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A defined mixed bioleaching consortium (constructed by Acidithiobacills ferrooxidans ATCC 23270, Leptospirillum ferriphilum YSK, Sulfobacillus thermosulfidooxidans ST, Acidithiobacills thiooxidans A01 and Acidithiobacills caldus S1) was used to investigate the fluoride stress response. The results showed that its growth and iron oxidation rate were obviously inhibited, while the sulphur oxidation was only barely restrained. Furthermore, the community dynamics and gene expression were assayed respectively by using real-time quantitative polymerase chain reaction assay (RT-PCR) and functional gene arrays (FGAs). From the analysis of community dynamics, the most obviously inhibited strains were S. thermosulfidooxidans ST, while L. ferriphilum YSK still maintained stable growth. After 4.8 mM of fluoride stress for 28 h, the S. thermosulfidooxidans cell concentration was decreased by about 517.8 times more than in non-stress state. From the analysis of gene expression, fluoride stress was seen to exert pleiotropic effects on different species in the consortium. The dominant species played the pivotal role in resisting fluoride stress and maintaining activities in the system, yet the inferior species also had a critical function of assisting the survival of the dominant species. [ABSTRACT FROM AUTHOR]

Background: Exosomes secreted by tumor cells contain specific antigens that may have immunotherapeutic purposes. The aim of this study was to characterize the proteomic content of lymphoma cell-derived exosomes (LCEXs)., Methods: In this study, exosomes derived from Raji cells (EXO(Raji)) were purified and proteins of EXO(Raji) were separated by one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis. Protein bands were identified by mass spectrometry. The protein components of EXO(Raji) were analyzed using shotgun technology, and the function proteins of EXO(Raji) were defined and described using the Gene Ontology (GO) database and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis., Results: A total of 197 proteins were identified in EXO(Raji); 139 proteins were also identified in Raji cells, showing an overlap of 70.56% of the total proteins in EXO(Raji). Interestingly, the remaining 58 proteins were unique to EXO(Raji). The GO database and KEGG were used to define and describe the function of proteins. The data showed that some important proteins involved in antigen procession and presentation as well as cell migration and adhesion were also identified in EXO(Raji), such as MHC-I and II, HSC70, HSP90, and ICMA-1., Conclusions: LCEXs express a discrete set of proteins involved in antigen presentation and cell migration and adhesion, suggesting that LCEXs play an important role in the regulation of immunity and interaction between lymphoma cells and their microenvironment. LCEXs harbor most of the proteins of lymphoma cells and could be one of the sources of lymphoma-associated antigens for immunotherapeutic purposes.

Background: Acidithiobacillus thiooxidans (A. thiooxidans), a chemolithoautotrophic extremophile, is widely used in the industrial recovery of copper (bioleaching or biomining). The organism grows and survives by autotrophically utilizing energy derived from the oxidation of elemental sulfur and reduced inorganic sulfur compounds (RISCs). However, the lack of genetic manipulation systems has restricted our exploration of its physiology. With the development of high-throughput sequencing technology, the whole genome sequence analysis of A. thiooxidans has allowed preliminary models to be built for genes/enzymes involved in key energy pathways like sulfur oxidation., Results: The genome of A. thiooxidans A01 was sequenced and annotated. It contains key sulfur oxidation enzymes involved in the oxidation of elemental sulfur and RISCs, such as sulfur dioxygenase (SDO), sulfide quinone reductase (SQR), thiosulfate:quinone oxidoreductase (TQO), tetrathionate hydrolase (TetH), sulfur oxidizing protein (Sox) system and their associated electron transport components. Also, the sulfur oxygenase reductase (SOR) gene was detected in the draft genome sequence of A. thiooxidans A01, and multiple sequence alignment was performed to explore the function of groups of related protein sequences. In addition, another putative pathway was found in the cytoplasm of A. thiooxidans, which catalyzes sulfite to sulfate as the final product by phosphoadenosine phosphosulfate (PAPS) reductase and adenylylsulfate (APS) kinase. This differs from its closest relative Acidithiobacillus caldus, which is performed by sulfate adenylyltransferase (SAT). Furthermore, real-time quantitative PCR analysis showed that most of sulfur oxidation genes were more strongly expressed in the S0 medium than that in the Na2S2O3 medium at the mid-log phase., Conclusion: Sulfur oxidation model of A. thiooxidans A01 has been constructed based on previous studies from other sulfur oxidizing strains and its genome sequence analyses, providing insights into our understanding of its physiology and further analysis of potential functions of key sulfur oxidation genes.

Background: Inflammatory mechanisms are important in stroke risk, and genetic variations in components of the inflammatory response have been implicated as risk factors for stroke. We tested the inflammatory gene polymorphisms and their association with ischemic stroke in a Chinese Han population., Methods: A total of 1,124 ischemic stroke cases and 1,163 controls were genotyped with inflammatory panel strips containing 51 selected inflammatory gene polymorphisms from 35 candidate genes. We tested the genotype-stroke association with logistic regression model., Results: We found two single nucleotide polymorphisms (SNPs) in CCL11 were associated with ischemic stroke. After adjusting for multiple testing using false discovery rate (FDR) with a 0.20 cut-off point, CCL11 rs4795895 remained statistically significant. We further stratified the study population by their hypertension status. In the hypertensive group, CCR2 rs1799864, CCR5 rs1799987 and CCL11 rs4795895 were nominally associated with increased risk of stroke. In the non-hypertensive group, CCL11 rs3744508, LTC4S rs730012, FCER1B rs569108, TGFB1 rs1800469, LTA rs909253 and CCL11 rs4795895 were associated with ischemic stroke. After correction for multiple testing, CCR2 rs1799864 and CCR5 rs1799987 remained significant in the hypertensive group, and CCL11 rs3744508, LTC4S rs730012, FCER1B rs569108, TGFB1 rs1800469, LTA rs909253 remained significant in the non-hypertensive group., Conclusions: Our results indicate that inflammatory genetic variants are associated with increased risk of ischemic stroke in a Chinese Han population, particularly in non-hypertensive individuals.