Species identification of Streptococcus bovis group isolates causing bacteremia: a comparison of two MALDI-TOF MS systems

2017 ◽  
Vol 88 (1) ◽  
pp. 23-25 ◽  
Author(s):  
Charlotte N. Agergaard ◽  
Elisa Knudsen ◽  
Rimtas Dargis ◽  
Xiaohui C. Nielsen ◽  
Jens J. Christensen ◽  
...  
Keyword(s):  
Species Identification ◽  
Streptococcus Bovis ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms

scholarly journals Effect of trapping method on species identification of phlebotomine sandflies by MALDI-TOF MS protein profiling

2018 ◽  
Vol 32 (3) ◽  
pp. 388-392 ◽  
Author(s):  
P. Halada ◽  
K. Hlavackova ◽  
J. Risueño ◽  
E. Berriatua ◽  
P. Volf ◽  
...  
Keyword(s):  
Species Identification ◽  
Protein Profiling ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Phlebotomine Sandflies ◽  
Trapping Method ◽  
Tof Ms

scholarly journals Species identification of enterobacteria strains by means of MALDI-TOF MS

2018 ◽  
pp. 110-113
Author(s):  
D.A. Vasiliev ◽  
◽  
N.A. Feoktistova ◽  
A.V. Mastilenko ◽  
E.V. Suldina ◽  
...  
Keyword(s):  
Species Identification ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms

scholarly journals Novel attempt at discrimination of a bullet-shaped siphonophore (Family Diphyidae) using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-ToF MS)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nayeon Park ◽  
Jisu Yeom ◽  
Raehyuk Jeong ◽  
Wonchoel Lee
Keyword(s):  
Species Identification ◽  
Morphological Characteristics ◽  
Kuroshio Current ◽  
Northwest Pacific ◽  
Maldi Tof Ms ◽  
Protein Mass ◽  
Maldi Tof ◽  
Morphological Findings ◽  
Flight Mass Spectrometry ◽  
Tof Ms

AbstractOne major difficulty in identifying the gelatinous bodied bullet-shaped Siphonophore, Diphyids, is that their shape is deformed following ethanol fixation. Ethanol often is preferred over other fixatives, since samples fixed in ethanol can be used for molecular studies that can supplement morphological findings. To overcome this problem, we obtained protein mass spectra of ten species of Diphyidae found in the waters of the Kuroshio Current (Northwest Pacific and South Coast of South Korea) to test whether MALDI-ToF MS could be used as a methodology for species identification. In addition, a number of morphological characteristics that can be used with ethanol-treated samples was summarized. Concatenated phylogenetic analysis was also performed to determine the phylogenetic relationship by obtaining partial sequences of four genes (mtCOI, 16S rRNA, 18S rRNA, and ITS regions). Based on our integrative analysis, MALDI-ToF MS was evaluated as a potentially fast, inexpensive, and accurate tool for species identification along with conventional morphological and DNA barcoding for Diphyidae.

scholarly journals Short Incubation of Positive Blood Cultures on Solid Media for Species Identification by MALDI-TOF MS: Which Agar Is the Fastest?

2021 ◽  
Author(s):  
Neele J. Froböse ◽  
Evgeny A. Idelevich ◽  
Frieder Schaumburg
Keyword(s):  
Mass Spectrometry ◽  
Species Identification ◽  
Susceptibility Testing ◽  
Solid Medium ◽  
Blood Cultures ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Solid Media ◽  
Laboratory Results ◽  
Tof Ms

When blood cultures are flagged as positive, they are incubated on solid media to produce enough biomass of the bacterium for identification and susceptibility testing. Rapid turnaround times for laboratory results could save lives, and we wanted to assess which solid medium is best to shorten the time to species identification using MALDI-TOF mass spectrometry.

scholarly journals Identification of Nocardia species using Autof MS 1000 and Bruker MALDI-TOF MS systems: A comparison

