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Lacticaseibacillus casei KACC92338 was originally isolated from Korean raw milk. The antioxidant activities and protective effect in vitro of this strain were evaluated extensively. The results showed that KACC92338 can tolerate hydrogen peroxide up to 2 mM and cell-free supernatant (CFS) had higher scavenging rates for DPPH, hydroxyl radical, reducing power, and iron chelating activities with 95.61 ± 1.59%, 34.10 ± 1.93%, 2.220 ± 0.82 and 81.06 ± 1.06%, respectively. Meanwhile, the CFS showed a protective effect on yeast cells against 10 mM hydrogen peroxide with a survival rate of 76.05 ± 5.65%. To explore the probiotic potential of KACC92338, whole genome assembly and gene clusters with probiotic properties were further analyzed. The genome size was 3,050,901 bp with a 47.96% GC ratio, and 63 contigs. The genome contains 3,048 genes composed of 2,981 coding sequences and 67 RNAs (including 57 tRNAs +9 rRNAs +1 tmRNA). Average Nucleotide Identity and genome-based taxonomy showed that the KACC92338 genome had close similarity with L. casei strains with 96% ANI. Functional annotation by EggNOG and KEGG revealed the presence of numerous genes putatively involved in carbohydrate- and amino acid-transport and metabolism, genetic information processing, and signaling and cellular processes. Additionally, several genes conferring probiotic characteristics such as tolerance to stress, heat, cold, acid, bile salts, oxidative stress, immunomodulation, and adhesion to intestinal epithelium were identified. Notably absent were acquired antibiotic resistance genes, virulence, and pathogenic factors, that prove KACC92338 is a safe strain. Besides, the defense mechanisms of KACC92338 include six prophage regions and three clustered regularly interspaced short palindromic repeat (CRISPR) arrays as acquired immune systems against mobile elements. Further, the BAGEL4 database determined antimicrobial bacteriocin clusters of class IIb: sakacin-P, Enterolysin_A, sactipeptides, and Enterocin X, which suggests the strain could exhibit a wide range of antimicrobial functions. Together, these findings show that the L. casei KACC92338 strain can be a potential probiotic candidate in producing functional fermented foods-, health care- and skin care products-with antioxidant properties. However, a few more mechanistic studies are necessary on the safety assurance and potential application of the strain as a probiotic agent. [ABSTRACT FROM AUTHOR]

Lacticaseibacillus casei KACC92338 was originally isolated from Korean raw milk. The antioxidant activities and protective effect in vitro of this strain were evaluated extensively. The results showed that KACC92338 can tolerate hydrogen peroxide up to 2 mM and cell-free supernatant (CFS) had higher scavenging rates for DPPH, hydroxyl radical, reducing power, and iron chelating activities with 95.61 ± 1.59%, 34.10 ± 1.93%, 2.220 ± 0.82 and 81.06 ± 1.06%, respectively. Meanwhile, the CFS showed a protective effect on yeast cells against 10 mM hydrogen peroxide with a survival rate of 76.05 ± 5.65%. To explore the probiotic potential of KACC92338, whole genome assembly and gene clusters with probiotic properties were further analyzed. The genome size was 3,050,901 bp with a 47.96% GC ratio, and 63 contigs. The genome contains 3,048 genes composed of 2,981 coding sequences and 67 RNAs (including 57 tRNAs +9 rRNAs +1 tmRNA). Average Nucleotide Identity and genome-based taxonomy showed that the KACC92338 genome had close similarity with L. casei strains with 96% ANI. Functional annotation by EggNOG and KEGG revealed the presence of numerous genes putatively involved in carbohydrate- and amino acid-transport and metabolism, genetic information processing, and signaling and cellular processes. Additionally, several genes conferring probiotic characteristics such as tolerance to stress, heat, cold, acid, bile salts, oxidative stress, immunomodulation, and adhesion to intestinal epithelium were identified. Notably absent were acquired antibiotic resistance genes, virulence, and pathogenic factors, that prove KACC92338 is a safe strain. Besides, the defense mechanisms of KACC92338 include six prophage regions and three clustered regularly interspaced short palindromic repeat (CRISPR) arrays as acquired immune systems against mobile elements. Further, the BAGEL4 database determined antimicrobial bacteriocin clusters of class IIb: sakacin-P, Enterolysin_A, sactipeptides, and Enterocin X, which suggests the strain could exhibit a wide range of antimicrobial functions. Together, these findings show that the L. casei KACC92338 strain can be a potential probiotic candidate in producing functional fermented foods-, health care- and skin care products-with antioxidant properties. However, a few more mechanistic studies are necessary on the safety assurance and potential application of the strain as a probiotic agent. [ABSTRACT FROM AUTHOR]

