Orruño Maite, Parada Claudia, Kaberdin Vladimir R, Arana Inés
Department of Immunology, Microbiology and Parasitology, Faculty of Science and Technology, University of the Basque Country UPV/EHU, 48340 Leioa, Spain.
Research Centre for Experimental Marine Biology and Biotechnology (PIE-UPV/EHU), 48620 Plentzia, Spain.
Microorganisms. 2021 Mar 13;9(3):594. doi: 10.3390/microorganisms9030594.
A number of spp. belong to the well-studied model organisms used to understand the strategies developed by marine bacteria to cope with adverse conditions (starvation, suboptimal temperature, solar radiation, etc.) in their natural environments. Temperature and nutrient availability are considered to be the key factors that influence physiology, morphology, and persistence in aquatic systems. In contrast to the well-studied effects of temperature and starvation on survival, little is known about the impact of visible light able to cause photooxidative stress. Here we employ ATCC 14126 as a model organism to analyze and compare the survival patterns and changes in the protein composition of its cell envelope during the long-term permanence of this bacterium in seawater microcosm at 20 °C in the presence and absence of illumination with visible light. We found that exposure to visible light reduces cell culturability likely inducing the entry into the Viable but Non Culturable state (VBNC), whereas populations maintained in darkness remained culturable for at least 21 days. Despite these differences, the starved cells in both populations underwent morphological changes by reducing their size. Moreover, further proteomic analysis revealed a number of changes in the composition of cell envelope potentially accountable for the different adaptation pattern manifested in the absence and presence of visible light.
一些物种属于经过充分研究的模式生物，用于了解海洋细菌在其自然环境中应对不利条件（饥饿、温度不适宜、太阳辐射等）所采用的策略。温度和养分可用性被认为是影响水生系统中细菌生理、形态和存活能力的关键因素。与对温度和饥饿对细菌存活影响的深入研究相比，关于可见光导致光氧化应激的影响知之甚少。在这里，我们以ATCC 14126作为模式生物，分析并比较该细菌在20°C的海水微宇宙中，在有可见光照射和无可见光照射的情况下长期存在期间的存活模式及其细胞包膜蛋白质组成的变化。我们发现，暴露于可见光会降低细胞的可培养性，可能导致其进入活的但不可培养状态（VBNC），而处于黑暗中的菌群至少21天内仍可培养。尽管存在这些差异，但两个菌群中的饥饿细胞都通过缩小尺寸发生了形态变化。此外，进一步的蛋白质组学分析揭示了细胞包膜组成的一些变化，这些变化可能是在有无可见光情况下表现出的不同适应模式的原因。
