大肠杆菌16S rRNA的核酶设计和初步应用

Design and Identification of Antisense Oligonucleotide Targeting to 16S rRNA of E.coli

针对细菌rRNA研发抑制细菌增殖的新型抗菌素是抗生素研究领域的新课题。细菌rRNA与基因mRNA一样自然形成折叠卷曲高级结构,其结构上可以结合反义核酸的位点即靶点,靶点的阐明是设计有效反义核酸、核酶(ribozyme)和脱氧核酶(DNAzyme)的关键。MAST方法固定16S rRNA,将其与寡核苷酸文库杂交筛选出靶点,获得了大肠杆菌16S rRNA的6个反义核酸结合靶点,并鉴定5个靶点有效,其中1个为高效。5个靶点的反义核酸能在通透性大肠杆菌菌株培养中不同程度地抑制其生长,针对高效靶点的核酶在转化大肠杆菌中表达而抑制其生长。

Targeting rRNA of bacteria is a new strategy for antibiotic agent development. The rRNA such as mRNA are naturally self-folded molecules which expose only limited accessible target-sites for binding. These accessible sites are pivotal for designing the effective antisense oligonucleotides, ribozymes, and DNAzymes. MAST, an RNA accessible site screening method, illustrated 6 accessible sites on 16S rRNA by immobilizing 16S rRNA and hybridizing with oligonucleotide library. 5 of the accessible sites were identified valid, and the antisense oligonucleotides targeted to which showed inhibition effectiveness on the proliferation. Among the 5 target sites, one showed the priority of accessibility. Ribozyme designed to this site showed obvious inhibition to the growth when induced expressing in the transfection E. coll.