retained over 70% of the activity versus 12% for Esth after incubation at 55 °C for 120 min, showed a nearly six fold increase when compared with wild type. Overall, Esth shows a potential application prospect in extreme conditions and the mutation research can provide some structural information about thermostable enzymes. [ABSTRACT FROM AUTHOR]

Low levels of artemisinin in Artemisia annua is posing serious limitation in sustainable supply of this drug and ultimately affecting global struggle to cure malaria. The present study explores new ways for higher artemisinin production through generating somaclonal variant tolerant against salt stress. Here, through gamma-rays irradiation a total of 13 somaclonal variants (ASV1 to ASV13) were identified. They were characterized on the basis of morphological traits and further molecular characterization was carried out through RAPD analysis. Dendrogram, constructed on the basis of RAPD scores, showed six major clusters in which ASV12 was most distant from control to fallen alone in last cluster. Based on 16 metric traits examined among 13 somaclonal variants and wild type, correlation analysis was carried out. In addition, principle component analysis was conducted to attest the results. All statistical analysis suggested ASV12 as stable salt tolerant somaclonal variant of A. annua. ASV12 had higher artemisinin content as compared to wild type and under salt stress; expression of key artemisinin biosynthetic genes ( ADS, CYP71AV1, DBR2 and ALDH1) was more in ASV12 as compared to wild type. Further SCAR marker (570 bp) linked with high artemisinin was developed and further tested on the low and high artemisinin yielding lines, F and F progenies. A single band was amplified in ASV12 and all high artemisinin-yielding plants. The study provides ample possibility of cultivation of ASV12 variant of A. annua on saline soil for dual benefit: high artemisinin production and utilization of waste saline land. [ABSTRACT FROM AUTHOR]

Desert plants exposed to salt stress undergo changes in extreme environment. The ability of plants to detoxify radicals under conditions of salt stress is probably the most critical requirement. Many salt-tolerant species accumulate methylated metabolites, which play crucial dual roles as radical scavengers. Their synthesis is correlated with stress-induced enhancement of photorespiration. It is a temporary and effective desert plant replantation method for defeating the desertification that the desert plant was irrigated by saline water. Apart from plant characteristics, soil composition and drainage characteristics also need to be taken into consideration as they can influence the severity of plant damage by saline irrigation water. This study aims to claim the salt-tolerant and suitable salt concentration of Haloxylon ammodendron through saline water irrigation experiment. The results indicated that the linear relationship between the physiological indices (such as the chlorophyll, proline, and MDA content and membrane permeability) with the salt content of soil. According to modeling of the experimental results, the best conditions of salt content and the salt threshold for growth indices of Haloxylon ammodendron is 4.65 ± 0.23 g /100 g. [ABSTRACT FROM AUTHOR]

Two-stage aerobic coupled process consisted of anoxic, aerobic-1 with low DO and aerobic-2 with high DO (short for “A-LO-HO” process), was applied for post-treatment of poultry manure wastewater, which suffered by high ammonia nitrogen and high salinity. Outstanding NH 4 + -N removal efficiency of 99.5% was obtained, and the COD removal efficiency was about 75%, even under the severe stress. Multiple molecular technologies, include DGGE, real time PCR and high-throughput sequencing were applied to reveal the microbial community of the sludge. The reasonable distribution of the dominant bacteria Nitrosomonas and Nitrobacter would explain the synergistic effect of the partial nitrification in “A-LO” section and the completed nitrification in “HO” section. The microbial community and EPS analysis further confirmed the outstanding nitrifying ability, good salt-tolerant ability, and unaffected sedimentation property of the sludge with particular enhanced features which is acclimated for long time by the targeted coupled process and suitable for this kind of wastewater treatment. [ABSTRACT FROM AUTHOR]

Two new alginate lyase genes, oalY1 and oalY2, have been cloned from the newly isolated marine bacterium Halomonas sp. QY114 and expressed in Escherichia coli. The deduced alginate lyases, OalY1 and OalY2, belonged to polysaccharide lyase (PL) family 17 and showed less than 45% amino acid identity with all of the characterized oligoalginate lyases. OalY1 and OalY2 exhibited the highest activities at 45°C and 50°C, respectively. Both of them showed more than 50% of the highest activity at 60°C, and 20% at 80°C. In addition, they were salt-dependent and salt-tolerant since both of them showed the highest activity in the presence of 0.5 M NaCl and preserved 63% and 68% of activity in the presence of 3 M NaCl. Significantly, OalY1 and OalY2 could degrade both polyM and polyG blocks into alginate monosaccharides in an exo-lytic type, indicating that they are bifunctional alginate lyases. In conclusion, our study indicated that OalY1 and OalY2 are good candidates for alginate saccharification application, and the salt-tolerance may present an exciting new concept for biofuel production from native brown seaweeds. [ABSTRACT FROM AUTHOR]

