Evaluation of serum levels of soluble vascular endothelial (sVE)-Cadherin in early- and late-onset preeclampsia serum sVE-Cadherin levels in preeclampsia

OBJECTIVE

Endothelial dysfunction is a major feature of preeclampsia. sVE-cadherin plays a role in the preservation and regulation of the endothelial barrier. For that reason, to evaluation of sVE-cadherin may help elucidate the disease pathophysiology of preeclampsia.

METHODS

The sample size was calculated as a minimum of 46 pregnant women for each group based on serum sVE-Cadherin levels in a pilot study of 10 preeclamptic and 10 control groups. Hundred-twenty pregnancies complicated with early-onset (n = 60) and late-onset (n = 60) preeclampsia were compared with 120 gestational-age (GA)-matched (±1 week) uncomplicated pregnancies. The venous blood sampling was performed upon preeclampsia diagnosis prior to the onset of the labor in the preeclampsia group and the matching (±1 week) pregnancy week in the control group. Demographic and biochemical parameters were evaluated.

RESULTS

Mean serum sVE-Cadherin was significantly higher in women with EOPE compared to that of the GA-matched control group (5.86 ± 1.57 ng/mL vs. 2.28 ± 0.80 ng/mL, p < 0.001), in women with LOPE compared to that of the GA-matched control group (3.11 ± 0.97 ng/mL vs. 1.69 ± 0.87 ng/mL, p < 0.001), and in women with EOPE compared to that of LOPE group (5.86 ± 1.57 ng/mL vs. 3.11 ± 0.97 ng/mL, p < 0.001) after correction for GA. Serum sVE-Cadherin positively correlated with systolic and diastolic blood pressure and a negative correlation with gestational age at sampling.

CONCLUSION

The serum level of sVE-Cadherin was higher in women with preeclampsia than that of GA-matched healthy pregnant women, in women with EOPE compared to that of LOPE. sVE-Cadherin is an important marker in early-onset pre-eclampsia with severe clinical findings.

Interfacial adsorption of soybean phosphatidylethanolamine in different oil phase and the stability of water-in-oil emulsion

Water-in-oil (W/O) emulsion holds great potential in designing fat-reduced foods. However, due to the lack of W/O-type surfactant, formation of all-natural W/O emulsion is challenged. This study aimed to investigate the effect of oil phase on interfacial adsorption of soybean phosphatidylethanolamine (SP) and stability of W/O emulsion. Five oils, including medium chain triglycerides oil (MO), coconut oil (CO), palm kernel oil (PKO), sunflower oil (SO) and rapeseed oil (RO), were selected. Results showed that diffusion rate of SP to the interface ranked as MO > CO > PKO > SO ≈ RO, increasing interfacial adsorption from 50.2 % to 85.3 %. Higher interfacial adsorption improved the deformation resistance of interfacial layer, causing more significant decrease in interfacial tension (3.54 mN/m). So, the largest water fraction (65 %) was stabilized by SP with MO and CO, and exhibited smaller droplet sizes and better stability. Consequently, shorter-chain oil was more suitable for preparing W/O emulsions.

Conventional vs PEGylated loaded liposomal formulations by microfluidics for delivering hydrophilic chemotherapy

Developing drug delivery systems (DDSs) is one of the approaches used to improve cancer treatment, with the main goal of loading cancer drugs into a carrier targeting a specific organ and avoiding the distribution to healthy tissues. Nanoparticles (NPs) have been shown to be one of the optimum carriers that can be used as DDSs. Lipid-based NPs, such as liposomes, have been investigated in the current study due to their low toxicity and ability to carry hydrophilic and hydrophobic molecules. In the current studies, conventional liposomes composed of DPPC, and cholesterol and PEGylated liposomes composed of DPPC, cholesterol, and DSPE-PEG2000 are manufactured and loaded with Carboplatin. The study focused on investigating and comparing the impact of modifying the carboplatin-loaded liposomes with different concentrations of DSPE-PEG2000 on the NP diameter, polydispersity, ζ-potential, encapsulation efficiency (EE%), and drug release. The hydrodynamic microfluidic system was used to investigate any possible improvement in the EE% over other conventional methods. The results showed the microfluidic system's promising effect in enhancing the EE% of the Carboplatin. Moreover, the results showed a smaller diameter and higher stability of the PEGylated liposome. However, conventional liposomes represent better homogeneity and higher encapsulation efficiency for hydrophilic molecules.

Mitochondrial Targeted Thermosensitive Nanocarrier for Near-Infrared-Triggered Precise Synergetic Photothermal Nitric Oxide Chemotherapy

Nitric oxide (NO) intervenes, that is, a potential treatment strategy, and has attracted wide attention in the field of tumor therapy. However, the therapeutic effect of NO is still poor, due to its short half-life and instability. Therapeutic concentration ranges of NO should be delivered to the target tissue sites, cell, and even subcellular organelles and to control NO generation. Mitochondria have been considered a major target in cancer therapy for their essential roles in cancer cell metabolism and apoptosis. In this study, mesoporous silicon-coated gold nanorods encapsulated with a mitochondria targeted and the thermosensitive lipid layer (AuNR@MSN-lipid-DOX) served as the carrier to load NO prodrug (BNN6) to build the near-infrared-triggered synergetic photothermal NO-chemotherapy platform (AuNR@MSN(BNN6)-lipid-DOX). The core of AuNR@MSN exhibited excellent photothermal conversion capability and high loading efficiency in terms of BNN6, reaching a high value of 220 mg/g (w/w), which achieved near-infrared-triggered precise release of NO. The outer biocompatible lipid layer, comprising thermosensitive phospholipid DPPC and mitochondrial-targeted DSPE-PEG2000-DOX, guided the whole nanoparticle to the mitochondria of 4T1 cells observed through confocal microscopy. In the mitochondria, the nanoparticles increased the local temperature over 42 °C under NIR irradiation, and a high NO concentration from BNN6 detected by the NO probe and DSPE-PEG2000-DOX significantly inhibited 4T1 cancer cells in vitro and in vivo under the synergetic photothermal therapy (PTT)-NO therapy-chemotherapy modes. The built NIR-triggered combination therapy nanoplatform can serve as a strategy for multimodal collaboration.

Identification of the role of DAB2 and CXCL8 in uterine spiral artery remodeling in early-onset preeclampsia

Aberrant remodeling of uterine spiral arteries (SPA) is strongly associated with the pathogenesis of early-onset preeclampsia (EOPE). However, the complexities of SPA transformation remain inadequately understood. We conducted a single-cell RNA sequencing analysis of whole placental tissues derived from patients with EOPE and their corresponding controls, identified DAB2 as a key gene of interest and explored the mechanism underlying the communication between Extravillous trophoblast cells (EVTs) and decidual vascular smooth muscle cells (dVSMC) through cell models and a placenta-decidua coculture (PDC) model in vitro. DAB2 enhanced the motility and viability of HTR-8/SVneo cells. After exposure to conditioned medium (CM) from HTR-8/SVneoshNC cells, hVSMCs exhibited a rounded morphology, indicative of dedifferentiation, while CM-HTR-8/SVneoshDAB2 cells displayed a spindle-like morphology. Furthermore, the PDC model demonstrated that CM-HTR-8/SVneoshDAB2 was less conducive to vascular remodeling. Further in-depth mechanistic investigations revealed that C-X-C motif chemokine ligand 8 (CXCL8, also known as IL8) is a pivotal regulator governing the dedifferentiation of dVSMC. DAB2 expression in EVTs is critical for orchestrating the phenotypic transition and motility of dVSMC. These processes may be intricately linked to the CXCL8/PI3K/AKT pathway, underscoring its central role in intricate SPA remodeling.

Lipid nanoparticles containing labile PEG-lipids transfect primary human skin cells more efficiently in the presence of apoE

Nucleic acid-based therapeutics encapsulated into lipid nanoparticles (LNPs) can potentially target the root cause of genetic skin diseases. Although nanoparticles are considered impermeable to skin, research and clinical studies have shown that nanoparticles can penetrate into skin with reduced skin barrier function when administered topically. Studies have shown that epidermal keratinocytes express the low-density lipoprotein receptor (LDLR) that mediates endocytosis of apolipoprotein E (apoE)-associated nanoparticles and that dermal fibroblasts express mannose receptors. Here we prepared LNPs designed to exploit these different endocytic pathways for intracellular mRNA delivery to the two most abundant skin cell types, containing: (i) labile PEG-lipids (DMG-PEG2000) prone to dissociate and facilitate apoE-binding to LNPs, enabling apoE-LDLR mediated uptake in keratinocytes, (ii) non-labile PEG-lipids (DSPE-PEG2000) to impose stealth-like properties to LNPs to enable targeting of distant cells, and (iii) mannose-conjugated PEG-lipids (DSPE-PEG2000-Mannose) to target fibroblasts or potentially immune cells containing mannose receptors. All types of LNPs were prepared by vortex mixing and formed monodisperse (PDI ∼ 0.1) LNP samples with sizes of 130 nm (±25%) and high mRNA encapsulation efficiencies (≥90%). The LNP-mediated transfection potency in keratinocytes and fibroblasts was highest for LNPs containing labile PEG-lipids, with the addition of apoE greatly enhancing transfection via LDLR. Coating LNPs with mannose did not improve transfection, and stealth-like LNPs show limited to no transfection. Taken together, our studies suggest using labile PEG-lipids and co-administration of apoE when exploring LNPs for skin delivery.

