Team:WHU-China/Description




Description



After we got the inspiration from the‘plain gauze garment (素纱襌衣)’, we chose those fragile silk relics as our restoration objects, and designed our project into three parts: Reinforcement, Converter and functionalization.



Reinforcement



From the trip to Jingzhou Conservation and Restoration Center, we got that many experts had made a certain amount of exploration on using BC (Bacteria Cellulose) to reinforce the silk relics. For BC had many advantages, we chose BC as the reinforcement material. On the basic of their previous work, we designed to apply synthetic biology for a better preservation of silk relics!





From the visit to Chinese Silk Museum in Hangzhou, we learned that the actual condition in tomb is very complex, the unearthed silk relics always have all kinds of complication, thus, the weak area on them will always be of irregular shape.


To achieve the irregular reinforcement by adding BC onto the different shapes and various degrees of fragile areas, which can fit better in factual application, we designed a light system. It can control the secretion of BC by exposing the bacteria to light with certain wavelength. Combined with a hardware we designed, the light system can realize the irregular reinforcement well.






Converter



We designed a converter to assemble our functional peptide onto the Bacteria cellulose by two stratums of linkages.


Firstly, a CBD (Cellulose Binding Domain) is used to bind with bacteria cellulose via its natural affinity. Secondly, the free side of CBD will be streptomycinated and it will combine with the functional peptides with biotin.


The streptavidin (SA) is a protein secreted by Streptomyces avidinii with a molecular weight of 65kD. The molecule consists of four identical peptide chains, each of which binds to a biotin. With this kind of biotin-avidin system, the peptides and BC can achieve a tightly linkage.





Adding biotin is usually much easier than expressing a fused protein of CBD and functional short peptides, we hope to realize a platform to create more functional possibility via this converter in the future.



Functionalization



According to the common problems in the preservation of silk relics, we decided to produce AMPs (Antimicrobial peptides) to defense the molds taint after our BC reinforcement and AOPs (Antioxidant peptides) to scavenge free radicals that may cause aging of the silk relics caused by illumination during the exhibition.





The AMPs we selected are specially against filamentous fungi that are associated with altering of the permeability of the fungal membranes. We hope it can defense Aspergillus and Penicillium that usually contaminate the silk relics.


As for the AOPs, we use a designed AOP called DSAOP, which is modified to fit an efficient production in E.coli by increasing its stability and solubility, at the same time keeping its strong ability of scavenging free radicals as the natural ones.









Reference



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  3. Pere Picart et al. Identification of defensin-encoding genes of Picea glauca: characterization of PgD5, a conserved spruce defensin with strong antifungal activity. BMC Plant Biol. 2012; 12: 180.

  4. Yanyan Wu et al.Preparation and Antioxidant Activities In Vitro of a Designed Antioxidant Peptide from Pinctada fucata by Recombinant Escherichia coli. J. Microbiol. Biotechnol. (2018), 28(1), 1–11.

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