Identification of phlebotomine sand flies using one MALDI-TOF MS reference database and two mass spectrometer systems

AbstractAspergillus section Nigri is a taxonomically difficult but medically and economically important group. In this study, an update of the taxonomy of A. section Nigri strains within the BCCM/IHEM collection has been conducted. The identification accuracy of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was tested and the antifungal susceptibilities of clinical isolates were evaluated. A total of 175 strains were molecularly analyzed. Three regions were amplified (ITS, benA, and caM) and a multi-locus phylogeny of the combined loci was created by using maximum likelihood analysis. The in-house MALDI-TOF MS reference database was extended and an identification data set of 135 strains was run against a reference data set. Antifungal susceptibility was tested for voriconazole, itraconazole, and amphotericin B, using the EUCAST method. Phylogenetic analysis revealed 18 species in our data set. MALDI-TOF MS was able to distinguish between A. brasiliensis, A. brunneoviolaceus, A. neoniger, A. niger, A. tubingensis, and A. welwitschiae of A. sect. Nigri. In the routine clinical lab, isolates of A. sect. Nigri are often identified as A. niger. However, in the clinical isolates of our data set, A. tubingensis (n = 35) and A. welwitschiae (n = 34) are more common than A. niger (n = 9). Decreased antifungal susceptibility to azoles was observed in clinical isolates of the /tubingensis clade. This emphasizes the importance of identification up to species level or at least up to clade level in the clinical lab. Our results indicate that MALDI-TOF MS can be a powerful tool to replace classical morphology.

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Identification of phlebotomine sand flies through MALDI-TOF mass spectrometry and in-house reference database

Acta Tropica ◽

10.1016/j.actatropica.2019.03.015 ◽

2019 ◽

Vol 194 ◽

pp. 47-52 ◽

Cited By ~ 2

Author(s):

Francesca Arfuso ◽

Gabriella Gaglio ◽

Jessica Maria Abbate ◽

Giulia Caracappa ◽

Angelo Lupia ◽

...

Keyword(s):

Mass Spectrometry ◽

Reference Database ◽

Sand Flies ◽

Phlebotomine Sand Flies ◽

Maldi Tof Mass Spectrometry ◽

Maldi Tof

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Reagent-Free Identification of Clinical Yeasts by Use of Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy

Journal of Clinical Microbiology ◽

10.1128/jcm.01739-18 ◽

2019 ◽

Vol 57 (5) ◽

Author(s):

Lisa M. T. Lam ◽

Philippe J. Dufresne ◽

Jean Longtin ◽

Jacqueline Sedman ◽

Ashraf A. Ismail

Keyword(s):

Fourier Transform ◽

Ftir Spectroscopy ◽

Fourier Transform Infrared ◽

Attenuated Total Reflectance ◽

Reference Database ◽

Accurate Identification ◽

Total Reflectance ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

ABSTRACT Invasive fungal infections by opportunistic yeasts have increased concomitantly with the growth of an immunocompromised patient population. Misidentification of yeasts can lead to inappropriate antifungal treatment and complications. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy is a promising method for rapid and accurate identification of microorganisms. ATR-FTIR spectroscopy is a standalone, inexpensive, reagent-free technique that provides results within minutes after initial culture. In this study, a comprehensive spectral reference database of 65 clinically relevant yeast species was constructed and tested prospectively on spectra recorded (from colonies taken from culture plates) for 318 routine yeasts isolated from various body fluids and specimens received from 38 microbiology laboratories over a 4-month period in our clinical laboratory. ATR-FTIR spectroscopy attained comparable identification performance with matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS). In a preliminary validation of the ATR-FTIR method, correct identification rates of 100% and 95.6% at the genus and species levels, respectively, were achieved, with 3.5% unidentified and 0.9% misidentified. By expanding the number of spectra in the spectral reference database for species for which isolates could not be identified or had been misidentified, we were able to improve identification at the species level to 99.7%. Thus, ATR-FTIR spectroscopy provides a new standalone method that can rival MALDI-TOF MS for the accurate identification of a broad range of medically important yeasts. The simplicity of the ATR-FTIR spectroscopy workflow favors its use in clinical laboratories for timely and low-cost identification of life-threatening yeast strains for appropriate treatment.

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Maldi mass spectrometry for identification lactic acid bacilli isolated from lactic acid products produced in the Karagandy region

Bulletin of the Karaganda University. “Biology, medicine, geography Series” ◽

10.31489/2021bmg3/18-25 ◽

2021 ◽

Vol 103 (3) ◽

pp. 18-25

Author(s):

Zhanar Amirkhanova ◽

◽

Rahat Bodeeva ◽

Saule Akhmetova ◽

Altynay Tuyakova ◽

...

