藍藻蛋白(cyanophycin)，是一存在於藍藻菌中，作為能量，碳和氮來源的包涵體(inclusion body)。本實驗除了生產藍藻蛋白並分析組成，也對藍藻蛋白的物性做測定並嘗試將藍藻蛋白製成薄膜，並分析其成膜後的特性。
在使用基因重組的大腸桿菌生產藍藻蛋白的過程中，可藉由外加胺基酸來提高產率，產率會由1.3%~1.4% (w/w)提升至3.5%。再使用酸萃取法，溶出堆積在菌體中的藍藻蛋白。最後使用逆向高壓層析法分析其胺基酸組成。
經分析後，藍藻蛋白的胺基酸組成為精胺酸(arginine)：天冬門胺酸(aspartic acid)約為1：1，並含有極少量的離胺酸(lysine)。另外，藉由蛋白質電泳，可略估分子量約為24.4kDa~30kDa。
物性測定項目有微差掃瞄熱卡計分析(Differential Scanning Calorimeter)、傅立葉轉換紅外線光譜(Fourier Transform Infrared Spectrometer)分析以及熱重分析(Thermogravimetry Analysis)，經測定後可知藍藻蛋白的熔點約為194°C，且裂解溫度為246.9°C。且外加胺基酸並不影響藍藻蛋白的物性。
對於其成膜的物性，測量部份包含接觸角、減弱全反射兩部份。
發現以0.1N HCl作為溶劑的接觸角約為63°，而以0.1N HCl ：甲醇=1：1做為溶劑的接觸角為66°，且成膜後官能基不變。
另外，也試著使用外加不同莫爾比率的胺基酸來改變藍藻蛋白的組成，不過藉由DSC和蛋白質電泳分析來看，對藍藻蛋白的組成並沒有影響。

Cyanophycin is a water-insoluble reserve polymer of cyanobacteria, and is a product of nonribosomal peptide synthesis. We used recombinant Escherichia coli to produce cyanophycin, and extracted cyanophycin from the cells by the acid extraction method, and then analyzed its amino acids composition by high performance liquid chromatography.
In order to increase the cyanophycin yield, we supplemented additional amino acids in the medium when induction. After the addition of amino acids, the yield increased from 1.3~1.4% (w/w) to nearly 3.5% (w/w).
The results of high performance liquid chromatography analysis showed that the composition of amino acids is arginine : aspartic acid approximately 1 : 1, and the content of lysine is very low, almost undetectable.
Another aim of this study is to measure the physical properties of cyanophycin. We used differential scanning calorimeter, fourier transform infrared spectrometer and thermogravimetry analysis. We found the melting point of cyanophycin is approximately 196°C, and pyrolysis temperature is 246°C.
We also used cyanophycin to prepare membranes, and used fourier transform infrared spectrometer to analyze its function groups. We found that the spectra of the cyanophycin powder and membrane are almost the same. The contact angle of cyanophycin membrane prepared with 0.1N HCl is 63°, and the contact angle of cyanophycin membrane prepared with 0.1N HCl / methanol is 66°.
We also added amino acids in different ratios. The analysis of differential scanning calorimeter and sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that different ratios had no effect on the structure of chyanophycin.

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