Low-temperature Adaptation Research Articles

Low-Temperature Adaptation Targets Genome Packing Reactions in an Icosahedral Single-Stranded DNA Virus

øX174, G4, and α3 represent the three sister genera of a Microviridae subfamily. α3-like genomes are considerably larger than their sister genera genomes, yet they are packaged into capsids of similar internal volumes. They also contain multiple A* genes, which are nested within the larger A gene reading frame. Although unessential under most conditions, A* proteins mediate the fidelity of packaging reactions. Larger genomes and multiple A* genes may indicate that genome packaging is more problematic for α3-like viruses, especially at lower temperatures, where DNA persistence lengths would be longer. Unlike members of the other genera, which reliably form plaques at 20°C, α3-like phages are naturally cold sensitive below 28°C. To determine whether there was a connection between the uniquely α3-like genome characteristics and the cold-sensitive phenotype, the α3 assembly pathway was characterized at low temperature. Although virions were not detected, particles consistent with off-pathway packaging complexes were observed. In a complementary evolutionary approach, α3 was experimentally evolved to grow at progressively lower temperatures. The two major responses to cold adaptation were genome reduction and elevated A* gene expression. IMPORTANCE The production of enzymes, transcription factors, and viral receptors directly influences the niches viruses can inhabit. Some prokaryotic hosts can thrive in widely differing environments; thus, physical parameters, such as temperature, should also be considered. These variables may directly alter host physiology, preventing viral replication. Alternatively, they could negatively inhibit infection processes in a host-independent manner. The members of three sister Microviridae genera (canonical species øX174, G4 and α3) infect the same host, but α3-like viruses are naturally cold sensitive, which could effectively exclude them from low-temperature environments (<28°C). Exclusion appeared to be independent of host cell physiology. Instead, it could be largely attributed to low-temperature packaging defects. The results presented here demonstrate how physical parameters, such as temperature, can directly influence viral diversification and niche determination in a host-independent manner.

Viability of Embryo Sacs and Fruit Set in Different Plum (Prunus domestica L.) Cultivars Grown under Norwegian Climatic Conditions.

Compatibility and synchrony between specialized tissues of the pistil, female gametophytes and male gametophytes, are necessary for successful pollination, fertilization, and fruit set in angiosperms. The aim of the present work was to study the development and viability of embryo sacs, as well as fertilization success, in relation to the fruit set of the cultivars ‘Mallard’, ‘Edda’, ‘Jubileum’, and ‘Reeves’, under specific Norwegian climatic conditions. Emasculated, unpollinated, and open-pollinated flowers were collected at the beginning of flowering, and on the 3rd, 6th, 9th, and 12th days after flowering, from all four plum cultivars over two years (2018/2019). Ovaries were dehydrated, embedded in paraffin wax, sectioned, stained, and observed under a light microscope. Results showed the existence of synchronization between successive phases in the development of the embryo sac and individual phases of flowering. All plum cultivars had higher percentages of viable embryo sacs, fertilized embryo sacs, and fruit set in 2018 than in 2019. These differences may be related to the very low temperatures during the post-full-flowering period in 2019, and to the low adaptation of some studied cultivars to unfavorable conditions. In our study, the cultivar ‘Jubileum’ showed the highest percentage of viable embryo sacs, fertilized embryo sacs, and fruit set compared to other cultivars, i.e., the best low-temperature adaptation.

Evaluation of Low-Temperature Adaptability of Different of Lily Varieties

Evaluation of Low-Temperature Adaptability of Different of Lily Varieties

Advanced Aqueous Zinc Battery with Excellent Rate and Low-Temperature Adaptation Enabled by Bimetallic Phosphide with Hetero-Interface

Advanced Aqueous Zinc Battery with Excellent Rate and Low-Temperature Adaptation Enabled by Bimetallic Phosphide with Hetero-Interface

Research and application progress of transcritical CO2 refrigeration cycle system: a review

AbstractCO2 refrigerant and its transcritical cycle system have become the research focus in the refrigeration field due to their advantages of environmentally friendly, safe and low environmental temperature adaptability. This paper summarizes the research progress on the modified methods for the defects of basic transcritical CO2 refrigeration cycle system in recent years. Meanwhile, the technical status of transcritical CO2 refrigeration technology in commercial supermarket refrigeration, heat pump system, automobile air conditioning and artificial ice rink is discussed in detail. Finally, the development of transcritical CO2 refrigeration cycle system is prospected and the key problems to be solved are put forward.

