Sodium Houttuyfonate Alleviates Monocrotaline-induced Pulmonary Hypertension by Regulating Orai1 and Orai2.

An increased intracellular Ca2+ concentration ([Ca2+]i) is a key trigger for pulmonary arterial smooth muscle cell (PASMC) proliferation and contributes greatly to pulmonary hypertension (PH). Extracellular Ca2+ influx via a store-operated Ca2+ channel, termed store-operated Ca2+ entry (SOCE), is a crucial mechanism for [Ca2+]i increase in PASMCs. Calcium release-activated calcium modulator (Orai) proteins, consisting of three members (Orai1-3), are the main components of the store-operated Ca2+ channel. Sodium houttuyfonate (SH) is a product of the addition reaction of sodium bisulfite and houttuynin and has antibacterial, antiinflammatory, and other properties. In this study, we assessed the contributions of Orai proteins to monocrotaline (MCT)-enhanced SOCE, [Ca2+]i, and cell proliferation in PASMCs and determined the effect of SH on MCT-PH and the underlying mechanism, focusing on Orai proteins, SOCE, and [Ca2+]i in PASMCs. Our results showed that: 1) Orai1 and Orai2 were selectively upregulated in the distal pulmonary arteries and the PASMCs of MCT-PH rats; 2) knockdown of Orai1 or Orai2 reduced SOCE, [Ca2+]i, and cell proliferation without affecting their expression in PASMCs in MCT-PH rats; 3) SH significantly normalized the characteristic parameters in a dose-dependent manner in the MCT-PH rat model; and 4) SH decreased MCT-enhanced SOCE, [Ca2+]i, and PASMC proliferation via Orai1 or Orai2. These results indicate that SH likely exerts its protective role in MCT-PH by inhibiting the Orai1,2-SOCE-[Ca2+]i signaling pathway.

Novosphingobium album sp. nov., Novosphingobium organovorum sp. nov. and Novosphingobium mangrovi sp. nov. with the organophosphorus pesticides degrading ability isolated from mangrove sediments.

Members of the genus Novosphingobium were frequently isolated from polluted environments and possess great bioremediation potential. Here, three species, designated B2637T, B2580T and B1949T, were isolated from mangrove sediments and might represent novel species in the genus Novosphingobium based on a polyphasic taxonomy study. Phylogenomic analysis revealed that strains B2580T, B1949T and B2637T clustered with Novosphingobium naphthalenivorans NBRC 102051T, 'N. profundi' F72 and N. decolorationis 502str22T, respectively. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between isolates and their closely related species were less than 94 and 54 %, respectively, all below the threshold of species discrimination. The sizes of the genomes of isolates B2580T, B2637T and B1949T ranged from 4.4 to 4.6 Mb, containing 63.3-66.4 % G+C content. Analysis of their genomic sequences identified genes related to pesticide degradation, heavy-metal resistance, nitrogen fixation, antibiotic resistance and sulphur metabolism, revealing the biotechnology potential of these isolates. Except for B2637T, B1949T and B2580T were able to grow in the presence of quinalphos. Results from these polyphasic taxonomic analyses support the affiliation of these strains to three novel species within the genus Novosphingobium, for which we propose the name Novosphingobium album sp. nov. B2580T (=KCTC 72967T=MCCC 1K04555T), Novosphingobium organovorum sp. nov. B1949T (=KCTC 92158T=MCCC 1K03763T) and Novosphingobium mangrovi sp. nov. B2637T (KCTC 72969T=MCCC 1K04460T).

Taxonomy and anticancer potential of Streptomyces niphimycinicus sp. nov. against nasopharyngeal carcinoma cells.