Lentzea sokolovensis sp. nov., Lentzea kristufekii sp. nov. and Lentzea miocenica sp. nov., rare actinobacteria from Miocene lacustrine sediment of the Sokolov Coal Basin, Czech Republic

The taxonomic position of three actinobacterial strains, BCCO 10_0061T, BCCO 10_0798T, and BCCO 10_0856T, recovered from bare soil in the Sokolov Coal Basin, Czech Republic, was established using a polyphasic approach. The multilocus sequence analysis based on 100 single-copy genes positioned BCCO 10_0061T in the same cluster as Lentzea waywayandensis, strain BCCO 10_0798T in the same cluster as Lentzea flaviverrucosa, Lentzea californiensis, Lentzea violacea, and Lentzea albidocapillata, and strain BCCO 10_0856T clustered together with Lentzea kentuckyensis and Lentzea alba. Morphological and chemotaxonomic characteristics of these strains support their assignment to the genus Lentzea. In all three strains, MK-9(H4) accounted for more than 80 % of the isoprenoid quinone. The diagnostic diamino acid in the cell-wall peptidoglycan was meso-diaminopimelic acid. The whole-cell sugars were rhamnose, ribose, mannose, glucose, and galactose. The major fatty acids (>10 %) were iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0, and C16 : 0. The polar lipids were diphosphatidylglycerol, methyl-phosphatidylethanolamine, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylglycerol, and phosphatidylinositol. The genomic DNA G+C content of strains (mol%) was 68.8 for BCCO 10_0061T, 69.2 for BCCO 10_0798T, and 68.5 for BCCO 10_0856T. The combination of digital DNA-DNA hybridization results, average nucleotide identity values and phenotypic characteristics of BCCO 10_0061T, BCCO 10_0798T, and BCCO 10_0856T distinguishes them from their closely related strains. Bioinformatic analysis of the genome sequences of the strains revealed several biosynthetic gene clusters (BGCs) with identities >50 % to already known clusters, including BGCs for geosmin, coelichelin, ε-poly-l-lysine, and erythromycin-like BGCs. Most of the identified BGCs showed low similarity to known BGCs (<50 %) suggesting their genetic potential for the biosynthesis of novel secondary metabolites. Based on the above results, each strain represents a novel species of the genus Lentzea, for which we propose the name Lentzea sokolovensis sp. nov. for BCCO 10_0061T (=DSM 116175T), Lentzea kristufekii sp. nov. for BCCO 10_0798T (=DSM 116176T), and Lentzea miocenica sp. nov. for BCCO 10_0856T (=DSM 116177T).

Falsiroseomonas oryziterrae sp. nov., and Falsiroseomonas oryzae sp. nov., isolated from rice paddy soil

Three Gram-stain-negative, aerobic, non-motile and coccobacilli-shaped bacterial strains, designated as NPKOSM-4T, NPKOSM-8 and MO-31T, were isolated from rice paddy soil. They had 96.5-100 % 16S rRNA gene sequence similarity to each other, and strains NPKOSM-4T and NPKOSM-8 showed 100 % 16S rRNA gene sequence similarity, confirming that they were the same species. Comparative analysis of 16S rRNA genes with closely related type strains showed that three isolates were most closely related to Falsiroseomonas terricola EM0302T (96.1-97.8 %), Falsiroseomonas wooponensis WW53T (95.51-96.3 %) and Falsiroseomonas bella CQN31T (96.0-96.5 %), respectively. The genomes of strains NPKOSM-4T and MO-31T consisted of 4 632 875 and 6 455 771 bps, respectively, with 72.0 and 72.1 mol% G+C content. The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between strains NPKOSM-4T and MO-31T and type strains of Falsiroseomonas species were lower than the cut-offs (≥95 % for ANI, ≥95-96 % for AAI and ≥ 70 % for dDDH) required to define a bacterial species. The major fatty acids of strains NPKOSM-4T, NPKOSM-8 and MO-31T were C18 : 1 ω7c and C18 : 1 2-OH (<10 %) and the predominant quinone was Q-10. The polar lipids of strain NPKOSM-4T were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, one unidentified aminophospholipid and three unidentified aminolipids. The polar lipid profiles of strain MO-31T contained diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, one unidentified aminolipid and three unidentified lipids. Based on their distinctive phenotypic, phylogenetic, and chemotaxonomic characteristics, strains NPKOSM-4T, NPKOSM-8 and MO-31T are considered to represent two novel species of the genus Falsiroseomonas, for which the names Falsiroseomonas oryziterrae sp. nov. [to accommodate strains NPKOSM-4T (= KACC 22135T=JCM 34745T), NPKOSM-8 (=KACC 22134=JCM 34746)] and Falsiroseomonas oryzae sp. nov. [to accommodate strain MO-31T (= KACC 22465T=JCM 35532T)] are proposed.

Bioinformatic Analysis Identifies Potential Extracellular Matrix Related Genes in the Pathogenesis of Early Onset Preeclampsia

Early-onset preeclampsia (EOPE) is a complex pregnancy complication that poses significant risks to the health of both mothers and fetuses, and research on its pathogenesis and pathophysiology remains insuffcient. This study aims to explore the role of candidate genes and their potential interaction mechanisms in EOPE through bioinformatics analysis techniques. Two gene expression datasets, GSE44711 and GSE74341, were obtained from the Gene Expression Omnibus (GEO) to identify differentially expressed genes (DEGs) between EOPE and gestational age-matched preterm control samples. Functional enrichment analysis was performed utilizing the kyoto encyclopedia of genes and genomes (KEGG), gene ontology (GO), and gene set enrichment analysis (GSEA). A protein-protein interaction (PPI) network was constructed using the STRING database, and hub DEGs were identified through Cytoscape software and comparative toxicogenomics database (CTD) analysis. Furthermore, a diagnostic logistic model was established using these hub genes, which were confirmed through reverse transcription polymerase chain reaction (RT-PCR). Finally, immune cell infiltration was analyzed using CIBERSORT. In total, 807 DEGs were identified in the GSE44711 dataset (451 upregulated genes and 356 downregulated genes), and 787 DEGs were identified in the GSE74341 dataset (446 upregulated genes and 341 downregulated genes). These DEGs were significantly enriched in various molecular functions such as extracellular matrix structural constituent, receptor-ligand activity binding, cytokine activity, and platelet-derived growth factor. KEGG and GSEA annotation revealed significant enrichment in pathways related to ECM-receptor interaction, PI3K-AKT signaling, and focal adhesion. Ten hub genes were identified through the CytoHubba plugin in Cytoscape. Among these hub genes, three key DEGs (COL1A1, SPP1, and THY1) were selected using CTD analysis and various topological methods in Cytoscape. The diagnostic logistic model based on these three genes exhibited high efficiency in predicting EOPE (AUC = 0.922). RT-PCR analysis confirmed the downregulation of these genes in EOPE, and immune cell infiltration analysis suggested the significant role of M1 and M2 macrophages in EOPE. In conclusion, this study highlights the association of three key genes (COL1A1, SPP1, and THY1) with EOPE and their contribution to high diagnostic efficiency in the logistic model. Additionally, it provides new insights for future research on EOPE and emphasizes the diagnostic value of these identified genes. More research is needed to explore their functional and diagnostic significance in EOPE.

Nanoparticles targeting mutant p53 overcome chemoresistance and tumor recurrence in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) shows high drug resistance and leads to low survival due to the high level of mutated Tumor Protein p53 (TP53). Cisplatin is a first-line treatment option for NSCLC, and the p53 mutation is a major factor in chemoresistance. We demonstrate that cisplatin chemotherapy increases the risk of TP53 mutations, further contributing to cisplatin resistance. Encouragingly, we find that the combination of cisplatin and fluvastatin can alleviate this problem. Therefore, we synthesize Fluplatin, a prodrug consisting of cisplatin and fluvastatin. Then, Fluplatin self-assembles and is further encapsulated with poly-(ethylene glycol)-phosphoethanolamine (PEG-PE), we obtain Fluplatin@PEG-PE nanoparticles (FP NPs). FP NPs can degrade mutant p53 (mutp53) and efficiently trigger endoplasmic reticulum stress (ERS). In this study, we show that FP NPs relieve the inhibition of cisplatin chemotherapy caused by mutp53, exhibiting highly effective tumor suppression and improving the poor NSCLC prognosis.

Effect of Phosphatidylethanolamine on Pore Formation Induced by the Antimicrobial Peptide PGLa

Most antimicrobial peptides (AMPs) induce pore formation and a burst of lipid bilayers and plasma membranes. This causes severe leakage of the internal contents and cell death. The AMP PGLa forms nanopores in giant unilamellar vesicles (GUVs) comprising dioleoylphosphatidylcholine (DOPC) and dioleoylphosphatidylglycerol (DOPG). We here elucidated the effect of the line tension of a prepore rim on PGLa-induced nanopore formation by investigating the interaction of PGLa with single GUVs comprising dioleoylphosphatidylethanolamine (DOPE)/DOPG (6:4) in buffer using the single GUV method. We found that PGLa forms nanopores in the GUV membrane, which evolved into a local burst and burst of GUVs. The rate of pore formation in DOPE/DOPG-GUVs was smaller than that in DOPC/DOPG-GUVs. PGLa is located only in the outer leaflet of a GUV bilayer just before a fluorescent probe AF647 leakage from the inside, indicating that this asymmetric distribution induces nanopore formation. PGLa-induced local burst and burst of GUVs were observed at 10 ms-time resolution. After nanopore formation started, dense particles and small vesicles appeared in the GUVs, followed by a decrease in the GUV diameter. The GUV was finally converted into smaller GUV or lipid membrane aggregates. We discuss the mechanisms of PGLa-induced nanopore formation and its direct evolution to a GUV burst.

Influence of Different Ratios of DSPE-PEG2k on Ester Prodrug Self-Assembly Nanoparticles for Cell Migration and Proliferation Suppression

Background

Bufalin (BFL, an active anti-tumor compound derived from toad venom) is limited in its application due to high toxicity and rapid metabolism of the cardiotonic steroid. Ester prodrug self-assembly nanoparticles have shown significant improved effects in addressing the above-mentioned issues.

Methods

An ester bond was formed between linoleic acid and bufalin to synthesize linoleic acid-bufalin prodrug (LeB). The self-assembly nanoparticles (LeB-PSNs) containing different mass ratios of DSPE-PEG2k and prodrug (6:4, 7:3, 8:2, 9:1 and 10:0) were prepared via co-precipitation method and defined as 6:4-PSNs, 7:3-PSNs, 8:2-PSNs, 9:1-PSNs and LeB-PSNs, respectively. Further, the characterization (particle size, zeta potential, surface morphology and stability) of the nanoparticles was carried out. Finally, we evaluated the impact of different ratios of DSPE-PEG2k on the hydrolysis rate, cytotoxicity, cellular uptake, cell migration and proliferation suppression potential of the prodrug nanoparticles.

Results

The linoleic acid-bufalin prodrug (LeB) was successfully synthesized. Upon the addition of DSPE-PEG2k at different weight ratios, both particle size and polydispersity index (PDI) significantly decreased, while the zeta potential increased remarkably. No significant differences in particle size, PDI and Zeta potential were observed among the 9:1, 8:2 and 7:3 PSNs. Notably, the 8:2 (w/w) DSPE-PEG2k nanoparticles exhibited superior stability, hydrolysis and cellular uptake rates, along with efficient cell cytotoxicity, cell migration and proliferation suppression.

