Peptide Fragmentation Products in Mass Spectrometry Probed by Infrared Spectroscopy

2014 ◽  
pp. 153-181 ◽  
Author(s):  
Amanda L. Patrick ◽  
Nicolas C. Polfer
Keyword(s):  
Mass Spectrometry ◽  
Infrared Spectroscopy ◽  
Peptide Fragmentation

scholarly journals Characterization of a novel + 70 Da modification in rhGM-CSF expressed in E. coli using chemical assays in combination with mass spectrometry

Amino Acids ◽  
2021 ◽  
Author(s):  
Magdalena Widgren Sandberg ◽  
Jakob Bunkenborg ◽  
Stine Thyssen ◽  
Martin Villadsen ◽  
Thomas Kofoed
Keyword(s):  
Mass Spectrometry ◽  
Tandem Mass Spectrometry ◽  
Peptide Mapping ◽  
Covalent Modification ◽  
Peptide Fragmentation ◽  
Tandem Mass ◽  
E Coli ◽  
Gm Csf ◽  
Fragmentation Behavior ◽  
Macrophage Colony

AbstractGranulocyte-macrophage colony-stimulating factor (GM-CSF) is a cytokine and a white blood cell growth factor that has found usage as a therapeutic protein. During analysis of different fermentation batches of GM-CSF recombinantly expressed in E. coli, a covalent modification was identified on the protein by intact mass spectrometry. The modification gave a mass shift of + 70 Da and peptide mapping analysis demonstrated that it located to the protein N-terminus and lysine side chains. The chemical composition of C4H6O was found to be the best candidate by peptide fragmentation using tandem mass spectrometry. The modification likely contains a carbonyl group, since the mass of the modification increased by 2 Da by reduction with borane pyridine complex and it reacted with 2,4-dinitrophenylhydrazine. On the basis of chemical and tandem mass spectrometry fragmentation behavior, the modification could be attributed to crotonaldehyde, a reactive compound formed during lipid peroxidation. A low recorded oxygen pressure in the reactor during protein expression could be linked to the formation of this compound. This study shows the importance of maintaining full control over all reaction parameters during recombinant protein production.

scholarly journals New Volatile Perfluorinated Amidine–Carboxylate Copper(II) Complexes as Promising Precursors in CVD and FEBID Methods

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3145
Author(s):  
Katarzyna Madajska ◽  
Iwona Barbara Szymańska
Keyword(s):  
Electron Microscopy ◽  
Mass Spectrometry ◽  
Electron Beam ◽  
Infrared Spectroscopy ◽  
Density Functional ◽  
Variable Temperature ◽  
Chemical Vapour ◽  
Thermal Decomposition Mechanism ◽  
Transmission Electron Microscopy Analysis ◽  
Reduced Pressure

In the present study, we have synthesised and characterised newly copper(II) complexes with the general formula [Cu2(NH2(NH=)CC2F5)2(µ–O2CCRF)4], where RF = CF3, C2F5, C3F7, C4F9. Infrared spectroscopy, mass spectrometry with electron ionisation (EI MS), and density-functional theory (DFT) calculations were used to confirm compounds’ composition and structure. The volatility of the compounds was studied using thermal analysis (TGA), EI MS mass spectrometry, variable temperature infrared spectroscopy (VT IR), and sublimation experiments. Research has revealed that these compounds are the source of metal carriers in the gas phase. The thermal decomposition mechanism over reduced pressure was proposed. TGA studies demonstrated that copper transfer to the gaseous phase occurs even at atmospheric pressure. Two selected complexes [Cu2(NH2(NH=)CC2F5)2(µ–O2CC2F5)4] and [Cu2(NH2(NH=)CC2F5)2(µ–O2CC3F7)4] were successful used as chemical vapour deposition precursors. Copper films were deposited with an evaporation temperature of 393 K and 453 K, respectively, and a decomposition temperature in the range of 573–633 K without the use of hydrogen. The microscopic observations made to investigate the interaction of the [Cu2(NH2(NH=)CC2F5)2(µ–O2CC2F5)4] with the electron beam showed that the ligands are completely lost under transmission electron microscopy analysis conditions (200 keV), and the final product is copper(II) fluoride. In contrast, the beam energy in scanning electron microscopy (28 keV) was insufficient to break all coordination bonds. It was shown that the Cu-O bond is more sensitive to the electron beam than the Cu-N bond.

Combining mid infrared spectroscopy and paper spray mass spectrometry in a data fusion model to predict the composition of coffee blends

2019 ◽  
Vol 281 ◽  
pp. 71-77 ◽  
Author(s):  
Camila Assis ◽  
Hebert Vinicius Pereira ◽  
Victoria Silva Amador ◽  
Rodinei Augusti ◽  
Leandro Soares de Oliveira ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Infrared Spectroscopy ◽  
Data Fusion ◽  
Fusion Model ◽  
Paper Spray ◽  
Mid Infrared ◽  
Mid Infrared Spectroscopy

scholarly journals Quality Control Methods for Turkey Meat Products

2021 ◽  
Vol 7 (12) ◽  
pp. 92-96
Author(s):  
M. Turdialieva
Keyword(s):  
Mass Spectrometry ◽  
Quality Control ◽  
Infrared Spectroscopy ◽  
Raw Materials ◽  
Meat Products ◽  
Food Products ◽  
Control Methods ◽  
Quality And Safety ◽  
Turkey Meat ◽  
Significant Stage

The article under discussion considers methods of quality control of turkey meat products. The author believes that the quality control of food raw materials and food products is a significant stage in the production of food products. It is important to organize research aimed at improving the quality and safety of turkey meat products, using accurate, rapid, and highly effective methods of infrared spectroscopy and chromato-mass spectrometry to determine its chemical composition to develop methods to determine the correctness of HS codes.

scholarly journals Synthesis of 4-[(1H-Benzimidazol-2-yl)sulfanyl]benzaldehyde and 2-({4-[(1H-Benzimidazol-2-yl)sulfanyl]phenyl}methylidene)hydrazine-1-carbothioamide

Molbank ◽  
10.3390/m1273 ◽  
2021 ◽  
Vol 2021 (3) ◽  
pp. M1273
Author(s):  
Mustafa Turki Ubeid ◽  
Hamdy Khamees Thabet ◽  
Mohamed Yousef Abu Shuheil
Keyword(s):  
Mass Spectrometry ◽  
Infrared Spectroscopy ◽  
Nmr Spectroscopy ◽  
High Yield ◽  
Reflux Temperature

Here we describe the preparation of 2-(4-((1H-benzo[d]imidazol-2-yl)thio)-benzylidene)-hydrazine-1-carbothioamide in two steps. In the first step, 1,3-dihydro-2H-1,3-benzimidazole-2-thione was reacted with 4-fluorobenzaldehyde in DMSO to get 4-[(1H-benzimidazol-2-yl)sulfanyl]benzaldehyde in high yield. The reaction of the obtained aldehyde with thiosemicarbazide in ethanol at reflux temperature yielded 2-({4-[(1H-benzimidazol-2-yl)sulfanyl]phenyl}methylidene)hydrazine-1-carbothioamide. The structure of the synthesized compounds was established by NMR spectroscopy (1H, 13C), mass spectrometry, and infrared spectroscopy.

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