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1.
Ying Yong Sheng Tai Xue Bao ; 35(3): 705-712, 2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38646758

ABSTRACT

The composition and stability of soil aggregates are important indicators for measuring soil quality, which would be affected by land use changes. Taking wetlands with different returning years (2 and 15 years) in the Yellow River Delta as the research object, paddy fields and natural wetlands as control, we analyzed the changes in soil physicochemical properties and soil aggregate composition. The results showed that soil water content, total organic carbon, dissolved organic carbon and total phosphorus of the returning soil (0-40 cm) showed an overall increasing trend with returning period, while soil pH and bulk density was in adverse. There was no significant change in clay content, electrical conductivity, and total nitrogen content. The contents of macro-aggregates and micro-aggregates showed overall increasing and decreasing trend with returning period, respectively. The stability of aggregates in the topsoil (0-10 cm) increased with returning years. Geometric mean diameter and mean weight diameter increased by 8.9% and 40.4% in the 15th year of returning, respectively, while the mass proportion of >2.5 mm fraction decreased by 10.5%. There was no effect of returning on aggregates in subsoil (10-40 cm). Our results indicated that returning paddy field to wetland in the Yellow River Delta would play a positive role in improving soil structure and aggregate stability.


Subject(s)
Oryza , Rivers , Soil , Wetlands , Soil/chemistry , China , Rivers/chemistry , Oryza/growth & development , Oryza/chemistry , Environmental Monitoring , Agriculture/methods , Phosphorus/analysis , Phosphorus/chemistry , Carbon/analysis , Carbon/chemistry
2.
Ying Yong Sheng Tai Xue Bao ; 34(11): 2985-2992, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37997409

ABSTRACT

The temperature sensitivity of soil carbon mineralization (Q10) is an important index to evaluate the responses of ecosystem carbon cycling to climate change. We examined the effects of three electron acceptors [SO42-, NO3- and Fe(Ⅲ)] addition on the Q10 value of anaerobic carbon mineralization of Phragmites australis community soil (0-10 cm) in the Yellow River Estuary wetland with the closed culture-gas chromatography method. The results showed that the three electron acceptors addition inhibited the production of CO2 and CH4 during the 48-day culture period, with a decrease of 17.3%-20.8% for CO2 and 29.2%-36.2% for CH4. Generally, the CO2 production differed with the concentrations of electron acceptors, while CH4 production differed with the type of electron acceptors. The CO2:CH4 ratios were significantly different with temperature, indicating an obvious temperature dependence for the anaerobic carbon mineralization pathway. The Q10 values of CO2 and CH4 production under three electron acceptor additions ranged from 1.08 to 1.11 and from 1.19 to 1.37, respectively, showing an increasing trend compared with the control. The type and concentration of electron acceptors affected the temperature dependence of CO2 production, while electron acceptors affected that of CH4 production. It is suggested that the input of reducing salts would retard the mineralization loss of organic carbon in estuary freshwater wetlands under the background of climate change, but enhance the sensitivity of carbon mineralization to increasing temperature.


Subject(s)
Soil , Wetlands , Soil/chemistry , Rivers , Ecosystem , Carbon Dioxide/analysis , Carbon/analysis , Estuaries , Temperature , Anaerobiosis , Electrons , Ferric Compounds , China , Methane/analysis
3.
Huan Jing Ke Xue ; 44(8): 4698-4705, 2023 Aug 08.
Article in Chinese | MEDLINE | ID: mdl-37694662

ABSTRACT

Carbon (C), nitrogen (N), and phosphorus (P) are important nutrients, and their ecological stoichiometric characteristics can reflect the quality and fertility capacity of soil, which is critical to understanding the stable mechanisms of estuarine wetland ecosystems. Under global changes, the increase in salinity and flooding caused by sea level rise will lead to changes in biogeochemical processes in estuarine wetlands, which is expected to affect the ecological stoichiometric characteristics of soil C, N, and P and ultimately interfere with the stability of wetland ecosystems. However, it remains unclear how the C, N, and P ecological stoichiometric characteristics respond to the water-salt environment in estuarine wetlands. We differentiated changes in the C, N, and P ecological stoichiometric characteristics through an ex-situ culture experiment for 23 months in the Yellow River Estuary Wetland. The five sites with distinct tidal hydrology were selected to manipulate translocation of soil cores from the freshwater marsh to high-, middle-, and low-tidal flats in June 2019. The results showed that soil water content (SWC); electrical conductivity (EC); and C, N, and P ecological stoichiometric characteristics of freshwater marsh soil significantly changed after translocation for 23 months. SWC decreased on the high- and middle-tidal flats (P<0.05) and increased on the low-tidal flat (P<0.05). EC increased to different degrees on all three tidal flats (P<0.05). Soil total organic carbon (TOC) and total nitrogen (TN) were significantly lower on the high-tidal flat (P<0.05), whereas total phosphorus (TP) was significantly lower on the middle- and high-tidal flats (P<0.05). C:N was decreased on the high- and middle-tidal flats (P<0.05); C:P and N:P were lower on the high-tidal flat; and all C, N, and P ecological stoichiometric characteristics showed no change on the low-tidal flat (P>0.05). Pearson's analysis showed that the ecological stoichiometric characteristics of C, N, and P were related to some properties of soil over the culture sites. The PLS-SEM model showed that the water-salt environment had different effects on soil C:N, C:P, and N:P through the main pathways of negative effects on soil TOC and TP. The results suggest that sea level rise may impact the C, N, and P ecological stoichiometric characteristics in freshwater marsh soil, resulting in some possible changes in the nutrient cycles of estuarine wetlands.

