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Novák J, Schug KA, Havlíček V. Quantitation of small molecules from liquid chromatography-mass spectrometric accurate mass datasets using CycloBranch. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2023; 29:102-110. [PMID: 37000628 DOI: 10.1177/14690667231164766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Gaussian and exponentially modified Gaussian functions were incorporated into integrating algorithms used by an open-source, cross-platform tool called CycloBranch. The quantitation is demonstrated on bacterial pyoverdines separated by fine isotope features. Using our algorithm, we can separate the m/z values 694.25802 and 694.26731 (a 0.009 Da difference), where the former belongs to the most intense peak of pyoverdine D (PvdD), and the latter to the second most intense peak of pyoverdine E (PvdE) in the respective isotopic clusters of [M + Fe-H]2+ ions. The areas under chromatographic curves of standards were analyzed for the limit of detection (LOD), limit of quantitation (LOQ), and regression coefficient calculations. The quantitative module returned a LOD and LOQ of 1.4 and 4.3 ng/mL, respectively, for both PvdD and PvdE in human urine. If present and detected in mass spectra, the intensities of user-defined [M + H]+, [M + Na]+, [M + K]+, [M + Fe-H]2+, or other ion types, can be accumulated and used for quantitation. The quantitation result is returned by CycloBranch in seconds or minutes, contrary to an hours-long manual approach, prone to user-born errors originating from necessary copying among various software environments. Native Bruker, Waters, Thermo, txt, mgf, mzML, and mzXML data formats are supported in CycloBranch, which is freely available at https://ms.biomed.cas.cz/cyclobranch.
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Affiliation(s)
- Jiří Novák
- Institute of Microbiology, 48311Czech Academy of Sciences, Prague, Czech Republic
- Faculty of Information Technology, Czech Technical University in Prague, Prague, Czech Republic
| | - Kevin A Schug
- Department of Chemistry and Biochemistry, The University of Texas Arlington, Arlington, TX, USA
| | - Vladimír Havlíček
- Institute of Microbiology, 48311Czech Academy of Sciences, Prague, Czech Republic
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Přívratský J, Novák J. MassSpecBlocks: a web-based tool to create building blocks and sequences of nonribosomal peptides and polyketides for tandem mass spectra analysis. J Cheminform 2021; 13:51. [PMID: 34233741 PMCID: PMC8265115 DOI: 10.1186/s13321-021-00530-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 06/30/2021] [Indexed: 11/16/2022] Open
Abstract
Nonribosomal peptides and polyketides are natural products commonly synthesized by microorganisms. They are widely used in medicine, agriculture, environmental protection, and other fields. The structures of natural products are often analyzed by high-resolution tandem mass spectrometry, which becomes more popular with its increasing availability. However, the characterization of nonribosomal peptides and polyketides from tandem mass spectra is a nontrivial task because they are composed of many uncommon building blocks in addition to proteinogenic amino acids. Moreover, many of them have cyclic and branch-cyclic structures. Here, we introduce MassSpecBlocks – an open-source and web-based tool that converts the input chemical structures in SMILES format into sequences of building blocks. The structures can be searched in public databases PubChem, ChemSpider, ChEBI, NP Atlas, COCONUT, and Norine and edited in a user-friendly graphical interface. Although MassSpecBlocks can serve as a stand-alone database, our primary goal was to enable easy construction of custom sequence and building block databases, which can be used to annotate mass spectra in CycloBranch software. CycloBranch is an open-source, cross-platform, and stand-alone tool that we recently released for annotating spectra of linear, cyclic, branched, and branch-cyclic nonribosomal peptides and polyketide siderophores. The sequences and building blocks created in MassSpecBlocks can be easily exported into a plain text format used by CycloBranch. MassSpecBlocks is available online or can be installed entirely offline. It offers a REST API to cooperate with other tools. ![]()
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Affiliation(s)
- Jan Přívratský
- Faculty of Information Technology, Czech Technical University in Prague, Thákurova 9, 160 00, Prague, Czech Republic
| | - Jiří Novák
- Faculty of Information Technology, Czech Technical University in Prague, Thákurova 9, 160 00, Prague, Czech Republic. .,Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague, Czech Republic.