Adaptation of anammox bacteria to low temperature via gradual acclimation and cold shocks: Distinctions in protein expression, membrane composition and activities

Anammox bacteria enable efficient removal of nitrogen from sewage in processes involving partial nitritation and anammox (PN/A) or nitrification, partial denitrification, and anammox (N-PdN/A). In mild climates, anammox bacteria must be adapted to ≤15 °C, typically by gradual temperature decrease; however, this takes months or years. To reduce the time necessary for the adaptation, an unconventional method of ‘cold shocks’ is promising, involving hours-long exposure of anammox biomass to extremely low temperatures. We compared the efficacies of gradual temperature decrease and cold shocks to increase the metabolic activity of anammox (fed batch reactor, planktonic “Ca. Kuenenia”). We assessed the cold shock mechanism on the level of protein expression (quantitative shot-gun proteomics, LCHRMS/MS) and the structure of membrane lipids (UPLCHRMS/MS). The shocked culture was more active (0.66±0.06 vs 0.48±0.06 kg-N/kg-VSS/d) and maintained the relative content of N-respiration proteins at levels consistent levels with the initial state, whereas the content of these proteins decreased in gradually acclimated culture. Cold shocks also induced a more efficient expression of potential cold shock proteins (e.g. ppiD, UspA, pqqC), while putative cold shock proteins CspB and TypA were upregulated in both cultures. Ladderane lipids characteristic for anammox evolved to a similar end-point in both cultures; this confirms their role in anammox bacteria adaptation to cold and indicates a three-pronged adaptation mechanism (ladderane alkyl length, introduction of shorter non-ladderane alkyls, polar headgroup). Overall, we show the outstanding potential of cold shocks for low-temperature adaptation of anammox bacteria and provide yet unreported detailed mechanisms of anammox adaptation to low temperatures.

Effects of different colorants on service performance for colored asphalt pavement in cold regions

PurposeThe service performance for colored asphalt pavement is inevitably affected by the addition of different colorants, especially the challenge of low temperature environment in cold regions. Therefore, the purpose of study is to explore the effects of different colorants on the service performance for colored asphalt pavement and to provide a foundation for improving the applicability of colored asphalt pavement in cold regions.Design/methodology/approachIn the study, three kinds of colorants (iron oxide red, iron oxide yellow, iron oxide green) were used to compare the influence of different colorants amounts and different colorants kinds on the service performance for colored asphalt pavement in cold regions. According to the characteristics of low temperature in cold regions, the effects of different colorants on the low temperature performance for colored asphalt pavement were studied.FindingsThe study shows that different colorants have different effects on the service performance of colored asphalt pavement. The high temperature performance increases with the increase of the colorants amount, but the low temperature performance is opposite. Additionally, the yellow colored asphalt pavement has more advantages of low temperature adaptation than the red and green colored asphalt pavement.Originality/valueThe study results provide a certain theoretical foundation for the application of colored asphalt pavement in cold regions and have certain value and significance for the further development of colored asphalt pavement.

Engineering Self-Adhesive Polyzwitterionic Hydrogel Electrolytes for Flexible Zinc-Ion Hybrid Capacitors with Superior Low-Temperature Adaptability.

