Search Results (50)

Extracellular DNA (eDNA) has gained attention as a danger signal between organisms because of the ecological implications of this mechanism and its great potential as a biological modulator in agriculture. Self-DNA and non-self DNA have been evaluated earlier, both as plant immune system elicitors. Here we show the effect of eDNA extracted from the bacterial phytopathogen Clavibacter michiganensis applied to tomato plants in different concentrations (50, 100 and 150 µg mL⁻¹). Monitoring morphology of the plants, spectrophotometric determinations and RT-qPCR assays showed a dose-dependent effect on plant growth and root development, activation of antioxidant enzymes such as catalase and superoxide dismutase, biosynthesis of secondary metabolites, including phenolic compounds and flavonoids, and differential expression of genes related to plant stress response, such as chalcone synthase and phenylalanine ammonia-lyase. Lower concentration treatments showed an increment in the variables as beneficial responses for agricultural practices, and the higher concentration (150 µg mL⁻¹) showed reduced or no effects on the evaluated variables. This work represents a step forward in the development of effective and more sustainable agricultural technology in crop production. Full article

Glucose is the principal energy substrate for the brain. Hypo- and hyperglycemic episodes frequently occur in senescent people, contributing to functional and structural impairment of brain neurons and causing cognitive deficits in this population. In this study, we investigate whether long-term changes in the extracellular concentration of glucose affect viability and transmitter functions of septum-derived SN56 cholinergic neuronal cells through alterations in acetyl-CoA availability. Cells with low cholinergic expression (NCs) and cAMP/retinoic acid-induced high cholinergic expression (DCs) were investigated. Hypoglycemia brought about similar (approximately 20–30%) decreases in pyruvate dehydrogenase complex (PDHC) and ATP-citrate lyase (ACLY) activities and a 65% decline in lactate dehydrogenase (LDH) activity in NCs and DCs. Choline acetyltransferase (ChAT) and LDH activities in DCs were about 3–8 and 1.7–2.4 times higher than in NCs over the tested glucose concentration range, respectively. DCs appeared to be more resistant than NCs to hypoglycemia, as evidenced by lower glucose IC₅₀ values for cell count and intracellular LDH activity. On the other hand, some of functional properties of DCs, such as the cholinergic phenotype and their plasma membrane functions (trypan blue exclusion, TB+), were found to be more sensitive to hypoglycemia than those of NCs, as demonstrated by the higher IC₅₀ for glucose in DCs. Acetyl-CoA levels in DCs were 40% lower than in NCs, and decreased by about 25% with increasing hypoglycemia in both cell types. The cytotoxic effects of amyloid-β_25–35 (Aβ) and sodium nitroprusside (SNP; NO generator) were also tested. In 25 mM glucose medium, these toxic compounds exerted greater detrimental effects on DCs than on NCs. In contrast, in 1 mM glucose, more evident cytotoxicity of SNP and Aβ was observed in NCs. These data suggest that the higher rate of glycolysis in differentiated cholinergic septal neurons may be a protective mechanism against hypoglycemia. Full article

Glyphosate [N-(phosphonomethyl)glycine] is the most widely used herbicide worldwide, and its environmental persistence has prompted increasing interest in microbial processes that may contribute to its dissipation. This study evaluated a collection of 15 soil-derived actinobacterial strains for plant growth-promoting traits, extracellular enzymatic activities, glyphosate tolerance, and glyphosate removal under nutrient-sufficient and phosphate-starved conditions. Herbicide tolerance evaluated on agar plates was widespread across the collection, with all strains sustaining growth at 10 and 50 g L⁻¹ of glyphosate. Under nutrient-sufficient conditions glyphosate removal remained limited, with maximum values of 16.15 ± 2.08% (Streptomyces sp. Con7.16) and 15.34 ± 2.89% (Streptomyces sp. Z38). In contrast, prior phosphate starvation markedly enhanced removal efficiency, reaching 42.21 ± 3.59% in Streptomyces sp. Z38 and 39.46 ± 1.94% in Streptomyces sp. Con7.16. Transmission electron microscopy coupled with X-ray microanalysis in the selected Streptomyces sp. Z38 revealed starvation-associated depletion of intracellular polyphosphate granules, followed by partial replenishment when glyphosate was supplied as the sole phosphorus source, consistent with indirect evidence of glyphosate-derived phosphorus acquisition. Genome mining of Streptomyces sp. Z38 identified candidate genes potentially consistent with a non-canonical, C-P lyase-independent phosphonate utilization route; however, these assignments are based exclusively on bioinformatic evidence and require experimental validation. Collectively, these findings indicate that phosphate limitation enhances glyphosate removal in the selected actinobacteria, and the physiological and genomic data are consistent with a starvation-triggered shift toward alternative phosphorus scavenging strategies. Because this strain is intended for future phytoremediation applications in glyphosate-contaminated agricultural soils, elucidating the underlying phosphorus dynamics is essential for anticipating its functional behavior and environmental relevance. Full article