4.
J Am Chem Soc ; 145(18): 9982-9987, 2023 May 10.
Article in English | MEDLINE | ID: mdl-37126789

ABSTRACT

Although the synthesis of low-dimensional metal sulfides by assembling cluster-based units is expected to promote the development of optical materials and models of enzyme active centers such as dinitrogenase, it is faced with limited assembly methodology. Herein we present a cut-to-link strategy to generate high-nuclearity assemblies, inspired by the formation of a Z-type dimer of the W-S-Cu analogues of PN cluster through in situ release of active linkers. Four new compounds with structures based on the same {Tp*WS3Cu3} incomplete cubane-like units were obtained using varied combinations of mild reagents. Open-aperture Z-scan measurements demonstrated the highest-nuclearity complex has the largest nonlinear optical absorption coefficient among discrete cluster-based materials reported to date. This approach enables building high-nuclearity metal sulfide clusters through cluster-based building blocks and opens a way to the design and exploration of materials based on well-identified building blocks.

5.
Huan Jing Ke Xue ; 43(7): 3552-3561, 2022 Jul 08.
Article in Chinese | MEDLINE | ID: mdl-35791539

ABSTRACT

In order to explore dissolved organic matter (DOM) components and their origins in metropolitan lakes and reservoirs in the karst region, the typical Hongfeng Lake, Baihua Lake, Songbaishan Reservoir, and Aha Reservoir were investigated in Guiyang City. Surface water parameters, including dissolved organic carbon (DOC), chlorophyll a (Chla), and optical parameters (a254, a280, a350, E2:E3, S275-295, FI, ß:α, BIX, and HIX) were analyzed. Fluorescence peaks (B, T, A, M, C, D, and N) and three-dimensional matrix fluorescence with parallel factor analysis (EEM-PARAFAC) were employed to explain distinct DOM abundances and proportions. Meanwhile, Spearman's correlation coefficients and principal component analysis (PCA) were used to decipher parameter types and primary environmental processes. The results showed that aquatic ρ(DOC) and ρ(Chla) ranged between 4.24-11.9 mg·L-1 and 0.32-19.7 µg·L-1, respectively. High humic-like (a254) and protein DOM (a280) were observed in the Songbaishan Reservoir, resulting in higher DOM molecular weight when compared to that in other lakes and reservoirs. Surface water DOM mainly contained visible-light humic-like (23.8%-46.9%) and terrestrial fulvic-like components (17.6%-28.4%). High FI, ß:α, and BIX but low HIX values in this study suggested that endogenous inputs largely contributed to aquatic DOM. Aquatic DOM component and source characteristics were significantly correlated with each other. Furthermore, inputs of humic-like DOM and microbial metabolism, as well as coupled carbonate dissolution and photosynthesis, drove dynamic DOM behaviors in the karst lakes and reservoirs.


Subject(s)
Dissolved Organic Matter , Lakes , China , Chlorophyll A , Water
6.
Dalton Trans ; 51(16): 6358-6365, 2022 Apr 20.
Article in English | MEDLINE | ID: mdl-35383821