Conclusion

These findings indicate that DSPE-PEG2k could improve the performance of BFL prodrug nanoparticles, namely enhancing stability and achieving adaptive drug release by modulating the hydrolysis rate of esterase. This study therefore provides more opportunities for the development of BFL application.

Gestational testosterone excess early to mid-pregnancy disrupts maternal lipid homeostasis and activates biosynthesis of phosphoinositides and phosphatidylethanolamines in sheep

Gestational hyperandrogenism is a risk factor for adverse maternal and offspring outcomes with effects likely mediated in part via disruptions in maternal lipid homeostasis. Using a translationally relevant sheep model of gestational testosterone (T) excess that manifests maternal hyperinsulinemia, intrauterine growth restriction (IUGR), and adverse offspring cardiometabolic outcomes, we tested if gestational T excess disrupts maternal lipidome. Dimensionality reduction models following shotgun lipidomics of gestational day 127.1 ± 5.3 (term 147 days) plasma revealed clear differences between control and T-treated sheep. Lipid signatures of gestational T-treated sheep included higher phosphoinositides (PI 36:2, 39:4) and lower acylcarnitines (CAR 16:0, 18:0, 18:1), phosphatidylcholines (PC 38:4, 40:5) and fatty acids (linoleic, arachidonic, Oleic). Gestational T excess activated phosphatidylethanolamines (PE) and PI biosynthesis. The reduction in key fatty acids may underlie IUGR and activated PI for the maternal hyperinsulinemia evidenced in this model. Maternal circulatory lipids contributing to adverse cardiometabolic outcomes are modifiable by dietary interventions.

Are Vascular Endothelium and Angiogenesis Effective MicroRNA Biomarkers Associated with the Prediction of Early-Onset Preeclampsia (EOPE) and Adverse Perinatal Outcomes?

MicroRNA is associated with angiogenesis, invasion, proliferation, and vascular endothelial remodeling of various diseases. We aimed to investigate serum MicroRNA (miRNA) levels in preeclampsia (PE) and to determine whether any changes in miRNA levels are useful in predicting early onset preeclampsia (EOPE) and adverse perinatal outcomes. A total of 89 pregnant patients were enrolled in this prospective case-control study (55 PE and 34 healthy controls). miR-17, miR-20a, miR-20b, miR126, miR155, miR-200, miR-222, and miR-210 levels were studied in maternal serum in preeclamptic pregnant women. Multiple logistic regression analyses analyzed the risk factors which are associated with EOPE and adverse maternal outcomes. The Real-time RT-PCR method was used to determine maternal serum miRNA levels. Serum miR-17, miR-20a, miR-20b, miR126, and miR-210 levels were significantly higher in PE than the control group (p < .001, p < .001, p < .001, p < .001 and p = .047 respectively). Increased miR-17, miR-20a, and miR-20b levels were independently associated with PE (OR: 0.642, 95%Cl: 0.486-0.846, p = .002; OR: 0.899, 95%Cl: 0.811-0.996, p = .042 and OR: 0.817, 95%Cl: 0.689-0.970, p = .021). Increased miR-17 and miR-126 levels were negatively correlated with serum EOPE in PE (r = -.313, p = .020), and increased miR-210 levels were significantly positively correlated with EOPE in PE (r = .285, p = .005). Increased expression of serum miR-17, miR-20a, miR-20b, miR126, and miR-210 were found to be associated with PE, also increased expression of miR-17, miR-20a, and miR-20b were to be predicted with PE, also increased maternal serum miR-17 and miR-126 expressions were negatively correlated and increased miR-210 expression was positively correlated with EOPE in PE women.

What's in an E3: role of highly curved membranes in facilitating LC3-phosphatidylethanolamine conjugation during autophagy

During autophagosome formation, ATG3, an E2-like enzyme, catalyzes the transfer of LC3-family proteins (including Atg8 in yeast and LC3- and GABARAP-subfamily members in more complex eukaryotes) from the covalent conjugated ATG3-LC3 intermediate to PE lipids in targeted membranes. A recent study has shown that the catalytically important regions of human ATG3 (hereafter referred to as ATG3), including residues 262 to 277 and 291 to 300, in cooperation with its N-terminal curvature-sensing amphipathic helix (NAH), directly interact with the membrane. These membrane interactions are functionally necessary for in vitro conjugation and in vivo cellular assays. They provide a molecular mechanism for how the membrane curvature-sensitive interaction of the NAH of ATG3 is closely coupled to its conjugase activity. Together, the data are consistent with a model in which the highly curved phagophore rims facilitate the recruitment of the ATG3-LC3 complex and promote the conjugation of LC3 to PE lipids. Mechanistically, the highly curved membranes of the phagophore rims act in much the same manner as classical E3 enzymes in the sumo/ubiquitin system, bringing substrates into proximity and rearranging the catalytic center of ATG3. Future studies will investigate how this multifaceted membrane interaction of ATG3 works with the putative E3 complex, ATG12-ATG5-ATG16L1, to promote LC3-PE conjugation.

Placental progesterone and its receptor in HIV-infected pre-eclamptic women

Given the high prevalence of HIV infection and pre-eclampsia (PE) in South Africa, this study evaluated and compared the placental immunostaining of progesterone (P) and progesterone receptors (PR) in the synergy of HIV-infected PE compared to normotensive pregnant women using immunohistochemistry interfaced with morphometric image analysis. Progesterone immunostaining was expressed widely across exchange and conducting villi within mesenchymal, endothelial, and trophoblast cells. In contrast, PR was expressed within syncytiotrophoblasts and was absent within endothelial cells. In exchange villi, P and PR immuno-expression was significantly lower in PE compared to the normotensive group (p = < 0.0001 and p = < 0.0001, respectively) and within the early-onset pre-eclampsia (EOPE) compared to the late-onset pre-eclampsia (LOPE) group (p = < 0.0001 and p = < 0.0001, respectively). Progesterone immuno-expression was significantly lower in the HIV+ compared to the HIV- group (p = < 0.0001), whilst PR was non-significant. In conducting villi, P and PR immuno-expression was significantly lower in the EOPE compared to the LOPE group (p = < 0.0001 and p = < 0.0001, respectively) and in the HIV+ compared to the HIV- group (p = < 0.0001 and p = 0.0009, respectively). Progesterone immuno-expression was slightly higher in the PE compared to normotensive group, and PR immuno-expression was non-significant. There was a significant difference between P and PR within exchange versus conducting villi regardless of pregnancy type, with villi type accounting for 34.47% and 15.28% of total variance for P and PR, respectively. Placental P and PR immuno-expression is downregulated in the duality of PE and HIV+ infection. The use of combined antiretroviral therapy (cART) may result in defective P synthesis, which causes insufficient binding to its receptors. Consequently, PI3K/AKT, JAK-STAT, and MAPK signalling pathways are affected, impairing trophoblast invasion and leading to pre-eclampsia development. Notably, the decrease in P and PR immuno-expression in EOPE validates their effect on placentation.

Targeted quantitative lipidomic uncovers lipid biomarkers for predicting the presence of compensated cirrhosis and discriminating decompensated cirrhosis from compensated cirrhosis

OBJECTIVES

This study aimed to characterize serum lipid metabolism and identify potential biomarkers for compensated cirrhosis (CC) predicting and decompensated cirrhosis (DC) discrimination using targeted quantitative lipidomics and machine learning approaches.

METHODS

Serum samples from a cohort of 120 participants was analyzed, including 90 cirrhosis patients (45 CC patients and 45 DC patients) and 30 healthy individuals. Lipid metabolic profiling was performed using targeted LC-MS/MS. Two machine learning methods, least absolute shrinkage and selection operator (LASSO), and random forest (RF) were applied to screen for candidate metabolite biomarkers.

RESULTS

The metabolic profiling analysis showed a significant disruption in patients with CC and DC. Compared to the CC group, the DC group exhibited a significant upregulation in the abundance of glycochenodeoxycholic acid (GCDCA), glyco-ursodeoxycholic acid (GUDCA), glycocholic acid (GCA), phosphatidylethanolamine (PE), N-acyl-lyso-phosphatidylethanolamine (LNAPE), and triglycerides (TG), and a significant downregulation in the abundance of ceramides (Cer) and lysophosphatidylcholines (LPC). Machine learning identified 11 lipid metabolites (abbreviated as BMP11) as potential CC biomarkers with excellent prediction performance, with an AUC of 0.944, accuracy of 94.7 %, precision of 95.6 %, and recall of 95.6 %. For DC discrimination, eight lipids (abbreviated as BMP8) were identified, demonstrating strong efficacy, with an AUC of 0.968, accuracy of 92.2 %, precision of 88.0 %, and recall of 97.8 %.

CONCLUSIONS

This study unveiled distinct lipidomic profiles in CC and DC patients and established robust lipid-based models for CC predicting and DC discrimination.

Comparison of immune-related gene signatures and immune infiltration features in early- and late-onset preeclampsia

BACKGROUND

Preeclampsia, a severe pregnancy syndrome, is widely accepted divided into early- and late-onset preeclampsia (EOPE and LOPE) based on the onset time of preeclampsia, with distinct pathophysiological origins. However, the molecular mechanism especially immune-related mechanisms for EOPE and LOPE is currently obscure. In the present study, we focused on placental immune alterations between EOPE and LOPE and search for immune-related biomarkers that could potentially serve as potential therapeutic targets through bioinformatic analysis.

METHODS

The gene expression profiling data was obtained from the Gene Expression Omnibus database. ESTIMATE algorithm and Gene Set Enrichment Analysis were employed to evaluate the immune status. The intersection of differentially expressed genes in GSE74341 series and immune-related genes set screened differentially expressed immune-related genes. Protein-protein interaction network and random forest were used to identify hub genes with a validation by a quantitative real-time PCR. Kyoto Encyclopedia of Genes and Genomes pathways, Gene Ontology and gene set variation analysis were utilized to conduct biological function and pathway enrichment analyses. Single-sample gene set enrichment analysis and CIBERSORTx tools were employed to calculate the immune cell infiltration score. Correlation analyses were evaluated by Pearson correlation analysis. Hub genes-miRNA network was performed by the NetworkAnalyst online tool.

