Colicin ia belongs to the family of bactericidal proteins , the channel - forming domain of which can form lethal ion channel in the membrane of escherichia coli and related strains such as shigella sonnei 大肠菌素ia是可形成离子通道的一种细菌素，其通道结构域( d451 ? i626 )能在同种异株的大肠杆菌内膜上形成致死性离子通道。
2.
However , the receptor and translocation domains of the colicin ia can only recognize the inner and outer membrane receptors of the escherichia coli , therefore the wild type colicin ia can not be developed into antibiotics against other types of bacteria 然而由于其信号识别结构域只能识别大肠杆菌外膜和内膜上的特异受体，因此野生型大肠菌素难以拓展成为对抗它种细菌的抗菌素。
3.
The fusion protein was bactericidal active against staphylococcus aureus . in present study , we will truncate the none channel - forming do main , then attach the agrd to the pore - forming region ( k544 - i626 ) to construct a new engineered multidqmain protein machine - compact engineered peptide targeting staphylococcus aureus . such engineered peptide was constructed by linking the gene of staphylococcal agrd pheromone with the gene of c - terminal ( 1626 ) of colicin la pore - forming region ( k544 - i626 ) with site - directed mutation 利用点突变方法将金黄色葡萄球菌信息素agrd ( i型， ystcdfim )的基因引入到大肠菌素fa梭基端1626基因上，并将限制性内切酶sacl酶切位点基因分别引入到大肠菌素fa的p4和k544上，通过酶切、胶回收、连接获得含大肠菌素ia水性孔道结构域和金黄色葡萄球菌信息素agrd基因的重组质粒。
4.
In the 1990s , the pheromones of gram - positive bacteria , which regulates the growth and toxin secretion of the same type bacteria , were identified they were peptides consisted by dozens of amino acids . the pheromones can auto - recognize membrane receptor of the identical types of bacteria . we had constructed a fusion protein named pheromonicin by introducing a staphylococcal pheromone agrd at the c - terminal of the colicin ia 丘小庆等利用信息素的自主导向特性和大肠菌素ia的致死性通道特性构建了由金黄色葡萄球菌信息素agrd和大肠菌素ia组成的融合蛋白，命名为pheromonicin ，该蛋白表现出了信息素和大肠菌素ia都不具有的抗金黄色葡萄球菌活性。