Hyaluronan (HA) is a major extracellular matrix glycosaminoglycan essential for tissue integrity, immune homeostasis, and host defense. Many microbial pathogens exploit host HA by producing hyaluronidases (Hyls), enzymes that degrade HA to promote tissue invasion, nutrient acquisition, immune modulation, and biofilm formation. Unlike mammalian Hyls, microbial Hyls predominantly function as β-elimination lyases, generating unsaturated disaccharides and oligosaccharides with distinct biological activities. Recent mechanistic and structural insights reveal that distinct microbial Hyl variants uniquely shape host–microbe interactions and disease outcomes. This review focuses on microbial Hyls, specifically bacterial Hyls, emphasizing their roles in host immune regulation and inflammatory diseases, particularly in Cutibacterium acnes-mediated acne pathogenesis. We also discuss emerging therapeutic strategies targeting the HA-Hyl axis to modulate inflammation, highlighting their potential as a foundation for novel human therapeutics. Full article

The growing emphasis on sustainability, regional distinctiveness, and spontaneous fermentation in winemaking necessitates a more comprehensive understanding of local yeast populations and their functional mechanisms. In total, 115 indigenous yeast strains were examined for their enzymatic activities of potential vitivinicultural significance. The yeasts were screened for chitinase activity (biocontrol potential), glycosidase activity (terpene release), β-lyases (thiol release), and sulfite reductases (off-flavor formation), followed by quantitative analysis of the selected subsets. Yeasts were further evaluated for inhibition of fungal mycelial growth, VOC-mediated inhibition, and tolerance to commonly applied fungicides. Pre-field selection was refined using the niche overlap index and grapevine leaf disc assay. The results confirmed chitinolytic activity in four species; all strains exhibited hydrolase activities, with H. uvarum 116 displaying the highest cell-associated activity (6.32 U/g), while T. delbrueckii Sut94 showed the highest extracellular activity (1.36 U/g). β-glucosidase and β-lyase activities were widespread, whereas hydrogen sulfide production was infrequent. P. guilliermondii ZIM 624 showed the most comprehensive overall enzymatic profile, together with strong inhibition patterns. A field trial on Pinot cultivars (V. vinifera L.) further evaluated P. guilliermondii ZIM 624 within an integrated disease management approach, with responses being more pronounced in ‘Pinot noir’ than in ‘Pinot gris’. Full article

Initially characterized as a component of the extracellular matrix (ECM) in cartilage, cartilage intermediate layer protein 2 (CILP2) is now recognized as a pleiotropic secretory protein with far-reaching roles in physiology and disease. This review synthesizes evidence establishing CILP2 as a key modulator at the nexus of metabolic dysfunction, cancer, and other pathologies. Genomic studies have firmly established the NCAN-CILP2 locus as a hotspot for genetic variants influencing dyslipidemia and cardiovascular risk. Functionally, CILP2 is upregulated by metabolic stress, including high glucose and oxidatively modified LDL (oxLDL), and actively contributes to pathologies such as dyslipidemia, diabetes, and sarcopenia by impairing glucose metabolism and mitochondrial function. Its role extends to fibrosis and neurodevelopment, promoting hypertrophic scar formation and neurogenesis through interactions with ATP citrate lyase (ACLY) and Wnt3a, respectively. More recently, CILP2 has emerged as an oncoprotein, overexpressed in multiple cancers, including pancreatic ductal adenocarcinoma and colorectal cancer. It drives tumor proliferation and metastasis and correlates with tumor microenvironment remodeling through mechanisms involving Akt/EMT signaling and immune infiltration. The dysregulation of CILP2 in patient serum and its correlation with disease severity and poor prognosis highlight it as a promising biomarker and a compelling therapeutic target across a spectrum of human diseases. Full article