Isolation, identification and characterization of a salt-tolerant yeast capable of degrading and detoxifying azo dyes were investigated in this study. Possible degradation pathway of Acid Scarlet 3R was proposed through analyzing metabolic intermediates using UV–Vis and HPLC-MS methods. Furthermore, the Microtox test was performed to evaluate the acute toxicity of the dye before and after biodegradation. The results showed that a salt-tolerant yeast named TLHS-SF1 was isolated and identified as Scheffersomyces spartinae basing on 26S rDNA analysis. The optimal decolorization and growth parameters were: sucrose 2 g L −1 , (NH 4 ) 2 SO 4 0.6 g L −1 , yeast extract 0.08 g L −1 , NaCl ⩽ 30 g L −1 , 160 r min −1 , 30 °C and pH 5.0–6.0. More than 90% of 80 mg L −1 3R could be decolorized within 16 h under the optimal conditions. 3R was possibly degraded successively through azo-reduction, deamination and desulfonation pathways, and its acute toxicity obviously decreased by strain TLHS-SF1. [ABSTRACT FROM AUTHOR]

We have previously reported a non-processive endo-type chitinase, ChiA, from a newly isolated marine psychrophilic bacterium, Pseudoalteromonas sp. DL-6. In this study, a processive exo-type chitinase, ChiC, was cloned from the same bacterium and characterized in detail. ChiC could hydrolyze crystalline chitin into (GlcNAc) as the only observed product. It exhibited high catalytic activity even at low temperatures, e.g. close to 0 °C, or in the presence of 5 M NaCl, suggesting that ChiC was a cold-adapted and highly salt-tolerant chitinase. ChiC could also hydrolyze other substrates, including chitosan and Avicel, indicating its broad substrate specificity. Sequence features indicated that ChiC was a multi-domain protein having a deep substrate-binding groove that was regarded as characteristic of processive exo-chitinases. Enzymatic hydrolysis of chitin by ChiC could be remarkably boosted in the presence of ChiA, suggesting the synergy of ChiC and ChiA. This work provided a new evidence to prove that marine psychrophilic bacteria utilized a synergistic enzyme system to degrade recalcitrant chitin. [ABSTRACT FROM AUTHOR]

[Display omitted] • Salt-tolerant polymer with high charge density was prepared by chitosan etherification. • Good salt tolerance originates from H-bond hydration against the polyelectrolyte effect. • Excellent dye flocculation in a high-salinity system was obtained by the resultant polymer. • Highly saline effluent flocculation-reuse can be achieved via salt-tolerant polymer. The textile industry is required to execute water conservation and contamination management techniques owing to increasingly serious water scarcity and pollution. Herein, a novel salt-tolerant chitosan-based flocculant (CT-CTA-BGE3) with high charge density was synthesized through chitosan (CT) etherification with 2,3-epoxypropyl trimethylammonium chloride (CTA) and butyl glycidyl ether (BGE). The H-bond hydration effect between BGE segments and water molecules weakens the salt-induced polyelectrolyte effect, allowing CT-CTA-BGE3 to chains keep an extended conformation in high-salty aqueous solution and thus endowing excellent salt-tolerant properties. Meanwhile, the incorporation of CTA segments offers a high positive charge on the flocculant surface. Thus, the beneficial effect of satisfying color removal was obtained by CT-CTA-BGE3 in a highly saline system because it would render the more exposed active sites with strong positive charges along stretched polymer chains. The outstanding flocculability of CT-CTA-BGE3 (3054 mg/g) for the reactive brilliant red 2 (a widely commercial grade dye) could be obtained within 5 min (pH = 6). As expected, because the CT-CTA-BGE3 impurities can be reduced in reclaimed water via the pH-mediated hydrophilicity-hydrophobicity switch of polymer, the obtained clarified saline wastewater after flocculation can be recycled in a new dyeing bath without sacrificing fabric quality (ΔE*less than1), and over 88 % of NaCl can be regenerated for each cycle. This work develops an alternative strategy for the fabrication of salt-tolerant flocculants through enhancing H-bond hydration, revealing the promising application prospects in treating and recycling highly saline textile wastewater. [ABSTRACT FROM AUTHOR]

