Search Results (555)

The paper investigates the process of degumming substandard soybean oil using an enzyme complex of phospholipases to prepare it as a feedstock for biodiesel production. Dehumidification is an important refining step aimed at reducing the phosphorus content, which exceeds the permissible limits according to ASTM, EN, and ISO standards, by re-moving phospholipids. The enzyme complex of phospholipases includes phospholipase C, which specifically targets phosphatidylinositol, and phospholipase A2, which catalyzes the hydrolysis of phospholipids into water-soluble phosphates and lysophospholipids. This process contributes to the efficient removal of phospholipids, increased neutral oil yield, and reduced residual oil in the humic phase. The use of an enzyme complex of phospholipases provides an innovative, cost-effective, and environmentally friendly method of oil purification. The results of the study demonstrate the high efficiency of using the phospholipase enzyme complex in the processing of substandard soybean oil, which allows reducing the content of total phosphorus to 0.001% by weight, turning it into a high-quality raw material for biodiesel production. The proposed approach contributes to increasing the profitability of agricultural raw materials and the introduction of environmentally friendly technologies in the field of renewable energy. Full article

Snakebite remains the most neglected tropical disease globally, with India experiencing the highest rates of mortality and morbidity. While most envenomation cases in India are attributed to the ‘big four’ snakes, research has predominantly focused on Russell’s viper (Daboia russelii), spectacled cobra (Naja naja), and common krait (Bungarus caeruleus), leading to a considerable gap in our understanding of saw-scaled viper (Echis carinatus carinatus) venoms. For instance, the venom gland transcriptome and inter- and intra-population venom variation in E. c. carinatus have largely remained uninvestigated. A single study to date has assessed the effectiveness of commercial antivenoms against this species under in vivo conditions. To address these crucial knowledge gaps, we conducted a detailed investigation of E. c. carinatus venom and reported the first venom gland transcriptome. A proteotranscriptomic evaluation revealed snake venom metalloproteinases, C-type lectins, L-amino acid oxidases, phospholipase A₂s, and snake venom serine proteases as the major toxins. Moreover, we assessed the intra-population venom variation in this species using an array of biochemical analyses. Finally, we determined the venom toxicity and the neutralising efficacy of a commercial antivenom using a murine model of snake envenoming. Our results provide a thorough molecular and functional profile of E. c. carinatus venom. Full article

In the marine red alga Pyropia yezoensis, filamentous phases of the life cycle, e.g., the conchocelis (sporophyte) and conchosporangium (conchosporophyte), proliferate by tip growth. In this study, we investigated the possible involvement of phosphoinositide turnover and actin polymerization in the spontaneous initiation and tip growth of new branches in isolated single-celled conchocelis cells using pharmacological treatments. Treatment with LY294002 and U73122, specific inhibitors of phosphoinositide-phosphate 3-kinase and phospholipase C, respectively, reduced side-branch formation and inhibited the elongation of branches. In addition, two inhibitors of the actin cytoskeleton, cytochalasin B (CCB) and latrunculin B (LAT-B), had similar effects on tip growth. However, CCB did not alter the branching rate of single-celled conchocelis, whereas LAT-B did. As CCB and LAT-B affect actin polymerization through different mechanisms, this result suggests differences in the contributions of actin polymerization to branch initiation versus tip growth. These findings demonstrate the critical and diverse functional roles played by phosphoinositide turnover and actin polymerization in the regulation of the initiation and maintenance of tip growth in the conchocelis phase of P. yezoensis. Full article

Background: Snake envenomation is a major public health issue in Nigeria, primarily due to bites from Echis ocellatus, Naja nigricollis, and Bitis arietans. Understanding their venom composition is essential for effective antivenom development. This study characterizes and compares the venom proteomes of these snakes using iTRAQ-based proteomics, focusing on key toxin families and their relative abundances. Methods: Venom samples were ethically collected from adult snakes, pooled by species, lyophilized, and stored for proteomic analysis. Proteins were extracted, digested with trypsin, and labeled with iTRAQ. Peptides were analyzed via mass spectrometry, and data were processed using Mascot and IQuant for protein identification and quantification. Results: E. ocellatus and B. arietans venoms had similar profiles, rich in C-type lectins, serine proteases, and phospholipase A₂s. These comprised 17%, 11%, and 5% in E. ocellatus and 47%, 10%, and 7% in B. arietans, with metalloproteinases dominating both (53% and 47%). In N. nigricollis, three-finger toxins (9%) were most abundant, followed by metalloproteinases (3%). All species shared four core protein families, with N. nigricollis also containing four uncharacterized proteins. Conclusions: This study highlights venom compositional differences, advancing snake venom biology and informing targeted antivenom development. Full article

