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Molecular Plant Pathology Jul 2024A cell death pathway, ferroptosis, occurs in conidial cells and is critical for formation and function of the infection structure, the appressorium, in the rice blast...
A cell death pathway, ferroptosis, occurs in conidial cells and is critical for formation and function of the infection structure, the appressorium, in the rice blast fungus Magnaporthe oryzae. In this study, we identified an orthologous lysophosphatidic acid acyltransferase (Lpaat) acting at upstream of phosphatidylethanolamines (PEs) biosynthesis and which is required for such fungal ferroptosis and pathogenicity. Two PE species, DOPE and SLPE, that depend on Lpaat function for production were sufficient for induction of lipid peroxidation and the consequent ferroptosis, thus positively regulating fungal pathogenicity. On the other hand, both DOPE and SLPE positively regulated autophagy. Loss of the LPAAT gene led to a decrease in the lipidated form of the autophagy protein Atg8, which is probably responsible for the autophagy defect of the lpaatΔ mutant. GFP-Lpaat was mostly localized on the membrane of lipid droplets (LDs) that were stained by the fluorescent dye monodansylpentane (MDH), suggesting that LDs serve as a source of lipids for membrane PE biosynthesis and probably as a membrane source of autophagosome. Overall, our results reveal novel intracellular membrane-bound organelle dynamics based on Lpaat-mediated lipid metabolism, providing a temporal and spatial link of ferroptosis and autophagy.
Topics: Autophagy; Phosphatidylethanolamines; Ferroptosis; Oryza; Plant Diseases; Fungal Proteins; Acyltransferases; Ascomycota
PubMed: 38956897
DOI: 10.1111/mpp.13489 -
Scientific Reports Jul 2024Posttraumatic stress disorder (PTSD) can develop after trauma exposure. Some studies report that women develop PTSD at twice the rate of men, despite greater trauma...
Posttraumatic stress disorder (PTSD) can develop after trauma exposure. Some studies report that women develop PTSD at twice the rate of men, despite greater trauma exposure in men. Lipids and their metabolites (lipidome) regulate a myriad of key biological processes and pathways such as membrane integrity, oxidative stress, and neuroinflammation in the brain by maintaining neuronal connectivity and homeostasis. In this study, we analyzed the lipidome of 40 adults with PTSD and 40 trauma-exposed non-PTSD individuals (n = 20/sex/condition; 19-39 years old). Plasma samples were analyzed for lipidomics using Quadrupole Time-of-Flight (QToF) mass spectrometry. Additionally, ~ 90 measures were collected, on sleep, and mental and physical health indices. Poorer sleep quality was associated with greater PTSD severity in both sexes. The lipidomics analysis identified a total of 348 quantifiable known lipid metabolites and 1951 lipid metabolites that are yet unknown; known metabolites were part of 13 lipid subclasses. After adjusting for BMI and sleep quality, in women with PTSD, only one lipid subclass, phosphatidylethanolamine (PE) was altered, whereas, in men with PTSD, 9 out of 13 subclasses were altered compared to non-PTSD women and men, respectively. Severe PTSD was associated with 22% and 5% of altered lipid metabolites in men and women, respectively. Of the changed metabolites, only 0.5% measures (2 PEs and cholesterol) were common between women and men with PTSD. Several sphingomyelins, PEs, ceramides, and triglycerides were increased in men with severe PTSD. The correlations between triglycerides and ceramide metabolites with cholesterol metabolites and systolic blood pressure were dependent upon sex and PTSD status. Alterations in triglycerides and ceramides are linked with cardiac health and metabolic function in humans. Thus, disturbed sleep and higher body mass may have contributed to changes in the lipidome found in PTSD.
Topics: Humans; Stress Disorders, Post-Traumatic; Male; Female; Adult; Lipidomics; Young Adult; Lipids; Cohort Studies; Lipid Metabolism
PubMed: 38956202
DOI: 10.1038/s41598-024-62971-7 -
Redox Biology Jun 2024Ferroptosis, a lipid peroxidation-driven cell death program kept in check by glutathione peroxidase 4 and endogenous redox cycles, promises access to novel strategies...