Fusarium head blight (FHB) represents a damaging disease of cereal spikes caused by mycotoxin-producing Fusarium fungi revealing adverse effects on grain quality and yield. Chinese spring wheat (Triticum aestivum L.) cv. Sumai 3 represents a major source of FHB resistance thanks to Fhb1 QTL on 3BS chromosome conferring resistance to FHB and encoding a lectin-like protein. The aim of our study lied in a comparison of proteome response to Fusarium culmorum inoculation and mycotoxin deoxynivalenol (DON) application at 10 d after inoculation (dai) in spikes of resistant wheat cultivar Sumai 3 and susceptible wheat cultivar SW Kadrilj. Proteome analysis revealed profound impact of Fusarium inoculation and mycotoxin application on plant energy metabolism. Fusarium inoculation decreased photosynthesis and ATP biosynthesis and increased the level of stress-protective proteins (chaperones such as Hsc70, lectins). Genotype related differences observed at 10 dai indicated an active acclimation in Sumai 3 as indicated by increased content of some enzymes involved in phenolics biosynthesis (phenylalanine ammonia lyase PAL, BAHD acyltransferase), jasmonate biosynthesis (lipoxygenase LOX), and oligosaccharide biosynthesis (sucrose synthase SuSy, UDP-glucose uridylyltransferase) which are an important part of glycoproteins such as lectins and other pathogen-responsive biomolecules. The study thus provides data on plant acclimation to Fusarium infection which may underlie superior resistance of Sumai 3 cultivar. [ABSTRACT FROM AUTHOR]

Main conclusion : In maize, leaf proteome responses evoked by soil drought applied separately differ from those evoked by mite feeding or both types of stresses occurring simultaneously. This study focuses on the involvement of proteomic changes in defence responses of a conventional maize cultivar (Bosman) to the two-spotted spider mite infestation, soil drought and both stresses coexisting for 6 days. Under watering cessation or mite feeding applied separately, the protein carbonylation was not directly linked to the antioxidant enzymes' activities. Protein carbonylation increased at higher and lower SOD, APX, GR, POX, PPO activities following soil drought and mite feeding, respectively. Combination of these stresses resulted in protein carbonylation decrease despite the increased activity of all antioxidant enzymes (except the CAT). However, maize protein network modification remains unknown upon biotic/abiotic stresses overlapping. Here, using multivariate chemometric methods, 94 leaf protein spots (out of 358 considered; 2-DE) were identified (LC-MS/MS) as differentiating the studied treatments. Only 43 of them had individual discrimination power. The soil drought increased abundance of leaf proteins related mainly to photosynthesis, carbohydrate metabolism, defence (molecular chaperons) and protection. On the contrary, mite feeding decreased the abundance of photosynthesis related proteins and enhanced the abundance of proteins protecting the mite-infested leaf against photoinhibition. The drought and mites occurring simultaneously increased abundance of proteins that may improve the efficiency of carbon fixation, as well as carbohydrate and amino acid metabolism. Furthermore, increased abundance of the Rubisco large subunit-binding protein (subunit β), fructose-bisphosphate aldolase and mitochondrial precursor of Mn-SOD and decreased abundance of the glycolysis-related enzymes in the mite-free leaf (in the vicinity of mite-infested leaf) illustrate the involvement of these proteins in systemic maize response to mite feeding. [ABSTRACT FROM AUTHOR]