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Mácha H, Marešová H, Juříková T, Švecová M, Benada O, Škríba A, Baránek M, Novotný Č, Palyzová A. Killing Effect of Bacillus Velezensis FZB42 on a Xanthomonas Campestris pv. Campestris (Xcc) Strain Newly Isolated from Cabbage Brassica Oleracea Convar. Capitata (L.): A Metabolomic Study. Microorganisms 2021; 9:microorganisms9071410. [PMID: 34210064 PMCID: PMC8303752 DOI: 10.3390/microorganisms9071410] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/22/2021] [Accepted: 06/25/2021] [Indexed: 11/16/2022] Open
Abstract
The potential use of Bacillus velezensis FZB42 for biological control of various phytopathogens has been documented over the past few years, but its antagonistic interactions with xanthomonads has not been studied in detail. Novel aspects in this study consist of close observation of the death of Xanthomonas campestris pv. campestris cells in a co-culture with B. velezensis FZB42, and quantification of lipopeptides and a siderophore, bacillibactin, involved in the killing process. A new robust Xcc-SU isolate tolerating high concentrations of ferric ions was used. In a co-culture with the antagonist, the population of Xcc-SU was entirely destroyed within 24–48 h, depending on the number of antagonist cells used for inoculation. No inhibitory effect of Xcc-SU on B. velezensis was observed. Bacillibactin and lipopeptides (surfactin, fengycin, and bacillomycin) were present in the co-culture and the monoculture of B. velezensis. Except for bacillibactin, the maximum contents of lipopeptides were higher in the antagonist monoculture compared with the co-culture. Scanning electron microscopy showed that the death of Xcc-SU bacteria in co-culture was caused by cell lysis, leading to an enhanced occurrence of distorted cells and cell ghosts. Analysis by mass spectrometry showed four significant compounds, bacillibactin, surfactin, fengycin, and bacillomycin D amongst a total of 24 different forms detected in the co-culture supernatant: Different forms of surfactin and fengycin with variations in their side-chain length were also detected. These results demonstrate the ability of B. velezensis FZB42 to act as a potent antagonistic strain against Xcc.
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Affiliation(s)
- Hynek Mácha
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic; (H.M.); (H.M.); (T.J.); (M.Š.); (O.B.); (A.Š.); (Č.N.)
- Department of Analytical Chemistry, Faculty of Science, Palacký University, 17. Listopadu 12, 771 46 Olomouc, Czech Republic
| | - Helena Marešová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic; (H.M.); (H.M.); (T.J.); (M.Š.); (O.B.); (A.Š.); (Č.N.)
| | - Tereza Juříková
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic; (H.M.); (H.M.); (T.J.); (M.Š.); (O.B.); (A.Š.); (Č.N.)
| | - Magdaléna Švecová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic; (H.M.); (H.M.); (T.J.); (M.Š.); (O.B.); (A.Š.); (Č.N.)
| | - Oldřich Benada
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic; (H.M.); (H.M.); (T.J.); (M.Š.); (O.B.); (A.Š.); (Č.N.)
| | - Anton Škríba
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic; (H.M.); (H.M.); (T.J.); (M.Š.); (O.B.); (A.Š.); (Č.N.)
| | - Miroslav Baránek
- Faculty of Horticulture-Mendeleum, Mendel University, Valtická 337, 69144 Lednice, Czech Republic;
| | - Čeněk Novotný
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic; (H.M.); (H.M.); (T.J.); (M.Š.); (O.B.); (A.Š.); (Č.N.)
| | - Andrea Palyzová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic; (H.M.); (H.M.); (T.J.); (M.Š.); (O.B.); (A.Š.); (Č.N.)
- Correspondence: ; Tel.: +420-241062617
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Covas C, Almeida B, Esteves AC, Lourenço J, Domingues P, Caetano T, Mendo S. Peptone from casein, an antagonist of nonribosomal peptide synthesis: a case study of pedopeptins produced by Pedobacter lusitanus NL19. N Biotechnol 2020; 60:62-71. [PMID: 32891869 DOI: 10.1016/j.nbt.2020.07.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/20/2020] [Accepted: 07/25/2020] [Indexed: 01/30/2023]
Abstract
Novel natural products are urgently needed to address the worldwide incidence of bacterial resistance to antibiotics. Extreme environments are a major source of novel compounds with unusual chemical structures. Pedobacter lusitanus NL19 is a new bacterial species that was isolated from one such environment and which produces compounds with potent activity against relevant microorganisms in the clinical, food, veterinary and aquaculture areas. The production of antimicrobials by P. lusitanus NL19 was identified in tryptic soy agar (TSA), but not in its equivalent broth (TSB). It was observed that in TSB medium a high concentration of casein peptone (PC) repressed the production of antibacterial compounds. HPLC, MS and MS/MS spectra with de novo sequencing revealed that the bioactivity of P. lusitanus NL19 was due to the production of pedopeptins. Hence, biosynthesis of pedopeptins is inhibited by high concentrations of PC in the broth medium. Furthermore, a nonribosomal peptide synthetase (NRPS) gene cluster was identified in the genome of NL19 encoding the biosynthesis of the peptides. qPCR analysis confirmed that the transcription of these genes is repressed in cells cultivated in high concentrations of PC. It is shown that pedopeptins are nonribosomal peptides with a broad-spectrum activity, including against Gram-positive and Gram-negative bacteria and yeasts.