Ferroptosis, a lipid peroxidation-driven cell death program kept in check by glutathione peroxidase 4 and endogenous redox cycles, promises access to novel strategies for treating therapy-resistant cancers. Chlorido [N,N'-disalicylidene-1,2-phenylenediamine]iron (III) complexes (SCs) have potent anti-cancer properties by inducing ferroptosis, apoptosis, or necroptosis through still poorly understood molecular mechanisms. Here, we show that SCs preferentially induce ferroptosis over other cell death programs in triple-negative breast cancer cells (LC ≥ 0.07 μM) and are particularly effective against cell lines with acquired invasiveness, chemo- or radioresistance. Redox lipidomics reveals that initiation of cell death is associated with extensive (hydroper)oxidation of arachidonic acid and adrenic acid in membrane phospholipids, specifically phosphatidylethanolamines and phosphatidylinositols, with SCs outperforming established ferroptosis inducers. Mechanistically, SCs effectively catalyze one-electron transfer reactions, likely via a redox cycle involving the reduction of Fe(III) to Fe(II) species and reversible formation of oxo-bridged dimeric complexes, as supported by cyclic voltammetry. As a result, SCs can use hydrogen peroxide to generate organic radicals but not hydroxyl radicals and oxidize membrane phospholipids and (membrane-)protective factors such as NADPH, which is depleted from cells. We conclude that SCs catalyze specific redox reactions that drive membrane peroxidation while interfering with the ability of cells, including therapy-resistant cancer cells, to detoxify phospholipid hydroperoxides.
PubMed: 38955113
DOI: 10.1016/j.redox.2024.103257 -
Antonie Van Leeuwenhoek Jul 2024A Gram-negative, rod-shaped, non-motile, aerobic bacterium, designated as strain TK19101, was isolated from the intermediate seawater of yellow vent in the shallow-sea...
A Gram-negative, rod-shaped, non-motile, aerobic bacterium, designated as strain TK19101, was isolated from the intermediate seawater of yellow vent in the shallow-sea hydrothermal system located near Kueishantao Island. The strain was found to grow at 10-40 °C (optimum, 35 °C), at pH 6.0-8.0 (optimum, 7.0), and in 0-5% (w/v) NaCl (optimum, 1%). Strain TK19101 was catalase-positive and oxidase-positive. The predominant fatty acids (> 10%) in strain TK19101 cells were C, summed feature 8 (C ω6c and/or C ω7c), and C. The predominant isoprenoid quinone of strain TK19101 was ubiquinone-10. The polar lipids of strain TK19101 comprised phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phospholipid, and unknown polar lipid. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain TK19101 belonged to the genus Mesobacterium. Strain TK19101 exhibited highest 16S rRNA gene sequence similarity value to Mesobacterium pallidum MCCC M24557 (97.48%). The estimated average nucleotide identity and digital DNA-DNA hybridization values between strain TK19101 and the closest related species Mesobacterium pallidum MCCC M24557 were 74.88% and 20.30%, respectively. The DNA G + C content was 63.49 mol%. On the basis of the analysis of 16S rRNA gene sequences, genotypic and phylogenetic data, strain TK19101 has a unique phylogenetic status and represents a novel species of genus Mesobacterium, for which the name Mesobacterium hydrothermale sp. nov. is proposed. The type strain is TK19101 (= MCCC 1K08936 = KCTC 8354).
Topics: Phylogeny; RNA, Ribosomal, 16S; Hydrothermal Vents; DNA, Bacterial; Fatty Acids; Seawater; Base Composition; Bacterial Typing Techniques; Islands; Phospholipids; Sequence Analysis, DNA; China
PubMed: 38954062
DOI: 10.1007/s10482-024-01994-6 -
Current Microbiology Jul 2024Two Gram-stain-negative, facultative anaerobic, rod-shaped, motile bacterial strains, designated F26243 and F60267 were isolated from coastal sediment in Weihai, China....
Two Gram-stain-negative, facultative anaerobic, rod-shaped, motile bacterial strains, designated F26243 and F60267 were isolated from coastal sediment in Weihai, China. Strains F26243 and F60267 were grown at 4-40 °C (optimum 33 °C), pH 7.0-9.5 and pH 6.5-9.5 (optimum at pH 7.0), in the presence of 1.0-7.0% (w/v) NaCl (optimum 2.5%) and 1.0-12.0% (w/v) NaCl (optimum 2.0%), respectively. The 16S rRNA gene sequences phylogenetic analysis showed that strains F26243 and F60267 are closely related to the genus Marinobacter and exhibited the highest sequence similarities to Marinobacter salexigens HJR7 (97.7% and 98.0%, respectively), the similarity between two isolates was 96.7%. Strains F26243 and F60267 displayed genomic DNA G + C content of 53.6% and 53.8%, respectively. When compared to the M. salexigens HJR7, the average nucleotide identity (ANI) values were 83.7% and 84.1%, and the percentage of conserved proteins (POCP) values were 79.9% and 84.6%, respectively. Ubiquinone 9 (Q-9) was the only respiratory quinone detected in both isolates. The major cellular fatty acids (> 10.0%) were summed feature 3 (comprising Cω7c and/or Cω6c), C and Cω9c. The polar lipid profiles of strains F26243 and F60267 contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidyldimethylethanolamine, phosphatidylglycerol, aminophospholipid and one unidentified phospholipid. Based on genomic characteristics, phenotypic and chemotaxonomic, strains F26243 and F60267 represent two novel species of the genus Marinobacter, for which the names Marinobacter sediminicola sp. nov. and Marinobacter xiaoshiensis sp. nov. are proposed, the type strains are F26243 (= KCTC 92640 = MCCC 1H01345) and F60267 (= KCTC 92638 = MCCC 1H01346).