Mammalian fertilization is triggered by a series of calcium (Ca²⁺) oscillations that are essential for egg activation and successful embryo development. It is widely accepted that Phospholipase C zeta (PLCζ) is the sperm-derived factor that triggers these oscillations, initiating egg activation through the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP₂) into inositol 1,4,5-trisphosphate (IP₃) and diacylglycerol (DAG), leading to Ca²⁺ release. Several studies have reported a number of PLCζ mutations associated with polyspermy, egg activation failure and early embryonic arrest. Herein, six infertility-linked PLCζ mutations (I120M, L246F, L277P, S350P, A384V and M578T) spanning different domains of PLCζ were selected for characterization through in vivo assessment of their Ca²⁺-oscillation-inducing activities and complementary in silico analysis. Our data revealed that five of the investigated PLCζ mutants exhibited reduced or complete loss of in vivo Ca²⁺-oscillation-inducing activity, with the exception of the L277P, which resulted in increased frequency and duration of Ca²⁺ oscillations. Molecular modeling of PLCζ mutants was consistent with the in vivo characterization, revealing that most mutations have a deleterious effect on the structural stability. For the first time, we provide evidence that a gain-of-function PLCζ mutation may be a cause of fertilization failure in humans. Our findings suggest that PLCζ enzymatic activity must operate within an optimal range to ensure successful egg activation and early embryonic development. Additionally, we demonstrate the essential role of all PLCζ domains in maintaining the Ca²⁺ oscillation-inducing activity in eggs and the importance of PLCζ functionality in human fertilization. Full article

Background/Objectives: Chronic inflammation is recognized as an important risk factor for a variety of health disorders. Omega-6 polyunsaturated fatty acids (n-6 PUFAs), particularly linoleic (LA) and arachidonic acid (AA), have been shown to be either pro- or anti-inflammatory, and researchers have advocated both for and against reducing their dietary intake. This study sought to correlate the levels of ten inflammation-related biomarkers across multiple pathways with red blood cell (RBC) membrane levels of the major dietary and circulating n-6 PUFAs. Methods: We included 2777 participants (mean age: 66 ± 9 years, 54% women, 9.8% minorities) from the Framingham Offspring and minority-enriched Omni cohorts, and calculated partial correlation coefficients. Results: After multivariable adjustment, RBC LA was inversely correlated (all p ≤ 0.05) with five markers of inflammation, receptors, or pathways: C-reactive protein (r = −0.06); soluble interleukin-6 (r = −0.15); intercellular adhesion molecule-1 (r = −0.09); monocyte chemoattractant protein-1 (r = −0.07); and P-selectin (r = −0.07). RBC AA was inversely correlated (all p ≤ 0.05) with soluble interleukin-6 (r = −0.10); intercellular adhesion molecule-1 (r = −0.14); monocyte chemoattractant protein-1, and (r = −0.06); and osteoprotegerin (r = −0.07). Lipoprotein-associated phospholipase-A2 mass and activity, urinary isoprostanes, and tumor necrosis factor receptor-2 were not significantly correlated with LA or AA. Conclusions: In our large community-based study, we observed weak but statistically significant inverse associations between several types of inflammatory biomarkers with RBC n-6 PUFAs. Our findings do not support the hypothesis that omega-6 fatty acids are pro-inflammatory. Full article

Invasive fungal infections (IFIs), primarily caused by Candida species, represent a significant global public health concern due to their high mortality rates and growing antifungal resistance. In Honduras, data on their epidemiology remains scarce. This study aimed to characterize Candida species associated with candidemia and assess key virulence factors. A total of 80 clinical isolates were collected from four hospitals in Honduras’s major cities, Tegucigalpa and San Pedro Sula. Identification was performed using both phenotypic and molecular methods. Hemolytic activity, phospholipase and protease production, and biofilm formation were evaluated. C. albicans and C. tropicalis were the most prevalent species (30% each), followed by C. parapsilosis (27.5%). Phenotypic methods misidentified 13.8% of the isolates. Most strains (96.3%) exhibited strong hemolytic activity. C. albicans showed the highest phospholipase activity, while C. tropicalis was the most robust film producer. These findings highlight an evolving epidemiological landscape characterized by an increasing prevalence of non-albicans Candida species, often less susceptible to antifungal agents, and diverse virulence profiles such as strong biofilm formation. This underscores the clinical need for accurate species-level identification through molecular diagnostics and ongoing surveillance to guide targeted antifungal therapy and enable early, locally adapted interventions. Full article

