Optimization detection of plant pathogenic bacteria by electrochemiluminescence polymerase chain reaction method

Plant pathogenic bacteria spread all over the world, causing a great deal of economic loss. This study has developed a novel method for rapid detection of plant pathogenic bacteria by electrochemiluminescence polymerase chain reaction (ECL-PCR) using two universal probes, a biotin-probe and a Ru(bpy)32+ (TBR)-probe. Biotin-probe sequence is complementary to the universal sequence of anti-sense primer, and TBR-probe sequence is the same as the universal sequence of sense primer. So the amplified PCR products can hybridize with TBR-probe and biotin-probe. After hybridizing, PCR products are captured by streptavidin coated magnetic bead through the biotin–streptavidin linkage, and then TBR reacts with tripropylamine to emit light for detection of plant pathogenic bacteria. This proposed method is applied to detect Fusarium oxysporum f. sp. Cubense and Xanthomonas oryzae pv. Oryzae. The results show that the method can successfully identify the plant pathogenic bacteria in the infected samples and these results are consistent with the results of gel electrophoresis. Importantly, this study can be used as an illustration for detecting various plant pathogenic bacteria and provides a feasible approach on developing ECL sensors to meet the demand of rapid detection of pathogenic bacteria, fungi, and viruses.