Mass Spectrometry Proteotyping-Based Detection and Identification of Staphylococcus aureus, Escherichia coli, and Candida albicans in Blood

Frontiers in Cellular and Infection Microbiology

Björn Andersson¹  Edward R. B. Moore²  Daniel Jaén-Luchoro²  Amra Kurtovic³  Nahid Kondori³  Beatriz Piñeiro-Iglesias³  Timur Tunovic³  Francisco Salvà-Serra⁵  Roger Karlsson⁶  Anders Karlsson⁶  Aleksey Ogurtsov⁷  Yi-Kuo Yu⁷  Gelio Alves⁷  Nina Kamenska⁸  Johannes Fuchs⁹  Annika Thorsell⁹ 

[1] Bioinformatics Core Facility at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden;Culture Collection University of Gothenburg (CCUG), Sahlgrenska Academy of the University of Gothenburg, Gothenburg, Sweden;Department of Clinical Microbiology, Sahlgrenska University Hospital, Gothenburg, Sweden;Department of Infectious Diseases, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden;Microbiology, Department of Biology, University of the Balearic Islands, Palma de Mallorca, Spain;Nanoxis Consulting AB, Gothenburg, Sweden;National Center for Biotechnology Information (NCBI), Bethesda, MD, United States;Norra-Älvsborgs-Länssjukhus (NÄL), Trollhättan, Sweden;Proteomics Core Facility at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden;

关键词: blood-stream infections;    proteotyping;    MALDI-TOF MS;    proteomics;    bacteremia;    fungemia;   

DOI  :  10.3389/fcimb.2021.634215

来源: DOAJ

【 摘 要 】

Bloodstream infections (BSIs), the presence of microorganisms in blood, are potentially serious conditions that can quickly develop into sepsis and life-threatening situations. When assessing proper treatment, rapid diagnosis is the key; besides clinical judgement performed by attending physicians, supporting microbiological tests typically are performed, often requiring microbial isolation and culturing steps, which increases the time required for confirming positive cases of BSI. The additional waiting time forces physicians to prescribe broad-spectrum antibiotics and empirically based treatments, before determining the precise cause of the disease. Thus, alternative and more rapid cultivation-independent methods are needed to improve clinical diagnostics, supporting prompt and accurate treatment and reducing the development of antibiotic resistance. In this study, a culture-independent workflow for pathogen detection and identification in blood samples was developed, using peptide biomarkers and applying bottom-up proteomics analyses, i.e., so-called “proteotyping”. To demonstrate the feasibility of detection of blood infectious pathogens, using proteotyping, Escherichia coli and Staphylococcus aureus were included in the study, as the most prominent bacterial causes of bacteremia and sepsis, as well as Candida albicans, one of the most prominent causes of fungemia. Model systems including spiked negative blood samples, as well as positive blood cultures, without further culturing steps, were investigated. Furthermore, an experiment designed to determine the incubation time needed for correct identification of the infectious pathogens in blood cultures was performed. The results for the spiked negative blood samples showed that proteotyping was 100- to 1,000-fold more sensitive, in comparison with the MALDI-TOF MS-based approach. Furthermore, in the analyses of ten positive blood cultures each of E. coli and S. aureus, both the MALDI-TOF MS-based and proteotyping approaches were successful in the identification of E. coli, although only proteotyping could identify S. aureus correctly in all samples. Compared with the MALDI-TOF MS-based approaches, shotgun proteotyping demonstrated higher sensitivity and accuracy, and required significantly shorter incubation time before detection and identification of the correct pathogen could be accomplished.

【 授权许可】

Unknown