scholarly journals In Vitro Susceptibility of Fusarium to Isavuconazole

2019 ◽  
Vol 64 (2) ◽  
Author(s):  
A. Broutin ◽  
J. Bigot ◽  
Y. Senghor ◽  
A. Moreno-Sabater ◽  
J. Guitard ◽  
...  
Keyword(s):  
Laser Desorption ◽  
Laser Desorption Ionization ◽  
In Vitro Susceptibility ◽  
Ionization Time ◽  
Valuable Alternative ◽  
Flight Mass Spectrometry ◽  
Microdilution Method ◽  
Species Complexes ◽  
Broth Microdilution Method

ABSTRACT To evaluate the in vitro susceptibility of Fusarium to isavuconazole, 75 clinical isolates were identified using matrix-assisted laser desorption ionization–time of flight mass spectrometry and then tested with a broth microdilution method (EUCAST) and the gradient concentration strip (GCS) technique. The activity of isavuconazole overall was shown to be limited, with an MIC50 of >16 μg/ml, without significant differences between the species complexes. The categorical agreement between GCS and EUCAST was 97.4% to 100%, making the GCS as a valuable alternative.

O-glycans on human high endothelial CD34 putatively participating in L-selectin recognition

Blood ◽  
2002 ◽  
Vol 99 (7) ◽  
pp. 2609-2611 ◽  
Author(s):  
Tero Satomaa ◽  
Ossi Renkonen ◽  
Jari Helin ◽  
Juha Kirveskari ◽  
Antti Mäkitie ◽  
...  
Keyword(s):  
Laser Desorption ◽  
Sialyl Lewis X ◽  
Laser Desorption Ionization ◽  
Ionization Time ◽  
Flight Mass Spectrometry ◽  
Sialyl Lewis ◽  
Candidate Structure ◽  
Selectin Ligands ◽  
Matrix Assisted Laser

Leukocyte traffic into lymph nodes and sites of inflammation is guided by L-selectin. Experiments performed in vitro and with gene-deleted mice suggest that CD34 recognizes L-selectin if decorated by 6-sulfo sialyl Lewis x (sLex) saccharides and the MECA-79 epitope. However, very little is known about glycosylation of human L-selectin ligands. We report here on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) profiles of N- and O-linked oligosaccharide fractions from human tonsillar endothelial CD34. All detected O-glycans were sialylated; some were also monosulfated or monosulfated and monofucosylated. If a given CD34-glycan may carry all requirements for L-selectin recognition, that is, both 6-sulfo-sLex and MECA-79 epitopes, only one O-glycan fraction, O-9, SA2Hex3HexNAc3- Fuc1(SO3)1, meets the criteria. A candidate structure is SAα2-3Galβ1-4(Fucα1-3)(6-sulfo)GlcNAcβ1-3Galβ1-3(SAα2-3Galβ1-4GlcNAcβ1-6)GalNAc. However, if sulfo sLex glycans are supplemented with separate sulfated, nonfucosylated O-glycans, saccharides in O-6, O-8, or O-9, putatively carrying MECA-79 epitopes, could form multiglycan binding epitopes for L-selectin.

scholarly journals Identification of a Protein That Inactivates the Competence-Stimulating Peptide of Streptococcus pneumoniae

2002 ◽  
Vol 184 (2) ◽  
pp. 610-613 ◽  
Author(s):  
Mathieu Bergé ◽  
Hanno Langen ◽  
Jean-Pierre Claverys ◽  
Bernard Martin
Keyword(s):  
Streptococcus Pneumoniae ◽  
Laser Desorption ◽  
Physiological Property ◽  
Laser Desorption Ionization ◽  
Treatment Results ◽  
Ionization Time ◽  
Flight Mass Spectrometry ◽  
Licl Treatment

ABSTRACT Competence for genetic transformation of Streptococcus pneumoniae is a transient physiological property inducible by a competence-stimulating peptide (CSP). A 68-kDa CSP-inactivating protein was previously obtained following lithium chloride (LiCl) extraction. By the same protocol, a CSP-inactivating protein was purified and identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry as an endopeptidase, PepO. Analysis of a pepO mutant provided no support for the hypothesis that PepO participates in competence regulation. To reconcile in vitro and in vivo data, we suggest that LiCl treatment results in the release of intracellular molecules, including PepO.

scholarly journals Use of Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry for Identification of Molds of the Fusarium Genus

2014 ◽  
Vol 53 (2) ◽  
pp. 465-476 ◽  
Author(s):  
David Triest ◽  
Dirk Stubbe ◽  
Koen De Cremer ◽  
Denis Piérard ◽  
Anne-Cécile Normand ◽  
...  
Keyword(s):  
Species Complex ◽  
Laser Desorption ◽  
Laser Desorption Ionization ◽  
Ionization Time ◽  
Content Type ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
Species Complexes ◽  
Tof Ms

The rates of infection withFusariummolds are increasing, and a diverse number ofFusariumspp. belonging to different species complexes can cause infection. Conventional species identification in the clinical laboratory is time-consuming and prone to errors. We therefore evaluated whether matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) is a useful alternative. The 289Fusariumstrains from the Belgian Coordinated Collections of Microorganisms (BCCM)/Institute of Hygiene and Epidemiology Mycology (IHEM) culture collection with validated sequence-based identities and comprising 40 species were used in this study. An identification strategy was developed, applying a standardized MALDI-TOF MS assay and an in-house reference spectrum database.In vitroantifungal testing was performed to assess important differences in susceptibility between clinically relevant species/species complexes. We observed that no incorrect species complex identifications were made by MALDI-TOF MS, and 82.8% of the identifications were correct to the species level. This success rate was increased to 91% by lowering the cutoff for identification. Although the identification of the correct species complex member was not always guaranteed, antifungal susceptibility testing showed that discriminating betweenFusariumspecies complexes can be important for treatment but is not necessarily required between members of a species complex. With this perspective, someFusariumspecies complexes with closely related members can be considered as a whole, increasing the success rate of correct identifications to 97%. The application of our user-friendly MALDI-TOF MS identification approach resulted in a dramatic improvement in both time and accuracy compared to identification with the conventional method. A proof of principle of our MALDI-TOF MS approach in the clinical setting using recently isolatedFusariumstrains demonstrated its validity.

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