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Biology subjects

Nechaev, A.

Publications and source records attributed to Nechaev, A..

2 recordsLinked to original sources

NI2+ AND ZN2+-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 Ni2+ content, which was a dopant in the selection process. In some cases, the affinity increased 100 times, and melting temperature increased by 30{degrees}C. We have identify two novel DNA motifs that bound 2-3 Ni2+ or Zn2+ ions.

synthetic biology↗

Surface-enhanced Raman spectroscopy on the membranes for antimicrobial resistance testing

Antimicrobial resistance is one of the top global health threats; it is associated with millions of deaths per year. Traditional and most commonly used antibiotic susceptibility tests are based on detection of bacterial growth and its inhibition in the presence of an antimicrobial. These tests typically take over 1-2 days to perform, so empirical therapy schemes are often administered before the proper testing. Rapid tests for antimicrobial resistance are necessary to optimize the treatment of bacterial infection. A combination of MTT test with Raman spectroscopy to provide 1.5-hour long test antimicrobial susceptibility determination requiring 106-108 CFU/mL of bacteria. Here the first rapid antibiotic susceptibility test for trace amounts of bacteria is described. The bacterial titer can be decreased down to 102 CFU/mL using surface-enhanced Raman spectroscopy (SERS) of the MTT-treated bacteria caught with the silver coated track-etched membranes allowing the antimicrobial testing of low-titer bacterial samples within 1.5 hour. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=109 SRC="FIGDIR/small/664554v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@1e241c5org.highwire.dtl.DTLVardef@14c071forg.highwire.dtl.DTLVardef@67aad7org.highwire.dtl.DTLVardef@140db_HPS_FORMAT_FIGEXP M_FIG C_FIG A combination of MTT test with membrane filtration and surface-enhanced Raman spectroscopy is used to determine antibiotic susceptibility of E.col

microbiology↗