Recently, the international academic journal mSystems published an article entitled " A deep sea bacterium senses blue light via a BLUF dependent pathway ", reporting that the research group of Sun Chaomin's group from the Key Laboratory of Experimental Marine Biology of the Chinese Academy of Sciences has reported on the deep-sea cold spring non-photosynthetic bacteria through blue light.
The research results that sensory proteins sense blue light and stimulate energy synthesis provide another example for deep-sea microorganisms to sense and utilize light energy
As we all know, the growth of all things depends on the sun, and a large number of studies have also confirmed that the growth of the true photosphere organisms will be more or less affected by light
But for deep-sea habitats, researchers have long thought of it as a dark, chemically-powered ecosystem
But there is growing evidence that different forms of geoluminescence or bioluminescence exist not only in deep-sea hydrothermal areas, but also in other deep-sea habitats such as cold springs
Studies have shown that nearly 80% of deep-sea animals can emit light, mainly in the form of blue light
Many microbiologists have also been exploring whether deep-sea microbes can sense and even use blue light or other wavelengths of light
However, due to the difficulty of deep-sea sample collection and the difficulty of culturing deep-sea microorganisms, the above problems have not been effectively solved
Focusing on the above scientific issues, Sun Chaomin's research team obtained a strain of Spongebacterium from the sediment samples using the blue-light enrichment culture technology based on the sediment collected by the "Science" ship in 2017
near a cold spring vent in the deep-sea waters of the South China Sea .
The study found that compared to other types of light, the strain obtained the fastest growth rate under the irradiation of blue light ( 470 nm
However, genome sequencing showed that the strain did not contain the chlorophyll synthesis pathway and the rhodopsin-encoding gene, and did not belong to the common type of light energy utilization
The proteomic results showed that the bacterial blue light sensing protein BLUF plays an important role in the process of sensing blue light.
The researchers knocked out the gene encoding BLUF by molecular genetics and found that the ability of the bacteria to sense blue light was significantly weakened, which further verified.
The results of the proteome; consistent with the results of the in vivo experiments, the blue light protein expressed in vitro also showed obvious blue light sensing activity
The above proteomic, genetic and biochemical experimental results have comprehensively confirmed that the blue light sensing protein BLUF mediates the blue light perception of deep-sea bacteria, and further activates the synthesis pathway of acetyl-CoA , thereby significantly enhancing the tricarboxylic acid cycle pathway and Energy production, which ultimately promotes the rapid growth of the strain
It is worth noting that the homologous protein of the blue light receptor BLUF is widely distributed in deep-sea microorganisms, indicating that many microorganisms from deep-sea sources can also sense and utilize blue light through a similar pathway, which also suggests that microbiologists need to consider microorganisms in future research.
Contribution of mediated light energy metabolism to energy cycling in deep-sea ecosystems
Proteomic methods reveal that BLUF is a key factor in deep-sea bacteria sensing blue light and activating energy synthesis
Genetic methods confirm that BLUF is a key factor in deep-sea bacteria sensing blue light and activating energy synthesis
In vitro expression method confirms that BLUF has the activity of sensing blue light
BLUF mediates deep-sea bacteria sensing blue light and activating energy synthesis pathway
Shan Yeqi, a doctoral student in the Key Laboratory of Experimental Marine Biology, is the first author, and researcher Sun Chaomin is the corresponding author
The research was jointly funded by the Strategic Pilot Science and Technology Project of the Chinese Academy of Sciences and the Frontier Key Deployment of the Ocean Science Center of the Chinese Academy of Sciences
Yeqi Shan, Ge Liu, Ruining Cai, Rui Liu, Rikuan Zheng, Chaomin Sun * .
A deep-sea bacterium senses blue light via a BLUF-dependent pathway.
mSystems , 2022, 7(1): e01279-21.
Link to the paper: https://journals.