Flexible zinc-ion hybrid capacitors (ZIHCs) based on hydrogel electrolytes are an up-and-coming and highly promising candidate for potential large-scale energy storage due to their combined complementary advantages of zinc batteries and capacitors. However, the freezing induces a sharp drop in conductivity and mechanical property with tremendous compromise of the interfacial adhesion, thereby severely impeding the low-temperature application of such flexible ZIHCs. To achieve the flexible ZIHCs with excellent low-temperature adaptability, an antifreezing and self-adhesive polyzwitterionic hydrogel electrolyte (PZHE) is engineered via a self-catalytic nano-reinforced strategy, affording unparalleled conductivity and robust interfacial adhesion, together with superhigh mechanical strength over a broad temperature ranging from 25 to -60 °C. Meanwhile, the water-in-salt-type PZHE filled with ZnCl2 can provide ion migration channels to enhance the reversibility of Zn metal electrodes, thus greatly reducing side reactions and extending the cycling life. With distinctive integrated merits of the water-in-salt type PZHE, the as-built ZIHCs deliver a high-level energy density of 80.5 Wh kg-1, a desired specific capacity of 81.5 mAh g-1, along with a long-duration cycling lifespan (100 000 cycles) with 84.6% capacity retention at -40 °C, even outperforming the state-of-the-art ZIHCs at room temperature. More encouragingly, the extraordinary temperature-adaptability for both electrochemical and mechanical performance under severe mechanical challenges is achieved for the flexible ZIHCs at extremely low temperature. Noticeably, the ZIHC is also capable of operating in an ice-water bath and vacuum. It is believed that this strategy makes contributions to inspire the design and application of high-performance PZHEs in fields of flexible and wearable electronics that can work in extremely cold environments.

Chromosome-level genome assemblies of Channa argusandChanna maculata and comparative analysis of their temperature adaptability.

Background Channa argus and Channa maculata are the main cultured species of the snakehead fish family, Channidae. The relationship between them is close enough that they can mate; however, their temperature adaptability is quite different.ResultsIn this study, we sequenced and assembled the whole genomes of C. argus and C. maculata and obtained chromosome-level genome assemblies of 630.39 and 618.82 Mb, respectively. Contig N50 was 13.20 and 21.73 Mb, and scaffold N50 was 27.66 and 28.37 Mb, with 28,054 and 24,115 coding genes annotated for C. argus and C. maculata, respectively. Our analyses showed that C. argus and C. maculata have 24 and 21 chromosomes, respectively. Three pairs of chromosomes in C. argus correspond to 3 chromosomes in C. maculata, suggesting that 3 chromosomal fusion events occurred in C. maculata. Comparative analysis of their gene families showed that some immune-related genes were unique or expandable to C. maculata, such as genes related to herpes simplex infection. Analysis of the transcriptome differences related to temperature adaptation revealed that the brain and liver of C. argus rapidly produced more differentially expressed genes than C. maculata. Genes in the FoxO signalling pathway were significantly enriched in C. argus during the cooling process (P < 0.05), and the expression of 3 transcription factor genes in this pathway was significantly different between C. argus and C. maculata (P < 0.01).Conclusions C. maculata may have higher resistance to certain diseases, whereas C. argus has a faster and stronger response to low-temperature stress and thus has better adaptability to a low-temperature environment. This study provides a high-quality genome research platform for follow-up studies of Channidae and provides important clues regarding differences in the low-temperature adaptations of fish.

Functional implication of heat shock protein 70/90 and tubulin in cold stress of Dermacentor silvarum

BackgroundThe tick Dermacentor silvarum Olenev (Acari: Ixodidae) is a vital vector tick species mainly distributed in the north of China and overwinters in the unfed adult stage. The knowledge of the mechanism that underlies its molecular adaptation against cold is limited. In the present study, genes of hsp70 and hsp90 cDNA, named Dshsp70 and Dshsp90, and tubulin were cloned and characterized from D. silvarum, and their functions in cold stress were further evaluated.MethodsThe genome of the heat shock proteins and tubulin of D. silvarum were sequenced and analyzed using bioinformatics methods. Each group of 20 ticks were injected in triplicate with Dshsp90-, Dshsp70-, and tubulin-derived dsRNA, whereas the control group was injected with GFP dsRNA. Then, the total RNA was extracted and cDNA was synthesized and subjected to RT-qPCR. After the confirmation of knockdown, the ticks were incubated for 24 h and were exposed to − 20 °C lethal temperature (LT50), and then the mortality was calculated.ResultsResults indicated that Dshsp70 and Dshsp90 contained an open reading frame of 345 and 2190 nucleotides that encoded 114 and 729 amino acid residues, respectively. The transcript Dshsp70 showed 90% similarity with that identified from Dermacentor variabilis, whereas Dshsp90 showed 85% similarity with that identified from Ixodes scapularis. Multiple sequence alignment indicates that the deduced amino acid sequences of D. silvarum Hsp90, Hsp70, and tubulin show very high sequence identity to their corresponding sequences in other species. Hsp90 and Hsp70 display highly conserved and signature amino acid sequences with well-conserved MEEVD motif at the C-terminal in Hsp90 and a variable C-terminal region with a V/IEEVD-motif in Hsp70 that bind to numerous co-chaperones. RNA interference revealed that the mortality of D. silvarum was significantly increased after injection of dsRNA of Dshsp70 (P = 0.0298) and tubulin (P = 0.0448), whereas no significant increases were observed after the interference of Dshsp90 (P = 0.0709).ConclusionsThe above results suggested that Dshsp70 and tubulin play an essential role in the low-temperature adaptation of ticks. The results of this study can contribute to the understanding of the survival and acclimatization of overwintering ticks.Graphical abstract

