In the determination of the project phase, we hope to create modern biotechnology achievements that can repair ancient murals.(This is because the ancient murals are the treasures of all human beings,and mural repair is also a more important and difficult part of cultural relics. Therefore, ) Our project is expeced to be applied to mural repair and imitation fields, combined with digital Dunhuang, biological 3D printing, etc. It will expand the likelihood of protecting cultural relics with synthetic biological methods.
In the next step immediately following our experiments, we plan to utilize bio-3d printing technology.Chao Zhong's group found that genetic engineering can not only change the composition and biochemical function of Bacillus subtilis biofilm, but also further regulate the mechanical (e.g. viscoelasticity) and physical and chemical properties (e.g. hydrophobicity) of the biofilm itself.[1] The modified biofilms exhibit gel-colloid properties that are more suitable for biofabrication and can be precisely fabricated into different 3D shapes by 3D printing. The principle of our project comes from Chao Zhong's team's research on E. coli biomineralized materials. So the complete application process of our project should look like this: The bacteria are mixed into a hydrogel that can be used for bio-3d printing (this hydrogel is similar in composition to M63 and can be used to induce expression) and coated on the wall.
Fig.1 Flow diagram
The projection technology is used to precisely control the range of blue light irradiation so that the strain in a specific area starts biofilm expression. After waiting for their biofilm to form, SBF was sprayed on them to make the strain start HA mineralization. The bacterium will die rapidly after the biofilm is fully mineralized, leaving the pattern stabilized.
At a later stage of application, we expect to obtain a complete database of mural holograms from Digital Dunhuang[2], another project that uses modern technology to restore murals.
Fig.2 What is "Digital Dunhuang"
The database will allow us to more accurately analyze the murals awaiting restoration and to perform larger, more precise restoration operations. At the same time, we can use a more advantageous lighting system, RGB[3], which is a more accurate system than the normal projection method and allows us to restore not only the field of frescoes, but also other artworks.
Fig.3 Color photography by Escherichia coli. Colored images (insets) were projected onto plates of bacteria containing the RGB system.
The above mentioned are some of the possibilities we have for project specific applications. While our project is currently achieved by laboratory characterization, we believe that the project has a wide range of applications including but not limited to the methods mentioned above. In the future, the practicality of the project can be further enhanced by improving the color fastness of the characterized products and reducing the environmental requirements of the characterization.
[1] Wang Y, An B, Xue B, et al. Living materials fabricated via gradient mineralization of light-inducible biofilms[J]. Nature Chemical Biology, 2021, 17(3): 351-359. [2] https://www.e-dunhuang.com [3] Fernandez-Rodriguez J, Moser F, Song M, et al. Engineering RGB color vision into Escherichia coli[J]. Nature chemical biology, 2017, 13(7): 706-708.
