Title Application of Multilocus Sequence Analysis (MLSA) for Accurate Identification of Legionella spp. Isolated from Municipal Fountains in Chengdu, China, Based on 16S rRNA, mip, and rpoB Genes
Author Wang Guan1, Ying Xu1,2, Da-li Chen1, Jia-nan Xu1, Yu Tian1, and Jian-ping Chen1,3*
Address 1Department of Parasitology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, Sichuan, P. R. China, 2Department of Clinical Laboratories, the First Affiliated Hospital of Chengdu Medical College, Chengdu, 610500, Sichuan, P. R. China, 3Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, Sichuan University, Chengdu 610064, Sichuan, P. R. China
Bibliography Journal of Microbiology, 50(1),127-136, 2012,
DOI
Key Words Legionella, MLSA, 16S rRNA, mip, rpoB, municipal fountain
Abstract Legionellosis (Legionnaires’ disease; LD) is a form of severe pneumonia caused by species of Legionella bacteria. Because inhalation of Legionella-contaminated aerosol is considered the major infection route, routine assessments of potential infection sources such as hot water systems, air-conditioner cooling water, and municipal fountains are of great importance. In this study, we utilized in vitro culture and multilocus sequence analysis (MLSA) targeting 16S rRNA, mip, rpoB, and mip-rpoB concatenation to isolate and identify Legionella spp. from 5 municipal fountains in Chengdu City, Sichuan Province, China. Our results demonstrated that 16S rRNA was useful for initial identification, as it could recognize isolates robustly at the genus level, while the genes mip, rpoB, and mip-rpoB concatenation could confidently discriminate Legionella species. Notably, the three subspecies of L. pneumophila could be distinguished by the analysis based on rpoB. The serotyping result of strain CD-1 was consistent with genetic analysis based on the concatenation of mip and rpoB. Despite regular maintenance and sanitizing methods, 4 of the 5 municipal fountains investigated in this study were positive for Legionella contamination. Thus, regularly scheduled monitoring of municipal fountains is urgently needed as well as vigilant disinfection. Although the application of MLSA for inspection of potential sites of infection in public areas is not standard procedure, further investigations may prove its usefulness.