Cold hardiness in grapevines of various ecological and geographical origin

Over past years, grapevine adaptability has become of primary concern due to sharp cold-stressing weather of the unstable climates of Southern Russia accompanied by increasing mean annual temperatures, including higher degrees during plant winter dormancy. This situation causes considerable injury to the generative and vegetative organs in bush vine. Physiological and biochemical studies of the vine plant are of great importance for breeding cold-hardy grape genotypes. The article presents research related to studying cold hardiness in different grape varieties by content dynamics of starch, soluble sugars, abscisic acid and potassium ions in plant bark and buds. We studied grape varieties (interspecies hybrids) of the European-American (Dostoinyi, Krasnostop, Vostorg), West-European (Aligote), East-European (Zarif) and European-Amur-American origins (Kristall). The work aimed to analyse the physiological and biochemical properties of various ecological and geographical-origin grapes in winter time in order to identify the cold-hardiest genotypes. The Krasnostop and Vostorg varieties were ascertained as cold-hardy. Physiological and biochemical assays revealed an important contribution of water-soluble sugar-producing starch hydrolysis to low-temperature adaptation in Krasnostop and Vostorg, with the sugar content increasing 2.7-2.9 times. Krasnostop and Zarif were found to elevate the sucrose osmoprotectant winter level 4.7 and 6.6 times, respectively. All grape varieties decreased the abscisic acid content due to protective functions. Aligote was identified susceptible basing on a 2.3-fold potassium ion increase in frozen bark cell extract. The research conducted establishes the diagnostic value of the abovementioned physiological and biochemical parameters for cold hardiness evaluation in grape varieties.

Low-temperature adaptive conductive hydrogel based on ice structuring proteins/CaCl2 anti-freeze system as wearable strain and temperature sensor

Conductive hydrogels as wearable devices meet the basic demands of mechanical flexibility and smart sensing. However, achieving anti-freeze property in conductive hydrogels is still challengeable. Here, a novel anti-freezing system based on ice structuring proteins and CaCl2 was introduced to enable a conductive hydrogel with low-temperature adaptability. Both formation of ice nuclei and ice growth of the hydrogel at sub-zero temperature could be inhibited. Supported by the anti-freeze system, the hydrogel revealed good flexibility (890% at −20 °C), recovery and conductivity (0.50 S/m at −20 °C) at both room temperature and sub-zero temperature. The low-temperature adaptability enabled the hydrogel to be used as strain and temperature sensors at both room temperature and sub-zero temperature. The anti-freeze system in this work is expected to open up a new avenue to promote the conductive hydrogel with low-temperature adaptability.

Natural variation in a type-A response regulator confers maize chilling tolerance

Maize (Zea mays L.) is a cold-sensitive species that often faces chilling stress, which adversely affects growth and reproduction. However, the genetic basis of low-temperature adaptation in maize remains unclear. Here, we demonstrate that natural variation in the type-A Response Regulator 1 (ZmRR1) gene leads to differences in chilling tolerance among maize inbred lines. Association analysis reveals that InDel-35 of ZmRR1, encoding a protein harboring a mitogen-activated protein kinase (MPK) phosphorylation residue, is strongly associated with chilling tolerance. ZmMPK8, a negative regulator of chilling tolerance, interacts with and phosphorylates ZmRR1 at Ser15. The deletion of a 45-bp region of ZmRR1 harboring Ser15 inhibits its degradation via the 26 S proteasome pathway by preventing its phosphorylation by ZmMPK8. Transcriptome analysis indicates that ZmRR1 positively regulates the expression of ZmDREB1 and Cellulose synthase (CesA) genes to enhance chilling tolerance. Our findings thus provide a potential genetic resource for improving chilling tolerance in maize.

