Search

Toxoplasma gondii is a protozoan parasite capable of infecting a large number of warm-blooded animals and causes serious health complications in immunocompromised patients. T. gondii infection of the feline small intestine is critical for the completion of the life cycle and transmission of T. gondii. Protein acetylation is an important posttranslational modification, which plays roles in the regulation of various cellular processes. Therefore, understanding of how T. gondii reprograms the protein acetylation status of feline definitive host can help to thwart the production and spread of T. gondii. Here, we used affinity enrichment and high-resolution liquid chromatography with tandem mass spectrometry to profile the alterations of the acetylome in cat small intestine 10 days after infection by T. gondii Prugniuad (Pru) strain. Our analysis showed that T. gondii induced significant changes in the acetylation of proteins in the cat intestine. We identified 2606 unique lysine acetylation sites in 1357 acetylated proteins. The levels of 334 acetylated peptides were downregulated, while the levels of 82 acetylated peptides were increased in the infected small intestine. The proteins with differentially acetylated peptides were particularly enriched in the bioenergetics-related processes, such as tricarboxylic acid cycle, oxidative phosphorylation, and oxidation-reduction. These results provide the first baseline of the global acetylome of feline small intestine following T. gondii infection and should facilitate further analysis of the role of acetylated protein in the pathogenesis of T. gondii infection in its definitive host. [ABSTRACT FROM AUTHOR]

Diatoms are one of the predominant contributors to global carbon fixation by accounting for over 40% of total oceanic primary production and dominate export production. They play a significant role in marine biogeochemistry cycle. The diatom mat deposits are results of vast diatoms bloom. By analysis of diatom mats in 136°00′-140°00'E,15°00'?21°00'N, Eastern Philippines Sea, we identified the species of the diatoms as giant Ethmodiscus rex (Wallich) Hendey. AMS 14C dating shows that the sediments rich in diatom mats occurred during 16000-28600 a B.P., which means the bloom mainly occurred during the last glacial period, while there are no diatom mat deposits in other layers. Preliminary analysis indicates that Antarctic Intermediate Water (AAIW) expanded northward and brought silicate-rich water into the area, namely, silicon leakage processes caused the bloom of diatoms. In addition, the increase of iron input is one of the main reasons for the diatom bloom. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii secretes a group of rhoptry-secreted kinases (ROPs), which play significant roles in promoting intracellular infection. T. gondii rhoptry organelle protein 17 (ROP17) is one of these important effector proteins. However, its role in modulating host cell response during infection remains poorly understood. Here, we reveal that ROP17 (genotype I) induces significant changes in the expression genes and transcription factors of host cells. HEK293T cells were transfected with PCMV-N-HA-ROP17 plasmid or empty control PCMV-N-HA plasmid. Transcriptomic analysis revealed 3138 differentially expressed genes (DEGs) in PCMV-N-HA-ROP17-transfected HEK293T cells, including 1456 upregulated, 1682 downregulated DEGs. Also, 715 of the DEGs were transcription factors (TFs), including 423 downregulated TFs and 292 upregulated TFs. Most differentially expressed TFs, whether belong to signal transduction, cancer-related pathways or immune-related pathways, were downregulated in ROP17-expressing cells. ROP17 also decreased alternative splicing events in host cells, presumably via alteration of the expression of genes involved in the alternative splicing pathway. Taken together, our findings suggest a novel strategy whereby T. gondii ROP17 manipulates various cellular processes, including immune response through reprogramming host gene expression to promote its own colonization and survival in the infected host cells. [ABSTRACT FROM AUTHOR]

There is interest in cultivating an economic and controllable method for preparing biomass-based adsorptive materials for efficient removal of dyes from water. Herein a new bead-like material, i.e. alginate-derived carbon beads with a tailored hierarchical structure and surface chemistry, was prepared by using CaCO3-encapsulated calcium alginate (CA) hydrogel beads as the starting material and subsequent controllable carbonization and oxidation treatment. The resultant samples were characterized by SEM, TEM, FTIR, N2 sorption and XRD, etc. Analyses showed that hierarchical carbon beads with a tailored density of oxygen-containing functional groups have been successfully prepared. Adsorption of methylene blue (MB) was studied systematically through batch and column adsorption analyses, and noting the effect of pH, contact time, initial dye concentrations and flow rates. The adsorption kinetics and isotherms fitted well with the pseudo-second-order kinetic model and Langmuir isotherm model, respectively; and the maximum adsorption capacity for MB was 397.9 mg/g. The results indicated that CaCO3/CA-ox could not only significantly improve the adsorption capacity but also exhibited a higher adsorption rate for MB compared with CA. Furthermore, compared to traditional powdery materials, this bead-like porous adsorbent is convenient for column adsorption and scale-up for practical applications, due to the easy regeneration and reusability. [ABSTRACT FROM AUTHOR]

A rare earth ytterbium complex with 2,4,6-pyridinetricarboxylic acid (Hpta) has been synthesized by hydrothermal method, the formula is {[Yb(pta)(HO)]·HO}. The complex crystallized in monoclinic system, P2/c space group with lattice parameters a = 11.6556(19)Å, b = 7.8364(12), c = 22.020(4), α = γ = 90º, β = 92.120(3), Z = 4, GOF = 1.026, R1 = 0.0334, wR2 = 0.0660. The pta anions connect four rare earth Yb(III) ions with two different coordination modes. The complex exhibit intense characteristic near-infrared luminescence of Yb(III) ions at 990 nm with excitation of UV-rays. [ABSTRACT FROM AUTHOR]