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Following fusion of a mycoplasma with a host cell membrane, the inserted components of mycoplasma may then be transported through the endocytic pathway. However, the effects of mycoplasmas on the host cell endomembrane system are largely unknown. In this study, mycoplasma induced changes in the dynamics of endocytic and autophagic systems were investigated. Endocytosis and autophagy are two major processes involved in the survival of intracellular prokaryotic pathogens. It was found that, immediately following infection, mycoplasmas induce endocytosis in the host cell; however, in the long term the mycoplasmas suppress turnover of the components of the endocytic pathway. Immunofluorescence microscopy revealed that Rab7 and LC3-II are recruited to the intracellular mycoplasma containing compartments. Western blot analysis and quantitative reverse transcription-polymerase chain reaction (qPCR) showed that mycoplasmas increase expression of Rab7 by upregulating transcription, but increase levels of LC3-II and p62 by post-translational regulation. Furthermore, it was demonstrated that mycoplasma infection causes inhibition of autophagic degradation of LC3-II and p62. In addition, it was found that upregulation of Rab7 and inhibition of autophagic degradation synergistically contributes to intracellular mycoplasma accumulation. In conclusion, these findings suggest that mycoplasmas may manipulate host cell endosomal and autophagic systems in order to facilitate intracellular infection. [ABSTRACT FROM AUTHOR]

The Mycoplasma genus comprises a group of microbes that cause persistent infection in humans and its role in promoting tumor development has long been a concern. Although mixtures of components isolated from Mycoplasma have been shown to activate host Rho family small GTPases and Stat3, no individual factor with this activity has been reported. In the current study, a conserved small GTPase-like protein fragment (SGLP) from Mycoplasma pulmonis chromosome partition protein, Smc, was identified as a virulence factor. SGLP was observed to interact with Rac1 and Stat3. The wild-type (wt) SGLP, which contains a WxxxE motif, induced activation of Rac1 and phosphorylation of Stat3 at the tyrosine-705 residue, while the SGLP mutant containing a mutation from WxxxE to AxxxA did not exert the same effects. Moreover, SGLP-induced Stat3 phosphorylation was observed to be dependent upon Rac1 activity. Furthermore, wt SGLP was observed to promote cell migration and increase bromodeoxyuridine incorporation in HeLa cells and the SGLP mutant did not elicit these effects in HeLa cells. In conclusion, the current observations suggest that SGLP is an important virulence factor of Mycoplasma, which contributes to tumor cell migration and proliferation in vitro via interaction with Rac1 and Stat3. [ABSTRACT FROM AUTHOR]

[Objective] The flavonoids were extracted from ginseng root and its antioxidant activity was studied. [Method] The method of ethanol reflow and polyamide enrichment were adopted in the extract of the flavonoids from ginseng root. The antioxidant of the flavonoids from ginseng root was tested with DPPH method. Fenton method and rats feeding. [Results] When the concentration of the ginseng root flavonoids was over 0.5 mg/mL. the scavenging rate of the DPPH free radical was more titan 80% and 0.6 mg/mL, the hydroxyl free radical, as high as 70.8%. The activity of SOD in rat brain could increase over 17.97% after the rat was fed with the flavonoids at the concentration of 80 - 120 mg/kg per day for five weeks. Conclusion The ginseng root flavonoids had a strong scavenging effect on DPPH free radical and hydroxyl free radical in vitro and also an intensifying effect on the activity of SOD in SD rat brain in vivo. [ABSTRACT FROM AUTHOR]

Examines the use of fluorous Boc carbamates in fluorous synthesis. Preparation of the first fluorous variants of the Boc group; Demonstration of the utility of the Boc group; Confirmation of the value of light serial fluorous chromatography.

Introduces a technique for the synthesis of mixtures of organic compounds that simultaneously solves both the separation and identification problems inherent in solution-phase mixture synthesis. Fluorous mixture synthesis; Quasiracemic synthesis; Parallel library synthesis.

Reports on the syntheses of triarylphosphines bearing both linear and branched fluorous tags. Characteristics of the phosphines; Organic solubility of platinum catalysts derived from the ligands; Removal of the fluorous components of the reaction mixtures by solid-phase extraction.

Applies a simple solid-liquid extraction procedure over fluorous reverse-phase silica gel for light fluorous synthesis. Separation of tagged and untagged products; Organic substrates; Tagged amino acids on nitrogen; Coupling of resulting acids; Use of two-stage filtration; Isolation of yield products for purity.

Pyruvate kinase (PK) deficiency is a rare genetic disease that causes chronic hemolytic anemia. There are currently no targeted therapies for PKdeficiency. Here,we describe the identification and characterization of AG-348, an allosteric activator ofPKthat is currently in clinical trials for the treatment of PK deficiency. We demonstrate that AG-348 can increase the activity of wild-type and mutant PK enzymes in biochemical assays and in patient red blood cells treated ex vivo. These data illustrate the potential for AG-348 to restore the glycolytic pathway activity in patients withPKdeficiencyand ultimately lead to clinical benefit. [ABSTRACT FROM AUTHOR]

Abstract: In order to observe mechanically driven proton flux in F0F1-ATPase coupled with artificial driven rotation on F1 simultaneously, a double channel observation system was established. An artificial δ-free F0F1-ATPase was constructed with α3, β3, ε, γ, and c n subunits as rotator and a, b2 as stator. The chromatophore was immobilized on the glass surface through biotin–streptavidin–biotin system, and the magnetic bead was attached to the β subunit of δ-free F0F1-ATPase. The mechanically driven proton flux was indicated by the fluorescence intensity change of fluorescein reference standard (F1300) and recorded by a cooled digital CCD camera. The mechanochemical coupling stoichiometry between F0 and F1 is about 4.15±0.2H+/rev when the magnetic field rotated at 0.33Hz (rps). [Copyright &y& Elsevier]

In order to observe mechanically driven proton flux in F(0)F(1)-ATPase coupled with artificial driven rotation on F(1) simultaneously, a double channel observation system was established. An artificial delta-free F(0)F(1)-ATPase was constructed with alpha(3), beta(3), epsilon, gamma, and c(n) subunits as rotator and a, b(2) as stator. The chromatophore was immobilized on the glass surface through biotin-streptavidin-biotin system, and the magnetic bead was attached to the beta subunit of delta-free F(0)F(1)-ATPase. The mechanically driven proton flux was indicated by the fluorescence intensity change of fluorescein reference standard (F1300) and recorded by a cooled digital CCD camera. The mechanochemical coupling stoichiometry between F(0) and F(1) is about 4.15 +/- 0.2H(+)/rev when the magnetic field rotated at 0.33 Hz (rps).