Streptomyces species are ubiquitous, Gram-positive, spore-forming bacteria with the ability to produce various clinically relevant compounds. The strain 4503 T was isolated from mangrove sediments, showing morphological and chemical properties which were consistent with those of members of the genus Streptomyces. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate was primarily identified as members of the genus Streptomyces, sharing more than 99% sequence identity to Streptomyces yatensis DSM 41771 T, S. antimycoticus NBRC 12839 T, and S. melanosporofaciens NBRC 13061 T. Average nucleotide identities (ANI) and digital DNA-DNA hybridization (dDDH) values between strain 4503 T and its close relatives were all below 95-96% and 75% of the novel species threshold, respectively. Results from phylogenetic, genomic, phenotypic, and chemotaxonomic characteristics analyses confirmed that the isolate represented a novel species of the genus Streptomyces, for which the name Streptomyces niphimycinicus sp. nov. 4503 T (= MCCC 1K04557T = JCM 34996 T) is proposed. The bioassay-guided fractionation of the extract of strain 4503 T resulted in the isolation of a known compound niphimycin C, which showed cytotoxic activity against nasopharyngeal carcinoma (NPC) cell lines TW03 and 5-8F with half maximal inhibitory concentration (IC50) values of 12.24 µg/mL and 9.44 µg/mL, respectively. Further experiments revealed that niphimycin C not only exhibited the capacity of anti-proliferation, anti-metastasis, induction of cell cycle arrest, and apoptosis, but was also able to increase the reactive oxygen species (ROS) production and regulate several signaling pathways in NPC cells. KEY POINTS: • Strain 4503 T was classified as a novel species of Streptomyces. • Niphimycin C correlates with the cytotoxic effect of strain 4503 T against NPC cells. • Niphimycin C induces apoptosis, autophagic flux disruption and cell cycle arrest.

Novosphingobium beihaiensis sp. nov., a novel pesticide-tolerant bacterium isolated from mangrove sediments.

A novel Novosphingobium species, designated strain B2638T, was isolated from mangrove sediments which was collected from Beibu Gulf, Beihai, P. R. China. The isolate could grow in the presence of chlorpyrifos. Phylogenetic analysis based on 16S rRNA gene sequence revealed that the isolate belonged to the genus Novosphingobium, showing 99.9% sequence similarity with N. decloroationis 502str22T and less than 98% similarity with other type strain of species of this genus. Molecular typing by BOX-PCR divided strain B2638T and N. declorationis 502str22T into two clusters and indicated that they were not identical. Genomic comparison referenced by values of the DNA-DNA hybridization (dDDH) and the average nucleotide identity (ANI) between strain B2638T and its close phylogenetic neighbors were 20.0-29.5% and 75.3-85.3%, respectively, that were lower than proposed thresholds for bacterial species delineation. The major fatty acids (> 10%) were identified as C18:1 ω7c, C17:1 iso ω9c and C16:0. The main polar lipids contained diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, phosphatidyl glycerol, unidentified lipid and unidentified aminolipid. Results from phenotypic, chemotaxonomic and genotypic analyses proposed that strain B2638T (= MCCC 1K07406T = KCTC 72968 T) is represented a novel species in the genus Novosphingobium, for which the names Novosphingobium beihaiensis sp. nov. is proposed.

Mycolicibacterium aurantiacum sp. nov. and Mycolicibacterium xanthum sp. nov., two novel actinobacteria isolated from mangrove sediments.