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Affiliation(s)
- Cláudia Covas
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal
| | - Beatriz Almeida
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal
| | - Ana Cristina Esteves
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal; Universidade Católica Portuguesa, Faculty of Dental Medicine, Center for Interdisciplinary Research in Health (CIIS), Portugal
| | - Joana Lourenço
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal
| | - Pedro Domingues
- Mass Spectrometry Centre and LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Aveiro, 3810-193, Portugal
| | - Tânia Caetano
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal
| | - Sónia Mendo
- CESAM and Department of Biology, University of Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal.
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Stoszko M, Al-Hatmi AMS, Skriba A, Roling M, Ne E, Crespo R, Mueller YM, Najafzadeh MJ, Kang J, Ptackova R, LeMasters E, Biswas P, Bertoldi A, Kan TW, de Crignis E, Sulc M, Lebbink JH, Rokx C, Verbon A, van Ijcken W, Katsikis PD, Palstra RJ, Havlicek V, de Hoog S, Mahmoudi T. Gliotoxin, identified from a screen of fungal metabolites, disrupts 7SK snRNP, releases P-TEFb, and reverses HIV-1 latency. SCIENCE ADVANCES 2020; 6:eaba6617. [PMID: 32851167 PMCID: PMC7423394 DOI: 10.1126/sciadv.aba6617] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 07/01/2020] [Indexed: 05/16/2023]
Abstract
A leading pharmacological strategy toward HIV cure requires "shock" or activation of HIV gene expression in latently infected cells with latency reversal agents (LRAs) followed by their subsequent clearance. In a screen for novel LRAs, we used fungal secondary metabolites as a source of bioactive molecules. Using orthogonal mass spectrometry (MS) coupled to latency reversal bioassays, we identified gliotoxin (GTX) as a novel LRA. GTX significantly induced HIV-1 gene expression in latent ex vivo infected primary cells and in CD4+ T cells from all aviremic HIV-1+ participants. RNA sequencing identified 7SK RNA, the scaffold of the positive transcription elongation factor b (P-TEFb) inhibitory 7SK small nuclear ribonucleoprotein (snRNP) complex, to be significantly reduced upon GTX treatment of CD4+ T cells. GTX directly disrupted 7SK snRNP by targeting La-related protein 7 (LARP7), releasing active P-TEFb, which phosphorylated RNA polymerase II (Pol II) C-terminal domain (CTD), inducing HIV transcription.
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Affiliation(s)
- Mateusz Stoszko
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Abdullah M. S. Al-Hatmi
- Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands
- Center of Expertise in Mycology of Radboud UMC/CWZ, Nijmegen, Netherlands
- Ministry of Health, Directorate General of Health Services, Ibri, Oman
| | - Anton Skriba
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, CZ 14220 Prague 4, Czech Republic
| | - Michael Roling
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Enrico Ne
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Raquel Crespo
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Yvonne M. Mueller
- Department of Immunology, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Mohammad Javad Najafzadeh
- Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands
- Department of Parasitology and Mycology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Joyce Kang
- Key Laboratory of Environmental Pollution Monitoring/Disease Control, Ministry of Education and Guizhou Talent Base of Microbes and Human Health, School of Basic Medicine, Guizhou Medical University, Guiyang 550025, P. R. China
| | - Renata Ptackova
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, CZ 14220 Prague 4, Czech Republic
| | - Elizabeth LeMasters
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Pritha Biswas
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Alessia Bertoldi
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
- Microbiology Section, Department of Experimental, Diagnostic and Specialty Medicine, School of Medicine, University of Bologna, Bologna, Italy
| | - Tsung Wai Kan
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Elisa de Crignis
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Miroslav Sulc
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, CZ 14220 Prague 4, Czech Republic
| | - Joyce H.G. Lebbink
- Departments of Molecular Genetics and Radiation Oncology, Erasmus University Medical Center, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Casper Rokx
- Department of Internal Medicine, Section of Infectious Diseases, Erasmus University Medical Center, PO Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Annelies Verbon
- Department of Internal Medicine, Section of Infectious Diseases, Erasmus University Medical Center, PO Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Wilfred van Ijcken
- Erasmus MC Genomics Core Facility, Department of Cell Biology, Erasmus University Medical Center, PO Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Peter D. Katsikis
- Department of Immunology, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Robert-Jan Palstra
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Vladimir Havlicek
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, CZ 14220 Prague 4, Czech Republic
| | - Sybren de Hoog
- Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands
- Center of Expertise in Mycology of Radboud UMC/CWZ, Nijmegen, Netherlands
| | - Tokameh Mahmoudi
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
- Corresponding author.
