In recent years,researches on food components with anti-allergic effects have been gathering attention,because of the expectation for the establishment of a safe and effective treatment for food allergy.Previous studi...In recent years,researches on food components with anti-allergic effects have been gathering attention,because of the expectation for the establishment of a safe and effective treatment for food allergy.Previous studies have reported that Lactiplantibacillus plantarum 22A-3 (LP22A3) inhibited degranulation of mast cells and reduced IgE production.We have developed a gastrointestinal allergy system in which mice are sensitized by intraperitoneal and oral administration of OVA and then challenged by oral administration of high doses of OVA.As a result,an increase in the amount of IgE in the blood and a decrease in the temperature of the colon were confirmed,and it was clarified that food allergy was induced by oral administration of high dose of OVA as the challenge.Oral administration of LP22A3 ameliorated allergic responses significantly by reducing the amount of IgE in the blood and to recovered the decrease of rectal temperature.However,LP22A3 did not affect the intestinal barrier function.Administered LP22A3 significantly suppressed mRNA expression of OX40L and IL-4.These results suggested that LP22A3 suppressed Th2 differentiation and IL-4 production via downregulation of OX40L,and consequently suppressed IgE production.LP22A3 might provide a safe and effective treatment for allergic diseases due to ability modulating intestinal immune system.展开更多
Halorhodospira(Hlr.)halochloris is a triply extremophilic phototrophic purple sulfur bacterium,as it is thermophilic,alkaliphilic,and extremely halophilic.The light-harvesting-reaction center(LH1–RC)core complex of t...Halorhodospira(Hlr.)halochloris is a triply extremophilic phototrophic purple sulfur bacterium,as it is thermophilic,alkaliphilic,and extremely halophilic.The light-harvesting-reaction center(LH1–RC)core complex of this bacterium displays an LH1-Q_(y)transition at 1,016 nm,which is the lowest-energy wavelength absorption among all known phototrophs.Here we report the cryo-EM structure of the LH1–RC at 2.42?resolution.The LH1 complex forms a tricyclic ring structure composed of 16αβγ-polypeptides and oneαβ-heterodimer around the RC.From the cryo-EM density map,two previously unrecognized integral membrane proteins,referred to as protein G and protein Q,were identified.Both of these proteins are single transmembrane-spanning helices located between the LH1 ring and the RC Lsubunit and are absent from the LH1–RC complexes of all other purple bacteria of which the structures have been determined so far.Besides bacteriochlorophyll b molecules(B1020)located on the periplasmic side of the Hlr.halochloris membrane,there are also two arrays of bacteriochlorophyll b molecules(B800 and B820)located on the cytoplasmic side.Only a single copy of a carotenoid(lycopene)was resolved in the Hlr.halochloris LH1–α3β3 and this was positioned within the complex.The potential quinone channel should be the space between the LH1–α3β3 that accommodates the single lycopene but does not contain aγ-polypeptide,B800 and B820.Our results provide a structural explanation for the unusual Q_(y)red shift and carotenoid absorption in the Hlr.halochloris spectrum and reveal new insights into photosynthetic mechanisms employed by a species that thrives under the harshest conditions of any phototrophic microorganism known.展开更多
文摘In recent years,researches on food components with anti-allergic effects have been gathering attention,because of the expectation for the establishment of a safe and effective treatment for food allergy.Previous studies have reported that Lactiplantibacillus plantarum 22A-3 (LP22A3) inhibited degranulation of mast cells and reduced IgE production.We have developed a gastrointestinal allergy system in which mice are sensitized by intraperitoneal and oral administration of OVA and then challenged by oral administration of high doses of OVA.As a result,an increase in the amount of IgE in the blood and a decrease in the temperature of the colon were confirmed,and it was clarified that food allergy was induced by oral administration of high dose of OVA as the challenge.Oral administration of LP22A3 ameliorated allergic responses significantly by reducing the amount of IgE in the blood and to recovered the decrease of rectal temperature.However,LP22A3 did not affect the intestinal barrier function.Administered LP22A3 significantly suppressed mRNA expression of OX40L and IL-4.These results suggested that LP22A3 suppressed Th2 differentiation and IL-4 production via downregulation of OX40L,and consequently suppressed IgE production.LP22A3 might provide a safe and effective treatment for allergic diseases due to ability modulating intestinal immune system.
基金supported in part by the National Key R&D Program of China(No.2022YFC3401800)National Natural Science Foundation of China(32070264)+5 种基金Shandong Provincial Natural Science Foundation(ZR2019ZD48)the Strategic Priority Research Program of CAS(XDA26050402)the Science&Technology Specific Project in Agricultural High-tech Industrial Demonstration Area of the Yellow River Delta(2022SZX12)the Innovation Center for Academicians of Hainan Provincethe Specific Research Fund of the Innovation Center for Academicians of Hainan Province(No.YSPTZX202309)supported in part by NASA Cooperative Agreement 80NSSC21M0355。
文摘Halorhodospira(Hlr.)halochloris is a triply extremophilic phototrophic purple sulfur bacterium,as it is thermophilic,alkaliphilic,and extremely halophilic.The light-harvesting-reaction center(LH1–RC)core complex of this bacterium displays an LH1-Q_(y)transition at 1,016 nm,which is the lowest-energy wavelength absorption among all known phototrophs.Here we report the cryo-EM structure of the LH1–RC at 2.42?resolution.The LH1 complex forms a tricyclic ring structure composed of 16αβγ-polypeptides and oneαβ-heterodimer around the RC.From the cryo-EM density map,two previously unrecognized integral membrane proteins,referred to as protein G and protein Q,were identified.Both of these proteins are single transmembrane-spanning helices located between the LH1 ring and the RC Lsubunit and are absent from the LH1–RC complexes of all other purple bacteria of which the structures have been determined so far.Besides bacteriochlorophyll b molecules(B1020)located on the periplasmic side of the Hlr.halochloris membrane,there are also two arrays of bacteriochlorophyll b molecules(B800 and B820)located on the cytoplasmic side.Only a single copy of a carotenoid(lycopene)was resolved in the Hlr.halochloris LH1–α3β3 and this was positioned within the complex.The potential quinone channel should be the space between the LH1–α3β3 that accommodates the single lycopene but does not contain aγ-polypeptide,B800 and B820.Our results provide a structural explanation for the unusual Q_(y)red shift and carotenoid absorption in the Hlr.halochloris spectrum and reveal new insights into photosynthetic mechanisms employed by a species that thrives under the harshest conditions of any phototrophic microorganism known.
