Comparative Analysis of Proteome Patterns of Francisella tularensis Isolates from Patients and the Environment

Abstract

Francisella tularensis is the causative agent of tularemia. Although major contributors and the main mechanism of the virulence are well known, some of the molecular details are still missing. Proteomics studies regarding F. tularensis have provided snapshot pictures of the organism grown under different culture conditions to understand the mechanism of virulence. In general, such studies were carried out with standard strains e.g., LVS and did not involve comparisons of F. tularensis isolates from either clinical or environmental sources. In this study, we performed two-dimensional gel electrophoresis (2DE)-based proteomic analysis and compared the protein profiles of the F. tularensis subsp. holarctica strains isolated from the clinical and the environmental samples. Regulations were detected in 14 spots when twofold regulation criteria were applied. The regulated protein spots were subjected to MALDI-TOF/TOF analysis and identified. Classification of the identified proteins based on metabolic functions revealed that the translation machinery was the most varying metabolic processes among the isolates. Using normalized protein spot intensities, PCA analysis was also performed. The results indicated that the strain isolated from water source was different then the strains isolated from the patients. Most interestingly, the isolates were strikingly distinguishable from the standard NCTC 10857 strain.

Molecular epidemiology of Colombian Histoplasma capsulatum isolates obtained from human and chicken manure samples

“…Nowadays, it is possible to compare isolates using the proteomic analysis. This approach could be used to elucidate genes related to pathogenicity by comparing gene expression and activity in environmental and clinical isolates (Kasap et al., 2017; Montagna et al., 2018; Jun et al., 2013). If the virulence genes have been not activated in the environmental isolates in the same form as in the clinical isolates, then the use of the mouse model for the isolation of H. capsulatum from environmental samples needs to be reconsidered as the gold standard technique.…”

Molecular epidemiology of ColombianHistoplasma capsulatumisolates shows their polyphyletic behavior and point out raw chicken manure as one of the infections sources

“…Nowadays, it is possible to compare isolates using the proteome analysis. This approach could be used to elucidate genes related to pathogenicity by comparing gene activity in environmental and clinical isolates (55-57). If environmental isolates have not activated the virulence genes like the clinical isolates, then the use of the mouse model for the isolation of H. capsulatum from environmental samples would need to be reconsidered to be the gold standard technique .…”

Rapid and Culture Free Identification of Francisella in Hare Carcasses by High-Resolution Tandem Mass Spectrometry Proteotyping

“…Cultivation of bacteria in biosafety levels 2 and 3 laboratories is the gold standard for diagnosing these pathogens and allows subsequent typing of bacteria, e.g., with PCR assays and other DNA-based techniques. Currently, matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) approaches are commonly used to identify Francisella in an automated way at low costs in a very short time (Hubalek et al, 2004;Kilmury and Twine, 2010;Seibold et al, 2010;Durighello et al, 2014;Karatuna et al, 2016;Kasap et al, 2017). However, only pure isolates can be identified, adequate reference databases are required, and some species cannot be discriminated against due to their close phylogenetic relationship.…”