ABSTRACT

Reactions of [Et4N][Tp*WS3(CuCl)3] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with 2 equiv. of AgOTf (OTf- = trifluoromethanesulfonate) and 1 equiv. of several bidentate pyridine ligands including 2,5-bis(pyridine-4-yl)thiazolo[5,4-d]thiazole (L1), 2,7-di(pyridin-4-yl)-9H-fluorene (L2), 2,7-di(pyridin-4-yl)-9H-carbazole (L3), and 2,7-di(pyridin-4-yl)-9H-fluoren-9-one (L4) afforded four W/Cu/S cluster-based supramolecular compounds [(Tp*WS3Cu2Cl)2(L1)] (2), {[(Tp*WS3Cu3)2(µ-Cl)2(µ4-Cl)]2(L2)2}(OTf)2 (3), {[(Tp*WS3Cu3)2(µ-Cl)2(µ4-Cl)]2(L3)2}(OTf)2 (4) and {[(Tp*WS3Cu3)2(µ-Cl)2(µ4-Cl)]2(L4)2}(OTf)2 (5). Compounds 2-5 were characterized by elemental analysis, IR, UV-vis, 1H NMR, and single-crystal X-ray diffraction analysis. The neutral cluster 2 behaves as a supramolecular wire constructed by L1 bridging two butterfly-shaped [Tp*WS3Cu2Cl] cores. The cluster cations of 3-5 contain two [(Tp*WS3Cu3)2(µ-Cl)2(µ4-Cl)]+ cores linked by two L2, L3, or L4 ligands, which finally formed a cationic supramolecular rectangle. The third-order nonlinear-optical (NLO) properties of 3-5 in DMF were also investigated by Z-scan techniques and their NLO responses were enhanced compared to those of their precursor 1.

7.
Sci Rep ; 11(1): 5002, 2021 03 02.
Article in English | MEDLINE | ID: mdl-33654125

ABSTRACT

Soil labile organic carbon (LOC) responds rapidly to environmental changes and plays an important role in carbon cycle. In this study, the seasonal fluctuations in LOC, the activities of carbon-cycle related enzymes, and the bacterial and fungal communities were analyzed for soils collected from two forests, namely Betula albosinensis (Ba) and Picea asperata Mast. (Pa), in the Qinling Mountains of China. Results revealed that the seasonal average contents of microbial biomass carbon (MBC), easily oxidized organic carbon (EOC), and dissolved organic carbon (DOC) of Pa forest soil were 13.5%, 30.0% and 15.7% less than those in Ba soil. The seasonal average enzyme activities of ß-1,4-glucosidase (ßG), and ß-1,4-xylosidase (ßX) of Ba forest soils were 30.0% and 32.3% higher than those of Pa soil while the enzyme activity of cellobiohydrolase (CBH) was 19.7% lower. Furthermore, the relative abundance of Acidobacteria was significantly higher in summer than in winter, whereas the relative abundance of Bacteroidetes was higher in winter. Regarding the fungal communities, the relative abundance of Basidiomycota was lowest in winter, whereas Ascomycota predominated in the same season. In addition, the soil LOC was significantly positively correlated with the CBH, ßG and ßX activities. Changes in LOC were significantly correlated with Acidobacteria, Bacteroidetes and Basidiomycota. We conclude that the seasonal fluctuations in forest soil LOC fractions relied on carbon cycle-associated enzymatic activities and microorganisms, which in turn were affected by climatic conditions.

8.
Ying Yong Sheng Tai Xue Bao ; 31(10): 3413-3423, 2020 Oct.
Article in Chinese | MEDLINE | ID: mdl-33314831

ABSTRACT

Understanding the dynamics of phosphate-solubilizing and N2-fixing bacteria on soil nutrient and related enzyme activity under different organic fertilizer proportions (OFP) could provide references for screening appropriate inoculant type, OFP, and fertilization period. Here, we set four OFP levels (mass ratio: 0%, 4%, 8%, 12%) and inoculated two phosphate-solubilizing bacteria (Bacillus megaterium, Pseudomonas fluorescens) and two N2-fixing bacteria (Azotobacter chroococcum, Azospirillum brasilence) in the subtropical yellow-brown barren soil. After a 60-day soil incubation under controlled conditions (28 ℃, darkness), we examined the impacts of single/mixed applications of beneficial bacteria on soil available nutrients and related enzyme activities at different OFP levels and different sampling times (3rd, 8th, 16th, 30th, 45th, 60th day). The results showed that soil available nutrient contents increased with the elevated OFP levels, and exhibited as 12%>8%>4%>0%. With the extension of culture time, soil nutrient contents in all treatments first increased and then decreased. Compared with the single application of organic fertilizer, combined application of organic fertilizer and bacterial inoculants resulted in higher and longer improvement of soil nutrient contents and enzyme activities. The effects of inoculants on soil nutrient properties varied across four OFP levels. When the OFP was low (0-4%), inoculation significantly increased soil available nutrient contents, with no the differences between inoculants at the initial stage. However, with the extension of the culture time and the elevation of OFP, phosphate-solubilizing bacteria (especially for B. megaterium) significantly increased available phosphorus content while N2-fixing bacteria (especially for A. brasilence) significantly increased available nitrogen content. The mixed inoculant with four strains showed phosphate-solubilizing effect on soil and performed better than the single application of phosphate-solubilizing bacteria, but without prominent effect on nitrogen fixation. Soil nutrient contents were positively correlated with enzyme activity, which was affected by both cultural time and carbon-nitrogen ratio. Bacterial inoculations could significantly increase nutrient contents in the short term, but the specific functions of beneficial bacteria on soil were highly dependent on organic carbon input and carbon-nitrogen ratio. Coupled application of inoculants and organic fertilizer at an appropriate OFP level (8%-12%) could increase and extend the soil-remediating effects, while the inoculation should be conducted with an interval of 45-60 days to ensure the survival rate and the consecutive effect on soil.