Synbiotics can be used to reduce intestinal inflammation and mitigate dysbiosis in dogs with chronic inflammatory enteropathy (CIE). Prior research has not assessed the colonic mucosal ultrastructure of dogs with active CIE treated with synbiotics, nor has it determined a possible association between morphologic injury and signaling pathways. Twenty client-owned dogs diagnosed with CIE were randomized to receive either a hydrolyzed diet (placebo; PL) or a hydrolyzed diet supplemented with synbiotic-IgY (SYN) for 6 weeks. Endoscopic biopsies of the colon were obtained for histopathologic, ultrastructural, and molecular analyses and were compared before and after treatment. Using transmission electron microscopy (TEM), an analysis of the ultrastructural alterations in microvilli length (MVL), mitochondria (MITO), and rough endoplasmic reticulum (ER) was compared between treatment groups. To explore potential signaling pathways that might modulate MITO and ER stress, a transcriptomic analysis was also performed. The degree of mucosal ultrastructural pathology differed among individual dogs before and after treatment. Morphologic alterations in enterocytes, MVL, MITO, and ER were detected without significant differences between PL and SYN dogs prior to treatment. Notable changes in ultrastructural alterations were identified post-treatment, with SYN-treated dogs exhibiting significant improvement in MVL, MITO, and ER injury scores compared to PL-treated dogs. Transcriptomic profiling showed many pathways and key genes to be associated with MITO and ER injury. Multiple signaling pathways and their associated genes with protective effects, including fibroblast growth factor 2 (FGF2), fibroblast growth factor 7 (FGF7), fibroblast growth factor 10 (FGF10), synaptic Ras GTPase activating protein 1 (SynGAP1), RAS guanyl releasing protein 2 (RASGRP2), RAS guanyl releasing protein 3 (RASGRP3), thrombospondin 1 (THBS1), colony stimulating factor 1 (CSF1), colony stimulating factor 3 (CSF3), interleukin 21 receptor (IL21R), collagen type VI alpha 6 chain (COL6A6), ectodysplasin A receptor (EDAR), forkhead box P3 (FoxP3), follistatin (FST), gremlin 1 (GREM1), myocyte enhancer factor 2B (MEF2B), neuregulin 1 (NRG1), collagen type I alpha 1 chain (COL1A1), hepatocyte growth factor (HGF), 5-hydroxytryptamine receptor 7 (HTR7), and platelet derived growth factor receptor beta (PDGFR-β), were upregulated with SYN treatment. Differential gene expression was associated with improved MITO and ER ultrastructural integrity and a reduction in oxidative stress. Conversely, other genes, such as protein kinase cAMP-activated catalytic subunit beta (PRKACB), phospholipase A2 group XIIB (PLA2G12B), calmodulin 1 (CALM1), calmodulin 2 (CALM2), and interleukin-18 (IL18), which have harmful effects, were downregulated following SYN treatment. In dogs treated with PL, genes including PRKACB and CALM2 were upregulated, while other genes, such as FGF2, FGF10, SynGAP1, RASGRP2, RASGRP3, and IL21R, were downregulated. Dogs with CIE have colonic ultrastructural pathology at diagnosis, which improves following synbiotic treatment. Ultrastructural improvement is associated with an upregulation of protective genes and a downregulation of harmful genes that mediate their effects through multiple signaling pathways. Full article

Temperature is perceived primarily via transient receptor potential (TRP) channels, which are integral to the molecular machinery sensing environmental and cellular signals. Functional evidence of TRP channels’ involvement in regulating cold-induced developmental/reproductive responses remains scarce. Here, we show that mutations affecting cold-sensing TRP channels antagonize the reduction in ovarian development induced by low temperatures (reproductive dormancy) in Drosophila melanogaster. More specifically, mutants for brv1, trp, and trpl significantly lowered dormancy levels at 12 °C and exhibited well-developed oocytes characterized by advanced vitellogenesis. Similarly, functional knockouts for norpA, a gene encoding a phospholipase C acting downstream to Trp and Trpl, exhibited a reduced dormancy response, suggesting that Ca²⁺ signaling is key to relaying cold-sensing stimuli during dormancy induction and maintenance. Finally, mutants with an altered temperature preference (i.e., exhibiting impaired cold or warm avoidance) differentially responded to the cold, either lowering or increasing dormancy levels. In summary, our phenotypic analysis provides functional evidence of developmental/reproductive modulation by specific cold-sensing TRP channels in Drosophila melanogaster and indicates that temperature preference affects developmental processes. Full article