A low-temperature-active and salt-tolerant β-mannanase produced by a novel mannanase-producer, Enterobacter sp. strain N18, was isolated, purified and then evaluated for its potential application as a gel-breaker in relation to viscosity reduction of guar-based hydraulic fracturing fluids used in oil field. The enzyme could lower the viscosity of guar gum solution by more than 95% within 10 min. The purified β-mannanase with molecular mass of 90 kDa displayed high activity in a broad range of pH and temperature: more than 70% of activity was retained in the pH range of 3.0–8.0 with the optimal pH 7.5, about 50% activity at 20°C with the optimal temperature 50°C. Furthermore, the enzyme retained >70% activity in the presence of 0.5–4.0 M NaCl. These properties implied that the enzyme from strain N18 had potential for serving as a gel-breaker for low temperature oil wells and other industrial fields, where chemical gel breakers were inactive due to low temperature. [ABSTRACT FROM AUTHOR]

Background: In recent years, cold-active esterases have received increased attention due to their attractive properties for some industrial applications such as high catalytic activity at low temperatures. Results: An esterase-encoding gene (estS, 909 bp) from Serratia sp. was identified, cloned and expressed in Escherichia coli DE3 (BL21). The estS encoded a protein (EstS) of 302 amino acids with a predicted molecular weight of 32.5 kDa. It showed the highest activity at 10 °C and pH 8.5. EstS was cold active and retained ~92 % of its original activity at 0 °C. Thermal inactivation analysis showed that the T1/2 value of EstS was 50 min at 50 °C (residual activity 41.23 %) after 1 h incubation. EstS is also quite stable in high salt conditions and displayed better catalytic activity in the presence of 4 M NaCl. To improve the thermo-stability of EstS, variants of estS gene were created by error-prone PCR. A mutant 1-D5 (A43V, R116W, D147N) that showed higher thermo-stability than its wild type predecessor was selected. 1-D5 showed enhanced T1/2 of 70 min at 50 °C and retained 63.29 % of activity after incubation at 50 °C for 60 min, which were about 22 % higher than the wild type (WT). CD spectrum showed that the secondary structure of WT and 1-D5 are more or less similar, but an increase in β-sheets was recorded, which enhanced the thermostability of mutant protein. Conclusion: EstS was a novel cold-active and salt-tolerant esterase and half-life of mutant 1-D5 was enhanced by 1.4 times compared with WT. The features of EstS are interesting and can be exploited for commercial applications. The results have also provided useful information about the structure and function of Est protein. [ABSTRACT FROM AUTHOR]

Proteases produced by Aspergillus niger LBA 02 under solid state fermentation using different agroindustrial wastes had their enzyme activities tested in the presence of organic solvents, NaCl, surfactants and oxidizing agents. The results showed that according to the fermentation substrate, the microorganism was able to secrete proteases with different biochemical characteristics. When wheat bran was used as the substrate, the proteases showed the highest relative activity in 50% (v/v) petroleum ether, reaching 114.3%, while the proteases produced in soybean meal and cottonseed meal presented 94.7% and 106.1%, respectively. These enzymes also presented high relative activity values in 50% (v/v) chloroform, retaining up to 85% of their initial protease activities after 3 h at 37 °C. When surfactants and oxidizing agents were tested, the proteases produced in soybean meal proved to have remarkable and the highest activity followed by the proteases produced in wheat bran and cottonseed meal. Since the protease produced in wheat bran showed considerable tolerance at high concentrations of NaCl, with relative activity of 61.1% at 15% NaCl (w/v), while the proteases produced in soybean meal and cottonseed meal retained 48.7% and 46.3% of their initial activities, respectively. This work provides an interesting approach about the modulation of biochemical properties of enzymes in response to different substrates, what can be used for obtaining proteases with specific applications. [ABSTRACT FROM AUTHOR]