Subject(s)
Fertilizers , Nitrogen-Fixing Bacteria , Azotobacter , Carbon , Fertilizers/analysis , Nitrogen/analysis , Nutrients , Phosphates , Soil , Soil Microbiology
9.
Onco Targets Ther ; 13: 1931-1939, 2020.
Article in English | MEDLINE | ID: mdl-32184628

ABSTRACT

BACKGROUND: Circulating tumor cells (CTCs) have become potential diagnostic biomarker for several types of cancer, including lung cancer. In this study, we aim to determine whether CTCs detected by CellCollector can be used for early-stage diagnosis of lung cancer. METHODS: In this study, we recruited 64 volunteers, among whom 44 were suspected lung cancer patients requiring surgical treatment and 20 were healthy volunteers. We simultaneously analyzed PD-L1 expression in CTCs isolated using the GILUPI CellCollector and copy number variation by next-generation sequencing (NGS). RESULTS: We enrolled a total of 44 patients with suspected lung cancer who required surgery and 20 healthy volunteers. The patients were classified into 4 groups based on their pathological results: benign disease, in situ cancer, microinvasive, and invasive. The CTCs detection rate for each group was 10.00% (1/10), 45% (5/11), 50% (7/14), and 67% (6/9), respectively. Among the patients with lung cancer, the CTCs detection rate increased with disease progression. The rate of CTCs positivity was 52.94% (18/34) in patients who were diagnosed with lung cancer by pathology and 10% (1/10) in patients with benign disease. CTCs were not detected in the control group. The area under the receiver operating characteristic (ROC) curve, a measure for distinguishing patients with primary lung cancer, was 0.715 (95% CI 0.549-0.880, P=0.041). The sensitivity and specificity of the in vivo CTCs detection strategy for the diagnosis of early-stage lung cancer were 52.94% and 90%, respectively. CTCs were associated with clinical pathology but not with the size and location of the nodules. CONCLUSION: CTCs isolation using the CellCollector in vivo detection method might be effective for distinguishing between benign and malignant nodules and may be used for early-stage diagnosis of lung cancer.

10.
Chemosphere ; 228: 485-494, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31051351

ABSTRACT

A dynamic analysis approach for determining nitrite production and consumption rates was established to systematically investigate the characteristics of nitrogen transformation and N2O emission of the completely autotrophic nitrogen removal over nitrite (CANON) process coupled with denitrification using a sequencing batch biofilm reactor (SBBR). The results indicate that anaerobic ammonium-oxidizing bacteria was not inhibited significantly by low C/N ratios. There were no obvious differences in the nitrite production rate, nitrite consumption rate or nitrogen removal among reactors operated with C/N ratios of 0, 0.67 and 1.00, which suggested that the certain carbon source did not significantly affect the nitrite conversion and nitrogen removal in the process. More than 60% of total N2O emission is generated during the initial phase of each period in the SBBR. More than 94.5% of N2O was generated by NO2--N consumption via denitrification in the process. Interestingly, total N2O production drops by 16.7%, when the C/N ratio increases from 0 to 1. This phenomenon may be caused by the inhibition of N2O production via AOB denitrification. Therefore, an appropriate carbon source (C/N = 1.00) has the beneficial effect of reducing N2O emission by CANON coupled with denitrification. The results of this study provide an important empirical foundation for the mitigation of N2O emission in the CANON process coupled with denitrification.


Subject(s)
Denitrification/genetics , Nitrites/chemistry , Nitrogen/chemistry
11.
Huan Jing Ke Xue ; 39(6): 2607-2614, 2018 Jun 08.
Article in Chinese | MEDLINE | ID: mdl-29965615

