Identification and characteristics of temperature-sensitive sites of Pseudomonas plecoglossicida based on aptamers

Pseudomonas plecoglossicida can infect Pseudosciaena crocea and cause visceral white spot disease, resulting in substantial economic losses to the P. crocea industry. Pseudomonas plecoglossicida is a temperate-sensitive bacterium and only infects P. crocea below 22 ℃. Aptamers are oligonucleotide molecules selected by the systematic evolution of ligands by exponential enrichment (SELEX) and can identify all kinds of targets. In the present study, five aptamers (M17, M19, M48, M56 and M81) for P. plecoglossicida cultured at 18 ℃ were selected by SELEX and based on comparative analysis of the high frequency sequences. The five aptamers had significantly higher affinities for the pathogenic P. plecoglossicida at 18 ℃ than for the nonpathogenic P. plecoglossicida at 28 ℃ and the other six bacteria (Escherichia coli, Edwardsiella tarda, Aeromonas hydrophila, Vibiro harveryi, Vibiro alginolyticus, Pseudomonas aeruginosa) (P