Two novel actinobacteria with the ability to degrade kerosene, designated as B3033T and Y57T, were isolated from mangrove sediments in Tieshan Harbour, South China Sea. Both strains are Gram-staining-positive, non-spore forming, slow-growing, oxidase-positive, non-motile and aerobic. Their major cellular fatty acids were C16 : 0 and C18 : 1ω9c. Analysis of 16S rRNA gene sequences revealed the close relationship of strain B3033T to Mycobacterium kyogaense DSM 107316T (99.4 % nucleotide identity) and strain Y57T to Mycolicibacterium chubuense ATCC 27278T (98.7 %) and Mycolicibacterium rufum JS14T (98.7 %). Whole genome average nucleotide blast identity (ANI) and the digital DNA-DNA hybridization (dDDH) values between the two isolates and the type strains of species of the genus Mycolicibacterium were lower than 94 and 45 %, respectively, which were below the threshold values of 95 % (for ANI) and 70 % (for dDDH) recommended for bacterial species differentiation. The genome sequence of B3033T comprised a circular 11.0 Mb chromosome with a DNA G+C content of 68.1 mol%. Y57T had a genome size of 5.6 Mb and a DNA G+C content of 68.7 mol%. Genes involved in degradation of aromatic compounds and copper resistance were identified in the genomes of both strains that could improve their adaptive capacity to the mangrove environment. These results combined with those of chemotaxonomic analyses, MALDI-TOF MS profiles and phenotypic analyses support the affiliation of these strains to two novel species within the genus Mycolicibacterium, for which we propose the names Mycolicibacterium aurantiacum sp. nov. B3033T (=KCTC 49712T=MCCC 1K04526T) and Mycolicibacterium xanthum sp. nov. Y57T (=KCTC 49711T=MCCC 1K04875T) as type strains.

Acuticoccus mangrovi sp. nov., with an antibacterial property, isolated from mangrove sediment.

A Gram-stain-negative, aerobic, milky white bacterium, designated B2012T, was isolated from mangrove sediment collected at Beibu Gulf, South China Sea. Antimicrobial activity assay revealed that the isolate possesses the capability of producing antibacterial compounds. Strain B2012T shared the highest 16S rRNA gene sequence relatedness (96.9-95.5 %) with members of the genus Acuticoccus. The isolate and all known Acuticoccus species contain Q-10 as the main respiratory quinone and have the same polar lipid components (phosphatidylcholine, unidentified glycolipid, unidentified lipid, unidentified amino lipid and phosphatidylglycerol). However, genomic relatedness referred by values of average nucleotide identity, digital DNA-DNA hybridization, average amino acid identity and the percentage of conserved proteins between strain B2012T and other type strains of the genus Acuticoccus were below the proposed thresholds for species discrimination. The genome of strain B2012T was assembled into 65 scaffolds with an N50 size of 244239 bp, resulting in a 5.5 Mb genome size. Eight secondary metabolite biosynthetic gene clusters were detected in this genome, including three non-ribosomal peptide biosynthetic loci encoding yet unknown natural products. Strain B2012T displayed moderately halophilic and alkaliphilic properties, growing optimally at 2-3 % (w/v) NaCl concentration and at pH 8-9. The major cellular fatty acids (>10 %) were anteiso-C15 : 0, C16 : 0 dimethyl aldehyde (DMA) and C16 : 0. Combined data from phenotypic, genotypic and chemotaxonomic analyses suggested that strain B2012T represents a novel species of the genus Acuticoccus, for which the name Acuticoccus mangrovi sp. nov. is proposed. The type strain of the type species is B2012T (=MCCC 1K04418T=KCTC 72962T).

Roseomonas coralli sp. nov., a heavy metal resistant bacterium isolated from coral.

A Gram-stain-negative, aerobic, mesophilic, non-motile bacterium, designated M0104T, was isolated from a gorgonian coral collected from Xieyang island, Guangxi Province, PR China. Colonies of the strain were non-motile cocci and pink. The strain grew at 15-34 °C (optimum, 28 °C), pH 4.5-8.0 (optimum, pH 7.0) and with 0-4% (w/v) NaCl (optimum, 0-2 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain M0104T was closely related to Roseomonas deserti JCM 31275T (96.2 %), Roseomonas vastitatis KCTC 62043T (96.0 %), Roseomonas aerofrigidensis JCM 31878T (95.9 %) and Roseomonas oryzae KCTC 42542T (95.7 %). The strain had an assembly size of 5.0 Mb and a G+C content of 71.0mol%. Genes involved in copper, cadmium, lead, arsenic and zinc resistance were identified in the genome of strain M0104T. The digital DNA-DNA hybridization and average nucleotide identity values between the genome sequence of strain M0104T and those of closely related type strains were 19.4-24.9 % and 74.3-81.8 %, respectively. Strain M0104T contained C18:1 ω7c, C18:3 ω3c, anteiso C11:0 and C16:0 as the major fatty acids (>7 %) and ubiquinone Q-10 as the sole isoprenoid quinone. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine were its major polar lipids. Based on its phenotypic, phylogenetic and chemotaxonomic properties, strain M0104T is proposed to represent a novel species within the genus Roseomonas, for which the name Roseomonas coralli sp. nov. is proposed. The type strain is M0104T (=KCTC 62359T=MCCC 1K03632T).

