Sensitivity of the LAMP assay Figure 1 presents sensitivity of the toxR-based LAMP assay when testing 10-fold serial dilutions of V. parahaemolyticus ATCC 27969 DNA templates. A representative optic graph and

corresponding melting curve analysis for the real-time PCR platform and a representative turbidity graph for the real-time turbidimeter platform are shown in Figure 1A-1C, respectively. On the real-time PCR platform, for templates ranging in concentration from 4.7 × 105 to 4.7 × 101 CFU per reaction tube, the average Ct values selleck kinase inhibitor of six repeats ranged from 17.35 to 40.72 min, with melting temperatures consistently falling at around 83°C. No amplification was obtained for the 4.7 CFU and 4.7 × 10-1 CFU templates. Therefore, the detection limit of the toxR-based LAMP assay run in a real-time PCR selleck machine was approximately 47 CFU per reaction. In the real-time turbidimeter platform, the average Tt values fell between 34.43 and 49.07 min for templates ranging from 4.7 × 105 to 4.7 × 102 CFU per reaction tube. In two out of six repeats, amplification of the 4.7 × 101 CFU template occurred (Figure 1C). Therefore, the

lower limit of detection for turbidity-based real-time LAMP assay was 47-470 CFU per reaction. Figure 1 Sensitivity of the LAMP ABT-888 clinical trial assay when detecting Vibrio parahaemolyticus ATCC 27969 in pure culture. (A) A representative optic graph generated using the real-time PCR machine; (B) Corresponding melting curve analysis for samples in (A); (C) A representative turbidity graph generated using the real-time turbidimeter. Samples 1-7 corerspond to serial 10-fold dilutions of V. parahaemolyticus ATCC 27969 cells ranging from 4.7 × 105 to 4.7 × 10-1 CFU/reaction; sample 8 is water. Clomifene The two PCR assays used to test the same set of V. parahaemolyticus ATCC 27969 templates by using F3/B3 and toxR-PCR primers had the same level of sensitivity, approximately 4.7 × 103 CFU per reaction tube (data not shown), i.e., up to 100-fold less sensitive than the toxR-based LAMP assay. Quantitative capability of LAMP for detecting V. parahaemolyticus in pure culture Figure 2 shows the standard curves generated

when detecting V. parahaemolyticus ATCC 27969 in pure culture based on six independent repeats in both real-time PCR machine (Figure 2A) and a real-time turbidimeter (Figure 2B). On the real-time PCR platform, the correlation coefficient (r 2) was calculated to be 0.95. When run in the real-time turbidimeter platform, the toxR-based LAMP assay had an r 2 value of 0.94. Figure 2 Standard curves generated when detecting Vibrio parahaemolyticus ATCC 27969 in pure culture. (A) Based on six independent repeats in a real-time PCR machine; (B) Based on six independent repeats in a real-time turbidimeter. Detection of V. parahaemolyticus cells in spiked oysters The sensitivity of detecting V. parahaemolyticus ATCC 27969 cells in spiked oyster samples is shown in Table 3.