RESULTS

Immune score and stromal score were all lower in EOPE samples. The immune system-related gene set was significantly downregulated in EOPE compared to LOPE samples. Four hub differentially expressed immune-related genes (IL15, GZMB, IL1B and CXCL12) were identified based on a protein-protein interaction network and random forest. Quantitative real-time polymerase chain reaction validated the lower expression levels of four hub genes in EOPE compared to LOPE samples. Immune cell infiltration analysis found that innate and adaptive immune cells were apparent lacking in EOPE samples compared to LOPE samples. Cytokine-cytokine receptor, para-inflammation, major histocompatibility complex class I and T cell co-stimulation pathways were significantly deficient and highly correlated with hub genes. We constructed a hub genes-miRNA regulatory network, revealing the correlation between hub genes and hsa-miR-374a-5p, hsa-miR-203a-3p, hsa-miR-128-3p, hsa-miR-155-3p, hsa-miR-129-2-3p and hsa-miR-7-5p.

CONCLUSIONS

The innate and adaptive immune systems were severely impaired in placentas of EOPE. Four immune-related genes (IL15, GZMB, IL1B and CXCL12) were closely correlated with immune-related pathogenesis of EOPE. The result of our study may provide a new basis for discriminating between EOPE and LOPE and acknowledging the role of the immune landscape in the eventual interference and tailored treatment of EOPE.

DSPE-PEG2000-methotrexate nanoparticles encapsulating phenobarbital sodium kill cancer cells by inducing pyroptosis

Cancer is a life-threatening disease worldwide. Nanomedicine and nanodelivery systems are recently developed scientific field that employs specific materials in the nanoscale range to deliver drugs. Lipid-based nanoparticles are an ideal delivery system since they exhibit many advantages, including high bioavailability, self-assembly, formulation simplicity, and the ability to exhibit a plethora of physicochemical properties. Herein, we report that phenobarbital sodium can kill cancer cells by using the DSPE-PEG2000-methotrexate nanoparticle delivery system, which can target folate receptors that are usually overexpressed on a variety of cancer cells. The released phenobarbital then executes cancer cells by inducing pyroptosis. Results from our animal model further indicate that the nanomedicine of nanoparticle-encapsulated phenobarbital sodium is a promising anticancer therapy.

MicroRNA miR-27a as a possible regulator of anti-inflammatory macrophage phenotype in preeclamptic placenta

INTRODUCTION

The role of the TGFβ signaling pathway, an important cascade responsible for the anti-inflammatory polarization of macrophages, in the development of both early- and late-onset preeclampsia (eoPE and loPE), remains poorly understood. In this study, we examined the components of the TGFβ signaling cascade and macrophage markers within placental tissue in normal pregnancy and in PE.

METHODS

Patients with eoPE, loPE, and normal pregnancy were enrolled in the study (n = 10 in each group). Following techniques were used for the investigation: immunohistochemistry analysis, western blotting, qRT-PCR, isolation of monocytes by magnetic sorting, transfection, microRNA sequencing, and bioinformatic analysis.

RESULTS

We observed a significant decrease in the anti-inflammatory macrophage marker CD206 in the loPE group, alongside with a significant down-regulation of CD206 protein production in both eoPE and loPE groups. The level of CD68-positive cells and relative levels of CD163 and MARCO production were comparable across the groups. However, we identified a significant decrease in the TGFβ receptor 2 production and its gene expression in the PE group. Further analysis revealed a link between TGFBR2 and MRC1 (CD206) genes through a single miRNA, hsa-miR-27a-3p. Transfecting CD14-derived macrophages with the hsa-miR-27a-3p mimic significantly changed TGFBR2 production, indicating the potential role of this miRNA in regulating the TGFβ signaling pathway. We also revealed the up-regulation of hsa-miR-27a-5p and hsa-miR-27a-3p in the trophoblast BeWo b30 cell line under the severe hypoxia condition and the fact that TGFBR2 3' UTR could serve as a potential target for these miRNAs.

DISCUSSION

Our findings uncover a novel potential therapeutic target for managing patients with PE, significantly contributing to a deeper comprehension of the underlying mechanisms involved in the development of this pathology.

Lysobacter changpingensis sp. nov., a novel species of the genus Lysobacter isolated from a rhizosphere soil of strawberry in China

In the present work, we characterized in detail strain CM-3-T8T, which was isolated from the rhizosphere soil of strawberries in Beijing, China, in order to elucidate its taxonomic position. Cells of strain CM-3-T8T were Gram-negative, non-spore-forming, aerobic, short rod. Growth occurred at 25-37 °C, pH 5.0-10.0, and in the presence of 0-8% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CM-3-T8T formed a stable clade with Lysobacter soli DCY21T and Lysobacter panacisoli CJ29T, with the 16S rRNA gene sequence similarities of 98.91% and 98.50%. The average nucleotide identity and digital DNA-DNA hybridization values between strain SG-8 T and the two reference type strains listed above were 76.3%, 79.6%, and 34.3%, 27%, respectively. The DNA G + C content was 68.4% (mol/mol). The major cellular fatty acids were comprised of C15:0 iso (36.15%), C17:0 iso (8.40%), and C11:0 iso 3OH (8.28%). The major quinone system was ubiquinone Q-8. The major polar lipids were phosphatidylethanolamine (PE), phosphatidylethanolamine (PME), diphosphatidylglycerol (DPG), and aminophospholipid (APL). On the basis of phenotypic, genotypic, and phylogenetic evidence, strain CM-3-T8T (= ACCC 61714 T = JCM 34576 T) represents a new species within the genus Lysobacter, for which the name Lysobacter changpingensis sp. nov. is proposed.

Pseudonocardia lacus sp. nov., An Actinomycete Isolated from a Lake Sediment Sample

A novel actinomycete strain, designated H11425T, was isolated from a sediment sample collected from Baihua Lake, Guizhou Province, PR China, and a polyphasic approach was employed to determine its taxonomic position. 16S rRNA gene sequence comparisons showed that strain H11425T is most closely related to Pseudonocardia sulfidoxydans JCM 10411T (97.9%) and Pseudonocardia kunmingensis JCM 32122T (97.8%). Both of phylogenetic analysis based on 16S rRNA gene sequence and phylogenomic analysis based on whole-genome sequence showed that strain H11425T formed a separate clade within the genus Pseudonocardia. The draft genome had a length of 8,059,576 bp with a G + C content of 74.5%. The average nucleotide identity, average amino acid identity, and digital DNA-DNA hybridization values between strain H11425T and its closely related Pseudonocardia species were 76.8-79.0%, 64.8-69.9% and 21.7-23.3%, respectively, which were significantly lower than the widely accepted species-defined threshold. Strain H11425T contained meso-diaminopimelic acid, arabinose, galactose, glucose and ribose in its whole-cell hydrolysates. Mycolic acids were absent. The menaquinone was identifed as MK-8(H4). The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylcholine, an unknown phospholipid and four unidentified aminophospholipids. The major fatty acids were iso-C16:0, iso-C14:0, iso H-C16:1 and iso-C16:0 2OH. On the basis of the taxonomic evidence, strain H11425T represents a novel species of the genus Pseudonocardia, for which the name Pseudonocardia lacus sp. nov. is proposed. The type strain is H11425T (= JCM 34851T = CICC 25118T).

Optimization of PLGA-DSPE hybrid nano-micelles with enhanced hydrophobic capacity for curcumin delivery

Poly (D, L Lactic-co-Glycolic acid) (PLGA) is an FDA-approved polymer. It is distinguished from other biocompatible polymers by its feasibility of production and safety for intravenous cancer tumor targeting. Curcumin (CUR) is a natural molecule with versatile bioactivities including inhibiting the nuclear Factor kappa B (Nf-kB) levels in cancer cells, increased by chemotherapy agents. Our group previously reported a successful decrease in the p65 (RelA) subunit of Nf-kB using 125 µg/ml CUR loaded into PLGA nano-micelles. However, this amount was insufficient to reduce all Nf-kB subunits. This study aimed to increase the hydrophobic capacity of PLGA toward CUR using 1,2-Distearoyl-sn-glycerol-3-phosphoethanolamine (DSPE), an FDA-approved phospholipid. PLGA-DSPE hybrid nano-micelles (HNM) were prepared using two different methods, oil-in-water (OiWa) and film preparation-rehydration (FiRe). The encapsulated CUR was successfully increased to 250 µg/ml using the FiRe method. Physicochemical characterization of CUR-loaded HNM was performed using DLS FT-IR, DSC, and HPLC. In HNM with a size of 156.6 nm, DSPE, incorporated with all functional groups of PLGA, and CUR was trapped in the core of this structure. The release profile of CUR was suitable for targeted cancer therapy and the Encapsulation Efficacy was 92%.

Aspects for development of novel antibacterial medicines using a vitamin D3 decomposition product in Helicobacter pylori infection

A previous study by our group demonstrated that a vitamin D3 decomposition product (VDP1) acts as the selective bactericidal substance on Helicobacter pylori. VDP1 is an indene compound modified with a carbonyl and an alkyl. The alkyl of VDP1 turned out to be a mandatory structure to exert effective bactericidal action on H. pylori. Meanwhile, it still remains to be clarified as to how influence the alteration of the carbonyl in VDP1 has on the anti-H. pylori activity. In this study, we synthesized novel VDP1 derivatives that replaced the carbonyl of VDP1 by various functional groups and investigated the antibacterial action of the VDP1 derivatives on H. pylori. VDP1 derivatives retaining either a hydroxy (VD3-1) or an acetic ester (VD3-3) exhibited more effective bactericidal action to H. pylori than VDP1. The replacement of the carbonyl of VDP1 by either an allyl acetate (VD3-2) or an acrylic acid (VD3-5) provided almost no change to the anti-H. pylori activity. Apart from this, an isomer of VDP1 (VD3-4) slightly improved anti-H. pylori activity of VDP1. Meanwhile, the replacement of the carbonyl of VDP1 by a methyl acrylate (VD3-6) attenuated the anti-H. pylori activity. As with VDP1, its derivatives also were suggested to exert the anti-H. pylori action through the interaction with myristic acid side chains of dimyristoyl-phosphatidylethanolamine, a characteristic membrane lipid constituent of this pathogen. These results indicate that it is capable of developing specific antibacterial medicines for H. pylori targeting the biomembranal dimyristoyl-phosphatidylethanolamine using VDP1 as the fundamental structure.