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Novák J, Škríba A, Havlíček V. CycloBranch 2: Molecular Formula Annotations Applied to imzML Data Sets in Bimodal Fusion and LC-MS Data Files. Anal Chem 2020; 92:6844-6849. [PMID: 32338876 DOI: 10.1021/acs.analchem.0c00170] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Natural product chemistry, microbiology, and food, human, and plant metabolomics represent a few sources of complex metabolomics data generated by mass spectrometry. Among the medley of software tools used to handle these data sets, no universal tool can qualitatively, quantitatively, or statistically address major biological questions or tasks. CycloBranch 2, an open and platform-free software, at least now provides the de novo generation of molecular formulas of unknown compounds in both liquid chromatography/mass spectrometry and mass spectrometry imaging datafiles. For imaging files, this database-free approach was documented in the bimodal image fusion and characterization of three small molecules, including metallophores. The fine isotope ratio data filtering step distinguished 34S/13C2 and 41K/13C2 features. The standalone software package is implemented in C++ and can be downloaded from https://ms.biomed.cas.cz/cyclobranch/ and used under GNU General Public License.
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Affiliation(s)
- Jiří Novák
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Anton Škríba
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Vladimír Havlíček
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
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Palyzová A, Marešová H, Novák J, Zahradník J, Řezanka T. Effect of the anti-inflammatory drug diclofenac on lipid composition of bacterial strain Raoultella sp. KDF8. Folia Microbiol (Praha) 2020; 65:763-773. [PMID: 32318987 DOI: 10.1007/s12223-020-00790-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 04/08/2020] [Indexed: 01/18/2023]
Abstract
The strain Raoultella sp. KDF8 was cultivated on three sources of carbon and energy, glycerol, ethanol and diclofenac, for periods of time ranging from 24 to 72 h. Using thin-layer chromatography, nine classes of phospholipids were detected and the amount of phosphatidylethanolamine (PtdEtn) decreased with increasing cultivation time. Conversely, the ratio of phospholipids having three or four acyls (acyl-phosphatidylglycerol (APtdGro), N-acyl-PtdEtn (NAPtdEtn) and cardiolipin (Ptd2Gro) increased during cultivation. GC-MS analysis showed that the percentage of fatty acids containing a cyclopropane ring increased almost tenfold whereas the amount of fatty acids bearing even-numbered chains dropped to less than one-third after 24 h and 72 h in cultures on glycerol and diclofenac, respectively. Shotgun analysis showed significant changes in the representation of molecular species of phospholipids. For instance, there was a 36-fold change in the ratio of 16:1/16:1/16:1-APtdGro to c17:0/c17:0/c17:0-APtdGro and a 12-fold ratio change for 16:1/16:1/16:1-NAPtdEtn to c17:0/c17:0/c17:0-NAPtdEtn; the Ptd2Gro ratio of 16:1 to c17:0 acids equalled 1750. Our results show that the bacteria overcome destabilization of the inner cytoplasmic cell membrane and a bacterial outer membrane by altering the geometric arrangement of acyl chains, i.e. switching from monounsaturated to cyclopropane fatty acids (16:1 versus c17:0).
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Affiliation(s)
- Andrea Palyzová
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Helena Marešová
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Jiří Novák
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Jiří Zahradník
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic
| | - Tomáš Řezanka
- Institute of Microbiology, Czech Academy of Sciences, Vídeňská 1083, 142 20, Prague 4, Czech Republic.
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Guerrero-Garzón JF, Zehl M, Schneider O, Rückert C, Busche T, Kalinowski J, Bredholt H, Zotchev SB. Streptomyces spp. From the Marine Sponge Antho dichotoma: Analyses of Secondary Metabolite Biosynthesis Gene Clusters and Some of Their Products. Front Microbiol 2020; 11:437. [PMID: 32256483 PMCID: PMC7093587 DOI: 10.3389/fmicb.2020.00437] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 03/02/2020] [Indexed: 01/25/2023] Open
Abstract
Actinomycete bacteria from marine environments represent a potential source for new antibiotics and anti-tumor drugs. Ten strains belonging to the genus Streptomyces isolated from the marine sponge Antho dichotoma collected at the bottom of the Trondheim fjord (Norway) were screened for antibiotic activity. Since only few isolates proved to be bioactive in the conditions tested, we decided to gain an insight into their biosynthetic potential using genome sequencing and analysis. Draft genomes were analyzed for the presence of secondary metabolite biosynthesis gene clusters (BGCs) using antiSMASH software. BGCs specifying both known and potentially novel secondary metabolites were identified, suggesting that these isolates might be sources for new bioactive compounds. The results of this analysis also implied horizontal transfer of several gene clusters between the studied isolates, which was especially evident for the lantibiotic- and thiopeptide-encoding BGCs. The latter implies the significance of particular secondary metabolites for the adaptation of Streptomyces to the spatially enclosed marine environments such as marine sponges. Two bioactive isolates, one showing activity against both yeast and Bacillus subtilis, and one only against yeast were analyzed in details, leading to the identification of cycloheximide, linearmycins, and echinomycins that are presumably responsible for the observed bioactivities.