2021 ◽  
Author(s):  
Bing Ma ◽  
Yunqi Tian ◽  
Yungang Han ◽  
Lifang Ban ◽  
Junwen Yang ◽  
...  
Keyword(s):  
Species Identification ◽  
Protein Extraction ◽  
Reference Method ◽  
Invasive Disease ◽  
Species Level ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
Significant Difference ◽  
Tof Ms

ABSTRACTNocardia is an important cause of clinically invasive disease, but for most clinical laboratories, identification of these isolates to the species level is challenging. Recently, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been widely used for identification of most bacterial and fungal isolates. In this multicenter study, we evaluated the identification of Nocardia isolates using Autof MS1000 and Bruker Biotyper. A total of 86 non-duplicate Nocardia isolates from 7 hospital laboratories were evaluated. Further, we carried out sequence analysis of 16S rRNA, gyrB, secA1, hsp65, and rpoB genes as a reference method for Nocardia species identification. The 86 isolates were directly spotted on the target plate and plate protein extraction was performed. Data were analyzed by SPSS 19.0. In total, 72 (83.7%) strains (score ≥ 9.0) and 70 (81.4%) strains (score ≥ 2.0) were correctly identified by the Autof MS1000 and Bruker Biotyper systems, respectively, at the species level. There was no significant difference (P > 0.05) between the two systems using the same protein extraction method. In conclusion, the Autof MS 1000 and Bruker MALDI-TOF systems showed no difference in identification of Nocardia spp. to the species level and could meet the most important clinical requirement for species identification.

scholarly journals Rapid and cost-effective identification of Bartonella species using mass spectrometry

2009 ◽  
Vol 58 (9) ◽  
pp. 1154-1159 ◽  
Author(s):  
Pierre-Edouard Fournier ◽  
Carine Couderc ◽  
Sylvain Buffet ◽  
Christophe Flaudrops ◽  
Didier Raoult
Keyword(s):  
Mass Spectrometry ◽  
Species Identification ◽  
Chemical Reactivity ◽  
Bacterial Species ◽  
Cost Effective ◽  
Molecular Techniques ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Flight Mass Spectrometry ◽  
Tof Ms

Bacteria of the genus Bartonella are emerging zoonotic bacteria recognized in a variety of human diseases. Due to their poor chemical reactivity, these fastidious bacteria are poorly characterized using routine phenotypic laboratory tests. Identification is usually achieved using molecular techniques that are time-consuming, expensive and technically demanding. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has emerged as a new technique for bacterial species identification. This study evaluated the use of MALDI-TOF MS for rapid genus and species identification of Bartonella species. Reference strains representing 17 recognized Bartonella species were studied. For each species, MS spectra for four colonies were analysed. The consensus spectrum obtained for each species was unique among spectra obtained for 2843 bacteria within the Bruker database, including 109 alphaproteobacteria. Thirty-nine additional blind-coded Bartonella strains were correctly identified at the species level, including 36 with a significant score. Altogether, these data demonstrate that MS is an accurate and reproducible tool for rapid and inexpensive identification of Bartonella species.

scholarly journals Species identification within Acinetobacter calcoaceticus–baumannii complex using MALDI-TOF MS

2015 ◽  
Vol 118 ◽  
pp. 128-132 ◽  
Author(s):  
Benjamin E.W. Toh ◽  
David L. Paterson ◽  
Witchuda Kamolvit ◽  
Hosam Zowawi ◽  
David Kvaskoff ◽  
...  
Keyword(s):  
Species Identification ◽  
Acinetobacter Calcoaceticus ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms

scholarly journals New assessment of Anopheles vector species identification using MALDI-TOF MS

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Cécile Nabet ◽  
Abdoulaye K. Kone ◽  
Abdoulaye K. Dia ◽  
Moussa Sylla ◽  
Magali Gautier ◽  
...  
Keyword(s):  
Species Identification ◽  
Frozen Storage ◽  
Anopheles Funestus ◽  
Control Programme ◽  
The Body ◽  
Malaria Vector Control ◽  
Body Parts ◽  
Maldi Tof Ms ◽  
Maldi Tof ◽  
Tof Ms

