scholarly journals Neurodegenerative Proteinopathies in the Proteoform Spectrum—Tools and Challenges

2021 ◽  
Vol 22 (3) ◽  
pp. 1085
Author(s):  
Aneeqa Noor ◽  
Saima Zafar ◽  
Inga Zerr
Keyword(s):  
Mass Spectrometry ◽  
Neurodegenerative Disorders ◽  
Gel Electrophoresis ◽  
Large Fraction ◽  
Imaging Mass Spectrometry ◽  
Living Tissue ◽  
Disease Prognosis ◽  
Highly Sensitive ◽  
Jakob Disease ◽  
Hydrophobic Nature

Proteinopathy refers to a group of disorders defined by depositions of amyloids within living tissue. Neurodegenerative proteinopathies, including Alzheimer’s disease, Parkinson’s disease, Creutzfeldt–Jakob disease, and others, constitute a large fraction of these disorders. Amyloids are highly insoluble, ordered, stable, beta-sheet rich proteins. The emerging theory about the pathophysiology of neurodegenerative proteinopathies suggests that the primary amyloid-forming proteins, also known as the prion-like proteins, may exist as multiple proteoforms that contribute differentially towards the disease prognosis. It is therefore necessary to resolve these disorders on the level of proteoforms rather than the proteome. The transient and hydrophobic nature of amyloid-forming proteins and the minor post-translational alterations that lead to the formation of proteoforms require the use of highly sensitive and specialized techniques. Several conventional techniques, like gel electrophoresis and conventional mass spectrometry, have been modified to accommodate the proteoform theory and prion-like proteins. Several new ones, like imaging mass spectrometry, have also emerged. This review aims to discuss the proteoform theory of neurodegenerative disorders along with the utility of these proteomic techniques for the study of highly insoluble proteins and their associated proteoforms.

Spatial Metabolomics of the Human Kidney Using MALDI Trapped Ion Mobility Imaging Mass Spectrometry

2020 ◽  
Author(s):  
Elizabeth Neumann ◽  
Lukasz Migas ◽  
Jamie L. Allen ◽  
Richard Caprioli ◽  
Raf Van de Plas ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Ion Mobility ◽  
Imaging Mass Spectrometry ◽  
Structural Complexity ◽  
Human Kidney ◽  
Resolving Power ◽  
Mobility Separation ◽  
Trapped Ion ◽  
Mobility Data ◽  
Ion Mobility Separation

<div> <div> <p>Small metabolites are essential for normal and diseased biological function but are difficult to study because of their inherent structural complexity. MALDI imaging mass spectrometry (IMS) of small metabolites is particularly challenging as MALDI matrix clusters are often isobaric with metabolite ions, requiring high resolving power instrumentation or derivatization to circumvent this issue. An alternative to this is to perform ion mobility separation before ion detection, enabling the visualization of metabolites without the interference of matrix ions. Here, we use MALDI timsTOF IMS to image small metabolites at high spatial resolution within the human kidney. Through this, we have found metabolites, such as arginic acid, acetylcarnitine, and choline that localize to the cortex, medulla, and renal pelvis, respectively. We have also demonstrated that trapped ion mobility spectrometry (TIMS) can resolve matrix peaks from metabolite signal and separate both isobaric and isomeric metabolites with different localizations within the kidney. The added ion mobility data dimension dramatically increased the peak capacity for molecular imaging experiments. Future work will involve further exploring the small metabolite profiles of human kidneys as a function of age, gender, and ethnicity.</p></div></div>

A Novel Simultaneous Estimation of Sofosbuvir and Velpatasvir in Human Plasma by Liquid Chromatography Tandem-Mass Spectrometry after Protein Precipitation Method

2019 ◽  
Vol 15 (7) ◽  
pp. 710-715
Author(s):  
S.T. Narenderan ◽  
Basuvan Babu ◽  
T. Gokul ◽  
Subramania Nainar Meyyanathan
Keyword(s):  
Mass Spectrometry ◽  
Tandem Mass Spectrometry ◽  
Human Plasma ◽  
Multiple Reaction Monitoring ◽  
Simultaneous Estimation ◽  
Pharmacokinetic Studies ◽  
Tandem Mass ◽  
Mass Spectrometric Method ◽  
Highly Sensitive ◽  
Tandem Mass Spectrometric