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Affiliation(s)
| | - Martin Zehl
- Department of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria
| | - Olha Schneider
- Department of Pharmacognosy, University of Vienna, Vienna, Austria
| | | | - Tobias Busche
- Center for Biotechnology, Bielefeld University, Bielefeld, Germany
| | - Jörn Kalinowski
- Center for Biotechnology, Bielefeld University, Bielefeld, Germany
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Spraker JE, Luu GT, Sanchez LM. Imaging mass spectrometry for natural products discovery: a review of ionization methods. Nat Prod Rep 2020; 37:150-162. [PMID: 31364647 PMCID: PMC6992513 DOI: 10.1039/c9np00038k] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Covering: 2009-2019 Over the last decade, methods in imaging mass spectrometry (IMS) have progressively improved and diversified toward a variety of applications in natural products research. Because IMS allows for the spatial mapping of the production and distribution of biologically active molecules in situ, it facilitates phenotype and organelle driven discovery efforts. As practitioners of IMS for natural products discovery, we find one of the most important aspects of these experiments is the sample preparation and compatibility with different ionization sources that are available to a given researcher. As such, we have focused this mini review to cover types of ionization sources that have been used in natural products discovery applications and provided concrete examples of use for natural products discovery while discussing the advantages and limitations of each method. We aim for this article to serve as a resource to guide the broader natural product community interested in IMS toward the application/method that would best serve their natural product discovery needs given the sample and analyte(s) of interest. This mini review has been limited to applications using natural products and thus is not exhaustive of all possible ionization methods which have only been applied to image other types of samples such as mammalian tissues. Additionally, we briefly review how IMS has been coupled with other imaging platforms, such as microscopy, to enhance information outputs as well as offer our future perspectives on the incorporation of IMS in natural products discovery.
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Affiliation(s)
- Joseph E Spraker
- Hexagon Bio, 1505 Adams Drive, Suite A, Menlo Park, CA 94025, USA
| | - Gordon T Luu
- Department of Pharmaceutical Sciences, University of Illinois at Chicago, 833 S Wood St, Chicago, IL 60612, USA,
| | - Laura M Sanchez
- Department of Pharmaceutical Sciences, University of Illinois at Chicago, 833 S Wood St, Chicago, IL 60612, USA,
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10
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Kuo TH, Huang HC, Hsu CC. Mass spectrometry imaging guided molecular networking to expedite discovery and structural analysis of agarwood natural products. Anal Chim Acta 2019; 1080:95-103. [PMID: 31409479 DOI: 10.1016/j.aca.2019.05.070] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/27/2019] [Accepted: 05/28/2019] [Indexed: 02/04/2023]
Abstract
Structural analysis of biomolecules is essential to natural product discovery, especially for precious biomaterials such as agarwood. However, one of the greatest challenges to the characterization of natural products is the profound cost in time and manpower to the structural elucidation of these highly diverse compounds. Here, we demonstrate a multi-modal mass spectrometric strategy, integrating matrix-assisted laser desorption ionization (MALDI) mass spectrometry imaging (MSI) and mass spectral molecular networking, to uncover agarwood natural products of Aquilaria sinensis trees. A simple workflow for preparing wood sections for MALDI-MSI analysis was demonstrated. Notably, tens of natural products in the agarwood region in wood stem section of A. sinensis were spatially revealed by MALDI-MSI. For the first time, such a great number of plant specialized metabolites is obtained by a single wood section MSI. Guided by the spatially resolved features, mass spectral molecular networking was subsequently applied for structural analysis of the agarwood natural products, in which three major classes of 2-(2-phenylethyl)chromones and their analogues were putatively characterized. These results suggest an efficient strategy to the dereplication of plant natural products.
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Affiliation(s)
- Ting-Hao Kuo
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan.
| | - Hou-Chun Huang
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan.
| | - Cheng-Chih Hsu
- Department of Chemistry, National Taiwan University, Taipei, 10617, Taiwan.
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11
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Weiskirchen R, Weiskirchen S, Kim P, Winkler R. Software solutions for evaluation and visualization of laser ablation inductively coupled plasma mass spectrometry imaging (LA-ICP-MSI) data: a short overview. J Cheminform 2019; 11:16. [PMID: 30778692 PMCID: PMC6690067 DOI: 10.1186/s13321-019-0338-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 02/09/2019] [Indexed: 12/19/2022] Open
Abstract
Mass spectrometry imaging (MSI) using laser ablation (LA) inductively coupled plasma (ICP) is an innovative and exciting methodology to perform highly sensitive elemental analyses. LA-ICP-MSI of metals, trace elements or isotopes in tissues has been applied to a range of biological samples. Several LA-ICP-MSI studies have shown that metals have a highly compartmentalized distribution in some organs, which might be altered in consequence of genetic diseases, intoxication, or malnutrition. Although metal imaging by LA-ICP-MSI is an established methodology, potential pitfalls in the determination of metal concentrations might result from erroneous calibration, standardization, and normalization. In addition, for simple display of final imaging results, most LA-ICP-MSI users prefer to process their measurements by commercial processing software. Such programs typically visualize the regional metal differences in colorful and vivid imaging maps, but might not represent the actual signal densities correctly. There is a great abundance of such MSI data processing programs available differing in quality, usability, integrated features, workflow, reliability, system requirements, speed of data processing, and price. Some software packages contain a multitude of features which are superfluous for most users. In contrast, often only few data formats are used, in case of commercial programs even only the instrument provider’s own raw data format. Therefore, first time and average users are often confused and helpless in choosing the correct software for processing their data. Here we have briefly summarized software packages, data routines, macros, programming tools, scripts, algorithms, or self-written patches and updates for existing programs presently in use for mining LA-ICP-MSI data.![]()
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Affiliation(s)
- Ralf Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH University Hospital Aachen, 52074, Aachen, Germany.
