Low-shear force associated with modeled microgravity and spaceflight does not similarly impact the virulence of notable bacterial pathogens.
Low-shear force associated with modeled microgravity and spaceflight does not similarly impact the virulence of notable bacterial pathogens.
复制标题
DOI：
10.1007/s00253-014-6025-8
复制
发表时间：
2014-11
影响因子：
5
通讯作者：
Chopra, Ashok K.
中科院分区：
文献类型：
--
作者：
Rosenzweig, Jason A.;Ahmed, Sandeel;Eunson, John, Jr.;Chopra, Ashok K.
关键词：
随着环境的变化，微生物会经历各种威胁和压力源，在竞争激烈的微生物世界中，活力和对这种变化的快速反应能力使微生物能够与寻求营养的邻居竞争。从这个角度来看，微生物的生死取决于有效的应激反应机制。除了更常见的温度、营养和化学胁迫外，研究已经开始描述微生物对物理胁迫（即低剪切胁迫）的反应。事实上，微生物对低剪切模拟微重力（LSMMG）的反应，模拟了太空中的微重力，已经在原核生物和真核生物中进行了相当广泛的研究。有趣的是，lsmmg诱导了几种革兰氏阴性肠道细菌的毒力潜力的变化，例如，结扎小鼠回肠袢中肠毒素大肠杆菌介导的液体分泌增加，粘附性大肠杆菌介导的cco -2细胞的侵袭性增加，鼠伤寒沙门氏菌介导的上皮细胞和巨噬细胞的侵袭性增加，以及通过腹腔途径感染BALB/c小鼠鼠伤寒沙门氏菌的高毒力表型。虽然这些是细菌毒力增加的一些例子，但也有一些例子表明，在LSMMG下，生物体的毒力降低，例如，细胞培养感染中鼠疫耶尔森菌的低毒力，以及秀丽隐杆线虫感染模型中耐甲氧西林的金黄色葡萄球菌、粪肠球菌和单核细胞增生李斯特菌的低毒力。总的来说，一些暴露于lsmmg的细菌（但不是全部）似乎能够更好地应对随后的应激源，如渗透休克、酸休克、热休克和暴露于化疗药物。这篇小型综述主要讨论了lsmmg诱导的以及真正的太空飞行特异性细菌毒力潜力的变化，表明病原体对低剪切力的反应差异很大。最终，有必要仔细描述许多细菌病原体对低剪切力的反应，以评估这种物理压力如何影响细菌毒力的更完整的图景，因为“一刀切”的反应显然不是这样的。
As their environments change, microbes experience various threats and stressors, and in the hyper-competitive microbial world, dynamism and the ability to rapidly respond to such changes allow microbes to outcompete their nutrient-seeking neighbors. Viewed in that light, the very difference between microbial life and death depends on effective stress-response mechanisms. In addition to the more commonly studied temperature, nutritional, and chemical stressors, research has begun to characterize microbial responses to physical stress, namely low-shear stress. In fact, microbial responses to low shear modeled microgravity (LSMMG), which emulates the microgravity experienced in space, have been studied quite widely in both prokaryotes and eukaryotes. Interestingly, LSMMG-induced changes in the virulence potential of several Gram-negative enteric bacteria, e.g., an increased enterotoxigenic Eschericia coli-mediated fluid secretion in ligated ileal loops of mice, an increased adherent invasive E. coli-mediated infectivity of Caco-2 cells, an increased Salmonella Typhimurium-mediated invasion of both epithelial and macrophage cells, and S. Typhimurium hypervirulence phenotype in BALB/c mice when infected by the intraperitoneal route. Although these were some examples where virulence of the bacteria was increased, there are instances where organisms became less virulent under LSMMG, e.g., hypovirulence of Yersinia pestis in cell culture infections and hypovirulence of methicillin-resistant-Staphylococcus aureus, Enterococcus faecalis, and Listeria monocytogenes in a Caenorhabditis elegans infection model. In general, a number of LSMMG-exposed bacteria (but not all) seemed better equipped to handle subsequent stressors such as osmotic shock, acid shock, heat shock, and exposure to chemotherapeutics. This mini-review primarily discusses both LSMMG-induced as well as bonafide spaceflight-specific alterations in bacterial virulence potential, demonstrating that pathogens' responses to low-shear forces vary dramatically. Ultimately, a careful characterization of numerous bacterial pathogens' responses to low shear forces is necessary to evaluate a more complete picture of how this physical stress impacts bacterial virulence since a “one-size-fits-all” response is clearly not the case.
登录
查看更多内容
影响因子：
5.1
作者：
Allen, Christopher A.;Niesel, David W.;Torres, Alfredo G.
通讯作者：
Torres, Alfredo G.
影响因子：
4.4
作者：
Fang, A;Pierson, DL;Demain, AL
通讯作者：
Demain, AL
影响因子：
4.2
作者：
Hammond, Timothy G.;Stodieck, Louis;Allen, Patricia L.
通讯作者：
Allen, Patricia L.
影响因子：
4.4
作者：
Kim, H. W.;Matin, A.;Rhee, M. S.
通讯作者：
Rhee, M. S.
影响因子：
5
作者：
Fang, A;Pierson, DL;Demain, AL
通讯作者：
Demain, AL