Use of an AMCA-modified specific DNA aptamer for rapid detection of Vibrio vulnificus

Abstract

Abstract Vibrio vulnificus (V.V) can cause serious infections in humans. The traditional method to culture this pathogen is time-consuming and has a high failure rate. Common pathogenic microorganisms present in the seawater of the Fujian Sea area were collected, cultured, and identified. The samples were found to contain mainly Staphylococcus aureus (S.A), Escherichia coli (E. Coli), Pseudomonas aeruginosa (P.A), V.V, Vibrio alginolyticus (V.A), Vibrio parahaemolyticus (V.P). A DNA aptamer was constructed with an aminomethylcoumarin acetate (AMCA) modification on the 5’ ends, to target V.V and generate a fluorescent signal upon contact. Using this custom aptamer, we were able to detect the presence of V.V through fluorescence microscopy. Based on the pathogenic microorganisms we identified in our samples, the aptamer was screened and optimized for rapid detection of V.V infections. We used modified aptamers to detect V.V from 50 bacteria. In this experiment, the sensitivity, specificity, positive predictive value and negative predictive value of the modified aptamer to detect V.V were 100%[95%CI(0.39,1)], 93.4%[95%CI(0.81,0.98)], 57%[95%CI(0.20,0.88), 100%[95%CI(0.89,1) respectively. We are able to rapidly detect V.V specimens via a fluorescence reaction within 30 minutes. Our results showed that this modified DNA aptamer have potential diagnosis of V.V infection. We need more research to explore the application of aptamers in pathogen infection.