Saccharopolyspora oryzae sp. nov., isolated from rhizosphere soil of the wild rice species Oryza rufipogon

A novel actinobacterium, designated as strain WRP15-2T, was isolated from rhizosphere soil of rice plant (Oryza rufipogon). The strain was Gram-stain-positive, aerobic, and non-motile. Phylogenetic analysis based on the 16S rRNA gene sequences showed that strain WRP15-2T fell into the genus Saccharopolyspora. The strain shared the highest 16S rRNA gene sequence similarity with the type strains Saccharopolyspora kobensis JCM 9109T (99.1%), Saccharopolyspora indica VRC122T (98.9%), and Saccharopolyspora antimicrobica DSM 45119T (98.7%). However, the digital DNA-DNA hybridization and average nucleotide identity values among these strains confirmed that the microorganism represented a novel member of the genus Saccharopolyspora. Chemotaxonomic data revealed that strain WRP15-2T possessed MK-9(H4) as the predominant menaquinone. It contained meso-diaminopimelic acid as the diagnostic diaminopimelic acid and arabinose, galactose, and ribose as predominant whole-cell sugars. The detected phospholipids were dominated by phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylmethylethanolamine, hydroxy-phosphatidylmethylethanolamine, and phosphatidylcholine. The predominant cellular fatty acids were iso-C16:0, C16:0, and iso-C15:0. The G + C content of the genomic DNA was 69.5%. Based on these genotypic and phenotypic data, it is supported that strain WRP15-2T represents a novel species of the genus Saccharopolyspora, for which the name Saccharopolyspora oryzae sp. nov. is proposed. The type strain is WRP15-2T ( = TBRC 15728T = NBRC 115560T).

Phosphatidylethanolamine and Cholesterol Promote Hemifusion Formation: A Tug of War between Membrane Interfacial Order and Intrinsic Negative Curvature of Lipids

Membrane fusion is an important process for the survival of eukaryotes. The shape of lipids plays an important role in fusion by stabilizing nonlamellar fusion intermediates. Lipids with intrinsic positive curvature such as lysophosphatidylcholine and others inhibit hemifusion formation, whereas lipids having intrinsic negative curvature, e.g., phosphatidylethanolamine and cholesterol (CH), are known to promote hemifusion formation. In this work, we have measured the effect of dioleoylphosphatidylethanolamine (DOPE) and CH on the depth-dependent organization, dynamics, and fusion of dioleoylphosphatidylcholine membranes. Both DOPE and CH promote hemifusion formation despite their ability to order the interfacial and acyl chain region of the membrane and block water percolation at these regions. Generally, membrane ordering and inhibition of water percolation at the acyl chain region are detrimental to membrane fusion. This clearly emphasizes the importance of intrinsic negative curvature of lipids in membrane fusion. Interestingly, DOPE and CH show differential effects on the rate of hemifusion formation, which might be owing to their ability to induce order at the interfacial region and intrinsic negative curvature. Overall, our result is significant in understanding the role of lipidic shape in membrane fusion.

Multifaceted membrane interactions of human Atg3 promote LC3-phosphatidylethanolamine conjugation during autophagy

Autophagosome formation, a crucial step in macroautophagy (autophagy), requires the covalent conjugation of LC3 proteins to the amino headgroup of phosphatidylethanolamine (PE) lipids. Atg3, an E2-like enzyme, catalyzes the transfer of LC3 from LC3-Atg3 to PEs in targeted membranes. Here we show that the catalytically important C-terminal regions of human Atg3 (hAtg3) are conformationally dynamic and directly interact with the membrane, in collaboration with its N-terminal membrane curvature-sensitive helix. The functional relevance of these interactions was confirmed by in vitro conjugation and in vivo cellular assays. Therefore, highly curved phagophoric rims not only serve as a geometric cue for hAtg3 recruitment, but also their interaction with hAtg3 promotes LC3-PE conjugation by targeting its catalytic center to the membrane surface and bringing substrates into proximity. Our studies advance the notion that autophagosome biogenesis is directly guided by the spatial interactions of Atg3 with highly curved phagophoric rims.

Myo-inositol alters the effects of glucose, leptin and insulin on placental palmitic acid and oleic acid metabolism

Well-regulated placental palmitic acid (PA) and oleic acid (OA) metabolism is vital for optimal placental function and fetal development, but dysregulation occurs with gestational diabetes (GDM). We hypothesized that such dysregulation might arise from increased maternofetal glucose, leptin or insulin concentrations present in GDM, and that dysregulated PA and OA lipid metabolism could be moderated by myo-inositol, a natural polyol and potential GDM intervention. Placental explants from 21 women were incubated with stable isotope-labelled 13 C-PA or 13 C-OA for 48 h. Explants were treated with glucose (5, 10 mm) or leptin (13 nm) or insulin (150 nm) in combination with myo-inositol (0.3, 30, 60 μm). Forty-seven 13 C-PA lipids and 37 13 C-OA lipids were measured by liquid chromatography-mass spectrometry (LCMS). Compared with controls (5 mm glucose), glucose (10 mm) increased 19 13 C-OA lipids and nine 13 C-PA lipids, but decreased 13 C-OA phosphatidylethanolamine 38:5 and 13 C-PA phosphatidylethanolamine 36:4. The effects of leptin and insulin were less prominent than glucose, with leptin increasing 13 C-OA acylcarnitine 18:1, and insulin increasing four 13 C-PA triacylglycerides. Most glucose, leptin and insulin-induced alterations in lipids were attenuated by co-incubation with myo-inositol (30 or 60 μm), with attenuation also occurring in all subgroups stratified by GDM status and fetal sex. However, glucose-induced increases in acylcarnitine were not attenuated by myo-inositol and were even exaggerated in some instances. Myo-inositol therefore appears to generally act as a moderator, suppressing the perturbation of lipid metabolic processes by glucose, leptin and insulin in placenta in vitro. Whether myo-inositol protects the fetus and pregnancy from unfavourable outcomes requires further research. KEY POINTS: Incubation of placental explants with additional glucose, or to a lesser extent insulin or leptin, alters the placental production of 13 C-lipids from 13 C-palmitic acid (PA) and 13 C-oleic acid (OA) in vitro compared with untreated controls from the same placenta. Co-incubation with myo-inositol attenuated most alterations induced by glucose, insulin or leptin in 13 C-lipids, but did not affect alterations in 13 C-acylcarnitines. Alterations induced by glucose and leptin in 13 C-PA triacylglycerides and 13 C-PA phospholipids were influenced by fetal sex and gestational diabetes status, but were all still attenuated by myo-inositol co-incubation. Insulin differently affected 13 C-PA triacylglycerides and 13 C-PA phospholipids depending on fetal sex, with alterations also attenuated by myo-inositol co-incubation.

Methyl carbamates of phosphatidylethanolamines and phosphatidylserines reveal bacterial contamination in mitochondrial lipid extracts of mouse embryonic fibroblasts

The occurrence of methyl carbamates of phosphatidylethanolamines and phosphatidylserines in the lipid extract of mitochondria obtained from mouse embryonic fibroblasts was ascertained by hydrophilic interaction liquid chromatography with electrospray ionization single and multi-stage mass spectrometry, performed using sinergically a high resolution (quadrupole-Orbitrap) and a low resolution (linear ion trap) spectrometer. Two possible routes to the synthesis of methyl carbamates of phospholipids were postulated and evaluated: (i) a chemical transformation involving phosgene, occurring as a photooxidation by-product in the chloroform used for lipid extraction, and methanol, also used for the latter; (ii) an enzymatic methoxycarbonylation reaction due to an accidental bacterial contamination, that was unveiled subsequently on the murine mitochondrial sample. A specific lipid extraction performed on a couple of standard phosphatidyl-ethanolamines/-serines, based on purposely photo-oxidized chloroform and deuterated methanol, indicated route (i) as negligible in the specific case, thus highlighting the enzymatic route related to bacterial contamination as the most likely source of methyl carbamates. The unambiguous recognition of the latter might represent the starting point toward a better understanding of their generation in biological systems and a minimization of their occurrence when an artefactual formation is ascertained.

Profile of Human Milk Phospholipids at Different Lactation Stages with UPLC/Q-TOF-MS: Characterization, Distribution, and Differences

Human milk phospholipids are important for the regular growth and development of infants. Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) was employed to qualitatively and quantitatively analyze 277 phospholipid molecular species in 112 human milk samples to obtain a detailed profile of human milk phospholipids along the lactation stage. MS/MS fragmentation patterns of sphingomyelin, phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidylserine were characterized in detail. Phosphatidylcholine is the most dominant group, followed by sphingomyelin. PC(18:0/18:2), SM(d18:1/24:1), PE(18:0/18:0), PS(18:0/20:4), and PI(18:0/18:2) showed the highest average concentration among all of the phosphatidylcholine, sphingomyelin, phosphatidylethanolamine, phosphatidylserine, and phosphatidylinositol molecular species, respectively. The fatty acids attached to the phospholipid molecules were mainly palmitic, stearic, oleic, and linoleic acids, and the plasmalogens decreased along the lactation stage. The increase of sphingomyelins and phosphatidylethanolamines and the decrease of phosphatidylcholines are the key changes from colostrum to transitional milk; the increase of lysophosphatidylcholines and lysophosphatidylethanolamines and the continuous decrease of phosphatidylcholines are the vital changes from transitional milk to mature milk.

Complex electrostatic effects on the selectivity of membrane-permeabilizing cyclic lipopeptides

Cyclic lipopeptides (CLiPs) have many biological functions, including the selective permeabilization of target membranes, and technical and medical applications. We studied the anionic CLiP viscosin from Pseudomonas along with a neutral analog, pseudodesmin A, and the cationic viscosin-E2K to better understand electrostatic effects on target selectivity. Calcein leakage from liposomes of anionic phosphatidylglycerol (PG) and phosphatidylethanolamine (PE) is measured in comparison with net-neutral phosphatidylcholine by time-resolved fluorescence. By contrast to the typical selectivity of cationic peptides against anionic membranes, we find viscosin more active against PG/PE at 30 μM lipid than viscosin-E2K. At very low lipid concentration, the selectivity is reversed. An equi-activity analysis reveals the reciprocal partition coefficients, 1/K, and the CLiP-to-lipid mole ratio within the membrane as leakage after 1 h reaches 50%, Re50. As expected, 1/K to PG/PE is much lower (higher affinity) for viscosin-E2K (3 μM) than viscosin (15 μM). However, the local damage to the PG/PE membrane caused by a viscosin molecule is much stronger than that of viscosin-E2K. This can be explained by the strong membrane expansion due to PG/viscosin repulsion inducing asymmetry stress between the two leaflets and, ultimately, transient limited leakage at Re50 = 0.08. PG/viscosin-E2K attraction opposes expansion and leakage starts only as the PG charges in the outer leaflet are essentially compensated by the cationic peptide (Re50 = 0.32). In the high-lipid regime (at lipid concentrations cL ≫ 1/K), virtually all CLiP is membrane bound anyway and Re50 governs selectivity, favoring viscosin. In the low-lipid regime at cL ≪ 1/K, virtually all CLiP is in solution, 1/K becomes important and the "cation attacks anionic membrane" selectivity gets restored. Overall, activity and selectivity data can only properly be interpreted if the lipid regime is known and predictions for other lipid concentrations or cell counts require knowledge of 1/K and Re50.

