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Lactobacillus rhamnosus GG SpaC pilin subunit binds to the carbohydrate moieties of intestinal glycoconjugates 
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下载免费PDF全文 Keita Nishiyama Shintaro Ueno Makoto Sugiyama Yuji Yamamoto Takao Mukai 《Animal Science Journal》2016,87(6):809-815
Lactobacillus rhamnosus GG (LGG) is a well‐established probiotic strain. The beneficial properties of this strain are partially dependent on its prolonged residence in the gastrointestinal tract, and are likely influenced by its adhesion to the intestinal mucosa. The pilin SpaC subunit, located within the Spa pili structure, is the most well studied LGG adhesion factor. However, the binding epitopes of SpaC remain largely unknown. The aim of this study was to evaluate the binding properties of SpaC to the carbohydrate moieties of intestinal glycoconjugates using a recombinant SpaC protein. In a competitive enzyme‐linked immunosorbent assay, SpaC binding was markedly reduced by addition of purified mucin and the mucin oligosaccharide fraction. Histochemical staining revealed that the binding of SpaC was drastically reduced by periodic acid treatment. Moreover, in the surface plasmon resonance‐based Biacore assay, SpaC bound strongly to the carbohydrate moieties containing β‐galactoside at the non‐reducing terminus of glycolipids. We here provide the first demonstration that SpaC binds to the oligosaccharide chains of mucins, and that the carbohydrate moieties containing β‐galactoside at the non‐reducing termini of glycoconjugates play a crucial role in this binding. Our results demonstrate the importance of carbohydrates of SpaC for mucus interactions. 相似文献
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hrpE基因在水稻条斑病菌Hrp pilus形成和致病性中起重要作用 总被引：1，自引：0，他引：1
水稻条斑病菌(Xanthomonas oryzae pv.oryzicola,Xooc)的hrp(hypersensitive response and pathogenicity)基因簇编码形成Ⅲ型分泌系统(T3SS),将致病性的效应分子通过HrpF转位装置注入水稻细胞中,从而导致水稻产生抗(感)病性,但Xooc的HrpE是否形成Hrp pilus还不清楚。本研究对Xooc的hrpE基因进行突变,发现hrpE突变体在水稻上丧失致病性和在烟草上丧失激发HR的能力。与水稻互作结果显示,hrpE突变体不能够与水稻细胞互作,其在水稻组织中的生长能力显著下降。电镜结果显示,hrpE突变体不能够形成Hrp pilus,从而导致水稻条斑病菌丧失在水稻上的致病性。功能互补结果显示,完整的hrpE基因可以恢复hrpE突变体在烟草上激发HR反应的能力、在水稻上的致病性以及在水稻薄壁细胞间形成Hrp pilus的能力,表明hrpE基因形成Hrp pilus是水稻条斑病菌分泌致病性效应分子的重要条件。 相似文献
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应用８株鸡病原性大肠杆菌研究了菌毛作为分型抗原和共粘附特性,以抗Ⅰ型菌毛单克隆抗体（单抗）ｂＧ５和甘露糖进行了抑制作用试验。在血凝试验中、单抗和甘露糖都能抑制血凝反应,说明这些株都属于Ⅰ型,通过以单抗或甘露糖的粘附抑制程序这些Ｅｃｏｌｉ株对鸡气管上皮都不能特异粘附。 相似文献
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鸡大肠杆菌Ⅰ型菌毛亚单位苗交叉保护的初步研究 总被引：1，自引：0，他引：1
含Ⅰ型菌毛的３ 个不同血清型（Ｏ１ 、Ｏ７８ 及Ｏ８８） 的菌株， 大容量培养后提取菌毛制备３ 种单价菌毛油乳苗。用１ 日龄雏鸡分别免疫３ 种单价菌毛油乳剂苗， 每雏免疫量为１２５ μｇ ， 隔离饲养至２ 周龄经气囊攻毒， 并评价疫苗的免疫原性。结果未免疫鸡出现８７－５ ％ ～１００ ％ 的死亡率， 免疫鸡用同源菌株攻毒后死亡率仅１２－５ ％ ， 用异源菌株攻毒出现３７－５％ ～６２－５ ％ 的死亡率。免疫鸡攻毒后未死亡者， 经扑杀观察， 可见在气囊、心包及肝脏的病变非常轻微， 且攻毒后比非免疫鸡能更有效地清除攻入气囊的大肠杆菌 相似文献