Keyword(s):

Mass Spectrometry ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Mass Spectrometer ◽

Cottage Cheese ◽

Spectrometric Method ◽

Mass Spectrometric Method ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

At present the traditional methods of identifying microorganisms are replaced by express methods, the mass spectrometric method using MALDI-TOF MS allows to reliably identify a variety of microorganisms in a short time, which is an indisputable advantage in work and allows to quickly identify many microorganisms in quickly. Classical methods for the identification of lactic acid bacteria based on their cultivation require a long time for their implementation. The advent of matrix laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) technology made significant changes in the workflows for the study of lactic acid bacteria, unmatched in speed characteristics. This article presents the study of the morphological, cultural properties, acid-forming ability, antibiotic sensitivity lactic acid bacteria of isolated from products (ayran, koumiss, ashykan kozhe, kurt, suzbe, cottage cheese) produced in different districts of the Karaganda region. The species identification of the isolated strains of lactic acid bacteria was carried out using a MALDI-TOF mass spectrometer. The studies carried out on cultural and morphological characters indicate that they belong to the genus Lactobacillus, Lacticaseibacillus, Lactiplantibacillus, Limosilactobacillus. As a result of identification on the mass spectrometer of the presented samples L. acidophilus (2 strains), L. delbrueckii subsp. bulgaricum (2 strains), L. rhamnosus (7 strains), L. plantarum (2 strains), L. paracasei (11 strains), L. fermentum (2 strains) were revealed. According to the Score values, the results indicate the accuracy of the identification.

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Integrative Approach to Phlebotomus mascittii Grassi, 1908: First Record in Vienna with New Morphological and Molecular Insights

Pathogens ◽

10.3390/pathogens9121032 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1032

Author(s):

Edwin Kniha ◽

Vít Dvořák ◽

Petr Halada ◽

Markus Milchram ◽

Adelheid G. Obwaller ◽

...

Keyword(s):

First Record ◽

Protein Profiling ◽

Sand Fly ◽

Integrative Approach ◽

Marker Genes ◽

Morphological Identification ◽

Sand Flies ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

Sand flies (Diptera: Psychodidae: Phlebotominae) are blood-feeding insects that transmit the protozoan parasites Leishmania spp. and various arthropod-borne (arbo) viruses. While in Mediterranean parts of Europe the sand fly fauna is diverse, in Central European countries including Austria mainly Phlebotomus mascittii is found, an assumed but unproven vector of Leishmania infantum. To update the currently understudied sand fly distribution in Austria, a sand fly survey was performed and other entomological catches were screened for sand flies. Seven new trapping locations of Ph. mascittii are reported including the first record in Vienna, representing also one of the first findings of this species in a city. Morphological identification, supported by fluorescence microscopy, was confirmed by two molecular approaches, including sequencing and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) protein profiling. Sand fly occurrence and activity were evaluated based on surveyed locations, habitat requirements and climatic parameters. Moreover, a first comparison of European Ph. mascittii populations was made by two marker genes, cytochrome c oxidase subunit 1 (COI), and cytochrome b (cytb), as well as MALDI-TOF mass spectra. Our study provides new important records of Ph. mascittii in Austria and valuable data for prospective entomological surveys. MALDI-TOF MS protein profiling was shown to be a reliable tool for differentiation between sand fly species. Rising temperatures and globalization demand for regular entomological surveys to monitor changes in species distribution and composition. This is also important with respect to the possible vector competence of Ph. mascittii.

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Using MALDI-ToF mass spectrometry to identify mushroom species: Proof of concept analysis of Amanita genus specimens

Medical Mycology ◽

10.1093/mmy/myab018 ◽

2021 ◽

Author(s):

Raphael Piarroux ◽

Frédéric Gabriel ◽

Frédéric Grenouillet ◽

Patrick Collombon ◽

Philippe Louasse ◽

...

Keyword(s):

