Genomic characterization of Legionella pneumophila isolated from industrial circulating cooling water
10.20001/j.issn.2095-2619.20260208
- VernacularTitle:工业循环冷却水来源的嗜肺军团菌基因组学特征分析
- Author:
Man YU
1
;
Ying TANG
;
Xiangjun ZHANG
;
Chenyi TAO
;
Yong NING
;
Yi XU
;
Xiaodong JIA
;
Xia ZHANG
Author Information
1. Sepcial Populations Health Management Department, Shanghai Municipal Center for Disease Control and Prevention, Shanghai 200051, China
- Publication Type:Journal Article
- Keywords:
Legionella pneumophila;
Industrial recirculating cooling water;
Virulence factors;
Antimicrobial resistance
- From:
China Occupational Medicine
2026;53(1):50-57
- CountryChina
- Language:Chinese
-
Abstract:
Objective To analyze the genomic characteristics of Legionella pneumophila (L. pneumophila) isolated from industrial circulating cooling water in workplace. Methods A total of 20 L. pneumophila strains isolated from industrial circulating cooling water collected from eight chemical enterprises were selected as the research subjects. Whole-genome sequencing was performed on the strains, followed by multilocus sequence typing (MLST), whole-genome single nucleotide polymorphism analysis, virulence factor profiling, and antibiotic resistance gene detection. Results The dominant MLST typing among the 20 L. pneumophila strains was ST2. Serogroup 1 (Lp1) strains exhibited high genetic diversity. Strains from different enterprises showed substantial genomic diversity, suggesting possible inter-enterprise dissemination. Each isolate harbored 175-295 virulence genes; among them, virulence genes were identified, and 139 genes were detected in all the 20 strains. These genes primarily included those related to the Dot/Icm type Ⅳ bacterial secretion system, flagellar synthesis and motility, and type Ⅳ pili. The number of virulence genes carried by L. pneumophila strains of different ST types differed (P<0.01), with unidentified sequence types harboring more virulence genes than other STs (P<0.01). A total of four resistance genes were predicted, including aminoglycoside phosphotransferase-encoding gene APH(9)-Ia, carbapenemase-encoding gene OXA-29, and efflux pump genes-encoding genes LpeA and LpeB, with detection rates of 100.00%, 100.00%, 10.00%, and 10.00%, respectively. These genes may confer resistance to cephalosporins, penicillins, and aminoglycosides, and all strains were multidrug resistance. Conclusion L. pneumophila isolated from industrial recirculating cooling water exhibits high genetic diversity, strong pathogenicity, and significant multidrug resistance potential.
