Establishment of loop-mediated isothermal amplification method for detection of Legionella pneumophila

Abstract

To establish a simple and rapid molecular detection for Legionella pneumophila. The loop-mediated isothermal amplification (LAMP) was applied for detection of Legionella pneumophila. A set of primers were designed to identify six special areas in mip gene of Legionella pneumophila. Genomic DNAs from 13 bacterial strains,including 8 Legionella pneumophila strains and 5 other bacterial strains were amplified by LAMP and general PCR method to evaluate the specificity and sensibility of LAMP. All positive tubes produced visible white precipitation, and no precipitation was observed in others. By adding smart green fluorescent dye, all Legionella pneumophila positive tubes presented a strong green fluorescence, while others showed weak fluorescence. The detection rate of LAMP was higher than that of general PCR. The detection limits were 576fg with genomic DNA of Legionella pneumophila,and 8 cfu/mL with positive water samples. LAMP detection of Legionella pneumophila is an effective and low-cost method with high specificity and sensitivity requiring no special equipment.