| | - Sabine Weiskirchen
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH University Hospital Aachen, 52074, Aachen, Germany
| | - Philipp Kim
- Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH University Hospital Aachen, 52074, Aachen, Germany
| | - Robert Winkler
- Department of Biochemistry and Biotechnology, Center for Research and Advanced Studies (CINVESTAV) Irapuato, Km. 9.6 Libramiento Norte Carr. Irapuato-León, 36824, Irapuato, Gto., Mexico. .,Mass Spectrometry Group, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany.
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12
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Palyzová A, Svobodová K, Sokolová L, Novák J, Novotný Č. Metabolic profiling of Fusarium oxysporum f. sp. conglutinans race 2 in dual cultures with biocontrol agents Bacillus amyloliquefaciens, Pseudomonas aeruginosa, and Trichoderma harzianum. Folia Microbiol (Praha) 2019; 64:779-787. [PMID: 30746611 DOI: 10.1007/s12223-019-00690-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 02/05/2019] [Indexed: 11/26/2022]
Abstract
There are increasing efforts to identify biocontrol-active microbial metabolites in order to improve strategies for biocontrol of phytopathogens. In this work, Fusarium oxysporum f. sp. conglutinans was confronted with three different biocontrol agents: Trichoderma harzianum, Bacillus amyloliquefaciens, and Pseudomonas aeruginosa in dual culture bioassays. Metabolites produced during the microbial interactions were screened by a matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). T. harzianum exhibited the strongest inhibition of growth of F. oxysporum resulting in overlay of the pathogen colony with its mycelium. Recorded metabolite profiles suggested a direct attack of F. oxysporum mycelium by T. harzianum and B. amyloliquefaciens by means of membrane-attacking peptaibols and a set of antimicrobial lipopeptides and siderophores, respectively. The direct mode of the biocontrol activity of T. harzianum and B. amyloliquefaciens corresponded to their ability to suppress F. oxysporum production of mycotoxin beauvericin suggesting that this ability is not specific only for Trichoderma species. In the case of P. aeruginosa, siderophores pyoverdine E/D and two rhamnolipids were produced as major bacterial metabolites; the rhamnolipid production was blocked by F. oxysporum. The results showed that this type of biocontrol activity was the least effective against F. oxysporum. The effective application of MALDI-MS profiling to the screening of nonvolatile microbial metabolites produced during the interaction of the phytopathogen and the biocontrol microorganisms was demonstrated.
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Affiliation(s)
- Andrea Palyzová
- Institute of Microbiology of the CAS, v.v.i., Vídeňská 1083, 14220, Prague 4, Czech Republic
| | - Kateřina Svobodová
- Institute of Microbiology of the CAS, v.v.i., Vídeňská 1083, 14220, Prague 4, Czech Republic
| | - Lucie Sokolová
- Institute of Microbiology of the CAS, v.v.i., Vídeňská 1083, 14220, Prague 4, Czech Republic
| | - Jiří Novák
- Institute of Microbiology of the CAS, v.v.i., Vídeňská 1083, 14220, Prague 4, Czech Republic
| | - Čeněk Novotný
- Institute of Microbiology of the CAS, v.v.i., Vídeňská 1083, 14220, Prague 4, Czech Republic.
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13
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Pluhacek T, Skriba A, Novak J, Luptakova D, Havlicek V. Analysis of Microbial Siderophores by Mass Spectrometry. Methods Mol Biol 2019; 1996:131-153. [PMID: 31127553 DOI: 10.1007/978-1-4939-9488-5_12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Siderophores represent important microbial virulence factors and infection biomarkers. Their monitoring in fermentation broths, bodily fluids, and tissues should be reproducible. Similar isolation, characterization, and quantitation studies can often have conflicting results, and without proper documentation of sample collection, data processing, and analysis methods, it is difficult to reexamine the data and reconcile these differences. In this Springer Nature Protocol, we present the procedure optimized for ferricrocin/triacetylfusarinine C extraction from biological material as well as for tissue fixation and cryosectioning for optical microscopy and for both elemental and molecular mass spectrometry imaging. Special attention is paid to siderophore data mining from conventional and product ion mass spectra, liquid chromatography, and mass spectrometry imaging datasets, performed here by our free software called CycloBranch.
