The Drug-resistance Gene Decetion And Molecular Typing Of Stenotrophomonas Maltophilia

ObjectiveA Rapid detection of L1,L2type beta lactamase was to establish. Analysingthe Stenotrophomonas maltophilia by MLST and PCR, which provided the basisof the clinical treatment.MethodsA loop-mediated isothermal amplification (LAMP) assay was developed andvalidated for the specific detection of L1, L2type beta lactamase gene bydesigning5pairs of primers which distinguish8special L1, L2sequences inStenotrophomonas maltophilia which is Carbapenem resistant.The process ofthe LAMP reaction will produce a white precipitate of magnesiumpyrophosphate, which can be detected by monitoring turbidity to determinethereaction result. Real time turbidity metermonitoring the reaction resultsshowed that two methods including monitoring turbidity and adding Calceinbefore reaction were used to determine the negative and positive results.Using PCR method for the detection of7housekeeping genes of18Stenotrophomonas maltophilia strains, analyse the results by comparing withthe online data, then making the molecular typing analyse.ResultsThe LAMP method was set up for the detection of L1, L2gene ofStenotrophomonas maltophilia. LAMP method has good specificity and thesensitivity of LAMP with detection limits is100times than that of PCR which hasthe disadvantages of long time, complex procedures and strict requirements of the samples. So the LAMP method is more suitable for the rapid detection of L1,L2type beta lactamase gene. The MLST results shows that3strains have thesame ST number25,4strains are ST4,2strains are ST8,5strains are ST31,3strains are ST29,2strains are ST28. ST23and ST24are new typing strains.ConclusionsThe LAMP process is simple, the experimental device is easy, the reactionresults discernible, high sensitivity and specificity.it is suitable for hospitalinfection and Rapid detection of L1, L2beta lactamase gene. MLST is the newmethod for the molecular typing of Stenotrophomonas maltophilia, provide thebasis for the epidemiological research of Stenotrophomonas maltophilia.