Mesobaculum littorinae gen. nov., sp. nov., a novel bacterium isolated from a sea snail Littorina scabra.

Members within the family Rhodbacteraceae are morphologically and genetically highly diverse, and originate mostly from coastal marine environments. In this study, a novel species of this family, designated M0103T, was isolated from the surface of a sea snail Littorina scabra. Strain M0103T is Gram-stain-negative, halophilic, non-motile and non-Bacteriochlorophyll a-producing bacterium. Several phenotypic characteristics of the isolate were similar to other species within this family, such as the sole respiratory quinone Q-10 and major fatty acid components C18 : 1 ω7c, C18 : 0 and C16 : 0. Strain M0103T contains a diphosphatidylglycerol, a phosphatidylglycerol, a phosphatidylcholine, a phosphatidy ethanolamine, a phosphatidylinositol, five unidentified phospholipids and four unidentified polar lipids. Based on the 16S rRNA gene sequence analysis, this isolate showed the closest phylogenetic relationship with 'Palleronia pontilimi' GH1-23T (95.1 %). Values of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) of genome sequences were of 70.1-76.4 % and 18.3-20.9 % between the isolate and 24 closely related type strains. Analysis the 4.0 Mb genome of strain M0103T revealed several putative genes associated with cellular stress resistance, which may play protective roles for the isolate in the adaptation to a marine environment. Phylogenetic, phenotypic and chemotaxonomic analyses suggested that strain M0103T represents a novel genus and novel species of the family Rhodobacteraceae, for which the name Mesobaculum littorinae gen. nov., sp. nov. is proposed. The type strain is M0103T (=MCCC 1K03619T=KCTC 62358T).

Thermohalobaculum xanthum gen. nov., sp. nov., a moderately thermophilic bacterium isolated from mangrove sediment.

A novel moderately thermophilic and halophilic bacterium, designated strain M0105T, was isolated from mangrove sediment collected in the Beibu Gulf, south China. The isolate is Gram-negative, non-motile and rod-shaped bacterium with smooth colonies of pale-yellow appearance. Growth occurs at 15-46 °C (optimum 37-40 °C) and pH range of 6.0-10.0 (optimum pH 8.0-9.0). It required 1-7% NaCl (optimum 3-5%) for growth. Strain M0105T was affiliated to the family 'Rhodobacteraceae', sharing the highest 16S rRNA gene sequence similarity with Limibaculum halophilum CAU 1123T (96.8%). The major menaquinone Q-10 and the dominant unsaturated fatty acid (C18:1ω7) in this family were also detected in the strain M0105T. The genome sequence possesses a circular 4.1 Mb chromosome with a G + C content of 67.9%. Strain M0105T encoded many genes for cellular stress resistance and nutrient utilization, which could improve its adaptive capacity to the mangrove environment. Values of conserved proteins (POCP), average nucleotide identity, average amino acid identity (AAI) and DNA-DNA hybridization (dDDH) between the isolate and closely related species were below the proposed threshold for species discrimination. Information from phenotypic, chemotaxonomic and phylogenetic analyses proposed that strain M0105T should be assigned to a novel genus within the family 'Rhodobacteraceae'. Thus, we suggested that the strain M0105T represents a novel species in a new genus, for which the name Thermohalobaculum xanthum gen. nov., sp. nov. is proposed. The type strain of the type species is M0105T (= BGMRC 2019T = KCTC 52118T = MCCC 1K03767T = NBRC 112057T).