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对一株牛源大肠杆菌JS株的菌体抗原及菌毛特性进行了研究。大肠杆菌JS株在Minca培养基上37℃培养18～24h,能够同时良好地表达菌毛抗原K99和F41。采用保温法和裂解法进行了菌毛提纯,取得了较好的效果。应用玻片凝集试验﹑抗D-甘露糖微量血凝试验(MRHA)进行菌毛特异性和粘附性研究。结果表明,K99、F41两种菌毛抗原不存在交叉凝集反应,其血凝谱能凝集牛﹑鸡的红细胞。 相似文献
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以5％绵羊血改良Minca琼脂筛选和克隆表达良好的K88^＋菌株，改良Minca琼脂培养获得K88菌液。用加热法及高速匀浆法使K88纤毛从菌体上脱下。饱和硫酸铵沉淀粗提，用Sepharose CL-4B凝胶过滤纯化K88抗原。提纯的抗原经SDS—PAGE电泳测定其分子量约为25000，且仅此一条蛋白带；与K88抗血清进行琼脂扩散试验只出现一条沉淀线。用提纯的抗原经多次免疫家兔制备了K88抗血清。抗血清在玻板凝集试验中只凝集K88菌株，不凝集K99，987P或F41菌株；在琼扩试验中，只与K88粗提抗原出现一条沉淀线，且效价为1：64，而不与K99，987P抗原出现沉淀线；在免疫电泳试验中，与无细胞K88纤毛液只出现一条沉淀线。鉴定结果表明，所制备的K88血清特异性强、效价高，可作为单因子血清用于凝集试验、琼扩试验等血清学试验，对K88菌株进行鉴定，对K88纤毛抗原进行定性和定量检测。 相似文献
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柑桔黄龙病菌菌毛形成蛋白(pilus formation protein, 408)是一种丰度较高的分泌蛋白。以感染柑桔黄龙病(HLB)的海南琼海市绿橙叶片为材料提取总DNA,利用408基因的特异引物进行PCR扩增,获得该基因的目的片段。序列分析结果表明海南琼海黄龙病菌408基因与柑桔黄龙病菌亚洲种psy62株系 (GenBank登录号:CP001677.5)408基因序列一致。功能预测结果表明其含有一个与菌毛形成相关的N端结构域,以及C端含有两个高度保守的基序(Motif 1和Motif 2)。通过Eco R Ⅴ和Xho Ⅰ双酶切构建重组载体p ET32a-408并将其转化BL21(DE3)大肠杆菌。重组菌经终浓度为1 mmoL/L IPTG诱导,目的蛋白主要以包涵体形式表达。目的蛋白经Ni2+-NTA层析柱纯化,并以此为抗原,腹腔免疫小白鼠,获得效价在1∶500～1∶10000的多克隆抗血清;Western blot进一步分析表明,408蛋白多克隆抗血清特异性强。研究结果为柑桔黄龙病菌408蛋白功能研究和柑桔黄龙病菌的蛋白检测产品开发提供重要科学依据。 相似文献
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Yilang Li Yichao Yan Songge Deng Cuiping Zhang Fazal Haq Tao Chen Yingbin Li Shengzhang Li Rihuan Yang Lifang Zou Gongyou Chen 《Plant pathology》2020,69(4):744-755
The gram-negative plant pathogen Xanthomonas oryzae pv. oryzae (Xoo) is able to infect the host rice and effectively colonize in vascular tissues. The type IV pilus (T4P) is one of the major virulence factors playing an important role in migration of Xoo through host vascular tissues. Here, we identified PilN, a T4P alignment subcomplex protein, which is involved in regulation of swimming motility, and analysed its contribution to bacterial surface-associated behaviours and virulence. We found that the pilN deletion mutant exhibited dramatically reduced twitching motility and scarcely detectable levels of T4P major pili PilA, as well as enhanced biofilm formation and exopolysaccharide (EPS) production. In addition, deletion of the pilN gene in Xoo resulted in impaired virulence in host rice and attenuated type III secretion system (T3SS) genes expression, which is independent of PilA assembly. Expression of the relevant pilN gene in trans was capable of restoring twitching motility and biofilm formation to the wild-type levels in the pilN mutant but partially recovering EPS production and virulence. Moreover, the expression of trh and xrvA genes, which encode the HrpG positive regulators, was decreased in the pilN mutant. Our results suggest that PilN executes versatile functions in bacterial virulence and cell surface-associated behaviours. 相似文献
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