ABSTRACT

To investigate the pollution status of sediments at the junction of the Three Gorges Reservoir area, sediment samples were collected over four seasons from the junction of the estuary located at a tributary of the Ruxi River and the Yangtze River. The content of eight heavy metals (HMs), including Cr, Zn, Mn, Ni, Cu, As, Cd, and Pb, in sediments was determined by ICP-MS. The results showed the average levels of investigated HMs (in mg·kg-1) were Cr (45.24), Zn (46.46), Mn (406.14), Ni (20.885), Cu (12.49), As (7.02), Cd (0.253), and Pb (11.042). The distribution analysis indicated that the levels of HMs at the river mouth were higher than that of the tributaries of the middle reaches and the two sections nearby. The seasonal distribution shows that the heavy metal content in the spring sediment is higher than in summer, autumn and winter. In addition, the correlation analysis indicated that the eight HMs possessed similar homologous characteristics and had common exogenous inputs. The assessment of the Geo Accumulation Index showed slight Cd pollution in the estuary of Ruxi River, and the Potential Ecological Risk index showed that Cd presented moderate ecological risks. The toxic effect of benthonic organisms was possibly correlated to Ni contamination at the intersection of the tributary and main stream, which was supported by the evidence from the sediment quality criteria. In conclusion, the rating of ecological risk at the mouth of the Ruxi River tributary is slight.

12.
Appl Microbiol Biotechnol ; 102(16): 6973-6986, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29948113

ABSTRACT

The mitogen-activated protein kinase (MAPK) kinase Ste7 has a conserved Ser/Thr loop (S/T-X4(6)-S/T) that can activate the MAPK Fus3 or Kss1 for the regulation of pheromone response and filamentous growth in model yeast. Here, we show that not only the loop but also four C-terminal Ser/Thr residues are essential for Ste7 to function in the Fus3 cascade of Beauveria bassiana, a filamentous fungal insect pathogen. Mutagenesis of either looped S216/T220 or C-terminal S362 resulted in the same severe defects in conidial germination, hyphal growth, aerial conidiation, and submerged blastospore production as the ste7 deletion, followed by a complete loss of virulence and similarly increased cell sensitivities to osmotic salts, oxidants, heat shock and UV-B irradiation. Mutagenesis of three other Ser/Thr residues (S391, S440, and T485) also caused severe defects in most of the mentioned phenotypes. These defects correlated well with dramatically reduced transcript levels of some phenotype-related genes. These genes encode a transcription factor (CreA) essential for carbon/nitrogen assimilation, developmental activators (BrlA, AbaA, and WetA) and upstream transcription factor (FluG) required for conidiation, P-type N+/K+ ATPases (Ena1-5) required for intracellular N+/K+ homeostasis, and antioxidant enzymes involved in multiple stress responses. Our study unveils that the loop and four C-terminal Ser/Thr residues are all vital for the regulatory role of Ste7 in the growth, conidiation, virulence, and/or stress tolerance of B. bassiana and perhaps other filamentous fungi.


Subject(s)
Beauveria/physiology , Beauveria/pathogenicity , Mitogen-Activated Protein Kinases/metabolism , Reproduction, Asexual/genetics , Serine/metabolism , Threonine/metabolism , Virulence/genetics , Beauveria/enzymology , Beauveria/genetics , Fungal Proteins/genetics , Fungal Proteins/metabolism , Mitogen-Activated Protein Kinases/genetics , Spores, Fungal/metabolism , Stress, Physiological
13.
Environ Microbiol ; 20(4): 1590-1606, 2018 04.
Article in English | MEDLINE | ID: mdl-29575704

ABSTRACT

Rpd3 is a class I histone deacetylase that reverses lysine acetylation thus influencing cellular processes and functions. However, its role in fungal insect pathogens has not been explored yet. Here we show that Rpd3-dependent lysine modification and gene expression orchestrate growth, conidiation and virulence in Beauveria bassiana. Deletion of Rpd3 resulted in severe growth defects on various carbon/nitrogen sources, 97% reduction in conidiation capacity and drastic attenuation in virulence. These phenotypes concurred with differential expression of 1479 proteins and hyperacetylation or hypoacetylation of 2227 lysine residues on 1134 proteins. Many of these proteins fell into carbon/nitrogen metabolism and cell rescue/defence/virulence, indicating vital roles of Rpd3-dependent protein expression and lysine modification in the fungal growth and virulence. Intriguingly, lysine residues of four core histones (H2A, H2B, H3 and H4) and many histone acetyltransferases were also hyper- or hypoacetylated in Δrpd3, suggesting direct and indirect roles for Rpd3 in genome-wide lysine modification. However, crucial development activators were transcriptionally repressed and not found in either proteome or acetylome. Single/double-site-directed H3K9/K14 mutations for hyper/hypoacetylation exerted significant impacts on conidiation and dimorphic transition crucial for fungal virulence. Altogether, Rpd3 mediates growth, asexual development and virulence through transcriptional/translational regulation and posttranslational lysine modification in B. bassiana.


