Williams R W
J Biol Chem. 1985 Apr 10;260(7):3937-40.
Raman spectra were taken of human alpha (leukocyte) interferon subtype A (HuIFN-alpha A) purified from extracts of transformed Escherichia coli. Quantitative analysis of the conformationally sensitive amide I band indicates that IFN (interferon)-alpha A is 75 +/- 5% helical and 7 +/- 4% beta-strand. An independent analysis of the amide III spectrum indicates 71 +/- 5% helix and 10 +/- 6% beta-strand. These results differ with a recently proposed three-dimensional model based on secondary structure predictions derived from sequence and with circular dichroism measurements. The Raman spectrum of IFN-alpha A is compared with the spectra of several other helical proteins: hemerythrin, intestinal calcium-binding protein, melittin, and insulin.
对从转化的大肠杆菌提取物中纯化得到的人α（白细胞）干扰素A亚型（HuIFN-αA）进行了拉曼光谱测定。对构象敏感的酰胺I带的定量分析表明，IFN（干扰素）-αA为75±5%的螺旋结构和7±4%的β-折叠结构。对酰胺III光谱的独立分析表明，其螺旋结构为71±5%，β-折叠结构为10±6%。这些结果与最近基于从序列推导的二级结构预测以及圆二色性测量所提出的三维模型不同。将IFN-αA的拉曼光谱与其他几种螺旋蛋白的光谱进行了比较：血蓝蛋白、肠钙结合蛋白、蜂毒肽和胰岛素。