Seed germination is important for early plant morphogenesis as well as abiotic stress tolerance, and is mainly controlled by the phytohormones abscisic acid (ABA) and gibberellic acid (GA). Our previous studies identified a salt-tolerant tomato cultivar, LA2711, which is also a fast-germinating genotype, compared to its salt-sensitive counterpart, ZS-5. In an effort to further clarify the mechanism underlying this phenomenon, we compared the dynamic levels of ABA and GA 4 , the transcript abundance of genes involved in their biosynthesis and catabolism as well as signal transduction between the two cultivars. In addition, we tested seed germination sensitivity to ABA and GAs. Our results revealed that insensitivity of seed germination to exogenous ABA and low ABA content in seeds are the physiological mechanisms conferring faster germination rates of LA2711 seeds. SlCYP707A2 , which encodes an ABA catabolic enzyme, may play a decisive role in the fast germination rate of LA2711, as it showed a significantly higher level of expression in LA2711 than ZS-5 at most time points tested during germination. The current results will enable us to gain insight into the mechanism(s) regarding seed germination of tomato and the role of fast germination in stress tolerance. [ABSTRACT FROM AUTHOR]

A salt-tolerant esterase, designated H9Est, was identified from a metagenomic library of the Karuola glacier. H9Est gene comprised 1071 bp and encoded a polypeptide of 357 amino acids with a molecular mass of 40 kDa. Sequence analysis revealed that H9Est belonged to the family IV of bacterial lypolitic enzyme. H9Est was overexpressed in Escherichia coli and the purified enzyme showed hydrolytic activity towards p-nitrophenyl esters with carbon chain from 2 to 8. The optimal esterase activity was at 40°C and pH 8.0 and the enzyme retained its activity towards some miscible organic solvents such as polyethylene glycol. A three-dimensional model of H9Est revealed that S200, D294, and H324 formed the H9Est catalytic triad. Circular Dichroism spectra and molecular dynamic simulation indicated that the esterase had a wide denaturation temperature range and flexible loops that would be beneficial for H9Est performance at low temperatures while retaining heat-resistant features. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:890-899, 2015 [ABSTRACT FROM AUTHOR]

Background: Soil salinity is a significant factor that impairs plant growth and agricultural productivity, and numerous efforts are underway to enhance salt tolerance of economically important plants. Populus species are widely cultivated for diverse uses. Especially, they grow in different habitats, from salty soil to mesophytic environment, and are therefore used as a model genus for elucidating physiological and molecular mechanisms of stress tolerance in woody plants. Description: The Salinity Tolerant Poplar Database (STPD) is an integrative database for salt-tolerant poplar genome biology. Currently the STPD contains Populus euphratica genome and its related genetic resources. P. euphratica, with a preference of the salty habitats, has become a valuable genetic resource for the exploitation of tolerance characteristics in trees. This database contains curated data including genomic sequence, genes and gene functional information, non-coding RNA sequences, transposable elements, simple sequence repeats and single nucleotide polymorphisms information of P. euphratica, gene expression data between P. euphratica and Populus tomentosa, and whole-genome alignments between Populus trichocarpa, P. euphratica and Salix suchowensis. The STPD provides useful searching and data mining tools, including GBrowse genome browser, BLAST servers and genome alignments viewer, which can be used to browse genome regions, identify similar sequences and visualize genome alignments. Datasets within the STPD can also be downloaded to perform local searches. Conclusions: A new Salinity Tolerant Poplar Database has been developed to assist studies of salt tolerance in trees and poplar genomics. The database will be continuously updated to incorporate new genome-wide data of related poplar species. This database will serve as an infrastructure for researches on the molecular function of genes, comparative genomics, and evolution in closely related species as well as promote advances in molecular breeding within Populus. The STPD can be accessed at http://me.lzu.edu.cn/stpd/. [ABSTRACT FROM AUTHOR]

Salinity is one of the most brutal environmental factors limiting the productivity of crop plants because most of the crop plants are sensitive to salinity caused by high concentrations of salts in the soil, and the area of land affected by it is increasing day by day. For all important crops, average yields are only a fraction – somewhere between 20% and 50% of record yields; these losses are mostly due to drought and high soil salinity, environmental conditions which will worsen in many regions because of global climate change. A wide range of adaptations and mitigation strategies are required to cope with such impacts. Efficient resource management and crop/livestock improvement for evolving better breeds can help to overcome salinity stress. However, such strategies being long drawn and cost intensive, there is a need to develop simple and low cost biological methods for salinity stress management, which can be used on short term basis. Microorganisms could play a significant role in this respect, if we exploit their unique properties such as tolerance to saline conditions, genetic diversity, synthesis of compatible solutes, production of plant growth promoting hormones, bio-control potential, and their interaction with crop plants. [ABSTRACT FROM AUTHOR]