Abstract Background Anopheles species identification is essential for an effective malaria vector control programme. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) has been developed to identify adult Anopheles species, using the legs or the cephalothorax. The protein repertoire from arthropods can vary according to compartment, but there is no general consensus regarding the anatomic part to be used. Methods To determine the body part of the Anopheles mosquitoes best suited for the identification of field specimens, a mass spectral library was generated with head, thorax with wings and legs of Anopheles gambiae, Anopheles arabiensis and Anopheles funestus obtained from reference centres. The MSL was evaluated using two independent panels of 52 and 40 An. gambiae field-collected in Mali and Guinea, respectively. Geographic variability was also tested using the panel from Mali and several databases containing added specimens from Mali and Senegal. Results Using the head and a database without specimens from the same field collection, the proportion of interpretable and correct identifications was significantly higher than using the other body parts at a threshold value of 1.7 (p < 0.0001). The thorax of engorged specimens was negatively impacted by the blood meal after frozen storage. The addition of specimens from Mali into the database significantly improved the results of Mali panel (p < 0.0001), which became comparable between head and legs. With higher identification scores, the using of the head will allow to decrease the number of technical replicates of protein extract per specimen, which represents a significant improvement for routine use of MALDI-TOF MS. Conclusions The using of the head of Anopheles may improve the performance of MALDI-TOF MS. Region-specific mass spectrum databases will have to be produced. Further research is needed to improve the standardization in order to share online spectral databases.

scholarly journals Factors Associated With MALDI-TOF Mass Spectral Quality of Species Identification in Clinical Routine Diagnostics

2021 ◽  
Vol 11 ◽  
Author(s):  
Aline Cuénod ◽  
Frédéric Foucault ◽  
Valentin Pflüger ◽  
Adrian Egli
Keyword(s):  
Species Identification ◽  
Burkholderia Cepacia ◽  
Bacterial Species ◽  
Clinical Diagnostics ◽  
Spectral Quality ◽  
Bacterial Colony ◽  
Maldi Tof Ms ◽  
Mass Spectral ◽  
Maldi Tof ◽  
Tof Ms

BackgroundAn accurate and timely identification of bacterial species is critical in clinical diagnostics. Species identification allows a potential first adaptation of empiric antibiotic treatments before the resistance profile is available. Matrix assisted Laser Desorption Ionization Time of Flight mass spectrometry (MALDI-TOF MS) is a widely used method for bacterial species identification. However, important challenges in species identification remain. These arise from (i) incomplete databases, (ii) close relatedness of species of interest, and (iii) spectral quality, which is currently vaguely defined.MethodsWe selected 47 clinically relevant bacterial isolates from 39 species, which can be challenging to identify by MALDI-TOF MS. We measured these isolates under various analytical conditions on two MALDI-TOF MS systems. First, we identified spectral features, which were associated with correct species identification in three different databases. Considering these features, we then systematically compared spectra produced with three different sample preparation protocols. In addition, we varied quantities of bacterial colony material applied and bacterial colony age.ResultsWe identified (i) the number of ribosomal marker peaks detected, (ii) the median relative intensity of ribosomal marker peaks, (iii) the sum of the intensity of all detected peaks, (iv) a high measurement precision, and (v) reproducibility of peaks to act as good proxies of spectral quality. We found that using formic acid, measuring bacterial colonies at a young age, and frequently calibrating the MALDI-TOF MS device increase mass spectral quality. We further observed significant differences in spectral quality between different bacterial taxa and optimal measurement conditions vary per taxon.ConclusionWe identified and applied quality measures for MALDI-TOF MS and optimized spectral quality in routine settings. Phylogenetic marker peaks can be reproducibly detected and provide an increased resolution and the ability to distinguish between challenging species such as those within the Enterobacter cloacae complex, Burkholderia cepacia complex, or viridans streptococci.

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