大腹园蛛黏液蛋白ASG2 C端功能模块的克隆表达及圆二色谱分析

Cloning,expression and CD spectra of the C-terminal domain of aggregate sticky glue 2 from Araneus Ventricosus

蜘蛛分泌的黏合物(ASG),可形成黏附性极佳的胶滴,可用于捕获猎物。其中ASG2组分被证明属于蛛丝蛋白家族,因其独特的材料学性能,ASG2具有作为新型生物材料的潜能。目前,有关ASG2末端功能区(CT)的研究非常少,阻碍了ASG2的仿生应用。为丰富ASG2 CT的基因材料,以大腹园蛛基因组DNA为模板,利用锚定PCR的方法,首次获取了大腹园蛛ASG2 CT的完整编码基因AvASG2CT,并对其进行了外源克隆表达及纯化,产量可达75 mg/L;同时利用圆二色谱对其二级结构进行分析,表明其主要构象为α-helix,这是首次对ASG2 CT的二级结构进行探索,为后续的ASG2 CT的结构和功能研究奠定基础。

The aggregate sticky glue(ASG)secreted by spider can form into very sticky droplets using for prey capture.As one component of ASG,ASG2 has been proved is a spidroin,which has the potential as a new type biomaterial for its unique material properties.At present,there are few researches about the C-terminal domain(CT)of the ASG2 which restricts the use of the ASG2.The sequence(AvAGS2CT)of the C-terminal domain of the ASG2 from Araneus ventricosus was firstly obtained via the single primer PCR based on the genomic DNA.And the AvAGS2CT was further cloned,expressed and purified with the finally yield of 75 mg/L;meanwhile,at the first time,the secondary structure of the AvAGS2CT protein was analyzed by the CD spectra,which indicated that theα-helix is its predominant secondary structure.These results provide useful information for the CT structural and functional analysis of ASG2.