Araucaria angustifolia is a critically endangered conifer native to South America, and somatic embryogenesis (SE) is one of the most promising biotechnological tools for its conservation and mass propagation. In vitro tissue culture and chemical compounds supplemented to culture medium, especially plant growth regulators (PGRs), are known to affect DNA methylation and protein expression profiles, modulating the phenotype and/or the embryogenic potential. Here, we evaluated the global DNA methylation (GDM) levels of A. angustifolia embryogenic cultures (EC) during SE induction and multiplication steps for 1 year subcultures, and identified a wide range of differentially expressed proteins in PGR-free or -supplemented treatments. During long-term subcultures, PGR-supplementation proved to gradually increase the GDM, which may compromise genomic stability and evoke gene expression modifications. Label-free proteomics enabled a robust protein identification and quantification in A. angustifolia EC. Exclusively expression of PIN-like protein in PGR-supplemented treatment indicated a possible differential response of the EC to polar auxin transport, which can generate implications in its morphogenetic response to maturation step. Up-regulation of stress-related proteins in EC from PGR-supplemented treatment suggests its more stressful environment, triggering notable responses to hormonal, osmotic and oxidative stresses. Improved expression of proteins involved with protein folding and stabilization processes in PGR-free treatment could play a protective function in response to stress conditions caused by in vitro culture, and may provide an adaptive advantage to these EC. The expression of several proteins associated to terpenoid biosynthesis suggests that EC from both treatments and cell lines are possibly producing these compounds. [ABSTRACT FROM AUTHOR]

The periplasmic proteome of recombinant E. coli cells expressing human interferon-α2b (INF-α2b) was analysed by 2D-gel electrophoresis to find the most altered proteins. Of some unique up- and down-regulated proteins in the proteome, ten were identified by MS. The majority of the proteins belonged to the ABC transporter protein family. Other affected proteins were ones involved in the regulation of transcription such as DNA-binding response regulator, stress-related proteins and ecotin. Thus, the production of INF-α2b acts as a stress on the cells and results in the induction of various transporters and stress related proteins. [ABSTRACT FROM AUTHOR]

Aims: To complement our proteome study, whole-transcriptome analyses were utilized here to identify proteins related to degrading cis-1,2-dichloroethylene ( cis-DCE). Methods and Results: Metabolically engineered Escherichia coli strains were utilized expressing an evolved toluene ortho-monooxygenase along with either (i) glutathione S-transferase and altered γ-glutamylcysteine synthetase or (ii) a rationally engineered epoxide hydrolase. cis-DCE degradation induced 30 known stress genes and 32 uncharacterized genes. Because of the reactive cis-DCE epoxides formed, we hypothesized that some of these uncharacterized genes may be related to a variety of stresses. Using isogenic mutants, IbpB, YchH, YdeI, YeaR, YgiW, YoaG and YodD were related to hydrogen peroxide, cadmium and acid stress. Additional whole-transcriptome studies with hydrogen peroxide stress using the most hydrogen peroxide-sensitive mutants, ygiW and ychH, identified that FliS, GalS, HcaR, MglA, SufE, SufS, Tap, TnaB, YhcN and YjaA are also involved in the stress response of E. coli to hydrogen peroxide, cadmium and acid, as well as are involved in biofilm formation. Conclusion: Seventeen proteins are involved in the stress network for this organism, and YhcN and YchH were shown to be important for the degradation of cis-DCE. Significance and Impact of the Study: Six previously uncharacterized proteins (YchH, YdeI, YgiW, YhcN, YjaA and YodD) were shown to be stress proteins. [ABSTRACT FROM AUTHOR]