Exploring preconception signatures of metabolites in mothers with gestational diabetes mellitus using a non-targeted approach

BACKGROUND

Metabolomic changes during pregnancy have been suggested to underlie the etiology of gestational diabetes mellitus (GDM). However, research on metabolites during preconception is lacking. Therefore, this study aimed to investigate distinctive metabolites during the preconception phase between GDM and non-GDM controls in a nested case-control study in Singapore.

METHODS

Within a Singapore preconception cohort, we included 33 Chinese pregnant women diagnosed with GDM according to the IADPSG criteria between 24 and 28 weeks of gestation. We then matched them with 33 non-GDM Chinese women by age and pre-pregnancy body mass index (ppBMI) within the same cohort. We performed a non-targeted metabolomics approach using fasting serum samples collected within 12 months prior to conception. We used generalized linear mixed model to identify metabolites associated with GDM at preconception after adjusting for maternal age and ppBMI. After annotation and multiple testing, we explored the additional predictive value of novel signatures of preconception metabolites in terms of GDM diagnosis.

RESULTS

A total of 57 metabolites were significantly associated with GDM, and eight phosphatidylethanolamines were annotated using HMDB. After multiple testing corrections and sensitivity analysis, phosphatidylethanolamines 36:4 (mean difference β: 0.07; 95% CI: 0.02, 0.11) and 38:6 (β: 0.06; 0.004, 0.11) remained significantly higher in GDM subjects, compared with non-GDM controls. With all preconception signals of phosphatidylethanolamines in addition to traditional risk factors (e.g., maternal age and ppBMI), the predictive value measured by area under the curve (AUC) increased from 0.620 to 0.843.

CONCLUSIONS

Our data identified distinctive signatures of GDM-associated preconception phosphatidylethanolamines, which is of potential value to understand the etiology of GDM as early as in the preconception phase. Future studies with larger sample sizes among alternative populations are warranted to validate the associations of these signatures of metabolites and their predictive value in GDM.

Restoration of lipid homeostasis between TG and PE by the LXRα-ATGL/EPT1 axis ameliorates hepatosteatosis

Converting lipid disturbances in response to energy oversupply into healthy lipid homeostasis is a promising therapy to alleviate hepatosteatosis. Our clinical studies found that a further elevation of triglyceride (TG) in obese patients with the body mass index (BMI) greater than 28 was accompanied by a further reduction of phosphatidylethanolamine (PE). Shorter survival and poor prognosis were shown for the patients with high TG and low PE levels. Liver X receptor alpha (LXRα) knockout mice aggravated high-fat diet (HFD)-induced obesity and lipid disorders, making the TG enrichment and the PE decrease more pronounced according to the liver lipidomics analysis. The RNA-seq from mice liver exhibited that these metabolism disorders were attributed to the decline of Atgl (encoding the TG metabolism enzyme ATGL) and Ept1 (encoding the PE synthesis enzyme EPT1) expression. Mechanistic studies uncovered that LXRα activated the ATGL and EPT1 gene via direct binding to a LXR response element (LXRE) in the promoter. Moreover, both the supplement of PE in statin or fibrate therapy, and the LXRα inducer (oridonin) ameliorated cellular lipid deposition and lipotoxicity. Altogether, restoration of lipid homeostasis of TG and PE via the LXRα-ATGL/EPT1 axis may be a potential approach for the management of hepatosteatosis and metabolic syndrome.

Potential Role of 68Ga-NOTA-Duramycin PET/CT Imaging for Early Response Evaluation in a Lymphoma Patient: A Case Report

ABSTRACT

Duramycin, a 19 amino acids peptide, is known for its potential to target phosphatidylethanolamine. During cell death (apoptosis), rearrangement of membrane phospholipids results in the externalization of phosphatidylethanolamine to the outer leaflet of the cell membrane, which can be imaged using 68Ga-NOTA-duramycin. We report 68Ga-NOTA-duramycin imaging in a 50-year-old man with biopsy-proven diffuse large B-cell lymphoma planned for anthracycline-based chemotherapy. 68Ga-NOTA-duramycin PET/CT imaging along with 18F-FDG PET/CT was performed before and after 2 cycles of chemotherapy. The tracer avidity in interim 68Ga-NOTA-duramycin PET/CT showed its diagnostic potential to assess early response to chemotherapy.

Paenibacillus hamazuiensis sp. nov., a bacterium isolated from Hamazui hot spring in Yunnan province, south-west China

A bacterial strain, Gram-positive, aerobic, rod-shaped, motile, designated YIM B00624^T which was isolated from a Hamazui hot spring in Tengchong, Yunnan province, south-west China. The strain grew well on International Streptomyces Project (ISP) 2 medium and colonies were creamy yellow, flat and circular. The results of 16S rRNA gene sequence similarity analysis showed that strain YIM B00624^T was closely related to the type strain of Paenibacillus filicis S4^T (95.9%). The main menaquinone of strain YIM B00624^T was menaquinone-7 (MK-7) and major fatty acids were anteiso-C_15:0, anteiso-C_17:0 and C_16:0. The isolate contained meso-diaminopimelic acid as the diagnostic diamino acid and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine and four unidentified glycolipids. The DNA G+C content of strain YIM B00624^T was 53.4 mol%. Based on physiological, phenotypic and chemotaxonomic data, strain YIM B00624^T belongs to a novel species of the genus Paenibacillus, for which the name Paenibacillus hamazuiensis sp. nov. is proposed. The type strain is YIM B00624^T (= CGMCC 1.19245^T = KCTC 43365^T).

Enzymatic Modification of Lecithin for Improved Antioxidant Activity in Combination with Tocopherol in Emulsions and Bulk Oil

Oxidized α-tocopherol can be regenerated by phosphatidylethanolamine (PE), but current commercial sources of PE are too expensive for use as a food additive. The present study aims to determine the optimal reaction conditions for generating high PE lecithin (MHPEL) enzymatically and to validate the MHPEL's synergism with tocopherol in delaying lipid oxidation in an oil-in-water emulsion system at pH 7 and 4 and in bulk oil. Under optimal conditions of pH 9.0, 37 °C and 4 h, a MHPEL with ∼71.6% PE was obtained from 96% phosphatidylcholine lecithin using phospholipase D from Streptomyces chromofuscus. Mixed tocopherols (300 μmol/kg oil) and MHPEL (1500 μmol/kg oil) synergistically increased both the hydroperoxide and hexanal lag phase of lipid oxidation in stripped soybean oil-in-water emulsions at pH 7 by 3 days. At pH 4, this combination increased the hydroperoxide and hexanal lag phases by 3 and 2 days, respectively. The combination of 50 μmol/kg oil α-tocopherol and 1000 μmol/kg oil MHPEL also synergistically increased the hydroperoxide (5 days) and hexanal (4 days) lag phases in stripped bulk soybean oil. This approach represents a potential clean-label antioxidant system that could have commercial applications to decrease food waste.

SELF PRUNING 3C is a flowering repressor that modulates seed germination, root architecture, and drought responses

Allelic variation in the CETS (CENTRORADIALIS, TERMINAL FLOWER 1, SELF PRUNING) gene family controls agronomically important traits in many crops. CETS genes encode phosphatidylethanolamine-binding proteins that have a central role in the timing of flowering as florigenic and anti-florigenic signals. The great expansion of CETS genes in many species suggests that the functions of this family go beyond flowering induction and repression. Here, we characterized the tomato SELF PRUNING 3C (SP3C) gene, and show that besides acting as a flowering repressor it also regulates seed germination and modulates root architecture. We show that loss of SP3C function in CRISPR/Cas9-generated mutant lines increases root length and reduces root side branching relative to the wild type. Higher SP3C expression in transgenic lines promotes the opposite effects in roots, represses seed germination, and also improves tolerance to water stress in seedlings. These discoveries provide new insights into the role of SP paralogs in agronomically relevant traits, and support future exploration of the involvement of CETS genes in abiotic stress responses.

ATP8B1 Deficiency Results in Elevated Mitochondrial Phosphatidylethanolamine Levels and Increased Mitochondrial Oxidative Phosphorylation in Human Hepatoma Cells

ATP8B1 is a phospholipid flippase that is deficient in patients with progressive familial intrahepatic cholestasis type 1 (PFIC1). PFIC1 patients suffer from severe liver disease but also present with dyslipidemia, including low plasma cholesterol, of yet unknown etiology. Here we show that ATP8B1 knockdown in HepG2 cells leads to a strong increase in the mitochondrial oxidative phosphorylation (OXPHOS) without a change in glycolysis. The enhanced OXPHOS coincides with elevated low-density lipoprotein receptor protein and increased mitochondrial fragmentation and phosphatidylethanolamine levels. Furthermore, expression of phosphatidylethanolamine N-methyltransferase, an enzyme that catalyzes the conversion of mitochondrial-derived phosphatidylethanolamine to phosphatidylcholine, was reduced in ATP8B1 knockdown cells. We conclude that ATP8B1 deficiency results in elevated mitochondrial PE levels that stimulate mitochondrial OXPHOS. The increased OXPHOS leads to elevated LDLR levels, which provides a possible explanation for the reduced plasma cholesterol levels in PFIC1 disease.

Sphingomicrobium nitratireducens sp. nov., isolated from a tidal flat in Guangxi

An aerobic, yellow-pigmented and Gram-stain-negative strain, designated as O-35 ^T, was isolated from a tidal flat sediment collected in Dangjiang Town, the southern China. Colonies of strain O-35 ^T were circular with 0.5-1.0 mm in diameter, convex and smooth. Cells of strain O-35 ^T were coccoid-shaped, non-spore forming, non-motile and the strain could reduce nitrate. Growth of strain O-35 ^T was observed at 15-40 °C (optimum 30 °C), at pH 6.0-9.5 (optimum 7.5-8.0) and in 0.5-5.0% NaCl (optimum 2%, w/v). Strain O-35 ^T showed 16S rRNA gene sequence identities of 97.3-97.5% with Sphingomicrobium lutaoense CC-TBT-3 ^T and Sphingomicrobium aestuariivivum AH-M8^T, higher than the rest of Sphingomicrobium type strains. Phylogenetic trees based on the 16S rRNA gene and the core-genome sequences demonstrated that strain O-35 ^T was affiliated within the genus Sphingomicrobium. Overall genome relatedness index calculations revealed that strain O-35 ^T had < 75.8% of average nucleotide identity and < 19.2% of digital DNA-DNA hybridization values with Sphingomicrobium type strains. The sole isoprenoid quinone was ubiquinone-10. The major fatty acids (> 10%) were summed feature 8, summed feature 3, C_16:0 and C_18:1 2-OH. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, sphingoglycolipid, two unidentified glycolipids, one unidentified lipid and one unidentified phospholipid. On the basis of the phenotypic, chemotaxonomic and genomic properties, strain O-35 ^T represents a novel species in the genus Sphingomicrobium, for which the name Sphingomicrobium nitratireducens sp. nov. is proposed. The type strain is O-35 ^T (= KCTC 92308 ^T = MCCC 1K07589^T).

