Bao Xu-Chong, Tang Hong-Zhi, Li Xue-Gong, Li An-Qi, Qi Xiao-Qing, Li Deng-Hui, Liu Shan-Shan, Wu Long-Fei, Zhang Wei-Jia
Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China.
University of Chinese Academy of Sciences, Beijing 101408, China.
Microorganisms. 2023 May 23;11(6):1362. doi: 10.3390/microorganisms11061362.
Bioluminescence is a common phenomenon in nature, especially in the deep ocean. The physiological role of bacterial bioluminescence involves protection against oxidative and UV stresses. Yet, it remains unclear if bioluminescence contributes to deep-sea bacterial adaptation to high hydrostatic pressure (HHP). In this study, we constructed a non-luminescent mutant of Δ and its complementary strain c-Δ of ANT-2200, a deep-sea piezophilic bioluminescent bacterium. The wild-type strain, mutant and complementary strain were compared from aspects of pressure tolerance, intracellular reactive oxygen species (ROS) level and expression of ROS-scavenging enzymes. The results showed that, despite similar growth profiles, HHP induced the accumulation of intracellular ROS and up-regulated the expression of ROS-scavenging enzymes such as , and , specifically in the non-luminescent mutant. Collectively, our results suggested that bioluminescence functions as the primary antioxidant system in strain ANT-2200, in addition to the well-known ROS-scavenging enzymes. Bioluminescence contributes to bacterial adaptation to the deep-sea environment by coping with oxidative stress generated from HHP. These results further expanded our understanding of the physiological significance of bioluminescence as well as a novel strategy for microbial adaptation to a deep-sea environment.
生物发光是自然界中的一种常见现象，尤其是在深海中。细菌生物发光的生理作用包括抵御氧化应激和紫外线应激。然而，生物发光是否有助于深海细菌适应高静水压（HHP）仍不清楚。在本研究中，我们构建了深海嗜压发光细菌ANT-2200的非发光突变体Δ及其互补菌株c-Δ。从耐压性、细胞内活性氧（ROS）水平和ROS清除酶的表达等方面对野生型菌株、突变体和互补菌株进行了比较。结果表明，尽管生长曲线相似，但HHP诱导了细胞内ROS的积累，并上调了如 、 和 等ROS清除酶的表达，特别是在非发光突变体中。总的来说，我们的结果表明，除了众所周知的ROS清除酶外，生物发光在菌株ANT-2200中作为主要的抗氧化系统发挥作用。生物发光通过应对HHP产生的氧化应激，有助于细菌适应深海环境。这些结果进一步扩展了我们对生物发光生理意义的理解，以及微生物适应深海环境的新策略。