Topics: Marinobacter; Geologic Sediments; Phylogeny; RNA, Ribosomal, 16S; Base Composition; Fatty Acids; DNA, Bacterial; China; Bacterial Typing Techniques; Phospholipids; Sequence Analysis, DNA; Seawater
PubMed: 38954028
DOI: 10.1007/s00284-024-03782-x -
Archives of Microbiology Jul 2024Two Gram-staining-negative, facultative anaerobic, rod-shaped and phosphate-solubilizing strains designated SG2303 and SG2305, were isolated from paddy soil in China....
Two Gram-staining-negative, facultative anaerobic, rod-shaped and phosphate-solubilizing strains designated SG2303 and SG2305, were isolated from paddy soil in China. Phylogenetic analysis based on 16 S rRNA gene sequences indicated that SG2303 and SG2305 represented a member of the genus Crenobacter within the family Neisseriaceae of the phylum Pseudomonadota. Strain SG2303 displayed higher 16 S rRNA gene sequence similarities with members of the genus Crenobacter ranging from 93.5 to 94.0%. Strains C. luteus YIM 78141 and C. cavernae K1W11S-77 were closest related to the isolated strains and were considered as type strains. Growth of strain SG2303 occurred at 10-55 °C (optimum 37 °C), pH 5.0-9.0 (optimum pH 6.0-7.0) and 0-1% (w/v) NaCl (optimum 0%). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain SG2303 and its closely related taxa were 76.1-78.2% and 20.5-22.1%, respectively. The genomic DNA G + C content was 62.2%. The quinone of strain SG2303 was Q-8. The major fatty acids (> 10%) of strain SG2303 were C (30.6%), summed feature 3 (Cω7c and/or Cω6c) (26.0%) and C 3OH (12.1%). The polar lipids were phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phospholipids (PL), glycolipid (GL) and unidentified lipids (UL). Based on the results of the phylogenetic, physiological, biochemical, and morphological analysis, strain SG2303 is recognized as a novel species of the genus Crenobacter, for which the name Crenobacter oryzisoli sp. nov. is proposed. The type strain is SG2303 (= GDMCC 1.3970 = JCM 36468). In addition, SG2303 was also able of phosphorus solubilization and promoting the growth of rice seeds. Strain SG2303 exhibited a relatively high dissolvable phosphorus content of 2.52 µg·mL.
Topics: Soil Microbiology; Phylogeny; RNA, Ribosomal, 16S; DNA, Bacterial; Base Composition; Fatty Acids; China; Phosphates; Nucleic Acid Hybridization; Bacterial Typing Techniques; Phospholipids; Sequence Analysis, DNA; Oryza
PubMed: 38954015
DOI: 10.1007/s00203-024-04070-9 -
Frontiers in Pharmacology 2024Ezetimibe, which lowers cholesterol by blocking the intestinal cholesterol transporter Niemann-Pick C1 like 1, is reported to reduce hepatic steatosis in humans and...
BACKGROUND
Ezetimibe, which lowers cholesterol by blocking the intestinal cholesterol transporter Niemann-Pick C1 like 1, is reported to reduce hepatic steatosis in humans and animals. Here, we demonstrate the changes in hepatic metabolites and lipids and explain the underlying mechanism of ezetimibe in hepatic steatosis.
METHODS
We fed Otsuka Long-Evans Tokushima Fatty (OLETF) rats a high-fat diet (60 kcal % fat) with or vehicle (control) or ezetimibe (10 mg kg) via stomach gavage for 12 weeks and performed comprehensive metabolomic and lipidomic profiling of liver tissue. We used rat liver tissues, HepG2 hepatoma cell lines, and siRNA to explore the underlying mechanism.