An experimental model of acute pulmonary damage was developed based on the intravenous injection of the phospholipase A₂ (PLA₂)-rich venom of Pseudechis papuanus (Papuan black snake) in mice. Venom caused pulmonary edema, with the accumulation of a protein-rich exudate, as observed histologically and by analysis of bronchoalveolar lavage fluid (BALF). In parallel, venom induced an increase in all of the pulmonary mechanical parameters evaluated, without causing major effects in terms of tracheal and bronchial reactivity. These effects were abrogated by incubating the venom with the PLA₂ inhibitor varespladib, indicating that this hydrolytic enzyme is responsible for these alterations. The venom was cytotoxic to endothelial cells in culture, hydrolyzed phospholipids of a pulmonary surfactant, and reduced the activity of angiotensin-converting enzyme in the lungs. The pretreatment of mice with the nitric oxide synthase inhibitor L-NAME reduced the protein concentration in the BALF, whereas no effect was observed when mice were pretreated with inhibitors of cyclooxygenase (COX), tumor necrosis factor-α (TNF-α), bradykinin, or neutrophils. Based on these findings, it is proposed that the rapid pathological effect of this venom in the lungs is mediated by (a) the direct cytotoxicity of venom PLA₂ on cells of the capillary–alveolar barrier, (b) the degradation of surfactant factor by PLA₂, (c) the deleterious action of nitric oxide in pulmonary tissue, and (d) the cytotoxic action of free hemoglobin that accumulates in the lungs as a consequence of venom-induced intravascular hemolysis. Our findings offer clues on the mechanisms of pathophysiological alterations induced by PLA₂s in a variety of pulmonary diseases, including acute respiratory distress syndrome (ARDS). Full article

The Phosphoinositide Specific-Phospholipase C (PI-PLC) family of enzymes plays a crucial role in various cellular processes by catalyzing the hydrolysis of phosphatidylinositol 4,5-bisphosphate [PI(4,5)P₂] into inositol 1,4,5-trisphosphate (IP₃) and diacylglycerol (DAG), which are essential messengers mediating critical intracellular signaling pathways. Herein, we carry out a comprehensive analysis of the structure, function, regulation, and implications of the PI-PLC family enzymes in both physiological and pathological contexts. More specifically, we discuss the structural features of PI-PLCs, elucidating their conserved domains and catalytic mechanisms. Furthermore, we explore the multifaceted roles of PI-PLCs in signal transduction, cellular homeostasis, and membrane dynamics, whilst highlighting the intricate regulatory mechanisms governing their activity such as protein–protein interactions, post-translational modifications, and lipid modulation. Lastly, we assess the involvement of PI-PLCs in various diseases, such as cancer, neurological disorders, immune dysregulation, and male infertility, emphasizing their potential as therapeutic targets. Full article

Background/Objectives: Timely and effective clinical management of leishmaniasis depends on a deep understanding of parasite biology and drug resistance mechanisms. Phosphatidylinositol-specific phospholipase C (PI-PLC) enzymes are critical for parasite survival and immune evasion and possibly influence treatment outcomes. This study aimed to characterize the PI-PLC gene family in the Leishmania infantum and Leishmania major genomes, with a focus on their expression profiles in antimony-susceptible and -resistant strains to uncover their diagnostic and prognostic relevance. Methods: This study conducted a comprehensive genome-wide screening to identify PI-PLC genes in L. infantum and L. major, followed by detailed analyses of their gene structures, conserved motifs, chromosomal localization, and phylogenetic relationships. To explore potential roles in drug resistance and clinical prognosis, RNA-seq data from antimony-resistant and -susceptible L. infantum strains were analyzed for differential gene expression. Results: Twenty-two PI-PLC genes were identified in each species, displaying conserved catalytic domains and diverse biochemical characteristics. Phylogenetic and chromosomal analyses revealed gene clustering and distribution patterns. Importantly, expression profiling highlighted several PI-PLC genes with differential regulation in resistant strains, suggesting a role in treatment response and potential as molecular markers. Conclusions: Our findings suggest that PI-PLC genes may be associated with drug susceptibility in L. infantum, warranting further functional investigation to validate their role as potential molecular markers. Full article

