What is smURFP？The new class of fluorescent protein was developed from an allophycocyanin α-subunit (APCα). Native APC requires a lyase to incorporate phycocyanobilin. The evolved FP, engineered by Roger Tsien, named small Ultra-Red FP (smURFP), covalently attaches biliverdin (BV) without a lyase, and has appropriate excitation/ emission peaks, a large extinction coefficient and quantum yield, and comparable photostability to eGFP. What we have done is to make full use of this fluorescent protein as an essential element of our system.
What’s the advantages of smURFP?smURFP has 642/670 nm excitation/ emission peaks，which means it has advantageous fluorescent intensity, minimize light scattering and absorbance by endogenous biomolecules, which reduces auto fluorescence. Also, it uses endogenous chromophores to eliminate O2 necessity and H2O2 production. As what we expected, it can be applied in anaerobic environment, which means that it can be applied to the intestine. What’s more, nontoxic.
Why have we analyzed smURFP’s structure?To find suitable site to perform mutation in order to continue the research of Roger Tsien that has not yet completed, to continue a study which has lasted for ten years by a great scientist of our nation. It can also help other scientists to work on this protein.
What can smURFP do for birds’ health?smURFP can connected with biliverdin and fluoresce which has really good transmission. Therefor we can use this protein to detect biliverdin content. Actually it’s really important for birds,reptiles and egg coloration studies. Birds and reptiles have little biliverdin reeducates activity and produce very low amounts of bilirubin. Increased concentrations of biliverdin in serum, bile, or excreta can point to anemia, liver problems and biliary obstruction. Biliverdin is also an important pigment of eddshells in several species. Egg coloration studied also require a biliverdin assay to determine biliverdin content in eggshells.
Why have we tried to detect Intestinal bacteria?The number of microbes is 10 times larger than that of human cells. Only in our gut, there are more than 100 trillion bacteria, which help the body digest food, produce vitamins to prevent diseases caused by bacteria in the food and stimulate the immune system.
Why have we chose smURFP to create a Real-time fluorescence detection system?At present, the fluorescence system is unable to monitor intestinal bacteria in vivo because of the limitation of wavelength of the fluorescent protein. And we use smURFP as our tool for tracking them. We have constructed surface display system and co-expression system for our goal. The results shows that our idea is feasible and excellent.