895: Proteomic Analysis of Sera from Bladder Cancer Patients with MALDI-TOF-MS

Background: Most of the proteomic studies in Escherichia coli have focussed on pathogenic strains, while very few studies have studied the commensal strains. It is important to study the commensal strains because under the selective pressure of their habitat, commensal strains might serve as reservoirs of virulent and pathogenic strains. Objective: In this study, we have performed a comparative proteomic analysis of commensal and pathogenic strains of E. coli isolated from a major river flowing through northern India. Methods: Proteins were resolved by two dimensional gel electrophoresis and the differentially expressed proteins were identified using matrix-assisted laser desorption ionization-time of flight mass-spectrometry (MALDI-TOF MS). Results: Many proteins of the commensal strain showed an increased expression compared to the pathogenic strain, of which seventeen proteins were identified by MALDI-TOF MS. Functional classification of these proteins revealed that they belonged to different functional pathways like energy metabolism, nucleotide and nucleoside conversions, translation, biosynthesis of amino acids and motility and energytaxis/chemotaxis. Conclusion: As per the best of our knowledge, this is the first report on comparative proteomic analysis of E. coli commensal and pathogenic strains of aquatic origin. Our results suggest that the increased production of these proteins might play an important role in adaptation of E. coli to a commensal/pathogenic lifestyle. However, further experiments are required to understand the precise role of these proteins in regulating the pathogenicity/commensalism of E. coli.

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Proteomic analysis of injured spinal cord tissue proteins using 2-DE and MALDI-TOF MS

PROTEOMICS ◽

10.1002/pmic.200500621 ◽

2006 ◽

Vol 6 (9) ◽

pp. 2797-2812 ◽

Cited By ~ 46

Author(s):

Soo Kyung Kang ◽

Hyeun Hwa So ◽

Yo Seup Moon ◽

Cheul Hong Kim

Keyword(s):

Spinal Cord ◽

Proteomic Analysis ◽

Spinal Cord Tissue ◽

Injured Spinal Cord ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

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Complementary Glycomic Analyses of Sera Derived from Colorectal Cancer Patients by MALDI-TOF-MS and Microchip Electrophoresis

Analytical Chemistry ◽

10.1021/acs.analchem.6b02310 ◽

2016 ◽

Vol 88 (19) ◽

pp. 9597-9605 ◽

Cited By ~ 31

Author(s):

Christa M. Snyder ◽

William R. Alley ◽

Margit I. Campos ◽

Martin Svoboda ◽

John A. Goetz ◽

...

Keyword(s):

Colorectal Cancer ◽

Cancer Patients ◽

Microchip Electrophoresis ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Colorectal Cancer Patients ◽

Tof Ms

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Prognostic accuracy of MALDI mass spectrometric analysis of plasma in COVID-19

10.1101/2020.10.01.20205310 ◽

2020 ◽

Cited By ~ 1

Author(s):

Lucas Cardoso Lazari ◽

Fabio De Rose Ghilardi ◽

Livia Rosa-Fernandes ◽

Diego M Assis ◽

José Carlos Nicolau ◽

...

Keyword(s):

Plasma Protein ◽

Proteomic Analysis ◽

Serum Amyloid A ◽

Low Risk ◽

Serum Amyloid ◽

Bottom Up ◽

Maldi Tof Ms ◽

Amyloid A ◽

Maldi Tof ◽

Tof Ms

AbstractPurposeSARS-CoV-2 infection poses a global public health problem. There is a critical need for improvements in the noninvasive prognosis of COVID-19. We hypothesized that matrix-assisted laser desorption ionization mass spectrometry (MALDI-TOF MS) analysis combined with bottom-up proteomic analysis of plasma proteins might identify features to predict high and low risk cases of COVID-19.Patients and MethodsWe used MALDI-TOF MS to analyze plasma small proteins and peptides isolated using C18 micro-columns from a cohort containing a total of 117 cases of high (hospitalized) and low risk (outpatients) cases split into training (n = 88) and validation sets (n= 29). The plasma protein/peptide fingerprint obtained was used to train the algorithm before validation using a blinded test cohort.ResultsSeveral sample preparation, MS and data analysis parameters were optimized to achieve an overall accuracy of 85%, sensitivity of 90%, and specificity of 81% in the training set. In the blinded test set, this signature reached an overall accuracy of 93.1%, sensitivity of 87.5%, and specificity of 100%. From this signature, we identified two distinct regions in the MALDI-TOF profile belonging to the same proteoforms. A combination of 1D SDS-PAGE and quantitative bottom-up proteomic analysis allowed the identification of intact and truncated forms of serum amyloid A-1 and A-2 proteins. Conclusions: We found a plasma proteomic profile that discriminates against patients with high and low risk COVID-19. Proteomic analysis of C18-fractionated plasma may have a role in the noninvasive prognosis of COVID-19. Further validation will consolidate its clinical utility.Key messageWhat is the key question?Do individuals infected with SARS-CoV-2 harboring different degree of disease severity have a plasma protein profile that differentiate them and predict the COVID-19 outcome?What is the bottom line?In a series of 117 patients with COVID-19 divided in hospitalized (60) and outpatients (57), differential expression of serum amyloid A-1 (SAA1) and A-2 (SAA2) predict their outcome.Why read on?The high mortality rate in SARS-CoV-2 infected individuals requires accurate markers for predicting COVID-19 severity. Plasma levels of SAA1 and SAA2 indicate higher risk of hospitalization and can be used to improve COVID-19 monitoring and therapy.

