scholarly journals Identification of CMY-2-Type Cephalosporinases in Clinical Isolates of Enterobacteriaceae by MALDI-TOF MS

2014 ◽  
Vol 58 (5) ◽  
pp. 2952-2957 ◽  
Author(s):  
C. C. Papagiannitsis ◽  
S. D. Kotsakis ◽  
Z. Tuma ◽  
M. Gniadkowski ◽  
V. Miriagou ◽  
...  
Keyword(s):  
Clinical Isolates ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms

Black aspergilli: A remaining challenge in fungal taxonomy?

2018 ◽  
Vol 57 (6) ◽  
pp. 773-780 ◽  
Author(s):  
Elizabet D’hooge ◽  
Pierre Becker ◽  
Dirk Stubbe ◽  
Anne-Cécile Normand ◽  
Renaud Piarroux ◽  
...  
Keyword(s):  
Antifungal Susceptibility ◽  
Identification Accuracy ◽  
Clinical Isolates ◽  
Reference Database ◽  
Data Set ◽  
Ionization Time ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
Tof Ms

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.

scholarly journals Cytosolic Proteome Profiling of Aminoglycosides Resistant Mycobacterium tuberculosis Clinical Isolates Using MALDI-TOF/MS

2016 ◽  
Vol 7 ◽  
Author(s):  
Divakar Sharma ◽  
Manju Lata ◽  
Rananjay Singh ◽  
Nirmala Deo ◽  
Krishnamurthy Venkatesan ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Clinical Isolates ◽  
Maldi Tof Ms ◽  
Proteome Profiling ◽  
Maldi Tof ◽  
Tof Ms

Clinical and microbiological characteristics of Cryptococcus gattii isolated from China

2020 ◽  
Author(s):  
Liang Jin ◽  
Jingrong Cao ◽  
Xinying Xue ◽  
Hua Wu ◽  
Lifeng Wang ◽  
...  
Keyword(s):  
Antifungal Agents ◽  
Antifungal Susceptibility ◽  
The United States ◽  
Cryptococcus Gattii ◽  
Clinical Isolates ◽  
Strain Identification ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Significant Difference ◽  
Tof Ms

Abstract Background: Infection, even outbreak, caused by Cryptococcus gattii (C. gattii ) has been reported in Canada and the United States, but there were sparsely-reported cases of C. gattii in China. Our interest in occurrence, clinical manifestation, laboratory identification and molecular characterization of Chinese C. gattii strains leads us to this research. Methods: A total of 254 clinical isolates primarily identified as Cryptococcus neoformans (C. neoformans ) were collected. VITEK 2 compact, canavanine glycine bromothymol blue (CGB) agar and Bruker Biotyper matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) were used for strain identification. Multi-locus sequence typing (MLST) was performed for genotyping. Antifungal susceptibility test was carried out with commercial kits of both ATB fungus 3 and Yeast one. Clinical information of patients was reviewed retrospectively. Label-free proteome technique was used to quantitatively analyze the differential proteins of C. gattii. Results: Out of 254 clinical isolates, we identified eight strains as C. gattii. MLST showed genotype VGI accounted for the most (6 / 8), the other two strains were genotype VGII（VGIIa and VGIIb respectively）with 3 specific spectra of molecular weight about 4342, 8686, 9611 Dalton by MALDI-TOF MS. The minimal inhibitory concentrations (MICs) of Fluconazole with Yeast one was 2～4 times higher than that with ATB fungus 3. Higher MICs of antifungal agents were exhibited against VGII strains than against VGI strains. C. gattii genotype VGII and VGI possessed 418 and 774 specific proteins respectively. Comparative proteome analysis showed that 180 proteins were highly expressed in C. gattii VGII and 329 proteins were highly expressed in C. gattii VGI. The enrichment of differentially expressed proteins between VGII and VGI was directed to Golgi complex.Conclusions: Infection by C. gattii in China might have been underestimated because of initial mis-identification. Genotype VGI was predominant but VGII was more resistant to antifungal agents. There was significant difference in protein expression profile between VGII and VGI C. gattii.

Performance of MALDI-ToF MS for species identification of Burkholderia cepacia complex clinical isolates

2013 ◽  
Vol 77 (2) ◽  
pp. 126-128 ◽  
Author(s):  
Lorena Cristina Corrêa Fehlberg ◽  
Lucas Henrique Sales Andrade ◽  
Diego Magno Assis ◽  
Rosana Helena Vicente Pereira ◽  
Ana Cristina Gales ◽  
...  
Keyword(s):  
Species Identification ◽  
Burkholderia Cepacia ◽  
Clinical Isolates ◽  
Burkholderia Cepacia Complex ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms

scholarly journals Development and Validation of an In-House Library for Filamentous Fungi Identification by MALDI-TOF MS in a Clinical Laboratory in Medellin (Colombia)

2020 ◽  
Vol 8 (9) ◽  
pp. 1362
Author(s):  
Juan C. Gómez-Velásquez ◽  
Natalia Loaiza-Díaz ◽  
Gilma Norela Hernández ◽  
Nelson Lima ◽  
Ana C. Mesa-Arango
Keyword(s):  
Filamentous Fungi ◽  
Clinical Laboratory ◽  
Species Level ◽  
Clinical Isolates ◽  
Correct Identification ◽  
Maldi Tof Ms ◽  
Genus Level ◽  
Maldi Tof ◽  
Fungal Identification ◽  
Tof Ms

Identification of filamentous fungi by conventional phenotypic methods are time-consuming, and a correct identification at the species level is prone to errors. Therefore, a more accurate and faster time-to-results, and cost-effective technique, is required, such as the Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS). In this study, we describe the development of an in-house spectra library for the identification of filamentous fungi frequently isolated from patients with infections. An in-house spectra library was constructed using 14 reference strains grown in solid medium. Clinical isolates were identified either by the in-house spectra library or the Biotyper commercial library from Bruker Daltonics. Fungal identification was carried following the Biotyper’s established scores: ≤1.699: not reliably identified (NRI); 1.700–1.999: genus-level; ≥2.000: species-level. Clinical isolates were identified, with the in-house library, at species- and genus-level at 88.70% (55) and 3.22% (2), respectively. While 4.80% (3) was NRI and 3.22% (2) was discrepant concerning sequencing. On the contrary, identification up to species and genus-level with the commercial library was 44.44% (16) and 22.22% (8), respectively. NRI and the discrepancy was 30.55% (11) and 2.77% (1), respectively. For the reaming 26 isolates, 16 from Neoscytalidium dimidiatum and 10 from Sporothrix spp., respectively, the absence of spectrum and the specific spectra within the Sporothrix complex in the commercial library resulted in the inability to obtain an identification. In conclusion, the current results advocate the importance that each clinical microbiological laboratory needs to develop an ad hoc library associated with the MALDI-TOF MS fungal identification to overcome the limitations of the available commercial libraries.

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