Poster abstracts
Poster number 54 submitted by Nicolette Geron
Identification of DNA aptamer with modified nucleotide
Nicolette Geron (Department of Chemistry, Southern Illinois University Edwardsville), Sun-Jeong Im (Department of Chemistry, Southern Illinois University Edwardsville), Kamran Shavezipur (Department of Mechanical Engineering, Southern Illinois University Edwardsville), Mina Sumita (Department of Chemistry, Southern Illinois University Edwardsville)
Abstract:
Our main research interest is the development of a food safety biosensor that can detect foodborne pathogens by using DNA aptamers. The DNA aptamer that has a high affinity and specificity to the target pathogen is identified by a new SPR – SELEX, Surface Plasmon Resonance – Systematic Evolution of Ligands by EXponential enrichment, method. The target cells used are Excherichia Coli, K12. SPR-SELEX selects a deoxyuridine aptamer (dU-Ap) that utilizes deoxyuridine instead of thymidine as well as the other three common dNTPs. The 2’-H in deoxyribose gives DNA more chemical stability than the 2’-OH present in the RNA structure. However, RNA is able to form more conformations due to this structural difference with DNA. Therefore, the dU-Ap that are identified will have the stability of DNA and the structural variety of RNA providing for a broader selection of aptamers and a higher specificity when binding to E. coli. This project compares the sequences, stability, and structure of the two DNA aptamers: deoxythymidine aptamers (dT-Ap) and deoxyuridine aptamers (dU-Ap).
Keywords: SELEX, modification, SPR