Methods to optimize the production of gamma-aminobutyric acid （GABA） by Lactobacillus brevis CGMCC 1306 were investigated. Results indicated that cell growth was maximal at pH 5.0, while pH 4.5 was pref-erable to GA...Methods to optimize the production of gamma-aminobutyric acid （GABA） by Lactobacillus brevis CGMCC 1306 were investigated. Results indicated that cell growth was maximal at pH 5.0, while pH 4.5 was pref-erable to GABA formation. The optimal temperature for cell growth （35 °C） was lower than that for GABA forma-tion （40 °C）. In a two-stage pH and temperature control fermentation, cultures were maintained at pH 5.0 and 35 °C for 32 h, then adjusted to pH 4.5 and 40 °C, GABA production increased remarkably and reached 474.79 mmol·L-1 at 72 h, while it was 398.63 mmol·L-1 with one stage pH and temperature control process, in which cultivation con-ditions were constantly controlled at pH 5.0 and 35 °C. In order to avoid the inhibition of cell growth at higher L-monosodium glutamate （L-MSG） concentrations, the two-stage control fermentation with substrate feeding strat-egy was applied to GABA production, with 106.87 mmol （20 g） L-MSG supplemented into the shaking-flask at 32 h and 56 h post-inoculation separately. The GABA concentration reached 526.33 mmol·L-1 at 72 h with the fer-mentation volume increased by 38%. These results will provide primary data to realize large-scale production of GABA by L. brevis CGMCC 1306.展开更多
Background: Increasing evidence indicates that micro RNAs(mi RNAs) are involved in inflammatory response and immune regulation following pathogen invasion. The purpose of this study was to elucidate the roles played b...Background: Increasing evidence indicates that micro RNAs(mi RNAs) are involved in inflammatory response and immune regulation following pathogen invasion. The purpose of this study was to elucidate the roles played by Gallus gallus micro RNA-1306-5 p(gga-mi R-1306-5 p) in host responses against potential invasion by Salmonella enteritidis(SE) in chickens and the underlying mechanisms.Results: In present study, the expression levels of gga-mi R-1306-5 p were determined in both tissues and HD11 cells. The results showed that gga-mi R-1306-5 p was significantly increased following SE infection or lipopolysaccharide(LPS) stimulation. The dual luciferase reporter assay further validated that gga-mi R-1306-5 p targeted the Toll-interacting protein(Tollip), and thereby participated in the regulation of immune response against SE or LPS stimulation through binding with the 3′-untranslated region(3’UTR) of Tollip. Additionally, the expression of Tollip was significantly blocked by over-expressed gga-mi R-1306-5 p. The underlying mechanisms by which ggami R-1306-5 p modulated the production of pro-inflammatory cytokines were also investigated. Molecular biological assays demonstrated that overexpression of gga-mi R-1306-5 p promoted the production of pro-inflammatory mediators, including NF-κB, TNF-α, IL-6, and IL-1β, which produced effects similar to those of Tollip knockdown.Conclusions: Taken together, gga-mi R-1306-5 p induced by SE or LPS, regulates the immune response by inhibiting Tollip, which activates the production of inflammatory cytokines. This study has provided the first direct evidence that gga-mi R-1306-5 p targets Tollip, and is involved in the host response against SE.展开更多
基金Supported by the National＇Naturai Science Foundation of China （30970638, 21176220 and 31240054）, Zhejiang Provincial Natural Science Foundation （Z13B06008） and the National Basic Research Program of China （2007CB714305）.
文摘Methods to optimize the production of gamma-aminobutyric acid （GABA） by Lactobacillus brevis CGMCC 1306 were investigated. Results indicated that cell growth was maximal at pH 5.0, while pH 4.5 was pref-erable to GABA formation. The optimal temperature for cell growth （35 °C） was lower than that for GABA forma-tion （40 °C）. In a two-stage pH and temperature control fermentation, cultures were maintained at pH 5.0 and 35 °C for 32 h, then adjusted to pH 4.5 and 40 °C, GABA production increased remarkably and reached 474.79 mmol·L-1 at 72 h, while it was 398.63 mmol·L-1 with one stage pH and temperature control process, in which cultivation con-ditions were constantly controlled at pH 5.0 and 35 °C. In order to avoid the inhibition of cell growth at higher L-monosodium glutamate （L-MSG） concentrations, the two-stage control fermentation with substrate feeding strat-egy was applied to GABA production, with 106.87 mmol （20 g） L-MSG supplemented into the shaking-flask at 32 h and 56 h post-inoculation separately. The GABA concentration reached 526.33 mmol·L-1 at 72 h with the fer-mentation volume increased by 38%. These results will provide primary data to realize large-scale production of GABA by L. brevis CGMCC 1306.
基金supported by grants from the National Natural Science Foundation of China(No.31572393)the National Key Technology R&D Program(2015BAD03B03)+1 种基金the China Agricultural Science and Technology Innovation Project(ASTIPIAS04)the earmarked fund for Modern AgroIndustry Technology Research System(CARS-41)
文摘Background: Increasing evidence indicates that micro RNAs(mi RNAs) are involved in inflammatory response and immune regulation following pathogen invasion. The purpose of this study was to elucidate the roles played by Gallus gallus micro RNA-1306-5 p(gga-mi R-1306-5 p) in host responses against potential invasion by Salmonella enteritidis(SE) in chickens and the underlying mechanisms.Results: In present study, the expression levels of gga-mi R-1306-5 p were determined in both tissues and HD11 cells. The results showed that gga-mi R-1306-5 p was significantly increased following SE infection or lipopolysaccharide(LPS) stimulation. The dual luciferase reporter assay further validated that gga-mi R-1306-5 p targeted the Toll-interacting protein(Tollip), and thereby participated in the regulation of immune response against SE or LPS stimulation through binding with the 3′-untranslated region(3’UTR) of Tollip. Additionally, the expression of Tollip was significantly blocked by over-expressed gga-mi R-1306-5 p. The underlying mechanisms by which ggami R-1306-5 p modulated the production of pro-inflammatory cytokines were also investigated. Molecular biological assays demonstrated that overexpression of gga-mi R-1306-5 p promoted the production of pro-inflammatory mediators, including NF-κB, TNF-α, IL-6, and IL-1β, which produced effects similar to those of Tollip knockdown.Conclusions: Taken together, gga-mi R-1306-5 p induced by SE or LPS, regulates the immune response by inhibiting Tollip, which activates the production of inflammatory cytokines. This study has provided the first direct evidence that gga-mi R-1306-5 p targets Tollip, and is involved in the host response against SE.
