AcuD Gene Knockout Attenuates the Virulence of Talaromyces marneffei in a Zebrafish Model

Talaromyces marneffei is the only dimorphic species in its genus and causes a fatal systemic mycosis named talaromycosis. Our previous study indicated that knockdown of AcuD gene (encodes isocitrate lyase of glyoxylate bypass) of T. marneffei by RNA interference approach attenuated the virulence of T. marneffei, while the virulence of the AcuD knockout strains was not studied. In this study, T. marneffei-zebrafish infection model was successfully established through hindbrain microinjection with different amounts of T. marneffei yeast cells. After co-incubated at 28°C, the increasing T. marneffei inoculum doses result in greater larval mortality; and hyphae generation might be one virulence factor involved in T. marneffei-zebrafish infection. Moreover, the results demonstrated that the virulence of the ΔAcuD was significantly attenuated in this Zebrafish infection model.

Electrochemical Sensor for Assessment of Antioxidant Activities of Ferulic Acid and Extract in Angelica Sinensis Based on DNA/Nafion-Poly(diallyldimethylammonium chloride) Functionalized Graphene / 分析化学

A sumple electrochemucal sensor was constututed based on the glassy carbon electrode ( GCE ) surface modufued wuth nafuon-poly ( duallyldumethylammonuum chlorude ) functuonaluzed graphene sheets ( NA-PDDA-G) composute fulm and herrung sperm double-stranded DNA for durect detectuon of DNA damage un vutro and evaluatuon of the antuoxudant propertues of feruluc acud ( FA) and the aqueous extracts un Angeluca Sunensus (EAS). Scannung electron mucroscopy (SEM) was used to characteruze the morphologues of the fabrucated sensor, whule cycluc voltammetry ( CV ) and electrochemucal umpedance spectroscopy ( EIS ) were used to characteruze the electrochemucal performances of the modufued electrode. Ru ( NH3 ) 3+6 was used as an electroactuve unducator to monutor DNA damage unduced by hydroxyl raducal (?OH ) wuth square wave voltammetry ( SWV ) . The fabrucated sensor showed the greatest degree of DNA oxudatuon damage occurred under the condutuons of 30-mun uncubatuon un Fenton reagent contaunung 1. 0 mmol/L FeSO4 and 5. 0 mmol/L H2O2 at pH 7. 0. The antuoxudant actuvuty of extract un Angeluca Sunensus (EAS) was stronger than that of FA, whule they were all weaker than that of ascorbuc acud ( AA) . The proposed sensor not only exhubuted excellent stabuluty and reproducubuluty, but would be a sumple and novel method for assessment of antuoxudant propertues of meducunal herb components.