Evaluation of the new Id‐Fungi plates from Conidia for MALDI‐TOF MS identification of filamentous fungi and comparison with conventional methods as identification tool for dermatophytes from nails, hair and skin samples

ABSTRACT MALDI-TOF mass spectrometry (MS) identification of pathogenic filamentous fungi is often impaired by difficulties in harvesting hyphae embedded in the medium and long extraction protocols. The ID Fungi Plate (IDFP) is a novel culture method developed to address such difficulties and improve the identification of filamentous fungi by MALDI-TOF MS. We cultured 64 strains and 11 clinical samples on IDFP, Sabouraud agar-chloramphenicol (SAB), and ChromID Candida agar (CAN2). We then compared the three media for growth, ease of harvest, amount of material picked, and MALDI-TOF identification scores after either rapid direct transfer (DT) or a long ethanol-acetonitrile (EA) extraction protocol. Antifungal susceptibility testing and microscopic morphology after subculture on SAB and IDFP were also compared for ten molds. Growth rates and morphological aspects were similar for the three media. With IDFP, harvesting of fungal material for the extraction procedure was rapid and easy in 92.4% of cases, whereas it was tedious on SAB or CAN2 in 65.2% and 80.3% of cases, respectively. The proportion of scores above 1.7 (defined as acceptable identification) were comparable for both extraction protocols using IDFP (P = 0.256). Moreover, rates of acceptable identification after DT performed on IDFP (93.9%) were significantly higher than those obtained after EA extraction with SAB (69.7%) or CAN2 (71.2%) (P = <0.001 and P = 0.001, respectively). Morphological aspects and antifungal susceptibility testing were similar between IDFP and SAB. IDFP is a culture plate that facilitates and improves the identification of filamentous fungi, allowing accurate routine identification of molds with MALDI-TOF-MS using a rapid-extraction protocol.

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Determination of Drug Efflux Pump Efficiency in Drug-Resistant Bacteria Using MALDI-TOF MS

Antibiotics ◽

10.3390/antibiotics9100639 ◽

2020 ◽

Vol 9 (10) ◽

pp. 639 ◽

Cited By ~ 1

Author(s):

Wen-Jung Lu ◽

Hsuan-Ju Lin ◽

Pang-Hung Hsu ◽

Hong-Ting Victor Lin

Keyword(s):

Minimum Inhibitory Concentration ◽

Inhibitory Concentration ◽

Resistant Bacteria ◽

Pump Efficiency ◽

Drug Efflux ◽

Maldi Tof Ms ◽

E Coli ◽

Maldi Tof ◽

Conventional Methods ◽

Tof Ms

Multidrug efflux pumps play an essential role in antibiotic resistance. The conventional methods, including minimum inhibitory concentration and fluorescent assays, to monitor transporter efflux activity might have some drawbacks, such as indirect evidence or interference from color molecules. In this study, MALDI-TOF MS use was explored for monitoring drug efflux by a multidrug transporter, and the results were compared for validation with the data from conventional methods. Minimum inhibitory concentration was used first to evaluate the activity of Escherichia coli drug transporter AcrB, and this analysis showed that the E. coli overexpressing AcrB exhibited elevated resistance to various antibiotics and dyes. Fluorescence-based studies indicated that AcrB in E. coli could decrease the accumulation of intracellular dyes and display various efflux rate constants for different dyes, suggesting AcrB’s efflux activity. The MALDI-TOF MS analysis parameters were optimized to maintain a detection accuracy for AcrB’s substrates; furthermore, the MS data showed that E. coli overexpressing AcrB led to increased ions abundancy of various dyes and drugs in the extracellular space at different rates over time, illustrating continuous substrate efflux by AcrB. This study concluded that MALDI-TOF MS is a reliable method that can rapidly determine the drug pump efflux activity for various substrates.

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Assessment of various parameters to improve MALDI-TOF MS reference spectra libraries constructed for the routine identification of filamentous fungi

BMC Microbiology ◽

10.1186/1471-2180-13-76 ◽

2013 ◽

Vol 13 (1) ◽

pp. 76 ◽

Cited By ~ 70

Author(s):

Anne-Cécile Normand ◽

Carole Cassagne ◽

Stéphane Ranque ◽

Coralie L’Ollivier ◽

Patrick Fourquet ◽

...

Keyword(s):

Filamentous Fungi ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Routine Identification ◽

Tof Ms

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MALDI-TOF MS for identification of filamentous fungi

10.26226/morressier.56d6be7cd462b80296c958de ◽

2016 ◽

Author(s):

Rok Tomazin

Keyword(s):

Filamentous Fungi ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

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Multicenter evaluation of three different MALDI-TOF MS systems for identification of clinically relevant filamentous fungi

Medical Mycology ◽

10.1093/mmy/myaa037 ◽

2020 ◽

Vol 59 (1) ◽

pp. 81-86

Author(s):

Yue Sun ◽

Jian Guo ◽

Rong Chen ◽

Liang Hu ◽

Qihang Xia ◽

...

Keyword(s):

Sample Preparation ◽

Filamentous Fungi ◽

Reference Method ◽

Species Level ◽

Its Sequencing ◽

Maldi Tof Ms ◽

Genus Level ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Tof Ms

Abstract Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) holds promise as a potential tool for clinical identification of filamentous fungi. However, due to the lack of an appropriate extraction protocol and the difficulty of database building, the identification power of each system differs. In this study, we selected 126 clinical mould isolates comprising 28 species identified using internal transcribed spacer (ITS) sequencing as the reference method to evaluate three MALDI-TOF MS systems. When using cultures and sample preparation as recommended by the respective vendors, of the 126 strains tested, VITEK MS identified 121 (96.0%) to species-level and 124 (98.4%) to genus-level; Biotyper identified 53 (42.1%) to species-level and 54 (42.9%) to genus-level; Autof identified 74 (58.7%) to species-level and 76 (60.3%) to genus-level. For the Autof system, the tube extraction method recommended by the vendor performed better (59%) than the on-plate lysis (51%). Our study demonstrates that MALDI-TOF MS systems can successfully identify most clinically relevant fungi, while performance is still highly dependent on the database and sample preparation protocol.