Subject(s)
Beauveria/growth & development , Beauveria/pathogenicity , Gene Expression Regulation, Fungal/genetics , Histone Deacetylases/genetics , Histones/metabolism , Acetylation , Lysine/metabolism , Protein Processing, Post-Translational/genetics , Proteome/metabolism , Virulence/genetics
14.
Molecules ; 22(10)2017 Oct 13.
Article in English | MEDLINE | ID: mdl-29027968

ABSTRACT

Dipeptidyl peptidase-IV (DPP-IV) inhibitory peptides were rapidly identified from Ruditapes philippinarum hydrolysate. The hydrolysate was fractionated by ethanol precipitation and preparative reverse phase high-performance liquid chromatography (RP-HPLC). The fraction which showed the highest DPP-IV inhibitory activity was then analyzed by a high-throughput nano-liquid chromatography electrospray ionization tandem mass spectrometry (nano-LC ESI-MS/MS) method, and the sequences of peptides were identified based on the MS/MS spectra against the Mollusca protein data from the UniProt database. In total, 50 peptides were identified. Furthermore, molecular docking was used to identify potential DPP-IV inhibitors from the identified peptides. Docking results suggested that four peptides: FAGDDAPR, LAPSTM, FAGDDAPRA, and FLMESH, could bind pockets of DPP-IV through hydrogen bonds, π-π bonds, and charge interactions. The four peptides were chemically synthesized and tested for DPP-IV inhibitory activity. The results showed that they possessed DPP-IV inhibitory activity with IC50 values of 168.72 µM, 140.82 µM, 393.30 µM, and >500 µM, respectively. These results indicate that R. philippinarum-derived peptides may have potential as functional food ingredients for the prevention of diabetes.


Subject(s)
Diabetes Mellitus/drug therapy , Dipeptidyl Peptidase 4/chemistry , Dipeptidyl-Peptidase IV Inhibitors/pharmacology , Peptides/pharmacology , Amino Acid Sequence/genetics , Animals , Bivalvia/chemistry , Chromatography, Reverse-Phase , Diabetes Mellitus/pathology , Dipeptidyl-Peptidase IV Inhibitors/chemistry , Humans , Molecular Docking Simulation , Peptides/chemistry , Tandem Mass Spectrometry
15.
Sci Rep ; 7: 44360, 2017 03 15.
Article in English | MEDLINE | ID: mdl-28295016

ABSTRACT

Lysine acetylation (Kac) events in filamentous fungi are poorly explored. Here we show a lysine acetylome generated by LC-MS/MS analysis of immunoaffinity-based Kac peptides from normal hyphal cells of Beauveria bassiana, a fungal entomopathogen. The acetylome comprised 283 Kac proteins and 464 Kac sites. These proteins were enriched to eight molecular functions, 20 cellular components, 27 biological processes, 20 KEGG pathways and 12 subcellular localizations. All Kac sites were characterized as six Kac motifs, including a novel motif (KacW) for 26 Kac sites of 17 unknown proteins. Many Kac sites were predicted to be multifunctional, largely expanding the fungal Kac events. Biological importance of identified Kac sites was confirmed through functional analysis of Kac sites on Pmt1 and Pmt4, two O-mannosyltransferases. Singular site mutations (K88R and K482R) of Pmt1 resulted in impaired conidiation, attenuated virulence and decreased tolerance to oxidation and cell wall perturbation. These defects were close to or more severe than those caused by the deletion of pmt1. The Pmt4 K360R mutation facilitated colony growth under normal and stressful conditions and enhanced the fungal virulence. Our findings provide the first insight into the Kac events of B. bassiana and their links to the fungal potential against insect pests.


Subject(s)
Beauveria/metabolism , Fungal Proteins/genetics , Hyphae/metabolism , Lysine/metabolism , Mannosyltransferases/genetics , Protein Processing, Post-Translational , Spores, Fungal/metabolism , Acetylation , Amino Acid Motifs , Animals , Beauveria/genetics , Beauveria/growth & development , Beauveria/pathogenicity , Fungal Proteins/metabolism , Gene Ontology , Gene Regulatory Networks , Hyphae/genetics , Hyphae/growth & development , Insect Control/methods , Insecta/microbiology , Mannosyltransferases/metabolism , Metabolic Networks and Pathways/genetics , Molecular Sequence Annotation , Mutation , Pest Control, Biological/methods , Proteome/genetics , Proteome/metabolism , Spores, Fungal/genetics , Spores, Fungal/growth & development , Virulence
16.
Environ Microbiol ; 19(5): 1808-1821, 2017 05.
Article in English | MEDLINE | ID: mdl-28076898

