NI ²⁺ AND ZN ²⁺ -BINDING DNA MOTIFS REVEALED IN DNA APTAMERS TO AFRICAN SWINE FEVER VIRUS

Rapid and specific diagnosis of viral and bacterial infections is a significant challenge in medicine and veterinary science, especially in the case of epidemically dangerous pathogens. The African swine fever virus (ASFV), for example, causes annual outbreaks among livestock, resulting in significant economic losses for farmers. DNA aptamers have been identified as a promising tool for point-of-care diagnostics, being highly specific to the target and stable ambient temperatures during storage. In this study, we describe the selection of DNA aptamers targeting the p54 viral protein using a single-round selection process. These aptamers were able to bind both to recombinant protein and inactivated ASFV viral particles. Analysis of the newly generated aptamers revealed a dependence of affinity and thermal stability on Ni ²⁺ content, which was a dopant in the selection process. In some cases, the affinity increased 100 times, and melting temperature increased by 30°C. We have identify two novel DNA motifs that bound 2-3 Ni ²⁺ or Zn ²⁺ ions.