LC–MS Based Lipidomics Depict Phosphatidylethanolamine as Biomarkers of TNBC MDA-MB-231 over nTNBC MCF-7 Cells

Breast cancer (BC) is the first malignant neoplasm in women, with a high death rate despite early diagnoses and treatment advances. Significant differences exist between the most common BC and triple-negative breast cancer (TNBC). TNBC presents molecular differences such as lacking expression of the estrogen receptor (ER), progesterone receptor (PR), and HER2 proteins, making this cancer have a poor clinical prognostic and lack clear strategies for its treatment. However, growing evidence points to metabolic dysregulation as another differential process between stages and types of BC. Therefore, the study of this crucial hallmark could identify new therapeutic targets to treat this aggressive form of BC. These differences induce an in vitro exploration of the metabolic behavior of the MCF7 cells (nTNBC) and MDA-MB-231 (TNBC) cells under lipidomic based LC–MS. The results show more significant differences in lipid regulation (phosphatidylethanolamine) that could be associated with the aggressiveness and difficulties of the treatment of TNBC.

Lipidomics Profiling of Patients with Low Bone Mineral Density (LBMD)

The relationship between lipid metabolism and bone mineral density (BMD) is still not fully elucidated. Despite the presence of investigations using osteoporotic animal models, clinical studies in humans are limited. In this work, untargeted lipidomics profiling using liquid chromatography-mass spectrometry (LC-MS) analysis of human serum samples was performed to identify the lipidomics profile associated with low bone mineral density (LBMD), with a subsequent examination of potential biomarkers related to OP risk prediction or progression. A total of 69 participants were recruited for this cohort study, including the osteoporotic group (OP, n = 25), osteopenia group (ON, n = 22), and control (Ctrl, n = 22). The LBMD group included OP and ON patients. The lipidomics effect of confounding factors such as age, gender, lipid profile, body mass index (BMD), chronic diseases, and medications was excluded from the dataset. The results showed a clear group separation and clustering between LBMD and Ctrl (Q² = 0.944, R² = 0.991), indicating a significant difference in the lipids profile. In addition, 322 putatively identified lipid molecules were dysregulated, with 163 up- and 159 down-regulated in LBMD, compared with the Ctrl. The most significantly dysregulated subclasses were phosphatidylcholines (PC) (n = 81, 25.16% of all dysregulated lipids 322), followed by triacylglycerol (TG) (n = 65, 20.19%), and then phosphatidylethanolamine (PE) (n = 40, 12.42%). In addition, groups of glycerophospholipids, including LPC (7.45%), LPE (5.59%), and PI (2.48%) were also dysregulated as of LBMD. These findings provide insights into the lipidomics alteration involved in bone remodeling and LBMD. and may drive the development of therapeutic targets and nutritional strategies for OP management.

Salinimicrobium sediminilitoris sp. nov., Isolated from a Tidal Flat

A Gram-negative, facultatively anaerobic, motile, and rod-shaped bacterium, designated ASW11-47 ^T, was isolated from a tidal flat sediment taken from the coast of Qingdao, PR China. Phylogenetic analysis of 16S rRNA gene sequence showed that strain ASW11-47 ^T belongs to the genus Salinimicrobium and is most closely related to Salinimicrobium terrae YIM-C338^T (98.68% similarity). The length of draft genome is 3,594,457 bp, and DNA G + C content is 40.8 mol%. The values of average nucleotide identity and digital DNA-DNA hybridization between strain ASW11-47 ^T and closely related strains were in ranges of 75.9-85.9 and 19.7-31.5%, respectively. The major fatty acids (> 10%) were iso-C_15:0 and iso-C_17:0 3-OH. The predominant respiratory quinone was menaquinone-6 and the major polar lipid was phosphatidylethanolamine. On the basis of genotypic, phenotypic, and chemotaxonomic analysis, strain ASW11-47 ^T represents a novel species within the genus Salinimicrobium, for which the name Salinimicrobium sediminilitoris sp. nov. is proposed. The type strain is ASW11-47 ^T (= KCTC 82501 ^T = MCCC 1K05586^T).

Paenibacillus allorhizoplanae sp. nov. from the rhizoplane of a Zea mays root

A Gram-positive staining, aerobic, endospore-forming bacterial strain, isolated from the rhizosphere of Zea mays was studied for its detailed taxonomic allocation. Based on the 16S rRNA gene sequence similarity comparisons, strain JJ-42 ^T was shown to be a member of the genus Paenibacillus, most closely related to the type strain of Paenibacillus pectinilyticus (98.8%). The 16S rRNA gene sequence similarity to all other Paenibacillus species was below 98.5%. The pairwise average nucleotide identity (ANI) and digital DNA−DNA hybridization (dDDH) values of the JJ-42 ^T genome assembly against publicly available Paenibacillus type strain genomes were below 92% and 47%, respectively. The quinone system of strain JJ-42 ^T consisted exclusively of menaquinone MK-7. The polar lipid profile consisted of the major components diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, three aminophospholipids (APL), and one unidentified lipid. The major fatty acids were iso- and anteiso-branched with the major compound anteiso C_15:0. Physiological and biochemical characteristics allowed a further phenotypic differentiation of strain JJ-42 ^T from the most closely related species. Thus, JJ-42 ^T represents a novel species of the genus Paenibacillus, for which the name Paenibacillus allorhizoplanae sp. nov. is proposed, with JJ-42 ^T (= LMG 32089 ^T = CCM 9085 ^T = DSM 111786 ^T = CIP 111891 ^T) as the type strain.

Vibrio ostreae sp. nov., a novel gut bacterium isolated from a Yellow Sea oyster

A Gram-stain-negative, oxidase- and catalase-positive, facultative anaerobic motile bacterium, designated strain OG9-811^T, was isolated from the gut of an oyster collected in the Yellow Sea, Republic of Korea. The strain grew at 10-37 °C, pH 6.0-9.0 and with 0.5-10% (w/v) NaCl. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain OG9-811^T affiliated with the genus Vibrio, with the highest sequence similarity of 98.2% to Vibrio coralliilyticus ATCC BAA-450^T followed by Vibrio variabilis R-40492^T (98.0 %), Vibrio hepatarius LMG 20362^T (97.7 %) and Vibrio neptunius LMG 20536^T (97.6 %); other relatives were Vibrio tritonius JCM 16456^T (97.4 %), Vibrio fluvialis NBRC 103150^T (97.0 %) and Vibrio furnissii CIP 102972^T (97.0 %). The complete genome of strain OG9-811^T comprised two chromosomes of a total 4 807 684 bp and the G+C content was 50.2 %. Results of analysis based on the whole genome sequence showed the distinctiveness of strain OG9-811^T. The average nucleotide identity (ANI) values between strain OG9-811^T and the closest strains V. coralliilyticus ATCC BAA-450^T, V. variabilis R-40492^T, V. hepatarius LMG 20362^T, V. neptunius KCTC 12702^T , V. tritonius JCM 16456^T, V. fluvialis ATCC 33809^T and V. furnissi CIP 102972^T were 73.0, 72.6, 73.3, 73.0, 72.7, 78.5 and 77.8 %, respectively, while the digital DNA-DNA hybridization values between strain OG9-811^T and the above closely related strains were 20.8, 21.2, 20.8, 21.7, 20.7, 23.2 and 22.4 %, respectively. The major fatty acids of strain OG9-811^T were summed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c), summed feature 8 (C_18:1 ω6c and/or C_18:1 ω7c) and C_16:0. The polar lipids contained phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Strain OG9-811^T contained Q-8 as a quinone. On the basis of polyphasic taxonomic characteristics, strain OG9-811^T is considered to represent a novel species, for which the name Vibrio ostreae sp. nov. is proposed. The type strain is OG9-811^T (=KCTC 72623^T=GDMCC 1.2610^T).

Acuticoccus kalidii sp. nov., a 1-aminocyclopropane-1-carboxylate (ACC) deaminase-producing endophyte from a root of Kalidium cuspidatum

A 1-aminocyclopropane-1-carboxylate (ACC) deaminase-producing, Gram-stain-negative, strictly aerobic, non-motile, yellow-reddish, oval-shaped bacterial strain, designated M5D2P5^T, was isolated from a root of Kalidium cuspidatum, in Tumd Right Banner, Inner Mongolia, PR China. M5D2P5^T grew at 10-40 °C (optimum 30-35 °C), pH 5.0-10.0 (optimum pH 8.0) and with 0-7% NaCl (optimum 3.0 %). The strain was positive for catalase and oxidase. The phylogenetic trees based on 16S rRNA gene sequences indicated that M5D2P5^T clustered with Acuticoccus yangtzensis JL1095^T, and shared 98.0, 97.3, 97.2, 96.9 and less than 96.9 % 16S rRNA gene similarities to A. yangtzensis JL1095^T, Acuticoccus mangrovi B2012^T, Acuticoccus sediminis PTG4-2^T, Acuticoccus kandeliae J103^T, and all the other type strains, respectively. However, the phylogenomic tree showed it clustered with A. kandeliae J103^T. M5D2P5^T contained Q-10 as the major respiratory quinone, as well as two minor respiratory quinones, Q-7 and Q-8. Its major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, an unidentified phospholipid, an unidentified glycolipid, and four unidentified lipids. The genomic DNA G+C content was 66.5 %. The digital DNA-DNA hybridization score and the average nucleotide identity based on blast values of M5D2P5^T to A. yangtzensis JL1095^T, A. kandeliae J103^T, A. mangrovi B2012^T, and A. sediminis PTG4-2^T, were 20.8, 23.7, 20.7, and 21.5 %, and 73.3, 79.5, 74.4, and 73.7 %, respectively. The phylogenetic and phenotypic characteristics allowed the discrimination of M5D2P5^T from its phylogenetic relatives. The novel species Acuticoccus kalidii sp. nov. is therefore proposed, and the type strain is M5D2P5^T (=CGMCC 1.19149^T=KCTC 92132^T).