ABSTRACT

High-osmolarity glycerol (HOG) pathway required for yeast osmoregulation relies upon the mitogen-activated protein kinase (MAPK) Hog1 cascade that comprise the MAPKKKs Ssk2/Ssk22 and Ste11 converging on the MAPKK Pbs2. Here we show a Hog1 cascade with the unique MAPKKK Ssk2 acting in Beauveria bassiana. Hypersensitivity to high osmolarity and high resistance to fludioxonil fungicide appeared in Δssk2, Δpbs2 and Δhog1 mutants whereas the two hallmark phenotypes were reversed in Δste11. Increased sensitivity to heat shock and decreased sensitivity to cell wall perturbation also occurred in the three mutants but not in Δste11 although antioxidant phenotypes were different in all deletion mutants. Intriguingly, signals of Hog1 phosphorylation induced by osmotic, oxidative and thermal cues were present in Δste11 but absent in Δssk2 and Δpbs2. Moreover, vegetative growth on minimal media with different carbon/nitrogen sources was much more suppressed in Δste11 and Δssk2 than in Δpbs2 and Δhog1 although all mutants suffered similar, but severe, conidiation defects on a standard medium. Normal host infection was abolished in Δste11 while virulence was differentially attenuated in other mutants. Our findings exclude Ste11 from the Hog1 cascade that regulates multiple stress responses and environmental adaptation of B. bassiana and perhaps other filamentous fungi.


Subject(s)
Beauveria/metabolism , MAP Kinase Kinase Kinases/metabolism , Mitogen-Activated Protein Kinase Kinases/metabolism , Mitogen-Activated Protein Kinases/metabolism , Osmoregulation/physiology , Osmotic Pressure/physiology , Beauveria/pathogenicity , Cell Wall/metabolism , Fungal Proteins/genetics , Gene Deletion , Glycerol/metabolism , MAP Kinase Kinase Kinases/genetics , Mitogen-Activated Protein Kinase Kinases/genetics , Osmoregulation/genetics , Phenotype , Phosphorylation , Virulence
17.
PLoS One ; 11(4): e0153007, 2016.
Article in English | MEDLINE | ID: mdl-27055109

ABSTRACT

Cdc14 is a dual-specificity phosphatase that regulates nuclear behavior by dephosphorylating phosphotyrosine and phosphoserine/phosphothreonine in fungi. Previously, Cdc14 was shown to act as a positive regulator of cytokinesis, asexual development and multiple stress responses in Beauveria bassiana, a fungal insect pathogen. This study seeks to gain deep insight into a pivotal role of Cdc14 in the signaling network of B. bassiana by analyzing the Cdc14-specific proteome and phosphoproteome generated by the 8-plex iTRAQ labeling and MS/MS analysis of peptides and phosphopeptides. Under normal conditions, 154 proteins and 86 phosphorylation sites in 67 phosphoproteins were upregulated in Δcdc14 versus wild-type, whereas 117 proteins and 85 phosphorylation sites in 58 phosphoproteins were significantly downregulated. Co-cultivation of Δcdc14 with NaCl (1 M), H2O2 (3 mM) and Congo red (0.15 mg/ml) resulted in the upregulation / downregulation of 23/63, 41/39 and 79/79 proteins and of 127/112, 52/47 and 105/226 phosphorylation sites in 85/92, 45/36 and 79/146 phosphoproteins, respectively. Bioinformatic analyses revealed that Cdc14 could participate in many biological and cellular processes, such as carbohydrate metabolism, glycerophospholipid metabolism, the MAP Kinase signaling pathway, and DNA conformation, by regulating protein expression and key kinase phosphorylation in response to different environmental cues. These indicate that in B. bassiana, Cdc14 is a vital regulator of not only protein expression but also many phosphorylation events involved in developmental and stress-responsive pathways. Fourteen conserved and novel motifs were identified in the fungal phosphorylation events.


Subject(s)
Beauveria/enzymology , Cell Cycle Proteins/metabolism , Fungal Proteins/metabolism , MAP Kinase Signaling System/physiology , Phosphoproteins/metabolism , Stress, Physiological/physiology , Beauveria/genetics , Cell Cycle Proteins/genetics , Fungal Proteins/genetics , Phosphoproteins/genetics
18.
Int J Cancer ; 139(1): 164-70, 2016 Jul 01.
Article in English | MEDLINE | ID: mdl-26915723