Introduction: Salinity is a complex environmental stress that affects the growth and production of rice worldwide. But there are some rice landraces in coastal regions that can survive in presence of highly saline conditions. An understanding of the molecular attributes contributing to the salinity tolerance of these genotypes is important for developing salt-tolerant high yielding modern genotypes to ensure food security. Therefore, we investigated the role and functional differences of two K + salt-responsive transporters. These are OsTPKa or Vacuolar two-pore potassium channel and OsHAK&#95;like or a hypothetical protein of the HAK family. These transporters were selected from previously identified QTLs from the tolerant rice landrace genotype (Horkuch) and sensitive genotype (IR29)., Methods: In silico comparative sequence analysis of the promoter sequences of two these genes between Horkuch and IR29 was done. Real-Time expression of the selected genes in leaves and roots of IR29 (salt-sensitive), I-14 and I-71 (Recombinant Inbred Lines of IR29(♀)× Horkuch), Horkuch and Pokkali (salt-tolerant) under salt-stress at different time points was analyzed. For further insight, OsTPKa and OsHAK&#95;like were chosen for loss-of-function genomic analysis in Horkuch using the CRISPR/Cas9 tool. Furthermore, OsTPKa was chosen for cloning into a sensitive variety by Gateway technology to observe the effect of gain-of-function., Results: The promoter sequences of the OsTPKa and OsHAK&#95;like genes showed some significant differences in promoter sequences which may give a survival advantage to Horkuch under salt-stress. These two genes were also found to be overexpressed in tolerant varieties (Horkuch and Pokkali). Moreover, a coordinated expression pattern between these two genes was observed in tolerant Horkuch under salt-stress. Independently transformed plants where the expression of these genes was significantly lowered, performed poorly in physiological tests for salinity tolerance. On the other hand, positively transformed T 0 plants with the OsTPKa gene from Horkuch consistently showed growth advantage under both control and salt stress., Discussion: The poor performance of the transgenic plants with the down-regulated genes OsTPKa and OsHAK&#95;like under salt stress supports the assumption that OsTPKa and OsHAK&#95;like play important roles in defending the rice landrace Horkuch against salt stress, minimizing salt injury, and maintaining plant growth. Moreover, the growth advantage provided by overexpression of the vacuolar OsTPKa K + transporter, particularly under salt stress reconfirms its important role in providing salt tolerance. The QTL locus from Horkuch containing these two transporters maybe bred into commercial rice to produce high-yielding salt tolerant rice., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Haque, Elias, Jahan and Seraj.)

Approximately, 20% of arable land worldwide, as well as nearly half of irrigated land, is subjected to salt stress. Osmotic stress and ion toxicity due to saline soils cause low crop yields. In this study, we introduced 18 families of salt-tolerant birch (Betula pendulaRoth.,Betula kirghisorumSav.-Ryczg., andBetula pubescensEhrh) into five high-salinity locations in northeastern China and evaluated their survival abilities. We also analyzed variation and stability of genotype–environment interactions of the different families under an additive main effect and multiplicative interaction model. Survival rate analysis indicated that the introduced families were well adapted to the high-salinity environments, whereas native families died. Variation analysis revealed significant differences between location × family interaction mean values for height and basic stem diameter (BSD), suggesting that most genotypes responded differently to different sites. The heritability of tree height and BSD at different sites varied from 0.416 to 0.940, with the coefficient of phenotypic variation ranging from 9.88% to 35.53%. Stability analysis indicated that some families had high tree heights but were sensitive to environmental conditions, whereas others were resistant but had average tree heights. These results suggest that families should be bred in various habitats to assess growth under favorable and unfavorable environments. [ABSTRACT FROM AUTHOR]

A novel endoglucanase gene, mgcel44, was isolated from a mangrove soil metagenomic library by functional-based screening. It encodes a 648-aa peptide with a catalytic domain of glycosyl hydrolase family 44. The deduced amino acid sequence of mgcel44 shares less than 50 % identity with endoglucanases in GenBank database. mgcel44 was cloned and overexpressed in Escherichia coli. The recombinant enzyme, MgCel44, has a molecular mass of 70.8 kDa as determined by SDS-PAGE. Its optimal pH and temperature for activity were 6 and 45 °C, respectively. It was highly active at 25-45 °C and pH 5-8. Its activity was enhanced in 0.5 M NaCl by >1.6-fold and stable up to 1.5 M NaCl. MgCel44 was resistant to several organic solvents and had high activity at 15 % (v/v) solvent after incubating for 24 h at 25 °C. [ABSTRACT FROM AUTHOR]