首页> 美国卫生研究院文献>other >Differential Growth of Francisella tularensis Which Alters Expression of Virulence Factors Dominant Antigens and Surface-Carbohydrate Synthases Governs the Apparent Virulence of Ft SchuS4 to Immunized Animals
【2h】

Differential Growth of Francisella tularensis Which Alters Expression of Virulence Factors Dominant Antigens and Surface-Carbohydrate Synthases Governs the Apparent Virulence of Ft SchuS4 to Immunized Animals

机译:图拉弗朗西斯菌的差异生长改变毒力因子优势抗原和表面碳水化合物合酶的表达控制着Ft SchuS4对免疫动物的明显毒力。

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务,本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文,但由于OA文献来源多样且变更频繁,仍可能出现获取不到、文献不完整或与标题不符等情况,如果获取不到我们将提供退款服务。请知悉。

摘要

The gram-negative bacterium Francisella tularensis (Ft) is both a potential biological weapon and a naturally occurring microbe that survives in arthropods, fresh water amoeba, and mammals with distinct phenotypes in various environments. Previously, we used a number of measurements to characterize Ft grown in Brain-Heart Infusion (BHI) broth as (1) more similar to infection-derived bacteria, and (2) slightly more virulent in naïve animals, compared to Ft grown in Mueller Hinton Broth (MHB). In these studies we observed that the free amino acids in MHB repress expression of select Ft virulence factors by an unknown mechanism. Here, we tested the hypotheses that Ft grown in BHI (BHI-Ft) accurately displays a full protein composition more similar to that reported for infection-derived Ft and that this similarity would make BHI-Ft more susceptible to pre-existing, vaccine-induced immunity than MHB-Ft. We performed comprehensive proteomic analysis of Ft grown in MHB, BHI, and BHI supplemented with casamino acids (BCA) and compared our findings to published “omics” data derived from Ft grown in vivo. Based on the abundance of ~1,000 proteins, the fingerprint of BHI-Ft is one of nutrient-deprived bacteria that—through induction of a stringent-starvation-like response—have induced the FevR regulon for expression of the bacterium's virulence factors, immuno-dominant antigens, and surface-carbohydrate synthases. To test the notion that increased abundance of dominant antigens expressed by BHI-Ft would render these bacteria more susceptible to pre-existing, vaccine-induced immunity, we employed a battery of LVS-vaccination and S4-challenge protocols using MHB- and BHI-grown Ft S4. Contrary to our hypothesis, these experiments reveal that LVS-immunization provides a barrier to infection that is significantly more effective against an MHB-S4 challenge than a BHI-S4 challenge. The differences in apparent virulence to immunized mice are profoundly greater than those observed with primary infection of naïve mice. Our findings suggest that tularemia vaccination studies should be critically evaluated in regard to the growth conditions of the challenge agent.
机译:革兰氏阴性菌弗朗西索菌(Ft)既是潜在的生物武器,又是天然存在的微生物,可在节肢动物,淡水变形虫和在不同环境中具有独特表型的哺乳动物中生存。以前,我们使用多种测量方法来描述在脑心输液(BHI)肉汤中生长的Ft的特征:(1)与感染细菌相比更相似;(2)与在Mueller中生长的Ft相比,在幼稚动物中的毒性更高欣顿肉汤(MHB)。在这些研究中,我们观察到MHB中的游离氨基酸通过未知机制抑制了某些Ft毒力因子的表达。在这里,我们测试了BHI中生长的Ft(BHI-Ft)准确显示出与报道的感染性Ft更相似的完整蛋白质组成的假设,并且这种相似性将使BHI-Ft更易于感染已有的疫苗-诱导的免疫力比MHB-Ft高。我们对MHB,BHI和补充了酪蛋白氨基酸(BCA)的BHI中生长的Ft进行了全面的蛋白质组学分析,并将我们的发现与已发表的体内生长Ft的“组学”数据进行了比较。根据约1000种蛋白质的丰度,BHI-Ft的指纹是营养缺乏的细菌之一,通过诱导严格饥饿样反应,已经诱导了FevR调控因子表达细菌的毒力因子,显性抗原和表面碳水化合物合酶。为了测试BHI-Ft表达的优势抗原的丰度增加会使这些细菌更容易受到预先存在的,疫苗诱导的免疫力的观念,我们采用了MVS和BHI-的LVS疫苗接种和S4攻击方案Ft S4。与我们的假设相反,这些实验表明,LVS免疫提供了一种感染屏障,对MHB-S4攻击的抵抗力明显强于BHI-S4攻击。免疫小鼠的表观毒力差异远大于未感染小鼠的初次感染时的差异。我们的发现表明,应对挑战性药物的生长条件进行严格的图拉血疫苗接种研究。

著录项

相似文献

  • 外文文献
  • 专利
代理获取

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号