A case of CAPD peritonitis in which <i>Streptococcus vestibularis</i> was found to be the causative agent by MALDI‒TOF MS

AbstractTheBacillus(B.)cereusgroup is genetically highly homogenous and consists of nine recognized species which are present worldwide.B. cereussensu stricto play an important role in food-borne diseases by producing different toxins. Yet, only a small percentage ofB. cereusstrains are able to produce the heat stable depsipeptide cereulide, the causative agent of emetic food poisonings. To minimize the entry of emeticB. cereusinto the food chain, food business operators are dependent on efficient and reliable methods enabling the differentiation between emetic and non-emetic strains. Currently, only time-consuming cell bioassays, molecular methods and tandem mass spectrometry are available for this purpose. Thus, the aim of the present study was to establish a fast and reliable method for the differentiation between emetic and non-emetic strains by MALDI-TOF MS. Selected isolates/strains of theB. cereusgroup (total n=110, i.e. emetic n=45, non-emetic n=65) were cultured on sheep blood agar for 48h.Subsequently, the cultures were directly analyzed by MALDI-TOF MS without prior extraction steps (direct smear method). The samples were measured in linear positive ionization mode in the mass range ofm/z800 - 1,800 Da. Using ClinProTools 3.0 statistical software and flex analyst, a differentiation between emetic and non-emetic isolates was possible with a rate of correct identification of 99.1 % by means of the evaluation of two specific biomarkers (m/z1171 and 1187 Da).ImportanceBacillus(B.)cereusplays an important role in food-borne diseases due to the production of different toxins, e.g. the heat stable depsipeptide cereulide. Only a small number ofB. cereusstrains are able to produce this toxin, the causative agent of emetic food poisonings. To minimize the entry of emeticB. cereusinto the food chain, food business operators require efficient and reliable methods enabling the differentiation between emetic and non-emetic strains. The aim of the present study was to develop a fast and reliable method for the differentiation between emetic and non-emetic strains by MALDI-TOF MS. A differentiation between emetic and non-emetic isolates was possible with a rate of correct identification of 99.1 % by means of the evaluation of two specific biomarkers (m/z1171 and 1187 Da).

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MALDI-TOF MS for rapid diagnosis of Anaerobiospirillum succiniciproducens, an unusual causative agent of bacteraemia in humans. Two case reports and literature review

Anaerobe ◽

10.1016/j.anaerobe.2018.12.003 ◽

2019 ◽

Vol 55 ◽

pp. 130-135 ◽

Cited By ~ 3

Author(s):

Marina Alguacil-Guillen ◽

Luis Ramos-Ruperto ◽

Juan Carlos Ramos Ramos ◽

Angel Robles-Marhuenda ◽

Julio García-Rodriguez ◽

...

Keyword(s):

Literature Review ◽

Causative Agent ◽

Case Reports ◽

Rapid Diagnosis ◽

Maldi Tof Ms ◽

Anaerobiospirillum Succiniciproducens ◽

Maldi Tof ◽

Tof Ms

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APPLICATION OF TIME-OF-FLIGHT MASS-SPECTROMETRY FOR DETECTION OF CAUSATIVE AGENT OF BRUCELLOSIS IN BLOOD SAMPLES IN EXPERIMENT

Journal of microbiology epidemiology immunobiology ◽

10.36233/0372-9311-2017-4-9-17 ◽

2017 ◽

pp. 9-17

Author(s):

D. V. Ulshina ◽

D. A. Kovalev ◽

D. G. Ponomarenko ◽

D. V. Rusanova ◽

N. M. Shvetsova ◽

...

Keyword(s):

Mass Spectrometry ◽

Causative Agent ◽

Brucella Melitensis ◽

Time Of Flight ◽

Protein Profiling ◽

Blood Samples ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Tof Ms

Aim.Study the possibility to apply time-of-flight mass-spectrometry for detection of causative agent of brucellosis in blood. Materials and methods. Brucella strains: 5 Brucella melitensis and 21 Brucella abortus. Protein profiling in linear mode on MALD1-TOF mass-spectrometer Microflex «Bruker Daltonics». Results. Technique for disinfection and preparation of blood samples was modified and optimized for MALDI-TOF MS analysis. 120 representative protein profiles of sera extract were obtained that contain brucellosis causative agent. A resulting peak-list (super-spectrum) of the studied protein fraction of blood extract of a conditionally healthy human within the studied group was formed and analyzed. Conclusion. A scheme of brucella detection in blood samples by MALDI-TOF MS is proposed, based on detection of a complex of 15 genus-specific fragments. Signals on mass-spectra of extracts of leukocyte fraction of blood, artificially contaminated with brucellosis causative agents are characterized.

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STUDY OF THE MASS-SPECTORS’ FEATURES OF SPORES AND VEGETATIVE FORMS OF BACILLUS ANTHRACIS BY THE METHOD OF TIME OF FLIGHT MASS-SPECTROMETRY

Journal of microbiology epidemiology immunobiology ◽

10.36233/0372-9311-2018-6-66-72 ◽

2018 ◽

pp. 66-72

Author(s):

D. V. Ulshina ◽

E. I. Eremenko ◽

D. A. Kovalev ◽

A. G. Ryazanova ◽

I. V. Kuznetsova ◽

...

Keyword(s):

Bacillus Anthracis ◽

Causative Agent ◽

Protein Profiling ◽

Protein Profiles ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Vegetative Form ◽

Maldi Tof Mass Spectra ◽

Tof Ms

Aim. Investigation of the features of the protein profiles of the spore and vegetative form of the anthrax microbe by the MALDI-TOF MS method using the resources of the Mass-Up program and the package for the statistical software with open source code R. Materials and methods. Spores and vegetative forms of 32 strains of B. anthracis from the collection of microorganisms of the Stavropol Research Institute for Plague Control, including 8 strains isolated from an outbreak of anthrax in Yamal in 2016. Protein profiling was carried out on the Microflex MALDI-TOF mass spectrometer «Bruker Daltonics». Results. The alternative bioinformational-statistical approach used to analyze the MALDI-TOF mass spectra of the causative agent of anthrax made it possible to differentiate the spores and vegetative forms of the microbe based on the identification of the corresponding groups of biomarkers. Conclusion. A comparison of vegetative and spore cells of typical and atypical strains of anthrax causative agent on the basis of MALDI-TOF MS data was made. It has been experimentally confirmed that the protein profiles of cultures of Bacillus anthracis of the spore and vegetative form differ significantly, and this difference can be used to search for potential markers of each of the forms.

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