The Detection Of Animal Origin Salmonella Resistance Genes And Pathogenicity Island Genes Of MgtC And SopB

Salmonella is an important pathogen that can cause human and animal diseases. The epidemiological survey demonstrates that Salmonella pathogenicity islands are associated with human salmonellosis diseases. Virulence associated genes were found that have much effect on control and prevention of the disease for further understanding the development of bacterial diseases.PCR (Polymerase Chain Reation) served as basic technique in this paper which primer sequences were based on specific gene sequences of drug resistance gene and pathogenicity island gene in pathogenic Salmonella. After optimizing the PCR reaction condition the PCR detection method of drug resistance gene and duplex PCR method of drug resistance gene. Epidemiological investigations of Salmonella in pigs were setted up which aims to provide sufficient theoretical basis for zoonotic salmonellosis control and prevention.Detailed research methodology and findings of the study are as follows:1、TheAnimal origin Salmonella resistance genes detection by PCRDrug sensitive test in Salmonella were carried out of24strains conserved in our laboratory. Six primers were designed for drug resistance gene in aminoglycosides, tetracyclines, beta-lactam and chloramphenicol. After contrast, the ratio of more than two kinds of antibacterial agents is83.3%, while contain two antibacterial agents is25%, four is35%, five is25%and seven and eight is10%and5%. It illustrates that the amplification ratio in tetA and tetB is in accordance with drug sensitive test of tetracyclines, while the aac(3)-Ⅰand aph(3)-Ⅱ are in agree with the experiment results of gentamicin, streptomycin, neomycin. However, the catI gene is non-significant with florfenicol and chloramphenicol results.2、The Animal origin Salmonella pathogenicity island gene PCR detectionSalmonella pathogenicity island genes were studied based on the sequence in GenBank. Two primers were designed for pathogenicity island genes mgtC and sopB. The gene of Salmonella (ATCC9150) was setted as template, after optimizing the PCR reaction condition, the duplex PCR detection method for Salmonella was established. The specificity experiment demonstrates that two fragments with500bp and1000bp can be amplified. The limite of detection is10CFU/mL.3、Salmonella pathogenicity island double PCR method for detection applications The double PCR method was used for9strains Salmonella, which separed from pigs. The result shows that there are8strains contain mgtC genes based on this detection method, the ratio is88.9%.So as to the sopB gene. The detection results also proved that this method which has established is feasible and provide effective protection for rapid diagnosis of Salmonella and molecular Epidemiological surveys.This paper showed that Salmonella PCR assay for detection of resistance genes and the duplex PCR method for pathogenicity island detection have been successfully established. The Salmonella resistance gene and drug resistance were compared which showed that the detection rate and susceptibility test results of animal-borne Salmonella isolates resistant gene are basically the same. Moreover, the established double PCR method of Salmonella pathogenicity island method has low density and high detection specificity which can detect Salmonella rapidly and provide theoretical guidance for zoonotic salmonellosis.