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MALDI‑TOF MS for the rapid identification and drug susceptibility testing of filamentous fungi

Experimental and Therapeutic Medicine ◽

10.3892/etm.2019.8118 ◽

2019 ◽

Cited By ~ 2

Author(s):

Yang Peng ◽

Qin Zhang ◽

Chao Xu ◽

Weifeng Shi

Keyword(s):

Filamentous Fungi ◽

Susceptibility Testing ◽

Drug Susceptibility ◽

Rapid Identification ◽

Drug Susceptibility Testing ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

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MALDI-TOF MS: the proteomic approach, the future of fungal identification in India

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20202898 ◽

2020 ◽

Vol 8 (7) ◽

pp. 2575

Author(s):

Mallika Fonseca ◽

Sarala Menon ◽

Praveen Rahi ◽

Prachi Patekar ◽

Abhay S. Chowdhary

Keyword(s):

Yeast Species ◽

Fungal Infections ◽

Tertiary Care ◽

Turnaround Time ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Proteomic Approach ◽

Conventional Methods ◽

Tof Ms

Background: India, being a country where fungal infections are rampant, is urgently in need of effective tools for early and accurate diagnosis of fungal infections. Matrix-assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS) is a recent method which has shown potential in identifying clinically important bacterial pathogens as well as clinically important fungi. The main objective of this study was to compare the utility of MALDI-TOF MS for the identification of fungi against that of conventional methods.Methods: The project was carried out in a tertiary care government hospital in India. Fifty clinical isolates comprising mainly various yeast species were subjected to conventional identification (Phenotypic) as well as MALDI-TOF-MS. Their results were further compared.Results: MALDI-TOF MS showed a high concordance with conventional methods while identifying species like C. albicans, C. tropicalis, C. parapsilosis and C. neoformans, although the concordance for species such as Rhodotorula and Trichosporon could only be matched up to genus level.Conclusions: MALDI-TOF MS-based identification is both a rapid and a viable tool for identification of clinically relevant yeast species with good correlation to conventional methods and a quick turnaround time.

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Increased species-assignment of filamentous fungi using MALDI-TOF MS coupled with a simplified sample processing and an in-house library

Medical Mycology ◽

10.1093/mmy/myx154 ◽

2018 ◽

Vol 57 (1) ◽

pp. 63-70 ◽

Cited By ~ 12

Author(s):

M E Zvezdanova ◽

P Escribano ◽

A Ruiz ◽

M C Martínez-Jiménez ◽

T Peláez ◽

...

Keyword(s):

Filamentous Fungi ◽

Sample Processing ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Species Assignment ◽

Tof Ms

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Identification of Candida albicans species complex in vulvovaginal candidiasis by using conventional methods, hwp1 gene polymorphisms and MALDI-TOF MS profiles

10.26226/morressier.5b27c6725632c90ddabfce7e ◽

2018 ◽

Author(s):

E. Nasri

Keyword(s):

Candida Albicans ◽

Gene Polymorphisms ◽

Species Complex ◽

Vulvovaginal Candidiasis ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Conventional Methods ◽

Tof Ms

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Species Identification and Delineation of Pathogenic Mucorales by Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry

Journal of Clinical Microbiology ◽

10.1128/jcm.01886-17 ◽

2018 ◽

Vol 56 (4) ◽

pp. e01886-17 ◽

Cited By ~ 12

Author(s):

Jin Shao ◽

Zhe Wan ◽

Ruoyu Li ◽

Jin Yu

Keyword(s):

Filamentous Fungi ◽

Laser Desorption ◽

Laser Desorption Ionization ◽

Ionization Time ◽

Content Type ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Reference Strains ◽

Tof Ms

ABSTRACT This study aimed to validate the effectiveness of matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS)-based identification of filamentous fungi of the order Mucorales. A total of 111 isolates covering six genera preserved at the Research Center for Medical Mycology of Peking University were selected for MALDI-TOF MS analysis. We emphasized the study of 23 strains of Mucor irregularis predominantly isolated from patients in China. We first used the Bruker Filamentous Fungi library (v1.0) to identify all 111 isolates. To increase the identification rate, we created a compensatory in-house database, the Beijing Medical University (BMU) database, using 13 reference strains covering 6 species, including M. irregularis, Mucor hiemalis, Mucor racemosus, Cunninghamella bertholletiae, Cunninghamella phaeospora, and Cunninghamella echinulata. All 111 isolates were then identified by MALDI-TOF MS using a combination of the Bruker library and BMU database. MALDI-TOF MS identified 55 (49.5%) and 74 (66.7%) isolates at the species and genus levels, respectively, using the Bruker Filamentous Fungi library v1.0 alone. A combination of the Bruker library and BMU database allowed MALDI-TOF MS to identify 90 (81.1%) and 111 (100%) isolates at the species and genus levels, respectively, with a significantly increased accuracy rate. MALDI-TOF MS poorly identified Mucorales when the Bruker library was used alone due to its lack of some fungal species. In contrast, this technique perfectly identified M. irregularis after main spectrum profiles (MSPs) of relevant reference strains were added to the Bruker library. With an expanded Bruker library, MALDI-TOF MS is an effective tool for the identification of pathogenic Mucorales.

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