Molecular analysis of volatile metabolites released specifically by staphylococcus aureus and pseudomonas aeruginosa

BMC Microbiology

Research Article

Andreas Sponring¹  Maria Magdalena Baur¹  Anna Filipiak¹  Clemens Ager¹  Anton Amann¹  Wojciech Filipiak¹  Helmut Wiesenhofer¹  Jakob Troppmair²  Markus Nagl³ 

[1] Breath Research Institute of the Austrian Academy of Sciences, Rathausplatz 4, A-6850, Dornbirn, Austria;Univ. Clinic for Anesthesia, Innsbruck Medical University, Anichstr. 35, A-6020, Innsbruck, Austria;Daniel-Swarovski Research Laboratory, Department of Visceral-, Transplant- and Thoracic Surgery, Innsbruck Medical University, Innrain 66, A-6020, Innsbruck, Austria;Department of Hygiene, Microbiology and Social Medicine, Division of Hygiene and Medical Microbiology, Innsbruck Medical University, Fritz-Preglstraße 3, A-6020, Innsbruck, Austria;

关键词: Volatile organic compounds (VOCs);    Gas chromatography mass spectrometry (GCMS);    Breath analysis;    In vitro;    Adsorptive enrichment;    Multibed sorption tubes;    Volatile metabolites;    Staphylococcus aureus;    Pseudomonas aeruginosa;   

DOI  :  10.1186/1471-2180-12-113

 received in 2012-02-24, accepted in 2012-06-20,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundThe routinely used microbiological diagnosis of ventilator associated pneumonia (VAP) is time consuming and often requires invasive methods for collection of human specimens (e.g. bronchoscopy). Therefore, it is of utmost interest to develop a non-invasive method for the early detection of bacterial infection in ventilated patients, preferably allowing the identification of the specific pathogens. The present work is an attempt to identify pathogen-derived volatile biomarkers in breath that can be used for early and non- invasive diagnosis of ventilator associated pneumonia (VAP). For this purpose, in vitro experiments with bacteria most frequently found in VAP patients, i.e. Staphylococcus aureus and Pseudomonas aeruginosa, were performed to investigate the release or consumption of volatile organic compounds (VOCs).ResultsHeadspace samples were collected and preconcentrated on multibed sorption tubes at different time points and subsequently analyzed with gas chromatography mass spectrometry (GC-MS). As many as 32 and 37 volatile metabolites were released by S. aureus and P. aeruginosa, respectively. Distinct differences in the bacteria-specific VOC profiles were found, especially with regard to aldehydes (e.g. acetaldehyde, 3-methylbutanal), which were taken up only by P. aeruginosa but released by S. aureus. Differences in concentration profiles were also found for acids (e.g. isovaleric acid), ketones (e.g. acetoin, 2-nonanone), hydrocarbons (e.g. 2-butene, 1,10-undecadiene), alcohols (e.g. 2-methyl-1-propanol, 2-butanol), esters (e.g. ethyl formate, methyl 2-methylbutyrate), volatile sulfur compounds (VSCs, e.g. dimethylsulfide) and volatile nitrogen compounds (VNCs, e.g. 3-methylpyrrole).Importantly, a significant VOC release was found already 1.5 hours after culture start, corresponding to cell numbers of ~8*106 [CFUs/ml].ConclusionsThe results obtained provide strong evidence that the detection and perhaps even identification of bacteria could be achieved by determination of characteristic volatile metabolites, supporting the clinical use of breath-gas analysis as non-invasive method for early detection of bacterial lung infections.

【 授权许可】

Unknown   
© Filipiak et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.