Sphingomonas cannabina sp. nov., isolated from Cannabis sativa L. 'Cheungsam'

A Gram-negative, aerobic, rod-shaped bacterium, designated DM2-R-LB4^T was isolated from Cannabis sativa L. 'Cheungsam' in Andong, Republic of Korea. The strain DM2-R-LB4^T grew at temperatures of 15-45 °C (optimum, 30-37 °C), pH of 5.5-9 (optimum, 8.0), and 0-2 % (w/v) NaCl concentration (optimum, 0%). Phylogenetic analyses based on the 16S rRNA gene sequences revealed that strain DM2-R-LB4^T is related to species of the genus Sphingomonas, and shared 97.8 and 97.5% similarity to Sphingomonas kyenggiensis KCTC 42244^T and Sphingomonas leidyi DSM 4733^T, respectively. The DNA G+C content was 67.9 mol% and genome analysis of the strain DM2-R-LB4^T revealed that the genome size was 4 386 171 bp and contained 4 009 predicted protein-coding genes. The average nucleotide identity (ANI) values between strain DM2-R-LB4^T and S. kyenggiensis KCTC 42244^T, and S. leidyi DSM 4733^T was 76.8 and 76.7 %, respectively, while the values of digital DNA-DNA hybridization (dDDH) were 20.7 and 20.6 %, respectively. C_14 : 0 2-OH, C_16 : 0, and summed feature 8 (C_18 : 1 ω6c and/or C_18 : 1 ω7c) were the major fatty acids (>10 %) in the strain DM2-R-LB4^T. The polar lipids comprised diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidylcholine (PC), sphingoglycolipid (SGL), glycolipid (GL), phospholipid (PL), and two unidentified polar lipids (L1 and L2). Ubiquinone-10 (Q-10) was the only respiratory quinone. The polyamine pattern was found to contain homospermidine, putrescine, and spermidine. The results of phylogenetic anlayses, polyphasic studies, revealed that strain DM2-R-LB4^T represents a novel species of the genus Sphingomonas, for which the name Sphingomonas cannabina sp. nov., is proposed. The type strain is DM2-R-LB4^T (=KCTC 92075^T = GDMCC 1.3018^T).

Streptomyces solincola sp. nov., isolated from soil in Malaysia

A urease-producing Gram-stain-positive actinobacterium, designated strain T5^T, was isolated from a soil sample collected at a highway hillslope in Selangor, Malaysia. The strain was found to produce pale yellowish-pink aerial mycelia with smooth long chain spores and extensively branched light yellowish-pink substrate mycelia on oatmeal agar. Strain T5^T grew at 15-37 °C, pH 6-11, and tolerated up to 9 % (w/v) NaCl, with optimal growth occurring at 28 °C, pH 6-9 and without NaCl. The whole-cell sugar hydrolysate of strain T5^T contained galactose, glucose and ribose. The ll-diaminopimelic acid isomer was detected in the cell wall. Diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol were found to be the predominant polar lipids. The main fatty acids were anteiso-C_17 : 0, iso-C_16 : 0, anteiso-C_15 : 0 and iso-C_14 : 0. Comparative analysis of the 16S rRNA gene sequences indicated that strain T5^T belonged to Streptomyces of the family Streptomycetaceae with the highest 16S rRNA gene sequence similarity to Streptomyces lichenis LCR6-01^T (99.0 %). The overall genome relatedness indices revealed that the closest related species was S. lichenis LCR6-01^T with 89.4 % average nucleotide identity and 33.7 % digital DNA-DNA hybridization. Phylogeny analyses showed that strain T5^T was closely related to Streptomyces fradiae, Streptomyces lavendofoliae, Streptomyces lichenis, Streptomyces roseolilacinus and Streptomyces somaliensis. Based on these polyphasic data, strain T5^T represents a novel species, for which the name Streptomyces solincola sp. nov. is proposed. The type strain is T5^T (=TBRC 5137^T= DSM 42166^T).

Saccharothrix luteola sp. nov., a novel cellulose-degrading actinobacterium isolated from soil and emended description of the genus Saccharothrix

A novel cellulose-degrading actinobacterium, designated strain NEAU-S10^T, was isolated from soil collected from Chifeng, Inner Mongolia Autonomous Region, PR China, and characterized using a polyphasic approach. Pairwise similarity of the 16S rRNA gene sequence showed that strain NEAU-S10^T was a representative of Saccharothrix and was closely related to Saccharothrix carnea NEAU-yn17^T (99.2 %), Saccharothrix saharensis SA152^T (99.0 %), Saccharothrix texasensis DSM 44231^T (98.5 %) and Saccharothrix xinjiangensis NBRC 101911^T (98.5 %). Physiological and chemotaxonomic characteristics of the strain further supported its affiliation to the genus Saccharothrix. The whole-cell sugars contained galactose, ribose and mannose. The polar lipids contained diphosphatidylglycerol, phosphatidylmonomethylethanolamine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannoside. The predominant menaquinones were MK-9(H₀), MK-9(H₂), MK-9(H₄) and MK-10(H₄). The major fatty acids were iso-C_16 : 0, C_16 : 0, anteiso-C_17 : 0, iso-C_15 : 0 and iso-C_17 : 0. The genomic DNA G+C content was 71.8 mol%. The levels of digital DNA-DNA hybridization between isolate and S. carnea NEAU-yn17^T, S. saharensis SA152^T and S. texasensis DSM 44231^T were 40.1 % (37.6-42.6 %), 38.soap8 % (36.3-41.3 %) and 44.8 % (42.2-47.3 %) and the ANI values between them were determined to be 90.2, 89.8 and 91.7 %, the results indicated that strain NEAU-S10^T could be distinguished from its reference strains. The assembled genome sequence of strain NEAU-S10^T was found to be 10 305 394 bp long. The NCBI Prokaryotic Genome Annotation Pipeline (PGAP) revealed 8 994 protein-coding genes. Genomic analysis and Congo red staining test indicated that strain NEAU-S10^T had the potential to degrade cellulose. The genomic and phenotypic results indicate that strain NEAU-S10^T represents a novel species of the genus Saccharothrix, for which the name Saccharothrix luteola sp. nov. is proposed, with NEAU-S10^T (=CCTCC AA 2020037^T=JCM 34800^T) as the type strain.

Luteolibacter marinus sp. nov., a novel bacterium in the family Verrucomicrobiaceae, isolated from marine sediment

A Gram-negative, rod-shaped, non-motile and strictly aerobic bacterium, designated NBU1238^T, was isolated from marine sediment sampled on Meishan Island located in the East China Sea. Strain NBU1238^T was able to grow optimally at 28-32 °C, at pH 7.5 and with no NaCl. Catalase and oxidase activities, H₂S production and hydrolysis of Tweens 40 and 60 were positive. Methyl red reaction, Voges-Proskauer test and hydrolysis of starch, casein and Tweens 20 and 80 were negative. The major cellular fatty acids were iso-C_14 : 0, C_16 : 0, C_16 : 1  ω9c and C_14 : 0. The only respiratory quinone was menaquinone-9. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylmethylethanolamine. The 16S rRNA gene sequence of strain NBU1238^T showed 95.6, 95.6, 94.8 and 93.8% sequence similarity to Luteolibacter flavescens GKX^T, Luteolibacter luteus G-1-1-1^T, Luteolibacter arcticus MC 3726^T and Luteolibacter pohnpeiensis A4T-83^T, respectively. Phylogenetic analyses indicated that strain NBU1238^T clustered with the genus Luteolibacter and was closely related to strains L. flavescens GKX^T, L. arcticus MC 3726^T and L. luteus G-1-1-1^T. The average nucleotide identity and digital DNA-DNA hybridization values between strain NBU1238^T and related species of genus Luteolibacter were well below the threshold limit for prokaryotic species delineation. The DNA G+C content of the genomic DNA was 65.0 mol%. Based on its phenotypic, chemotaxonomic and genotypic data, strain NBU1238^T is considered to be a representative of a novel species in the genus Luteolibacter, for which the name Luteolibacter marinus sp. nov. is proposed. The type strain is NBU1238^T (=KCTC 82227^T=MCCC 1K04772^T).

Hephaestia mangrovi sp. nov., a novel endophytic bacterium isolated from Aegiceras corniculatum

A Gram-stain-negative, aerobic, motile, rod-shaped bacterium, designated CMS5P-6^T, was isolated from a surface-sterilized bark of Aegiceras corniculatum collected from Guangxi Zhuang Autonomous Region, PR China, and investigated by a polyphasic approach to determine its taxonomic position. Strain CMS5P-6^T was found to grow optimally with 0-1 % (w/v) NaCl, at 30 °C and pH 6.0-7.0. Substrate mycelia and aerial mycelia were not formed, and no diffusible pigments were observed on the media tested. Phylogenetic analysis showed that strain CMS5P-6^T showed high 16S rRNA gene sequence similarity of 96.7 % to Hephaestia caeni DSM 25527^T and Sphingomonas colocasiea CC-MHH0539^T. The average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values between strain CMS5P-6^T and H. caeni DSM 25527^T were 78.0, 21.7 and 70.8 %, respectively. The average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values between strain CMS5P-6^T and S. colocasiea JCM 31229^T were 74.0, 19.9 and 61.4 %, respectively. Phylogenomic analyses based on genome sequences showed that strain CMS5P-6^T and H. caeni DSM 25527^T formed a distinct cluster within the family Sphingomonadaceae and far away from S. colocasiea JCM 31229^T. The DNA G+C content of strain CMS5P-6^T was determined to be 65.6 mol%. The cell-wall peptidoglycan was found to contain meso-diaminopimelic acid as the diagnostic diamino acid and ubiquinone Q-10 was identified as the respiratory lipoquinone. The polar lipids were found to comprise diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, sphingoglycolipid and two unidentified aminolipids, and the major fatty acids were identified as C_18 : 1  ω7c, C_19 : 0 cycloω8c and C_16 : 0. On the basis of phylogenetic, genomic, chemotaxonomic and phenotypic data, strain CMS5P-6^T can be concluded to represent a novel species of the genus Hephaestia, for which the name Hephaestia mangrovi sp. nov. is proposed. The type strain is CMS5P-6^T (=JCM 33125^T=CGMCC 1.13868^T).