scholarly journals Detecting the Site of Phosphorylation in Phosphopeptides without Loss of Phosphate Group Using MALDI TOF Mass Spectrometry

2008 ◽  
Vol 3 ◽  
pp. ACI.S497 ◽  
Author(s):  
Medicharla V. Jagannadham ◽  
Ramakrishnan Nagaraj
Keyword(s):  
Mass Spectrometry ◽  
Negative Ions ◽  
Maldi Mass Spectrometry ◽  
Phosphate Group ◽  
Maldi Tof Mass Spectrometry ◽  
Linear Mode ◽  
Maldi Tof ◽  
Phosphorylated Peptides ◽  
Delayed Extraction ◽  
Phosphate Groups

Phosphopeptides with one and four phosphate groups were characterized by MALDI mass spectrometry. The molecular ion of monophosphopeptide could be detected both as positive and negative ions by MALDI TOF with delayed extraction (DE) and in the reflector mode. The tetraphospho peptide could be detected in linear mode. When MS/MS spectra of the monophospho peptides were obtained in a MALDI TOF TOF instrument by CID, b and y ions with the intact phosphate group were observed, in addition the b and y ions without the phosphate group. Our study indicates that it is possible to detect phosphorylated peptides with out the loss of phosphate group by MALDI TOF as well as MALDI TOF TOF instruments with delayed extraction and in the reflector mode.

Enhanced Ionization of Phosphorylated Peptides during MALDI TOF Mass Spectrometry

2004 ◽  
Vol 76 (5) ◽  
pp. 1532-1536 ◽  
Author(s):  
Xiaofeng Yang ◽  
Huaping Wu ◽  
Tomoyoshi Kobayashi ◽  
R. John Solaro ◽  
Richard B. van Breemen
Keyword(s):  
Mass Spectrometry ◽  
Maldi Tof Mass Spectrometry ◽  
Maldi Tof ◽  
Phosphorylated Peptides

Utilization of the Linear Mode of MALDI-TOF Mass Spectrometry in the Study of Glycation During the Malting Process

2010 ◽  
Vol 116 (3) ◽  
pp. 245-250 ◽  
Author(s):  
Markéta Laštovičková ◽  
Karel Mazanec ◽  
Dagmar Benkovská ◽  
Janette Bobál'ová
Keyword(s):  
Mass Spectrometry ◽  
Maldi Tof Mass Spectrometry ◽  
Linear Mode ◽  
Maldi Tof

scholarly journals Putative Protein Biomarkers of Escherichia coli Antibiotic Multiresistance Identified by MALDI Mass Spectrometry

Biology ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 56 ◽  
Author(s):  
Telma de Sousa ◽  
Didier Viala ◽  
Laetitia Théron ◽  
Christophe Chambon ◽  
Michel Hébraud ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Mass Range ◽  
Maldi Mass Spectrometry ◽  
Extended Spectrum Beta Lactamase ◽  
E Coli ◽  
Machine Learning Classification ◽  
Linear Mode ◽  
Maldi Tof

The commensal bacteria Escherichia coli causes several intestinal and extra-intestinal diseases, since it has virulence factors that interfere in important cellular processes. These bacteria also have a great capacity to spread the resistance genes, sometimes to phylogenetically distant bacteria, which poses an additional threat to public health worldwide. Here, we aimed to use the analytical potential of MALDI-TOF mass spectrometry (MS) to characterize E. coli isolates and identify proteins associated closely with antibiotic resistance. Thirty strains of extended-spectrum beta-lactamase producing E. coli were sampled from various animals. The phenotypes of antibiotic resistance were determined according to Clinical and Laboratory Standards Institute (CLSI) methods, and they showed that all bacterial isolates were multi-resistant to trimethoprim-sulfamethoxazole, tetracycline, and ampicillin. To identify peptides characteristic of resistance to particular antibiotics, each strain was grown in the presence or absence of the different antibiotics, and then proteins were extracted from the cells. The protein fingerprints of the samples were determined by MALDI-TOF MS in linear mode over a mass range of 2 to 20 kDa. The spectra obtained were compared by using the ClinProTools bioinformatics software, using three machine learning classification algorithms. A putative species biomarker was also detected at a peak m/z of 4528.00.

Sign in / Sign up

Export Citation Format

Share Document