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Affiliation(s)
- Tomas Pluhacek
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Anton Skriba
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jiri Novak
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Dominika Luptakova
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Vladimir Havlicek
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic.
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14
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Novák J, Škríba A, Zápal J, Kuzma M, Havlíček V. CycloBranch: An open tool for fine isotope structures in conventional and product ion mass spectra. JOURNAL OF MASS SPECTROMETRY : JMS 2018; 53:1097-1103. [PMID: 30160332 DOI: 10.1002/jms.4285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 08/15/2018] [Accepted: 08/22/2018] [Indexed: 06/08/2023]
Abstract
Within the growing community of Fourier transform mass spectrometry users, the identification of fine isotope structure has become an indispensable method for molecular formula determination. In this work, the fine isotope envelopes for accessing the mutual ratio of 2 closely related pyoverdines in a mixture were used. Bacterial siderophores pyoverdines D and E cannot be easily separated via liquid chromatography-mass spectrometry because their structures differ in (de)amidation at the respective chromophore parts only. Their mutual ratio was determined in a mixture via nuclear magnetic resonance spectroscopy and semiquantitative mass spectrometry using our open-source software CycloBranch, which represents a genuine free tool supporting the determination of fine isotope structures in both conventional and product ion mass spectra. Native Bruker, Thermo, and Waters data formats are supported in addition to XML and plain text formats.
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Affiliation(s)
- Jiří Novák
- Institute of Microbiology of the CAS, v.v.i., Videnska 1083, 142 20, Prague 4, Czech Republic
| | - Anton Škríba
- Institute of Microbiology of the CAS, v.v.i., Videnska 1083, 142 20, Prague 4, Czech Republic
| | - Jakub Zápal
- Institute of Microbiology of the CAS, v.v.i., Videnska 1083, 142 20, Prague 4, Czech Republic
| | - Marek Kuzma
- Institute of Microbiology of the CAS, v.v.i., Videnska 1083, 142 20, Prague 4, Czech Republic
| | - Vladimír Havlíček
- Institute of Microbiology of the CAS, v.v.i., Videnska 1083, 142 20, Prague 4, Czech Republic
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15
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Luptakova D, Baciak L, Pluhacek T, Skriba A, Sediva B, Havlicek V, Juranek I. Membrane depolarization and aberrant lipid distributions in the neonatal rat brain following hypoxic-ischaemic insult. Sci Rep 2018; 8:6952. [PMID: 29725040 PMCID: PMC5934395 DOI: 10.1038/s41598-018-25088-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 04/13/2018] [Indexed: 12/12/2022] Open
Abstract
Neonatal hypoxic-ischaemic (HI) encephalopathy is among the most serious complications in neonatology. In the present study, we studied the immediate (0 hour), subacute (36 hours) and late (144 hours) responses of the neonatal brain to experimental HI insult in laboratory rats. At the striatal level, the mass spectrometry imaging revealed an aberrant plasma membrane distribution of Na+/K+ ions in the oedema-affected areas. The failure of the Na+/K+ gradients was also apparent in the magnetic resonance imaging measurements, demonstrating intracellular water accumulation during the acute phase of the HI insult. During the subacute phase, compared with the control brains, an incipient accumulation of an array of N-acylphosphatidylethanolamine (NAPE) molecules was detected in the HI-affected brains, and both the cytotoxic and vasogenic types of oedema were detected. In the severely affected brain areas, abnormal distributions of the monosialogangliosides GM2 and GM3 were observed in two-thirds of the animals exposed to the insult. During the late stage, a partial restoration of the brain tissue was observed in most rats in both the in vivo and ex vivo studies. These specific molecular changes may be further utilized in neonatology practice in proposing and testing novel therapeutic strategies for the treatment of neonatal HI encephalopathy.
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Affiliation(s)
- Dominika Luptakova
- Institute of Microbiology of the Czech Academy of Sciences, Prague, 142 20, Czech Republic.,Institute of Experimental Pharmacology and Toxicology, CEM of the SAS, Bratislava, 841 04, Slovakia
| | - Ladislav Baciak
- Institute of Experimental Pharmacology and Toxicology, CEM of the SAS, Bratislava, 841 04, Slovakia.,Slovak University of Technology, Central Laboratories, Bratislava, 812 37, Slovakia
| | - Tomas Pluhacek
- Institute of Microbiology of the Czech Academy of Sciences, Prague, 142 20, Czech Republic.,Regional Centre of Advanced Technologies and Materials, Department of Analytical Chemistry, Olomouc, 771 47, Czech Republic
| | - Anton Skriba
- Institute of Microbiology of the Czech Academy of Sciences, Prague, 142 20, Czech Republic
| | - Blanka Sediva
- Institute of Microbiology of the Czech Academy of Sciences, Prague, 142 20, Czech Republic
| | - Vladimir Havlicek
- Institute of Microbiology of the Czech Academy of Sciences, Prague, 142 20, Czech Republic. .,Regional Centre of Advanced Technologies and Materials, Department of Analytical Chemistry, Olomouc, 771 47, Czech Republic.