Herpetosiphon gulosus sp. nov., a filamentous predatory bacterium isolated from sandy soil and Herpetosiphon giganteus sp. nov., nom. rev.

Three filamentous gliding bacteria from the German Collection of Microorganisms and Cell Cultures, Hp g11, Hp g471 and Hp g472, were subjected to a phylogenetic analysis. These organisms had previously been classified as members of the genus Herpetosiphon based on their growth physiology and morphology. However, a taxonomic assignment at the species level had not been carried out. Analysis of 16S rRNA sequences now confirmed the close relationship of strain Hp g472 to Herpetosiphon aurantiacus DSM 785T (98.6 % nucleotide identity) and Herpetosiphon geysericola DSM 7119T (97.7 %). The results of DNA-DNA hybridization experiments further implied that strain Hp g472 should be classified as a distinct species. The DNA G+C content of strain Hp g472 was 49.9 mol%. The major quinone was MK-10 and the predominant cellular fatty acids were C18 : 1, C16 : 1 and C16 : 0. Based on phenotypic, chemotaxonomic and phylogenetic data it was concluded that strain Hp g472 represents a novel species of the genus Herpetosiphon, for which the name Herpetosiphon gulosus sp. nov. is proposed. The type strain is Hp g472T (=DSM 52871T=NBRC 112829T). In contrast to Hp g472T, the strains Hp g11 and Hp g471 exhibited closest 16S rRNA gene sequence similarity (>99 %) with 'Herpetosiphon giganteus' Hp a2. The distinctive genotypic and phenotypic properties of the latter supported the revival of the name as Herpetosiphon giganteus (ex Reichenbach & Golecki, 1975) sp. nov., nom. rev. We propose the previously deposited reference strain DSM 589T=NBRC 112828T as the type strain.

Herpetopanone, a diterpene from Herpetosiphon aurantiacus discovered by isotope labeling.

The genome of the predatory bacterium Herpetosiphon aurantiacus 114-95T harbors a number of biosynthesis genes, including four terpene cyclase genes. To identify the terpenes biosynthesized from H. aurantiacus 114-95T, we fed the strain with 13C-labeled glucose and, subsequently, searched for characteristic mass shifts in its metabolome. This approach led to the discovery of a new natural product, of which the isotope pattern is indicative for a diterpene originating from the methylerythritol phosphate pathway. After large-scale fermentation of H. aurantiacus 114-95T, the putative diterpene was isolated in sufficient quantity to enable NMR-based structure elucidation. The compound, for which the name herpetopanone is proposed, features a rare octahydro-1H-indenyl skeleton. Herpetopanone bears resemblance to cadinane-type sesquiterpenes from plants, but is structurally entirely unprecedented in bacteria. Based on its molecular architecture, a possible biosynthetic pathway is postulated.

Downregulation of NEBL promotes migration and invasion of clear cell renal cell carcinoma by inducing epithelial-mesenchymal transition.