Arsenic (As) toxicity drives the evolution of resistance mechanisms in environmental microorganisms. Bacteria of the Bacillus genus are frequently identified in isolates from arsenic-contaminated sites, highlighting the importance of understanding the molecular mechanisms related to this bacterial genus. Bacillus subtilis, a soil microorganism and Gram-positive model paradigm, employs multiple strategies to counteract As toxicity, including biosorption, redox transformation, active efflux, and inducible genetic regulation. This review provides a comprehensive analysis of the physiological and molecular mechanisms involved in arsenic response in B. subtilis and related species, focusing on the ars and ase operons. The ars operon, located within the mobile SKIN element, encodes a reductase (ArsC), an Acr3-type efflux pump (ArsB), a carbon–arsenic lyase (ArsI/YqcK), and a transcriptional repressor (ArsR), all co-regulated in response to arsenic. In turn, the ase operon contributes to resistance via an ArsB-type efflux system (AseA) and its own regulatory protein (AseR) but lacks an arsenate reductase. Additionally, genes such as aioAB, arrAB, and arsD are discussed, along with evidence for extracellular detoxification and cell surface immobilization of As. Studies on environmental Bacillus species are examined, pointing out the evolutionary implications of As resistance and the biotechnological potential for remediation of contaminated sites. Full article

Vibrio sp. is one of the main producers of alginate lyase; however, most strains have problems such as low and unstable enzyme production. In this study, the enzyme production conditions of V. sp. 32415, a marine bacterium capable of producing extracellular alginate lyase, were optimized through Response Surface Design. The optimized medium was as follows: NaCl 12 g/L, FeSO₄·7H₂O 0.067 g/L, NH₄Cl 7 g/L, alginate 11 g/L, K₂HPO₄·3H₂O 4 g/L, MgSO₄·7H₂O 1 g/L. Under 28 °C, 160 rpm, 30 mL/300 mL liquid volume, and an initial pH 5.5 culture condition, the extracellular enzyme activity was 51.06 U/mL, which was 2.8 times higher compared with the activity before optimization. The optimal temperature, pH, and NaCl concentration for the extracellular alginate lyase were 37 °C, 8.0, and 0.1 M, respectively. The enzyme remained more than 80% of its original activity at 30 °C for 4 h. 1 mM Fe³⁺, Ca²⁺, K⁺, Mg²⁺, and Na⁺ enhance enzyme activity, with a preference for polyG blocks. V. sp. 32415 has two circular chromosomes and one circular plasmid. Chromosome 2 has two polysaccharide utilization loci. It utilizes alginate through the Scatter pathway. The results of this study provide theoretical and data support for understanding the production of extracellular alginate lyase by marine Vibrio and their metabolism and utilization of alginate. Full article

Extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitors show therapeutic potential in triple-negative breast cancer (TNBC), but resistance through compensatory signaling limits their efficacy. We previously identified the secretory carrier membrane protein 3 (SCAMP3) as a regulator of TNBC progression and ERK1/2 activation. Here, we investigated the role of SCAMP3 in ERK1/2 signaling and therapeutic response using TMT-based LC-MS/MS phosphoproteomics of wild-type (WT) and SCAMP3 knockout (SC3KO) SUM-149 cells under basal conditions, after epidermal growth factor (EGF) stimulation, and during ERK1/2 inhibition with MK-8353. A total of 4408 phosphosites were quantified, with 1093 significantly changed. SC3KO abolished residual ERK activity under MK-8353 and affected the compensatory activation of oncogenic pathways observed in WT cells. SC3KO reduced the phosphorylation of ERK feedback regulators RAF proto-oncogene serine/threonine-protein kinase Raf-1 (S43) and the dual-specificity mitogen-activated protein kinase kinase 2 (MEK2) (T394), affected other ERK targets, including nucleoporins, transcription factors, and metabolic enzymes triosephosphate isomerase (TPI1) (S21) and ATP-citrate lyase (ACLY) (S455). SCAMP3 loss also impaired the mammalian target of rapamycin complex I (mTORC1) signaling and disrupted autophagic flux, evidenced by elevated sequestosome-1 (SQSTM1/p62) and microtubule-associated protein light chain 3 (LC3B-II) with reduced levels of the autophagosome lysosome maturation marker, Rab7A. Beyond ERK substrates, SC3KO affected phosphorylation events mediated by other kinases. These findings position SCAMP3 as a central coordinator of ERK signaling and autophagy. Our results support SCAMP3 as a potential therapeutic target to enhance ERK1/2 inhibitor clinical efficacy and overcome adaptive resistance mechanisms in TNBC. Full article