Evaluation of energy storage performance of ferroelectric materials by equivalent circuit model

Dielectric capacitors with large energy storage density, low hysteresis loss, low temperature dependence and high temperature adaptability show great advantages in high temperature applications of electronic devices. In this work, a large energy storage density (W ~ 28.776 J/cm3) and ultra-high efficiency (η ~ 87.36%) have been simultaneously achieved in the CuX(Ba0.88Ca0.12)1-X(Zr0.12Ti0.88)O3 (X = 0.1) lead-free relaxor ferroelectric thin film capacitors deposited on Pt(111)/TiOX/SiO2/Si(100) substrates by using a sol-gel method. The results show that the dielectric permittivity and dielectric loss change a little in the temperature range of 30–400 °C. The reason of low dielectric loss and temperature insensitivity is revealed by means of Raman spectrum fitting and equivalent circuit model (the I-E curve of ferroelectric materials is regarded as an equivalent circuit of equivalent capacitance (C), equivalent resistance (R) and polarization charge (Ip(t)) in parallel, given by the equation I(t)=V(t)/R+KC+Ip(t)). The results prove that the stability of slope (K) is positively correlated with the stability of energy storage performance of ferroelectric materials, which provides the basis for the evaluation of energy storage performance of ferroelectric materials.

Inoculating with the microbial agents to start up the aerobic composting of mushroom residue and wood chips at low temperature

Aerobic composting of cellulosic biomass is difficult to start at low temperatures. Especially, the effect of microbial inoculants on the initiation of aerobic composting of cellulosic material at low temperature and the succession of microbial community is still poorly defined. In this study, the aerobic composting of mushroom residue and wood chips successfully started at 3–11 °C by inoculating the microbial agents (including bacteria and fungi) for cellulose degradation and low temperature adaptation. It was found that the inoculum was beneficial for the heating of the compost pile, starting of the aerobic composting process and the degradation of cellulose. The thermophilic stage of inoculation group lasted for 13 days and 8 days longer than that of control group. The degradation efficiencies of hemicellulose and cellulose in inoculation group and control group were 37.50% and 27.30%, while the degradation efficiencies of cellulose were 21.29% and 16.18%, respectively. Furthermore, the results of high-throughput sequencing revealed that inoculation of microbial agents was beneficial to the optimization of community structure and the conversion of cellulose substrate. In addition, the inoculated strains of Aspergillus, Penicillium, Bacillus and Streptomyces might play active roles in the composting process, especially in the set-up and thermophilic stage of the composting.

Natural population re-sequencing detects the genetic basis of local adaptation to low temperature in a woody plant.

Total of 14 SNPs associated with overwintering-related traits and 75 selective regions were detected. Important candidate genes were identified and a possible network of cold-stress responses in woody plants was proposed. Local adaptation to low temperature is essential for woody plants to against changeable climate and safely survive the winter. To uncover the specific molecular mechanism of low temperature adaptation in woody plants, we sequenced 134 core individuals selected from 494 paper mulberry (Broussonetia papyrifera), which naturally distributed in different climate zones and latitudes. The population structure analysis, PCA analysis and neighbor-joining tree analysis indicated that the individuals were classified into three clusters, which showed forceful geographic distribution patterns because of the adaptation to local climate. Using two overwintering phenotypic data collected at high latitudes of 40°N and one bioclimatic variable, genome-phenotype and genome-environment associations, and genome-wide scans were performed. We detected 75 selective regions which possibly undergone temperature selection and identified 14 trait-associated SNPs that corresponded to 16 candidate genes (including LRR-RLK, PP2A, BCS1, etc.). Meanwhile, low temperature adaptation was also supported by other three trait-associated SNPs which exhibiting significant differences in overwintering traits between alleles within three geographic groups. To sum up, a possible network of cold signal perception and responses in woody plants were proposed, including important genes that have been confirmed in previous studies while others could be key potential candidates of woody plants. Overall, our results highlighted the specific and complex molecular mechanism of low temperature adaptation and overwintering of woody plants.