The effect of cadmium-induced oxidative stress, with or without glutathione supplementation, was investigated in the single cell eukaryotic phytoflagellate, Euglena gracilis strains Z and its achlorophyllous mutant SMZ as experimental models. Both these strains actively synthesize thiols to prevent or resist cadmium toxicity. The content of glutathione, as a representative antioxidant, was also examined in both strains. Exposure to cadmium induced heat-shock protein 70 (HSP70) synthesis in both strains of E. gracilis. Glutathione supplementation also induced HSP70. Overall, these results indicate that glutathione was closely linked to the induction of stress-related proteins. The sensitivity to cadmium-stress was higher in strain Z than SMZ. The results suggest that chloroplasts may have a role in the regulation of HSP70 expression. The relationship between HSP70 and GSH levels is still far from understood, and further research may shed light upon their up-regulation in the presence of Cd. [ABSTRACT FROM AUTHOR]

The effects of anoxic submergence (16 h at 15°C) on cellular mRNA contents were assessed in five organs of anoxia tolerant turtles Trachemys scripta elegans. Poly(A) RNA was extracted from liver, red and white skeletal muscle, kidney and heart of control and anoxic turtles, as well as from heart and kidney of turtles allowed 24 h aerobic recovery (at 15°C) after anoxia exposure. Poly(A) RNA content increased by 30% in white muscle from anoxic turtles relative to control animals but was unchanged by metabolic state in other organs. Extracted mRNA was translated in vitro in a wheat germ lysate system and the S-labelled polypeptides that were produced were separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Overall translational activity of the mRNA pool [cpm S-methionine incorporated per microgram poly(A) RNA] was altered by anoxia exposure in three organs, increasing by 38 and 18% in liver and kidney and decreasing by 42% in red muscle. Anoxia exposure also led to qualitative changes in the protein products that resulted from in vitro translation. Sodium dodecyl sulphate polyacrylamide gel electrophoresis revealed the presence of a novel 19.5-kDa polypeptide in liver of anoxia-exposed animals as well as increased amounts of two other proteins at 28.6 and 79.9 kDa.In heart a new translation product of 26.8 kDa was produced during the aerobic recovery period after anoxia exposure. Anoxia stimulated the appearance of a 37.5-kDa protein in red skeletal muscle but anoxic red muscle also lost proteins of 40, 32, and 28.2 kDa that were present in aerobic controls. Anoxia exposure did not change the proteins produced by in vitro translation in white muscle. The results suggest that anoxia exposure triggers rapid cellular responses in T. s. elegans that modify translatable mRNA populations in organs, leading to new protein transcripts. This response may be one of the important molecular adaptations that support the natural anoxia tolerance of this species. [ABSTRACT FROM AUTHOR]

A halophilic Gram-negative eubacterium was isolated from the Iroise Sea and identified as an efficient producer of polyhydroxyalkanoates (PHA). The strain, designated SF2003, was found to belong to the Halomonas genus on the basis of 16S rRNA gene sequence similarity. Previous biochemical tests indicated that the Halomonas sp. strain SF2003 is capable of supporting various culture conditions which sometimes can be constraining for marine strains. This versatility could be of great interest for biotechnological applications. Therefore, a complete bacterial genome sequencing and de novo assembly were performed using a PacBio RSII sequencer and Hierarchical Genome Assembly Process software in order to predict Halomonas sp. SF2003 metabolisms, and to identify genes involved in PHA production and stress tolerance. This study demonstrates the complete genome sequence of Halomonas sp. SF2003 which contains a circular 4,36 Mbp chromosome, and replaces the strain in a phylogenetic tree. Genes related to PHA metabolism, carbohydrate metabolism, fatty acid metabolism and stress tolerance were identified and a comparison was made with metabolisms of relative species. Genes annotation highlighted the presence of typical genes involved in PHA biosynthesis such as phaA, phaB and phaC and enabled a preliminary analysis of their organization and characteristics. Several genes of carbohydrates and fatty acid metabolisms were also identified which provided helpful insights into both a better knowledge of the intricacies of PHA biosynthetic pathways and of production purposes. Results show the strong versatility of Halomonas sp. SF2003 to adapt to various temperatures and salinity which can subsequently be exploited for industrial applications such as PHA production. [ABSTRACT FROM AUTHOR]