Different types of microRNA participate in the post-transcriptional regulation of target genes. The content of several hypoxia-dependent miRNAs in plant cells, including miR775, increases in the conditions of oxygen deficiency. Electrophoretic studies of total RNA samples from the leaves of flooded seedlings of maize (Zea mays L.) revealed the presence of two interfering complexes with miR775 at 12 h of hypoxic incubation. A nucleotide sequence analysis of a sample containing the interfering complex of miR775 with mRNA from maize leaves showed a high degree of homology with the ICL/PEPM_KPHMT lyase family domain. It corresponded to a fragment of fructose-1,6-bisphosphate aldolase mRNA. By real-time PCR, we established the dynamics of the content of transcripts of aldolase isoenzyme genes under hypoxia in maize leaves. A decrease in the transcriptional activity of the aldolase 1 gene (Aldo1) correlated with a high content of miR775 in maize leaf cells. The fraction of extracellular vesicles sedimented at 100,000× g, was enriched with miR775. The accumulation of aldolase 2 (Aldo2) mRNA transcripts under hypoxic conditions indicates its participation in maintaining glycolysis when Aldo1 expression is inhibited. We conclude that an increase in the total content of free miR775 and its participation in the suppression of the Aldo1 gene represents an important mechanism in developing the adaptive reaction of cellular metabolism in response to hypoxia. Full article

This research introduced a strategy to fabricate sub-millimeter-diameter artificial liver tissue by extruding a combination of a liver decellularized extracellular matrix (dECM), alginate, endothelial cells, and hepatocytes. Vascularization remains a critical challenge in liver tissue engineering, as replicating the liver’s intricate vascular network is essential for sustaining cellular function and viability. Seven scaffold groups were evaluated, incorporating different cell compositions, scaffold materials, and structural configurations. The hepatocyte and endothelial cell scaffold treated with alginate lyase demonstrated the highest diffusion rate, along with enhanced albumin secretion (2.8 µg/mL) and urea synthesis (220 µg/mL) during the same period by day 10. A dense and interconnected endothelial cell network was observed as early as day 4 in the lyased coculture group. Furthermore, three-week implantation studies in rats showed a stable integration to the host with no adverse effects. This approach offers significant potential for advancing functional liver tissue replacements, combining accelerated diffusion, enhanced albumin secretion, improved urea synthesis, dense vascular network formation, and stable implantation outcomes. Full article

Isorhamnetin (ISO) is an active flavonoid compound mainly isolated from the fruits of Hippophae rhamnoides L. and the leaves of Ginkgo biloba L. Previous studies have revealed the antifibrotic action of ISO in the liver and lungs, although its potential protective effects against renal fibrosis and the underlying mechanisms are still poorly understood. Given that many actions of ISO could be similarly attained by hydrogen sulfide (H₂S), we speculated that ISO may work through the induction of endogenous H₂S. To test the hypothesis, we established the unilateral ureteral obstruction (UUO) renal fibrosis rat model and transforming growth factor-β1(TGF-β1)-induced fibrosis in cultured renal tubular cells. ISO treatment inhibited epithelial–mesenchymal transition (EMT) formation, decreased extracellular matrix (ECM) deposition, and relieved renal fibrosis. Further analysis revealed that ISO stimulated the expression of the H₂S-synthesizing enzyme cystathionine lyase (CSE) and cystathionine beta-synthase (CBS), and promoted H₂S production in vivo and in vitro. The elevated H₂S attenuated oxidative stress and elevated the thiol level. It induced Keap1 sulfhydration, disrupted Keap1-Nrf2 interaction, and promoted the entry of Nrf2 into the nucleus. Finally, we found that circulating H₂S mainly derived from the liver, and not the kidney. Collectively, our study revealed that ISO alleviated renal fibrosis by inducing endogenous H₂S and regulating Keap1-Nrf2 interaction through sulfhydration of Keap1. Endogenous H₂S could be an important mediator underlying the pharmacological actions of ISO. Due to the multifunctional properties of H₂S, the H₂S-inducing nature of ISO could be exploited to treat various diseases. Full article