Low-Temperature Adaptation of the Rana temporaria Gastrocnemius Muscle at the Onset of Anabiosis

Low-Temperature Adaptation of the Rana temporaria Gastrocnemius Muscle at the Onset of Anabiosis

Increasing loop flexibility affords low-temperature adaptation of a moderate thermophilic malate dehydrogenase from Geobacillus stearothermophilus.

Malate dehydrogenase (MDH) catalyzes the reversible reduction of nicotinamide adenine dinucleotide from oxaloacetate to L-malate. MDH from moderate thermophilic Geobacillus stearothermophilus (gs-MDH) has high thermal stability and substrate specificity and is used as a diagnostic reagent. In this study, gs-MDH was engineered to increase its catalytic activity at low temperatures. Based on sequential and structural comparison with lactate dehydrogenase from G. stearothermophilus, we selected G218 as a mutation site to increase the loop flexibility pivotal for MDH catalysis. The G218 mutants showed significantly higher specific activities than the wild type at low temperatures and maintained thermal stability. The crystal structure of the G218Y mutant, which had the highest catalytic efficiency among all the G218 mutants, suggested that the flexibility of the mobile loop was successfully increased by the bulky side chain. Therefore, this study demonstrated the low-temperature adaptation of MDH by facilitating conformational changes during catalysis.

Comparative transcriptome analysis of leaves during early stages of chilling stress in two different chilling-tolerant brown-fiber cotton cultivars.

Chilling stress generates significant inhibition of normal growth and development of cotton plants and lead to severe reduction of fiber quality and yield. Currently, little is known for the molecular mechanism of brown-fiber cotton (BFC) to respond to chilling stress. Herein, RNA-sequencing (RNA-seq)-based comparative analysis of leaves under 4°C treatment in two different-tolerant BFC cultivars, chilling-sensitive (CS) XC20 and chilling-tolerant (CT) Z1612, was performed to investigate the response mechanism. A total of 72650 unigenes were identified with eight commonly used databases. Venn diagram analysis identified 1194 differentially expressed genes (DEGs) with significant up-regulation in all comparison groups. Furthermore, enrichment analyses of COG and KEGG, as well as qRT-PCR validation, indicated that 279 genes were discovered as up-regulated DEGs (UDEGs) with constant significant increased expression in CT cultivar Z1612 groups at the dimensions of both each comparison group and treatment time, locating in the enriched pathways of signal transduction, protein and carbohydrate metabolism, and cell component. Moreover, the comprehensive analyses of gene expression, physiological index and intracellular metabolite detections, and ascorbate antioxidative metabolism measurement validated the functional contributions of these identified candidate genes and pathways to chilling stress. Together, this study for the first time report the candidate key genes and metabolic pathways responding to chilling stress in BFC, and provide the effective reference for understanding the regulatory mechanism of low temperature adaptation in cotton.

Thermal destabilization mechanism of cytochrome c' from psychrophilic Shewanella violacea.

Cytochrome c' is a nitric oxide (NO)-binding heme protein found in Gram negative bacteria. The thermal stability of psychrophilic Shewanella violacea cytochrome c' (SVCP) is lower than those of its homologues from other 2 psychrophilic Shewanella species, indicating that thermal destabilization mechanism for low-temperature adaptation accumulates in SVCP. In order to understand this mechanism at the amino acid level, here the stability and function of SVCP variants, modeled using the 2 homologues, were examined. The variants exhibited increased stability, and they bound NO similar to the wild type. The vulnerability as to the SVCP stability could be attributed to less hydrogen bond at the subunit interface, more flexible loop structure, and less salt bridge on the protein surface, which appear to be its destabilization mechanism. This study provides an example for controlling stability without spoiling function in psychrophilic proteins.