RESULTS
In OLETF rats on a high-fat diet, ezetimibe showed improvements in metabolic parameters and reduction in hepatic fat accumulation. The comprehensive metabolomic and lipidomic profiling revealed significant changes in phospholipids, particularly phosphatidylcholines (PC), and alterations in the fatty acyl-chain composition in hepatic PCs. Further analyses involving gene expression and triglyceride assessments in rat liver tissues, HepG2 hepatoma cell lines, and siRNA experiments unveiled that ezetimibe's mechanism involves the upregulation of key phospholipid biosynthesis genes, CTP:phosphocholine cytidylyltransferase alpha and phosphatidylethanolamine N-methyl-transferase, and the phospholipid remodeling gene lysophosphatidylcholine acyltransferase 3.
CONCLUSION
This study demonstrate that ezetimibe improves metabolic parameters and reduces hepatic fat accumulation by influencing the composition and levels of phospholipids, specifically phosphatidylcholines, and by upregulating genes related to phospholipid biosynthesis and remodeling. These findings provide valuable insights into the molecular pathways through which ezetimibe mitigates hepatic fat accumulation, emphasizing the role of phospholipid metabolism.
PubMed: 38953111
DOI: 10.3389/fphar.2024.1406493 -
Lipids in Health and Disease Jun 2024Glycerophospholipids (GPLs) are essential for cell membrane structure and function. Sphingomyelin and its metabolites regulate cell growth, apoptosis, and stress...
BACKGROUND
Glycerophospholipids (GPLs) are essential for cell membrane structure and function. Sphingomyelin and its metabolites regulate cell growth, apoptosis, and stress responses. This study aimed to investigate lipid metabolism in patients experiencing sudden sensorineural hearing loss across all frequencies (AF-SSNHL).
METHODS
The study included 60 patients diagnosed with unilateral AF-SSNHL, among whom 30 patients had a level of hearing improvement ≥ 15 dB after 6 months of follow-up. A propensity score-matched (2:1) control group was used. Liquid chromatography‒mass spectrometry based untargeted lipidomics analysis combined with multivariate statistics was performed to investigate the lipids change. The "lipidome" R package and weighted gene co-expression network analysis (WGCNA) were utilised to assess the lipids' structural features and the association between lipids and hearing.
RESULTS
Lipidomics successfully differentiated the AF-SSNHL group from the control group, identifying 17 risk factors, mainly including phosphatidylcholine (PC), phosphatidylethanolamine (PE), and related metabolites. The ratios of lysophosphatidylcholine/PC, lysophosphatidylethanolamine/PE, and lysodimethylphosphatidylethanolamine/PE were upregulated, while some glycerophospholipid (GPL)-plasmalogens were downregulated in the AF-SSNHL group, indicating abnormal metabolism of GPLs. Trihexosylceramide (d34:1), PE (18:1e_22:5), and sphingomyelin (d40:3) were significantly different between responders and nonresponders, and positively correlated with hearing improvement. Additionally, the results of the WGCNA also suggested that partial GPL-plasmalogens were positively associated with hearing improvement.
CONCLUSION
AF-SSNHL patients exhibited abnormally high blood lipids and pronounced GPLs metabolic abnormalities. Sphingolipids and GPL-plasmalogens had an association with the level of hearing improvement. By understanding the lipid changes, clinicians may be able to predict the prognosis of hearing recovery and personalize treatment approaches.
Topics: Humans; Female; Male; Middle Aged; Biomarkers; Hearing Loss, Sensorineural; Lipid Metabolism; Lipidomics; Adult; Hearing Loss, Sudden; Glycerophospholipids; Aged; Phosphatidylethanolamines; Phosphatidylcholines; Lysophosphatidylcholines; Sphingomyelins; Lysophospholipids
PubMed: 38951804
DOI: 10.1186/s12944-024-02189-8 -
Archives of Microbiology Jun 2024A Gram-stain-negative, aerobic, rod-shaped and motile strain HL-JVS1, was isolated from the gastric tract of a juvenile Pacific white shrimp. Molecular phylogenetic...