As a member of the nebulin protein family and a structural protein of cytoskeleton, NEBL plays an important role in cardiac diseases. Recently, literature have reported the involvement of NEBL in the occurrence and development of various cancers except clear cell renal cell carcinoma (ccRCC). In this study, we found that mRNA and protein of NEBL are downregulated remarkably in ccRCC tissues based on both the TCGA database and clinical samples we collected. The areas under curve values of NEBL analyzed based on the TCGA database, qRT-PCR and IHC results were 0.9376, 0.9733 and 0.9807, respectively. The lower mRNA level of NEBL was associated with worse outcomes in ccRCC patients. When overexpressing NEBL in ccRCC cell lines, the proliferation, migration and invasion of ccRCC cells were suppressed significantly, suggesting a tumor suppressor role of NEBL. In addition, we identified that NEBL is closely related to epithelial-mesenchymal transition (EMT), thereby reducing the motility of ccRCC cells. Furthermore, the lower expression of NEBL was correlated with ccRCC patients with distant organ metastasis. In summary, we firstly described the aberrant expression of NEBL and revealed its tumor suppressor role in ccRCC. Our data support that NEBL could serve as a valuable diagnostic and prognostic biomarker in ccRCC, as well as a promising therapeutic target.

HIGD1A inactivated by DNA hypermethylation promotes invasion of kidney renal clear cell carcinoma.

Hypoxia contributes to the tumorigenesis and metastasis of the tumor. However, the detailed mechanisms underlying hypoxia and kidney renal clear cell carcinoma (KIRC) development and progression remain unclear. Here, we investigated the role of the system HIG1 hypoxia inducible domain family member 1 A (HIGD1A) in the proliferation and metastasis of KIRC and elucidated the underlying molecular mechanisms. The expression of HIGD1A is significantly downregulated in KIRC due to promoter hypermethylation. HIGD1A could serve as a valuable diagnostic biomarker in KIRC. In addition, ectopic overexpression of HIGD1A significantly suppressed the growth and invasive capacity of KIRC cells in vitro under normal glucose conditions. Interestingly, the suppressive efficacy in invasion is much more significant when depleted glucose, but not in proliferation. Furthermore, mRNA expression of HIGD1A positively correlates with CDH1 and EPCAM, while negatively correlated with VIM and SPARC, indicating that HIGD1A impedes invasion of KIRC by regulating epithelial-mesenchymal transition (EMT). Our data suggest that HIGD1A is a potential diagnostic biomarker and tumor suppressor in KIRC.

Inactivation of epithelial sodium ion channel molecules serves as effective diagnostic biomarkers in clear cell renal cell carcinoma.

BACKGROUND: Non-voltage-gated sodium channel, also known as the epithelial sodium channel (ENaC), formed by heteromeric complexes consisting of SCNN1A, SCNN1B, and SCNN1G, is responsible for maintaining sodium ion and body fluid homeostasis in epithelial cells. However, no systematic study of SCNN1 family members has been conducted in renal clear cell carcinoma (ccRCC) to date. OBJECTIVE: To investigate the abnormal expression of SCNN1 family in ccRCC and its potential correlation with clinical parameters. METHODS: The transcription and protein expression levels of SCNN1 family members in ccRCC were analyzed based on the TCGA database, and were confirmed by quantitative RT-PCR and immunohistochemical staining assays, respectively. The area under curve (AUC) was used to evaluate the diagnostic value of SCNN1 family members for ccRCC patients. RESULTS: The mRNA and protein expression of SCNN1 family members was significantly downregulated in ccRCC compared with normal kidney tissues, which might be due to DNA hypermethylation in the promoter region. It is worth noting that the AUC of SCNN1A, SCNN1B, and SCNN1G were 0.965, 0.979, and 0.988 based on the TCGA database (p < 0.0001), respectively. The diagnostic value was even higher when combing these three members together (AUC = 0.997, p < 0.0001). Intriguingly, the mRNA level of SCNN1A was significantly lower in females compared with males, while SCNN1B and SCNN1G were increased with the progression of ccRCC and remarkably associated with a worse outcome for patients. CONCLUSION: The aberrantly decrease of SCNN1 family members might serve as valuable biomarkers for the diagnosis of ccRCC.

Loss of ACOX1 in clear cell renal cell carcinoma and its correlation with clinical features.