Alginate lyase is an attractive biocatalyst that can specifically degrade alginate to produce oligosaccharides, showing great potential for industrial and medicinal applications. Herein, an alginate-degrading strain HB236076 was isolated from Sargassum sp. in Qionghai, Hainan, China. The low 16S rRNA gene sequence identity (<98.4%), ANI value (<71.9%), and dDDH value (<23.9%) clearly indicated that the isolate represented a potential novel species of the genus Vibrio. The genome contained two chromosomes with lengths of 3,007,948 bp and 874,895 bp, respectively, totaling 3,882,843 bp with a G+C content of 46.5%. Among 3482 genes, 3332 protein-coding genes, 116 tRNA, and 34 rRNA sequences were predicted. Analysis of the amino acid sequences showed that the strain encoded 73 carbohydrate-active enzymes (CAZymes), predicting seven PL7 (Alg1–7) and two PL17 family (Alg8, 9) alginate lyases. The extracellular alginate lyase from strain HB236076 showed the maximum activity at 50 °C and pH 7.0, with over 90% activity measured in the range of 30–60 °C and pH 6.0–10.0, exhibiting a wide range of temperature and pH activities. The enzyme also remained at more than 90% of the original activity at a wide pH range (3.0–9.0) and temperature below 50 °C for more than 2 h, demonstrating significant thermal and pH stabilities. Fe²⁺ had a good promoting effect on the alginate lyase activity at 10 mM, increasing by 3.5 times. Thin layer chromatography (TLC) and electrospray ionization mass spectrometry (ESI-MS) analyses suggested that alginate lyase in fermentation broth could catalyze sodium alginate to produce disaccharides and trisaccharides, which showed antimicrobial activity against Shigella dysenteriae, Aeromonas hydrophila, Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli. This research provided extended insights into the production mechanism of alginate lyase from Vibrio sp. HB236076, which was beneficial for further application in the preparation of pH-stable and thermo-stable alginate lyase and alginate oligosaccharides. Full article

The N-terminal sequences of proteins and their corresponding encoding sequences may play crucial roles in the heterologous expression. In this study, the secretory expression of alkaline pectin lyase APL in B. subtilis was investigated to explore the effects of the N-terminal 5–7 amino acid sequences of different signal peptides on the protein expression and secretion. It was identified for the first time that the first five amino acid sequences of the N-terminal of the signal peptide (SP^-LipA) from Bacillus subtilis lipase A play an important role in promoting the expression of APL. Furthermore, it was revealed that SP^-LipA resulted in higher secretory expression compared to other signal peptides in this study primarily due to its encoding of N-terminal amino acids with relatively higher transcription levels and its efficient secretion capacity. Based on this foundation, the recombinant strain constructed in this work achieved a new record for the highest extracellular yields of APL in B. subtilis, reaching 12,295 U/mL, which was 1.9-times higher than that expressed in the recombinant Escherichia coli strain previously reported. The novel theories uncovered in this study are expected to play significant roles in enhancing the expression of foreign proteins both inside and outside of cells. Full article

Alginate oligosaccharides (AOS), products of alginate degradation by endotype alginate lyases, possess favorable biological activities and have broad applications. Although many have been reported, alginate lyases with homogeneous AOS products and secretory production by an engineered host are scarce. Herein, the alginate lyase AlyC7 from Vibrio sp. C42 was characterized as a trisaccharide-producing lyase exhibiting high activity and broad substrate specificity. With PelB as the signal peptide and 500 mM glycine as the additive, the extracellular production of AlyC7 in Escherichia coli reached 1122.8 U/mL after 27 h cultivation in Luria-Bertani medium. The yield of trisaccharides from sodium alginate degradation by the produced AlyC7 reached 758.6 mg/g, with a purity of 85.1%. The prepared AOS at 20 μg/mL increased the root length of lettuce, tomato, wheat, and maize by 27.5%, 25.7%, 9.7%, and 11.1%, respectively. This study establishes a robust foundation for the industrial and agricultural applications of AlyC7. Full article