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Proteomic analysis of proteins differentially expressed in conidia and mycelium of the entomopathogenic fungus Aschersonia placenta

Canadian Journal of Microbiology ◽

10.1139/w2012-111 ◽

2012 ◽

Vol 58 (12) ◽

pp. 1327-1334 ◽

Cited By ~ 4

Author(s):

Junzhi Qiu ◽

Yubin Su ◽

Ivan Gelbǐc ◽

Yunfeng Qiu ◽

Xiaocong Xie ◽

...

Keyword(s):

Proteomic Analysis ◽

Entomopathogenic Fungus ◽

Developmental Stages ◽

Differentially Expressed ◽

Uridine Diphosphate ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Oxidation Reduction ◽

Tof Ms

The infection of insects by the entomopathogenic fungus Aschersonia placenta depends on conidia. To identify proteins differentially expressed in A. placenta conidia vs mycelia, we performed a comparative proteomic analysis of A. placenta using 2-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI-TOF-MS). We detected 1022 2-DE protein spots in conidia and 1049 in mycelia and analyzed 48 (13 from conidia and 35 from mycelia) using MALDI-TOF-MS. Finally, we identified 28 proteins (7 from conidia and 21 from mycelia). The identified proteins exclusive to conidia included major proteins participating in oxidation–reduction processes and vegetative insecticidal protein 1 (Vip1), a protein that is likely involved in pathogenicity. The identified proteins exclusive to mycelia were those involved in biosynthesis and metabolism, including uridine diphosphate galactopyranose mutase, which might play key roles in hyphal morphogenesis. This report provides the first proteomic analysis of different developmental stages of an Aschersonia species. Although only a small number of proteins were identified, the data represent a useful foundation for future studies concerning the molecular basis of entomopathogenicity in the species A. placenta and in the genus Aschersonia.

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Identification of Differential N-Glycan Compositions in the Serum and Tissue of Colon Cancer Patients by Mass Spectrometry

Biology ◽

10.3390/biology10040343 ◽

2021 ◽

Vol 10 (4) ◽

pp. 343

Author(s):

Marcelo de M.A. Coura ◽

Eder A. Barbosa ◽

Guilherme D. Brand ◽

Carlos Bloch ◽

Joao B. de Sousa

Keyword(s):

Mass Spectrometry ◽

Colon Cancer ◽

Cancer Patients ◽

Total Serum ◽

Healthy Controls ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Cancer Tumor ◽

Glycan Profiling ◽

Tof Ms

Colorectal cancer (CRC) ranks second as the leading cause of cancer-related deaths worldwide. N-glycosylation is one of the most common posttranslational protein modifications. Therefore, we studied the total serum N-glycome (TSNG) of 13 colon cancer patients compared to healthy controls using MALDI-TOF/MS and LC-MS. N-glycosylation of cancer tumor samples from the same cohort were further quantified using a similar methodology. In total, 23 N-glycan compositions were down-regulated in the serum of colon cancer patients, mostly galactosylated forms whilst the mannose-rich HexNAc2Hex7, the fucosylated bi-antennary glycan HexNAc4Hex5Fuc1NeuAc2, and the tetra-antennary HexNAc6Hex7NeuAc3 were up-regulated in serum. Hierarchical clustering analysis of TSNG correctly singled out 85% of the patients from controls. Albeit heterogenous, N-glycosylation of tumor samples showed overrepresented oligomannosidic, bi-antennary hypogalactosylated, and branched compositions related to normal colonic tissue, in both MALDI-TOF/MS and LC-MS analysis. Moreover, compositions found upregulated in tumor tissue were mostly uncorrelated to compositions in serum of cancer patients. Mass spectrometry-based N-glycan profiling in serum shows potential in the discrimination of patients from healthy controls. However, the compositions profile in serum showed no parallel with N-glycans in tumor microenvironment, which suggests a different origin of compositions found in serum of cancer patients.

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