Clear cell renal cell carcinoma (ccRCC) is a major pathological type of kidney cancer with a poor prognosis due to a lack of biomarkers for early diagnosis and prognosis prediction of ccRCC. In this study, we investigated the aberrant expression of Acyl-coenzyme A oxidase 1 (ACOX1) in ccRCC and evaluated its potential in diagnosis and prognosis. ACOX1 is the first rate-limiting enzyme in the peroxidation ß-oxidation pathway and is involved in the regulation of fatty acid oxidative catabolism. The mRNA and protein levels of ACOX1 were significantly downregulated in ccRCC, and its downregulation was closely associated with the tumor-node-metastasis stage of patients. The ROC curves showed that ACOX1 possesses a high diagnostic value for ccRCC. The OS analysis suggested that lower expression of ACOX1 was closely related to the worse outcome of patients. In addition, gene set enrichment analysis suggested that expression of ACOX1 was positively correlated with CDH1, CDH2, CDKL2, and EPCAM, while negatively correlated with MMP9 and VIM, which strongly indicated that ACOX1 may inhibit the invasion and migration of ccRCC by reversing epithelial-mesenchymal transition. Furthermore, we screened out that miR-16-5p is upregulated at the mRNA transcript level in ccRCC and negatively correlated with ACOX1. In conclusion, our results showed that ACOX1 is abnormally low expressed in ccRCC, suggesting that it could serve as a diagnostic and prognostic biomarker for ccRCC. Overexpression of miR-16-5p may be responsible for the inactivation of ACOX1.

Integration Profiling Between Plasma Lipidomics, Epstein-Barr Virus and Clinical Phenomes in Nasopharyngeal Carcinoma Patients.

Plasma lipidomics has been commonly used for biomarker discovery. Studies in cancer have suggested a significant alteration of circulating metabolite profiles which is correlated with cancer characteristics and treatment outcome. However, the lipidomics characteristics of nasopharyngeal carcinoma (NPC) have rarely been studied. We previously described the phenomenon of lipid droplet accumulation in NPC cells and showed that such accumulation could be regulated by latent infection of Epstein-Barr virus (EBV). Here, we compared the plasma lipidome of NPC patients to that of healthy controls by liquid chromatography-tandem mass spectrometry (LC-MS/MS). We found 19 lipids (e.g., phosphatidylinositols 18:0/20:4 and 18:0/18:2 and free fatty acid 22:6) to be remarkably decreased, whereas 2 lipids (i.e., diacylglycerols 16:0/16:1 and 16:0/20:3) to be increased, in the plasma of NPC patients, compared with controls. Different lipid profiles were also observed between patients with different titers of EBV antibodies (e.g., EA-IgA and VCA-IgA) as well as between patients with and without lymph node or distant organ metastasis. In conclusion, plasma lipidomics might help to differentiate NPC cases from controls, whereas EBV infection might influence the risk and prognosis of NPC through modulating lipid metabolism in both tumor cells and peripheral blood.

UPLC-QTOF-MS metabolomics analysis revealed the contributions of metabolites to the pathogenesis of Rhizoctonia solani strain AG-1-IA.

To explore the pathogenesis of Rhizoctonia solani and its phytotoxin phenylacetic acid (PAA) on maize leaves and sheaths, treated leaf and sheath tissues were analyzed and interpreted by ultra-performance liquid chromatography-mass spectrometry combined with chemometrics. The PAA treatment had similar effects to those of R. solani on maize leaves regarding the metabolism of traumatin, phytosphingosine, vitexin 2'' O-beta-D-glucoside, rutin and DIBOA-glucoside, which were up-regulated, while the synthesis of OPC-8:0 and 12-OPDA, precursors for the synthesis of jasmonic acid, a plant defense signaling molecule, was down-regulated under both treatments. However, there were also discrepancies in the influences exhibited by R. solani and PAA as the metabolic concentration of zeaxanthin diglucoside in the R. solani infected leaf group decreased. Conversely, in the PAA-treated leaf group, the synthesis of zeaxanthin diglucoside was enhanced. Moreover, although the synthesis of 12 metabolites were suppressed in both the R. solani- and PAA-treated leaf tissues, the inhibitory effect of R. solani was stronger than that of PAA. An increased expression of quercitrin and quercetin 3-O-glucoside was observed in maize sheaths treated by R. solani, while their concentrations were not changed significantly in the PAA-treated sheaths. Furthermore, a significant decrease in the concentration of L-Glutamate, which plays important roles in plant resistance to necrotrophic pathogens, only occurred in the R. solani-treated sheath tissues. The differentiated metabolite levels may be the partial reason of why maize sheaths were more susceptible to R. solani than leaves and may explain the underlying mechanisms of R. solani pathogenesis.