Mass Spectrometry ◽

Food Poisoning ◽

Laser Desorption ◽

Reference Database ◽

Laser Desorption Ionization ◽

Ionization Time ◽

Maldi Tof Ms ◽

The Past ◽

Maldi Tof ◽

Tof Ms

Abstract Food poisoning caused by toxic mushrooms, such as species in the Amanita genus, occurs frequently around the world. To properly treat these patients, it is important to rapidly and accurately identify the causal species. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectrometry is a rapid technique that has been used in medical laboratories for the past three decades to identify bacteria, yeasts, and filamentous fungi. Matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-Tof MS) is a rapid method used for the past three decades to identify microorganisms. In this study, we created and internally validated a MALDI-Tof MS reference database comprising 15 Amanita species frequently encountered in France, and we challenged this database with 38 Amanita specimens from four French locations, using a free online application for MALDI-ToF spectra identifications. Assessment of the database showed that mass spectra can be obtained by analyzing any portion of a carpophore and that all portions enabled identification of the carpophore at the species level. Most carpophores were correctly identified using our database, with the exception of specimens from the Vaginatae section. Decay tests also demonstrated that decayed portions (like those found in the kitchen garbage can) of Amanita phalloides mushrooms could be properly identified using MALDI-ToF MS. Our findings provide important insight for toxicology laboratories that often rely on DNA sequencing to identify meal leftovers implicated in food poisoning. In future developments, this technique could also be used to detect counterfeit mushrooms by including other genera in the reference database. Lay Summary MALDI-ToF MS is a powerful identification tool for microorganisms. We demonstrate that the technique can be applied to Amanita specimens. This will prevent food intoxications as a rapid and definite identification can be obtained, and it can also be used for food remnants.

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Identification of Photorhabdus symbionts by MALDI-TOF MS

Microbiology ◽

10.1099/mic.0.000905 ◽

2020 ◽

Vol 166 (6) ◽

pp. 522-530

Author(s):

Virginia Hill ◽

Peter Kuhnert ◽

Matthias Erb ◽

Ricardo A. R. Machado

Keyword(s):

Related Species ◽

Species Level ◽

Reference Database ◽

Agricultural Pests ◽

Closely Related Species ◽

Content Type ◽

Maldi Tof Ms ◽

Link Type ◽

Maldi Tof ◽

Tof Ms

Species of the bacterial genus Photorhabus live in a symbiotic relationship with Heterorhabditis entomopathogenic nematodes. Besides their use as biological control agents against agricultural pests, some Photorhabdus species are also a source of natural products and are of medical interest due to their ability to cause tissue infections and subcutaneous lesions in humans. Given the diversity of Photorhabdus species, rapid and reliable methods to resolve this genus to the species level are needed. In this study, we evaluated the potential of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for the identification of Photorhabdus species. To this end, we established a collection of 54 isolates consisting of type strains and multiple field strains that belong to each of the validly described species and subspecies of this genus. Reference spectra for the strains were generated and used to complement a currently available database. The extended reference database was then used for identification based on the direct transfer sample preparation method and the protein fingerprint of single colonies. High-level discrimination of distantly related species was observed. However, lower discrimination was observed with some of the most closely related species and subspecies. Our results therefore suggest that MALDI-TOF MS can be used to correctly identify Photorhabdus strains at the genus and species level, but has limited resolution power for closely related species and subspecies. Our study demonstrates the suitability and limitations of MALDI-TOF-based identification methods for assessment of the taxonomic position and identification of Photorhabdus isolates.

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Differentiation of Gastric Helicobacter Species Using MALDI-TOF Mass Spectrometry

Pathogens ◽

10.3390/pathogens10030366 ◽

2021 ◽

Vol 10 (3) ◽

pp. 366

Author(s):

Helena Berlamont ◽

Chloë De Witte ◽

Sofie De Bruyckere ◽

James G. Fox ◽

Steffen Backert ◽

...

Keyword(s):

Species Identification ◽

Growth Conditions ◽

Reference Database ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Animal Pathogens ◽

H Pylori ◽

Specific Species ◽

Individual Mass ◽

Tof Ms

Gastric helicobacters (Helicobacter (H.) pylori and non-H. pylori Helicobacter species (NHPHs)) colonize the stomach of humans and/or animals. Helicobacter species identification is essential since many of them are recognized as human and/or animal pathogens. Currently, Helicobacter species can only be differentiated using molecular methods. Differentiation between NHPHs using MALDI-TOF MS has not been described before, probably because these species are poorly represented in current MALDI-TOF MS databases. Therefore, we identified 93 gastric Helicobacter isolates of 10 different Helicobacter species using MALDI-TOF MS in order to establish a more elaborate Helicobacter reference database. While the MALDI Biotyper database was not able to correctly identify any of the isolates, the in-house database correctly identified all individual mass spectra and resulted in 82% correct species identification based on the two highest log score matches (with log scores ≥2). In addition, a dendrogram was constructed using all newly created main spectrum profiles. Nine main clusters were formed, with some phylogenetically closely related Helicobacter species clustering closely together and well-defined subclusters being observed in specific species. Current results suggest that MALDI-TOF MS allows rapid differentiation between gastric Helicobacter species, provided that an extensive database is at hand and variation due to growth conditions and agar-medium-related peaks are taken into account.

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