Phospholipase C zeta (PLCζ) has emerged as a pivotal sperm-specific factor responsible for triggering oocyte activation, a process essential for successful fertilization and early embryogenesis. A narrative review was conducted to examine the molecular architecture and biochemical features of PLCζ, with particular emphasis on how its distinctive structural domains facilitate the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP₂) and the induction of calcium (Ca²⁺) oscillations in the oocyte. Notably, PLCζ exhibits unique sensitivity to basal Ca²⁺ levels and the capacity to sustain repetitive intracellular Ca²⁺ transients that drive meiotic progression and block polyspermy. Clinically, PLCζ deficiency—whether caused by genetic mutations, reduced expression, or improper localization—represents a unifying explanation for certain forms of male infertility, including total fertilization failure (TFF) following intracytoplasmic sperm injection (ICSI). Globozoospermia is a prime example; this condition is characterized by round-headed sperm devoid of acrosomes and exhibiting significantly reduced or absent PLCζ and often results in fertilization failure. Diagnostic methods such as immunofluorescence, Western blotting, and the mouse oocyte-activation test collectively support the identification and characterization of PLCζ-related defects, while genetic testing for mutations in the PLCZ1 gene has proven valuable for identifying hereditary causes of sperm-borne oocyte-activation deficiency (OAD). Therapeutic approaches range from assisted oocyte activation (AOA) with calcium ionophores to emerging interventions that introduce functional PLCζ protein or mRNA directly into the oocyte. These advancements demonstrate the rapid translation of foundational discoveries into clinically actionable interventions. Future investigations are poised to refine diagnostic assays, standardize measurement protocols, and explore the potential of gene therapy or CRISPR/Cas9-mediated correction for heritable PLCζ abnormalities. By addressing both the molecular basis and translational applications of PLCζ, recent findings underscore its indispensable role in fertility care and lay out a path toward further innovation in assisted reproductive technologies. Full article

Wounding triggers complex secondary metabolic pathways in plants, including benzylisoquinoline alkaloid (BIA) biosynthesis in opium poppy (Papaver somniferum L.). This study explores transcriptional and metabolic responses to wounding and methyl jasmonate (MeJA) treatment, focusing on BIA biosynthesis and regulatory mechanisms. Real-time expression analysis revealed significant up-regulation of transcripts in the (S)-reticuline and papaverine biosynthetic pathway, while the noscapine pathway was suppressed. The morphinan pathway also showed transcriptional activation, except in the case of codeinone reductase (COR), which remained unresponsive to both wounding and MeJA, suggesting a partially uncoupled mechanism. Metabolite profiling using HPLC-MS demonstrated a rapid accumulation of morphine post wounding, further supporting the hypothesis of independent regulatory control over COR. The role of phospholipase C (PLC) in modulating wound-induced BIA accumulation was investigated, revealing that PLC inhibition reduced morphine production and suppressed COR expression. These findings highlight the importance of phospholipid-dependent signalling in activating morphine biosynthesis, potentially at the expense of other BIAs. This study provides insights into plant stress responses and suggests strategies for enhancing BIA production through targeted interventions, offering potential applications in improving alkaloid yield. Full article

Vulvovaginal candidiasis (VVC) is an opportunistic mycosis that affects women of reproductive age. The most frequent etiological agent is Candida albicans. The development of VVC depends on factors related to the host and the fungus. Among the factors related to Candida spp. are virulence factors, but genotype may also be involved. The objective of this study was to evaluate the ABC genotypes and extracellular hydrolytic enzyme production in C. albicans isolates obtained from Mexican women with vulvovaginitis to determine if there is a correlation between these characteristics that allows the fungus to invade and cause damage to the host. Forty-three yeast isolates were obtained from vaginal exudates from women with symptoms of infection. The isolates were identified by germ tube tests and by Cand PCR. The ABC genotype of the isolates identified as C. albicans was determined through the isolates’ DNA amplification using the oligonucleotides CA-INT-R and CA-INT-L. The activity of esterase, phospholipase, proteinase, and hemolysin was evaluated in specific culture media. The correlation between extracellular enzyme production and genotype was analyzed using a two-way ANOVA and the Sidak comparison test. A total of 57.5% of the yeast isolates were identified as C. albicans. The genotypes identified were A (82.6%) and B (17.4%). The activity of esterase, phospholipase, proteinase, and hemolysin was very strong. No statistically significant difference was found between enzyme production and genotypes. In conclusion, genotype A predominates among C. albicans vaginal isolates. The production of extracellular hydrolytic enzymes was widely expressed in C. albicans vaginal isolates, but no correlation with genotype was found. Full article