摘要
艾滋病已给人类社会和经济带来了巨大影响。文章以HIV-1膜融合糖蛋白gp41的C端序列为参照,设计合成了C22多肽的基因序列,经PCR放大以后,通过pTMHa30-51质粒转导进E.coli BL21(DE3)中进行表达,纯化后得到了C22多肽,表达产物经SDS-PAGE电泳分析和质谱验证。结果表明:C22多肽具有很好热稳定性,良好的HIV-1入侵细胞抑制活性和水溶性,在实验浓度下对细胞无毒性。通过圆二色谱技术对C22的二级结构进行了检测,C22溶液在37℃条件下,α螺旋比例增加,而在80℃条件下,α螺旋比例则呈下降趋势。在不同pH值条件下,C22峰值变化较大,在向酸碱两性方向变化时,C22的α螺旋结构比例均相对有所减少,无规则卷曲增加,结构趋向松散。这也表明,在pH 6条件下,C22可以保持相对稳定的结构。该研究为此类多肽的光谱学性质研究和设计新的HIV-1治疗药物提供了理论基础。
Acquired immune deficiency syndrome (AIDS) is increasing its negative influences on human society and economy. In the present paper, HIV-1 cell fusion peptide inhibitor C22 was expressed and purified based on the C-terminal sequence of HIV- 1 membrane fusion glycoprotein gp41. The gene coding for C22 was totally synthesized using gp41 gene as a template and amplified by PCR. The cloned C22 gene was confirmed by restriction endonuclease and sequence analysis and then cloned into plasmid pTMHa30-51. The prepared plasmid was transformed into E. coli BL21 (DE3) and the expressing products were analyzed on SDS-PAGE and tested with mass spectrum. The results indicated that C22 showed high HIV-1 fusion inhibiting capacity, meanwhile, with good thermal stability and water-solubility, and showed no cell toxicity in tested concentrations. The spectral characteristics were tested with circular dichroism (CD). When treated at different temperature in solution condition, the content of a helix of C22 increased at 37 ℃ while decreased sharply at 80 ℃. The peak value changed significantly with different pH values. The content of a helix of C22 decreased as pH varied toward acid and alkali and the random coiling increased, which led to a relaxed structure. This result indicated that the C22 structure is stable with pH 6. This research may provide a theoretic foundation for the new type HIV-1 peptide inhibitor designing and spectral characteristics study.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2008年第8期1862-1865,共4页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(30570376)
上海市基础研究重点项目(06JC14068)资助