A Gram-stain-negative, aerobic, rod-shaped and motile strain HL-JVS1, was isolated from the gastric tract of a juvenile Pacific white shrimp. Molecular phylogenetic analysis based on 16S rRNA gene sequences of strain HL-JVS1 revealed its affiliation with the genus Pleionea, with close relatives including Pleionea mediterranea MOLA115 (97.5%) and Pleionea sediminis S1-5-21 (96.2%). The complete genome of strain HL-JVS1 consisted of a circular 4.4 Mb chromosome and two circular plasmids (6.6 and 35.0 kb) with a G + C content of 43.1%. The average nucleotide identity and digital DNA-DNA hybridization values between strain HL-JVS1 and the type strains of described Pleionea species were 69.7-70.4% and 18.3-18.6%, respectively. Strain HL-JVS1 grew at 10-40 °C (optimum, 30 °C) in the presence of 0.5 - 9.0% (w/v) sea salts (optimum, 2.0 - 2.5%), and at pH range of 5.5 - 10.0 (optimum, pH 6.5). The major fatty acids (> 10%) were summed feature 9 (iso-C ω9c and/or C 10-methyl) (23.3%), iso-C (14.5%), iso-C 3-OH (13.8%) and iso-C (11.0%). The polar lipids were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified aminophospholipid, two unidentified aminolipids, and two unidentified lipids. The respiratory quinone was ubiquinone-8. The comprehensive phylogenetic, phylogenomic, phenotypic and chemotaxonomic results showed that strain HL-JVS1 is distinct from other Pleionea species. Hence, we propose strain HL-JVS1 as a novel species belonging to the genus Pleionea, for which the name Pleionea litopenaei sp. nov. is proposed with HL-JVS1 (= KCCM 90514 = JCM 36490) as the type strain.
Topics: Animals; Penaeidae; Phylogeny; Base Composition; RNA, Ribosomal, 16S; Fatty Acids; DNA, Bacterial; Bacterial Typing Techniques; Nucleic Acid Hybridization; Sequence Analysis, DNA; Genome, Bacterial; Planococcaceae; Gastrointestinal Tract; Phospholipids
PubMed: 38951206
DOI: 10.1007/s00203-024-04064-7 -
Archives of Microbiology Jun 2024A Gram-negative, aerobic, rod-shaped, non-motile bacterium, designated as FTW29, was isolated from surface seawater sampled in Futian district, Shenzhen, China. Growth...
A Gram-negative, aerobic, rod-shaped, non-motile bacterium, designated as FTW29, was isolated from surface seawater sampled in Futian district, Shenzhen, China. Growth of strain FTW29 was observed at 15-42 ℃ (optimum, 28-30 ℃), pH 4.0-9.0 (optimum, pH 5.5-7.5) and in the presence of 0.5-10% NaCl (optimum, 3.0% NaCl). Strain FTW29 showed 95.0-96.8% 16 S rRNA gene sequence similarity to various type strains of the genera Thioclava, Sinirhodobacter, Rhodobacter, Haematobacter and Frigidibacter of the family Paracoccaceae, and its most closely related strains were Thioclava pacifica DSM 10,166 (96.8%) and Thioclava marina 11.10-0-13 (96.7%). The phylogenomic tree constructed on the bac120 gene set showed that strain FTW29 formed a clade with the genus Thioclava, with a bootstrap value of 100%. The evolutionary distance values between FTW29 and type strains of the genus Thioclava were 0.17-0.19, which are below the recommended standard (0.21-0.23) for defining a novel genus in the family Paracoccaceae. In strain FTW29, the major fatty acids identified were summed feature 8 (Cω7c) and C and the predominant respiratory quinones were ubiquinone-10 and ubiquinone-9. The composition of polar lipids in strain FTW29 included diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phospholipid, an unidentified aminolipid, two unidentified glycolipids and an unidentified lipid. The genome of strain FTW29 comprised one circle chromosome and six plasmids, with a G + C content of 61.4%. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values between strain FTW29 and seven type strains of the genus Thioclava were 76.6-78.4%, 53.2-56.4% and 19.3-20.4%, respectively. Altogether, the phenotypic, phylogenetic and chemotaxonomic evidence illustrated in this study suggested that strain FTW29 represents a novel species of the genus Thioclava, with the proposed name Thioclava litoralis sp. nov. The type strain is FTW29 (= KCTC 82,841 = MCCC 1K08523).
Topics: Seawater; Phylogeny; RNA, Ribosomal, 16S; Fatty Acids; DNA, Bacterial; Base Composition; China; Bacterial Typing Techniques; Phospholipids; Alphaproteobacteria; Sequence Analysis, DNA; Ubiquinone; Nucleic Acid Hybridization
PubMed: 38951168
DOI: 10.1007/s00203-024-04057-6