| | - Ivo Juranek
- Institute of Experimental Pharmacology and Toxicology, CEM of the SAS, Bratislava, 841 04, Slovakia
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16
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Skriba A, Havlicek V. Mass spectrometry imaging of illicit drugs in latent fingerprints by matrix-free and matrix-assisted desorption/ionization techniques. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2018; 24:124-128. [PMID: 29232991 DOI: 10.1177/1469066717728007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Compared with classical matrix-assisted laser-desorption ionization mass spectrometry (MALDI), the matrix free-based strategies generate a cleaner background, without significant noise or interference coming from an applied matrix, which is beneficial for the analysis of small molecules, such as drugs of abuse. In this work, we probed the detection efficiency of methamphetamine, heroin and cocaine in nanostructure-assisted laser desorption-ionization (NALDI) and desorption electrospray ionization and compared the sensitivity of these two matrix-free tools with a standard MALDI mass spectrometry experiment. In a typical mass spectrometry imaging (MSI) setup, papillary line latent fingerprints were recorded as a mixture a common skin fatty acid or interfering cosmetics with a drug. In a separate experiment, all drugs (1 µL of 1 μM standard solution) were detected by all three ionization techniques on a target. In the case of cocaine and heroin, NALDI mass spectrometry was the most sensitive and revealed signals even from 0.1 μM solution. The drug/drug contaminant (fatty acid or cosmetics) MSI approach could be used by law enforcement personnel to confirm drug abusers of having come into contact with the suspected drug by use of fingerprint scans at time of apprehension which can aid in reducing the work of lab officials.
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Affiliation(s)
- Anton Skriba
- Laboratory of Molecular Structure Characterization, Institute of Microbiology of the CAS, Prague, Czech Republic
| | - Vladimir Havlicek
- Laboratory of Molecular Structure Characterization, Institute of Microbiology of the CAS, Prague, Czech Republic
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17
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Luptáková D, Pluháček T, Petřík M, Novák J, Palyzová A, Sokolová L, Škríba A, Šedivá B, Lemr K, Havlíček V. Non-invasive and invasive diagnoses of aspergillosis in a rat model by mass spectrometry. Sci Rep 2017; 7:16523. [PMID: 29184111 PMCID: PMC5705710 DOI: 10.1038/s41598-017-16648-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 11/15/2017] [Indexed: 12/17/2022] Open
Abstract
Invasive pulmonary aspergillosis results in 450,000 deaths per year and complicates cancer chemotherapy, transplantations and the treatment of other immunosuppressed patients. Using a rat model of experimental aspergillosis, the fungal siderophores ferricrocin and triacetylfusarinine C were identified as markers of aspergillosis and quantified in urine, serum and lung tissues. Biomarkers were analyzed by matrix-assisted laser desorption ionization (MALDI) and electrospray ionization mass spectrometry using a 12T SolariX Fourier transform ion cyclotron resonance (FTICR) mass spectrometer. The limits of detection of the ferri-forms of triacetylfusarinine C and ferricrocin in the rat serum were 0.28 and 0.36 ng/mL, respectively. In the rat urine the respective limits of detection achieved 0.02 and 0.03 ng/mL. In the sera of infected animals, triacetylfusarinine C was not detected but ferricrocin concentration fluctuated in the 3–32 ng/mL range. Notably, the mean concentrations of triacetylfusarinine C and ferricrocin in the rat urine were 0.37 and 0.63 μg/mL, respectively. The MALDI FTICR mass spectrometry imaging illustrated the actual microbial ferricrocin distribution in the lung tissues and resolved the false-positive results obtained by the light microscopy and histological staining. Ferricrocin and triacetylfusarinine C detection in urine represents an innovative non-invasive indication of Aspergillus infection in a host.
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Affiliation(s)
- Dominika Luptáková
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Tomáš Pluháček
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,Regional Centre of Advanced Technologies and Materials, Department of Analytical Chemistry, Olomouc, 771 47, Czech Republic
| | - Miloš Petřík
- Institute of Molecular and Translational Medicine, Palacky University, Olomouc, 779 00, Czech Republic
| | - Jiří Novák
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Andrea Palyzová
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Lucie Sokolová
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Anton Škríba
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic
| | - Blanka Šedivá
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,University of West Bohemia, Plzen, 306 14, Czech Republic
| | - Karel Lemr
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic.,Regional Centre of Advanced Technologies and Materials, Department of Analytical Chemistry, Olomouc, 771 47, Czech Republic
| | - Vladimír Havlíček
- Institute of Microbiology of the Czech Academy of Sciences, Prague 4, 142 20, Czech Republic. .,Regional Centre of Advanced Technologies and Materials, Department of Analytical Chemistry, Olomouc, 771 47, Czech Republic.
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