Faculty Collaboration Database

Study of Legionella pneumophila treatment with copper in drinking water by single cell-ICP-MS. Anal Bioanal Chem 2024 Jan;416(2):419-430

Date

11/14/2023

Pubmed ID

37962610

Pubmed Central ID

PMC11077561

DOI

10.1007/s00216-023-05033-7

Scopus ID

2-s2.0-85176598224 (requires institutional sign-in at Scopus site)   3 Citations

Abstract

Legionella pneumophila is a persistent opportunistic pathogen that poses a significant threat to domestic water systems. Previous studies suggest that copper (Cu) is an effective antimicrobial in water systems. A rapid and sensitive quantification method is desired to optimize the conditions of L. pneumophila treatment by Cu and to better understand the interaction mechanisms between Cu and cells. In this study, we developed a highly sensitive single cell (SC)-ICP-MS method to monitor L. pneumophila cell concentration and track their uptake of Cu. The SC-ICP-MS method showed excellent sensitivity (with a cell concentration detection limit of 1000 cells/mL), accuracy (good agreement with conventional hemocytometry method), and precision (relative standard deviation < 5%) in drinking water matrix. The cupric ions (Cu²⁺) treatment results indicated that the total L. pneumophila cell concentration, Cu mass per cell, colony-forming unit counting, and Cu concentration in supernatant all exhibited a dose-dependent trend, with 800-1200 µg/L reaching high disinfection rates in drinking water. The investigation of percentages of viable and culturable, viable but nonculturable (VBNC), and lysed cells suggested there always were VBNC present at any Cu concentration. Experimental results of different Cu²⁺ treatment times further suggested that L. pneumophila cells developed an antimicrobial resistant mechanism with the prolonged Cu exposure. This is the first quantification study on the interactions of Cu and L. pneumophila in drinking water using SC-ICP-MS.

Author List

Xu L, Sigler A, Chernatynskaya A, Rasmussen L, Lu J, Sahle-Demessie E, Westenberg D, Yang H, Shi H

Author

Hu Yang PhD Chair, Professor in the Biomedical Engineering department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Anti-Infective Agents
Copper
Drinking Water
Legionella pneumophila
Water Microbiology
Water Supply