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Search Publications by: Stephen E. Stein (Fed)

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Displaying 1 - 25 of 191

Molecular Oxygen (O2) Artifacts in Tandem Mass Spectra

November 20, 2024
Author(s)
Yuxue Liang, Pedatsur Neta, Xiaoyu (Sara) Yang, Hugo Garraffo, Tallat Bukhari, Yi Liu, Stephen Stein
The NIST 2023 tandem mass spectral library contains 1,832,086 spectra of positive ions and 541,978 of negative ions from 51,501 compounds. Peak annotation plays an important role in spectrum evaluation. While most fragment ions are formed by neutral losses

Variation of Site-Specific Glycosylation Profiles of Recombinant Influenza Glycoproteins

August 9, 2024
Author(s)
Zachary Goecker, Meghan Burke Harris, Concepcion Remoroza, Yi Liu, Yuri Mirokhin, Sergey Sheetlin, Dmitrii V. Tchekhovskoi, Xiaoyu (Sara) Yang, Stephen E. Stein
This work presents a detailed determination of site-specific N-glycan distributions of the recombinant influenza glycoproteins hemagglutinin (HA) and neuraminidase. Variation in glycosylation among recombinant glycoproteins is not predictable and can

Comparison of N-glycopeptide to released N-glycan abundances and the influence of glycopeptide mass and charge state on N-linked glycosylation of IgG antibodies

March 7, 2024
Author(s)
Concepcion Remoroza, Meghan Burke Harris, Tytus Mak, Sergey Sheetlin, Yuri Mirokhin, Zachary Goecker, Brian T. Cooper, Mark Lowenthal, Xiaoyu (Sara) Yang, Guanghui Wang, Dmitrii V. Tchekhovskoi, Stephen E. Stein
We report the comparison of mass-spectral-based abundances of tryptic glycopeptides to fluorescence abundances of released labeled glycans and the effects of mass and charge state and in-source fragmentation on glycopeptide abundances. The primary

An Improved Sample Preparation Method for Protein and Peptide Identification from Human Hair

November 27, 2023
Author(s)
Zheng Zhang, William E. Wallace, Guanghui Wang, Meghan Burke Harris, Yi Liu, Sergey Sheetlin, Stephen E. Stein
A fast and sensitive Direct Extraction (DE) method developed in our group can efficiently extract proteins in 30 min from a 5 cm-long hair strand. Previously we coupled DE to downstream analysis using gel electrophoresis followed by in-gel digestion, which

Determining Site-Specific Glycan Profiles of Recombinant SARS-CoV-2 Spike Proteins from Multiple Sources

August 30, 2023
Author(s)
Meghan Burke Harris, Yi Liu, Concepcion Remoroza, Yuri Mirokhin, Sergey Sheetlin, Dmitrii V. Tchekhovskoi, Guanghui Wang, Xiaoyu (Sara) Yang, Stephen E. Stein
Glycopeptide Abundance Distribution Spectra (GADS) were recently introduced as a means of representing, storing and comparing glycan profiles of intact glycopeptides. Here, using that representation, an extensive analysis is made of multiple commercial

Inferring the nominal molecular mass of an analyte from its electron ionization mass spectrum

August 23, 2023
Author(s)
Arun Moorthy, Anthony J. Kearsley, William Mallard, William E. Wallace, Stephen E. Stein
The performance of three algorithms for predicting nominal molecular mass from an analyte's electron ionization mass spectrum is presented. The Peak Interpretation Method (PIM) attempts to quantify the likelihood that a molecular ion peak is contained in

Mass Spectral Library Methods for Analysis of Site-Specific N-Glycosylation: Application to Human Milk Proteins

September 16, 2022
Author(s)
Concepcion Remoroza, Meghan Burke Harris, Xiaoyu (Sara) Yang, Sergey Sheetlin, Yuri Mirokhin, Sanford Markey, Dmitrii V. Tchekhovskoi, Stephen E. Stein
We present a mass-spectral library-based method for analyzing site-specific N-linked protein glycosylation. Its operation and utility are illustrated by applying it to both newly measured and available proteomics data of human milk glycoproteins. It

Representing and Comparing Site-Specific Glycan Abundance Distributions of Glycoproteins

July 30, 2021
Author(s)
Concepcion Remoroza, Meghan Burke Harris, Yi Liu, Yuri Mirokhin, Dmitrii V. Tchekhovskoi, Xiaoyu (Sara) Yang, Stephen E. Stein
A method for representing and comparing distributions of N-linked glycans located at specific sites in proteins is presented. The representation takes the form of a simple mass spectrum for a given peptide sequence, with each peak corresponding to a

MS_Piano: A Software Tool for Annotating Peaks in CID Tandem Mass Spectra of Peptides and N-Glycopeptides

July 15, 2021
Author(s)
Xiaoyu (Sara) Yang, Pedatsur Neta, Yuri Mirokhin, Dmitrii V. Tchekhovskoi, Concepcion Remoroza, Meghan Burke Harris, Yuxue Liang, Sanford Markey, Stephen E. Stein
Annotating product ion peaks in tandem mass spectra is essential for evaluating spectral quality and validating peptide identification. This task is more complex for glycopeptides and is crucial for the confident determination of glycosylation sites in

Comprehensive Analysis of Tryptic Peptides Arising from Disulfide Linkages in NISTmAb and Their Use for Developing a Mass Spectral Library

June 22, 2021
Author(s)
Qian Dong, Xinjian Yan, Yuxue Liang, Sanford Markey, Sergey L. Sheetlin, Concepcion Remoroza, William E. Wallace, Stephen Stein
This work presents methods for identifying and then creating a mass spectral library for disulfide-linked peptides originating from the NISTmAb. Analysis involved both partially- reduced and non-reduced proteins under neutral and weakly basic conditions