铜绿假单胞菌形成称为生物膜的聚集体。以前的研究表明,当铜绿假单胞菌在太空种植时,比地球上生长的生物膜更厚和结构不同的生物膜。我们研究了微重力,在实验室环境中模拟,影响了增长,殖民,铜绿假单胞菌PA14野生型菌株的毒力潜力,以及在关键的生物膜形成步骤中改变的两个表面附着缺陷(悲伤)突变体:flgK和pelA。使用高纵横比旋转壁容器(HARV)生物反应器,铜绿假单胞菌在长时间(6天)暴露于模拟微重力或正常重力条件下生长至静止期。曝光后,测量培养物形成生物膜的能力。此外,提取和定量在孵育期间由每种培养物形成的色素(绿脓苷)。我们证明,首次长时间暴露于低剪切模型微重力(LSMMG)和没有营养补充会显着降低暴露后野生型铜绿假单胞菌PA14生物膜的形成能力和暴露过程中的卵蓝蛋白的产生,而突变菌株对这两种特性表现出不同的结果。
目标:考虑到人类进行长时间太空旅行的计划,我们研究了微重力培养时铜绿假单胞菌中生物膜和色素/毒力因子的形成。这些细菌是免疫受损个体中的机会病原体。以前对太空旅行者的研究表明,免疫系统会减少。因此,我们的研究揭示了在模拟微重力条件下长时间培养细菌如何影响其生长特性。
Pseudomonas aeruginosa forms aggregates known as biofilms. Previous studies have shown that when P. aeruginosa is cultivated in space, thicker and structurally different biofilms are formed than from those grown on Earth. We investigated how
microgravity, simulated in a laboratory setting, influenced the growth, colonization, and virulence potentials of a P. aeruginosa PA14 wild-type strain, as well as two surface attachment-defective (sad) mutants altered at crucial biofilm-forming steps: flgK and pelA. Using high-aspect ratio rotating-wall vessel (HARV) bioreactors, P. aeruginosa bacteria were grown to stationary phase under prolonged (6 days) exposure to simulated
microgravity or normal gravity conditions. After the exposure, the capacity of the culture to form biofilms was measured. Additionally, pigment (pyocyanin) formed by each culture during the incubation was extracted and quantified. We demonstrate that the first prolonged exposure to low-shear modeled
microgravity (LSMMG) and without nutrient replenishment significantly diminishes wild-type P. aeruginosa PA14 biofilm formation abilities after exposure and pyocyanin production during exposure, while the mutant strains exhibit differing outcomes for both properties.
OBJECTIVE: Given plans for humans to engage in prolonged space travel, we investigated biofilm and pigment/virulence factor formation in Pseudomonas aeruginosa when cultivated in
microgravity. These bacteria are opportunistic pathogens in immunocompromised individuals. Previous studies of space travelers have shown some immune system diminutions. Hence, our studies shed some light on how prolonged cultivation of bacteria in simulated
microgravity conditions affect their growth characteristics.