Objective: The aim of the present work is to achieve a novel highly sensitive chromatographic method for the simultaneous determination of hepatitis C agents, sofosbuvir and velpatasvir from human plasma using ritonavir as an internal standard. Methods: Chromatographic separation was achieved using Hypersil C18 column (50mm x 4.6mm, 3μm) with an isocratic elution mode using the mobile phase composition 10 mM ammonium formate buffer (pH 5.0): acetonitrile (20:80 v/v) pumped at a flow rate of 0.5 ml/min. The detection was carried out by tandem mass spectrometry using Multiple Reaction Monitoring (MRM) positive Electrospray Ionization (ESI) with proton adducts at m/z 530.10 > 243.10, 883.40 > 114.0 and 721.25 > 197.0. Results: The method validated as per USFDA guidelines with respect to linearity, accuracy, and precision was found to be acceptable over the concentration range of 0.2–2000 ng/ml and 5-2000 ng/ml for sofosbuvir and velpatasvir respectively and the method was found to be highly sensitive and selective. Conclusion: The developed tandem mass spectrometric method is robust and can be applied for the monitoring of plasma levels of the analyzed drug in preclinical and clinical pharmacokinetic studies.

Proteome Analysis of CD4+ T Cells Reveals Differentially Expressed Proteins in Infertile Polycystic Ovary Syndrome Patients

2020 ◽  
Vol 20 ◽  
Author(s):  
Fatemeh Nasri ◽  
Maryam Zare ◽  
Mehrnoosh Doroudchi ◽  
Behrouz Gharesi-Fard
Keyword(s):  
Mass Spectrometry ◽  
T Cells ◽  
T Lymphocytes ◽  
Gel Electrophoresis ◽  
Cd4 T Cells ◽  
Polycystic Ovary ◽  
Proteome Analysis ◽  
Two Dimensional ◽  
Ovary Syndrome ◽  
Two Dimensional Gel Electrophoresis

Background: Polycystic ovary syndrome (PCOS) is the most frequent endocrine disorder affecting 6–7% of premenopausal women. Recent studies revealed that the immune system especially CD4+ T helper cells are important in the context PCOS. Proteome analysis of CD4+ T lymphocytes can provide valuable information regarding the biology of these cells in the context of PCOS. Objective: To investigate immune dysregulation in CD4+ T lymphocytes at the protein level in the context of PCOS using two-dimensional gel electrophoresis (2DE) and mass spectrometry (MS). Methods: In the present study, we applied two-dimensional gel electrophoresis / mass spectrometry to identify proteins differentially expressed by peripheral blood CD4+ T cells in ten PCOS women compared with ten healthy women. Western blot technique was used to confirm the identified proteins. Results: Despite the overall proteome similarities, there were significant differences in the expression of seven spots between two groups (P <0.05). Three proteins, namely phosphatidylethanolamine-binding protein 1, proteasome activator complex subunit 1 and triosephosphate isomerase 1 were successfully identified by Mass technique and confirmed by western blot. All characterized proteins were over-expressed in CD4+ T cells from patients compared to CD4+ T cells from controls (P <0.05). In-silico analysis suggested that the over-expressed proteins interact with other proteins involved in cellular metabolism especially glycolysis and ferroptosis pathway. Conclusion: These findings suggest that metabolic adjustments in CD4+ T lymphocytes, which is in favor of increased glycolysis and Th2 differentiation are important in the context of PCOS.

scholarly journals Mass Spectrometry versus Conventional Techniques of Protein Detection: Zika Virus NS3 Protease Activity towards Cellular Proteins

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3732
Author(s):  
Agnieszka Dabrowska ◽  
Aleksandra Milewska ◽  
Joanna Ner-Kluza ◽  
Piotr Suder ◽  
Krzysztof Pyrc
Keyword(s):  
Mass Spectrometry ◽  
Zika Virus ◽  
Viral Infections ◽  
Protein Detection ◽  
Extensive Discussion ◽  
Protein Targets ◽  
Highly Sensitive ◽  
Infected Cells ◽  
Ns3 Protease ◽  
To Receive

Mass spectrometry (MS) used in proteomic approaches is able to detect hundreds of proteins in a single assay. Although undeniable high analytical power of MS, data acquired sometimes lead to confusing results, especially during a search of very selective, unique interactions in complex biological matrices. Here, we would like to show an example of such confusing data, providing an extensive discussion on the observed phenomenon. Our investigations focus on the interaction between the Zika virus NS3 protease, which is essential for virus replication. This enzyme is known for helping to remodel the microenvironment of the infected cells. Several reports show that this protease can process cellular substrates and thereby modify cellular pathways that are important for the virus. Herein, we explored some of the targets of NS3, clearly shown by proteomic techniques, as processed during infection. Unfortunately, we could not confirm the biological relevance of protein targets for viral infections detected by MS. Thus, although mass spectrometry is highly sensitive and useful in many instances, also being able to show directions where cell/virus interaction occurs, we believe that deep recognition of their biological role is essential to receive complete insight into the investigated process.

Sign in / Sign up

Export Citation Format

Share Document