Metabolites contributing to Rhizoctonia solani AG-1-IA maturation and sclerotial differentiation revealed by UPLC-QTOF-MS metabolomics.

Rhizoctonia solani is a causative agent of sheath blight, which results in huge economic losses every year. During its life cycle, the formation of sclerotia helps Rhizoctonia solani withstand a variety of unfavorable factors. Oxidative stress is a key factor that induces sclerotium formation. The differentiated and undifferentiated phenotypes of R. solani AG-1-IA were obtained by controlling aerial conditions. Metabolomics based on the mass spectrometry technique combined with multivariate and univariate analyses was used to investigate the metabolic variation in vegetative, differentiated and undifferentiated mycelia. Our results revealed that during maturation, the metabolic levels of N2-acetyl-L-ornithine, 3,1'-(OH)2-Gamma-carotene, (5Z,7E)-(1S,3R)-24,24-difluoro-24a-homo-9,10-seco-5,7,10(19)-cholestatrien-1,3,25-triol, stoloniferone O, PA(O-18:0/12:0), PA(P-16:0/14:0), PA(P-16:0/16:(19Z)) and PA(P-16:0/17:2(9Z,12Z)) were suppressed in both differentiated and undifferentiated mycelia. The concentrations of PE(20:1(11Z)/14:1(9Z)), PE(P-16:0/20:4(5Z,8Z,11Z,13E)(15OH[S])) and PS(12:0/18:1(9Z)) were increased in the differentiated group, while increased levels of N(gamma)-nitro-L-arginine, tenuazonic acid and 9S,10S,11R-trihydroxy-12Z,15Z-octadecadienoic acid were found in the undifferentiated group. Our results suggest that different levels of these metabolites may act as biomarkers for the developmental stages of R. solani AG-1-IA. Moreover, the mechanisms of sclerotium formation and mycelium differentiation were elucidated at the metabolic level.

[Effects of elevated temperature on soil organic carbon and soil respiration under subalpine coniferous forest in western Sichuan Province, China].

To investigate the effects of elevated temperature on the soil organic carbon content, soil respiration rate, and soil enzyme activities in subalpine Picea asperata plantations in western Sichuan Province of China, a simulation study was conducted in situ with open-top chambers from November 2005 to July 2007. The results showed that under elevated temperature, the mean air temperature and soil temperature were 0.42 degrees C and 0.25 degrees C higher than the control, respectively. In the first and the second year, the increased temperature had somewhat decreasing effects on the soil organic carbon and the C/N ratio at the soil depths of 0-10 cm and 10-20 cm. In the first year the soil organic carbon and the C/N ratio in 0-10 cm soil layer decreased by 8.69%, and 8.52%, respectively; but in the second year, the decrements were lesser. Soil respiration rate was significantly enhanced in the first year of warming, but had no significant difference with the control in the second year. In the first year of warming, the activities of soil invertase, polyphenol oxidase, catalase, protease, and urease increased, and the invertase and polyphenol oxidase activities in 0-10 cm soil layer were significantly higher than the control. In the second year of warming, the activities of invertase, protease and urease still had an increase, but those of catalase and polyphenol oxidase had a downtrend, compared with the control.