Jump to Main Content
Rapid and sensitive detection of Pseudomonas aeruginosa in chlorinated water and aerosols targeting gyrB gene using realâtime PCR
- Lee, C.S., Wetzel, K., Buckley, T., Wozniak, D., Lee, J.
- Journal of applied microbiology 2011 v.111 no.4 pp. 893-903
- DNA, DNA primers, Legionella pneumophila, Pseudomonas aeruginosa, aerosols, airborne transmission, bacteria, burden of disease, chlorine, cystic fibrosis, detection limit, drinking water, filters, gelatin, genes, neutralization, patients, quantitative polymerase chain reaction, risk assessment
- Aims: For the rapid detection of Pseudomonas aeruginosa from chlorinated water and aerosols, gyrB geneâbased realâtime PCR assay was developed and investigated. Methods and Results: Two novel primer sets (pa722F/746MGB/899R and pa722F/746MGB/788R) were designed using the most updated 611 Pseudomonas and 748 other bacterial gyrB genes for achieving high specificity. Their specificity showed 100% accuracy when tested with various strains including clinical isolates from cystic fibrosis patients. The assay was tested with Ps. aeruginosaâcontaining chlorinated water and aerosols to simulate the waterborne and airborne transmission routes (detection limit 3Â·3âÃâ102âCFUâperâPCRâ2Â·3âÃâ103âCFUâperâPCR). No chlorine interference in realâtime PCR was observed at drinking water level (c.â1âmgâlâ1), but high level of chorine (12âmgâlâ1) interfered the assay, and thus neutralization was needed. Pseudomonas aeruginosa in aerosol was successfully detected after capturing with gelatin filters with minimum 2âmin of sampling time when the initial concentration of 104âCFUâmlâ1 bacteria existed in the nebulizer. Conclusions: A highly specific and rapid assay (2â3âh) was developed by targeting gyrB gene for the detection of Ps.Â aeruginosa in chlorinated water and aerosols, combined with optimized sample collection methods and sample processing, so the direct DNA extraction from either water or aerosol was possible while achieving the desired sensitivity of the method. Significance and Impact of the Study: The new assay can provide timely and accurate risk assessment to prevent Ps.Â aeruginosa exposure from water and aerosol, resulting in reduced disease burden, especially among immuneâcompromised and susceptible individuals. This approach can be easily utilized as a platform technology for the detection of other types of microâorganisms, especially for those that are transmitted via water and aerosol routes, such as Legionella pneumophila.