ABSTRACT

Platelet to lymphocyte ratio (PLR) was recently reported as a useful index in predicting the prognosis of lung cancer. However, the prognostic role of PLR in lung cancer remains controversial. The aim of this study was to evaluate the association between PLR and clinical outcome of lung cancer patients through a meta-analysis. Relevant literatures were retrieved from PubMed, Ovid, the Cochrane Library and Web of Science databases. Meta-analysis was performed using hazard ratio (HR) and 95% confidence intervals (CIs) as effect measures. A total of 5,314 patients from 13 studies were finally enrolled in the meta-analysis. The summary results showed that elevated PLR predicted poorer overall survival (OS) (HR: 1.526, 95%CI: 1.268-1.836, p < 0.001) in patients with lung cancer and OS (HR: 1.631, 95%CI: 1.447-1.837, p < 0.001) in patients with nonsmall cell lung cancer (NSCLC). Subgroup analysis revealed that increased PLR was also associated with poor OS in NSCLC treated by surgical resection (HR: 1.884, 95%CI: 1.308-2.714, P < 0.001) and non-surgery (HR: 1.570, 95%CI: 1.323-1.863, P < 0.001). In addition, PLR Cut-off value ≤ 160 (HR: 1.506, 95%CI: 1.292-1.756, P < 0.001) and PLR Cut-off value>160 (HR: 1.842, 95%CI: 1.523-2.228, P < 0.001). In contrast, elevated PLR was not associated with OS (HR: 1.117, 95%CI: 0.796-1.569, P > 0.05) in patients with small cell lung cancer (SCLC).This meta-analysis result suggested that elevated PLR might be a predicative factor of poor prognosis for NSCLC patients.


Subject(s)
Blood Platelets/pathology , Carcinoma, Non-Small-Cell Lung/blood , Lymphocytes/pathology , Prognosis , Carcinoma, Non-Small-Cell Lung/pathology , Disease-Free Survival , Humans , Lymphocyte Count , Neutrophils/pathology , Proportional Hazards Models
19.
Onco Targets Ther ; 8: 3433-9, 2015.
Article in English | MEDLINE | ID: mdl-26640383

ABSTRACT

The diagnostic value of SHOX2 DNA methylation in patients with lung cancer remains controversial. Thus, we performed a systematic review and meta-analysis to assess diagnostic accuracy of SHOX2 DNA methylation in the lymph node, bronchial aspirates, pleural effusion, plasma, and tumor tissue for lung cancer. We conducted a comprehensive literature search in PubMed, Ovid, the Cochrane library, and Web of Science databases in May 2015. The diagnostic sensitivity (SEN), specificity (SPE), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curve were pooled using STATA 12.0 software. A total of 2,296 subjects included 1,129 lung cancer patients in eight studies were recruited in this meta-analysis. The summary estimates for SHOX2 DNA methylation in the diagnosis of lung cancer in these studies were pooled SEN =0.70 (95% confidence interval [CI]: 0.46-0.87), SPE =0.96 (95% CI: 0.91-0.99), PLR 20.01 (95% CI: 6.96-57.52), NLR 0.31 (95% CI: 0.15-0.64), and DOR 65.11 (95% CI: 13.10-323.61), and the area under the curve (AUC) was 0.96 (95% CI: 0.94-0.97). SHOX2 DNA methylation has greater diagnostic value in detecting lung cancer. In addition, considering the potential publication bias and high heterogeneity, further research studies with more well-designed and large sample sizes are needed in the future.

20.
Onco Targets Ther ; 8: 2731-8, 2015.
Article in English | MEDLINE | ID: mdl-26491346

ABSTRACT

BACKGROUND: Neutrophil to lymphocyte ratio (NLR) has recently been reported to be a poor prognostic indicator in lung cancer. However, the prognostic value of the NLR in patients with lung cancer still remains controversial. We performed a meta-analysis to evaluate the prognostic value of NLR in patients with lung cancer. METHODS: We performed a comprehensive literature search in PubMed, Ovid, the Cochrane Library, and Web of Science databases in May 2015. Studies were assessed for quality using the Newcastle-Ottawa Scale. RESULTS: Twenty-two studies with a total of 7,054 patients were included in this meta-analysis. The meta-analysis was performed to generate combined hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS). Our analysis results indicated that high NLR predicted poorer OS (HR, 1.51; 95% confidence interval [CI], 1.33-1.71; P<0.001) and PFS (HR, 1.33; 95% CI, 1.07-1.67; P=0.012) in patients with lung cancer. High NLR was also associated with poor OS in lung cancer treated by surgical resection (HR, 1.59; 95% CI, 1.26-1.99; P<0.001) and chemotherapy (HR, 1.15; 95% CI, 1.08-1.22; P<0.001). In addition, NLR cut-off value =5 (HR, 1.57; 95% CI, 1.16-2.12; P=0.003) and NLR cut-off value <5 (HR, 1.47; 95% CI, 1.28-1.69; P<0.001). CONCLUSION: This meta-analysis result suggested that NLR should have significant predictive ability for estimating OS and PFS in patients with lung cancer and may be as a significant biomarker in the prognosis of lung cancer.

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