Role of Fibroblast Growth Factor 19 in Maintaining Nutrient Homeostasis and Disease

Fibroblast growth factor 19 （FGF19） is a kind of gut-derived postprandial hormone. As an atypical member of the FGF family, FGF19 functions as an endocrine hormone except regulating cell growth and differentiation. FGF19 plays a key role in coordination of liver bile acid biosynthesis and gallbladder motility, and acts as a regulator of metabolic homeostasis, including strengthening insulin sensitivity, decreasing triglyceride concentration and reducing body weight.

The transcription factor FgNsf1 regulates fungal development,virulence and stress responses in Fusarium graminearum

Nutrient and stress factor 1(Nsf1),a transcription factor containing the classical Cys2-His2(C_(2)H_(2))zinc finger motif,is expressed under non-fermentable carbon conditions and in response to salt stress in Saccharomyces cerevisiae.However,the role of Nsf1 in filamentous fungi is not well understood.In this study,the orthologue of Nsf1 was investigated in Fusarium graminearum(named FgNsf1),a causal agent of Fusarium head blight(FHB).The functions of FgNsf1 were evaluated by constructing a FgNSF1 deletion mutant,designated asΔFgNsf1,and its functional complementation mutantΔFgNsf1-C.Gene deletion experiments showed that the mycelial growth rate,asexual and sexual reproduction ofΔFgNsf1 were significantly reduced,but the pigment production ofΔFgNsf1 was remarkably increased compared with the PH-1 andΔFgNsf1-C.In addition,the tolerance ofΔFgNsf1 to osmotic pressures,cell wall-damaging agents and oxidative stress increased significantly.Sensitivity tests to different fungicides revealed thatΔFgNsf1 exhibited increased sensitivity to carbendazim(MBC)and tebuconazole,and enhanced tolerance to fludioxonil and iprodione than PH-1 andΔFgNsf1-C.The virulence ofΔFgNsf1 to wheat coleoptiles and flowering wheat heads were dramatically decreased,which was consistent with the decrease in the yield of deoxynivalenol(DON).All of these defects were restored by target gene complementation.These results indicated that FgNsf1 plays a crucial role in vegetative growth,asexual and sexual reproduction,stress responses,fungicide sensitivity,and full virulence in F.graminearum.

Optimization of Hydrocarbons Biodegradation by Bacterial Strains Isolated from Wastewaters in Ouagadougou, Burkina Faso: Case Study of SAE 40/50 Used Oils and Diesel

Environmental pollution with petroleum and petrochemical products such as diesel and used oils has been recognized as one of the most serious current problem in the world, especially in developing countries. These petrochemical products devastate the soil, surface and underground waters and alter the microbial population at the polluted sites. Thus, the present work aims to optimize the biodegradation of diesel and two used oils (SAE 40 and SAE 50) by bacterial strains namely Acinetobacter S2 and Pseudomonas S7 using either nutrient factors (yeast extract, peptone or trace elements) or surfactants (tween 80 or Sodium Dodecyl Sulfate: SDS). The strains are incubated alone or together with the used oils or diesel supplemented or not with nutrient factors or surfactants for 14, 28, 42 and 56 days, respectively. For all the incubation period, the hydrocarbons degradation rates are determined by gravimetric assay. The results obtained show that nutrient factors increase significantly SAE 50 used oil biodegradation (p = 0.009). Similarly, tween 80 increases SAE 50 and SAE 40 used oils biodegradation but not diesel one. The results also show a significant difference between biodegradation rates at 14, 28, 42 and 56 days for all the hydro-carbons tested (p Acinetobacter S2 and Pseudomonas S7 increases the degradation over the one of the strains alone.