Rapid Visual Detection of Glaesserella parasuis with a Real-Time Recombinase-Aided Amplification Assay

Figure 3

Strategies of screening primers for G. parasuis RAA assay. (a) Schematic diagram of the primary primer screening. The positions of the five forward and five reverse candidate primers flanking the p1450-1497 probe are denoted by arrows. The name of the primer represents the oligonucleotide positions in the infB gene of Haemophilus parasuis SH0165 strain. (b) The application result of the real-time RAA in the primary screening for the best reverse primer. All the candidate reverse primers were screened with the randomly selected forward primer F1372-1403. (c) The application result of the real-time RAA in the primary screening for the best forward primer. All the forward candidate primers were screened with the reverse primer R1518-1549. (d) Schematic diagram of the secondary primer screening. (e) The application result of the real-time RAA in the secondary screening for the best reverse primer. The forward primer F1396-1427 was picked to screen all reverse candidate primers. (f) The application result of the real-time RAA in the secondary screening for the best forward primer. The reverse primer R1518-1549 was picked to screen all forward candidate primers. (g) Schematic diagram of the final primer screening. (h) The application result of the real-time RAA in the final screening for the best reverse primer. All seven candidate reverse primers were screened with the best selected forward primer F1395-1426. (i) The application result of the real-time RAA in the final screening for the best forward primer. All seven candidate forward primers were screened with the best selected reverse primer R1519-1549.

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