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Search Publications by: Stephen E. Stein (Fed)

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Displaying 1 - 25 of 90

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

Increasing the Coverage of a Mass Spectral Library of Milk Oligosaccharides Using a Hybrid- Search-Based Bootstrapping Method and Milks from a Wide Variety of Mammals

July 8, 2020
Author(s)
Concepcion A. Remoroza, Tytus D. Mak, Yuri A. Mirokhin, Sergey L. Sheetlin, Xiaoyu Yang, Stephen E. Stein, Power L. Michael, San Andres V. Joice, Yuxue Liang
This study significantly expands both the scope and method of identification for construction of a previously reported tandem mass spectral library of 74 human milk oligosaccharides (HMOs) derived from results of LC-MS/MS experiments. In the present work

Mass Spectral Library of Acylcarnitines Derived from Human Urine

April 8, 2020
Author(s)
Xinjian Yan, Sanford Markey, Ramesh Marupaka, Qian Dong, Brian T. Cooper, Yuri Mirokhin, William E. Wallace, Stephen Stein
We describe the creation of a mass spectral library of acylcarnitines and conjugated acylcarnitines from the LC–MS/MS analysis of six NIST urine reference materials. To recognize acylcarnitines, we conducted in-depth analyses of fragmentation patterns of

Sensitive Method for the Confident Identification of Genetically Variant Peptides in Human Hair

October 31, 2019
Author(s)
Zheng Zhang, Meghan Burke, William E. Wallace, Yuxue Liang, Sergey L. Sheetlin, Yuri Mirokhin, Dmitrii Tchekhovskoi, Stephen Stein
Recent reports have demonstrated that genetically variant peptides (GVPs) derived from human hair shaft proteins can be used to differentiate individuals of different biogeographic origin (Parker, G.J.; et al. PLos One. 2016, e0160653). We report a direct

Mass Spectrometry Fingerprints of Small-Molecule Metabolites in Biofluids. Building a Spectral Library of Recurrent Spectra for Urine Analysis.

August 19, 2019
Author(s)
Yamil Simon, Ramesh Marupaka, Xinjian Yan, Yuxue Liang, Kelly H. Telu, Yuri A. Mirokhin, Stephen E. Stein
A large fraction of ions observed in electrospray liquid chromatography-mass spectrometry (LC-MS) experiments of biological samples remain unidentified. One the main reasons for this is that spectral libraries of pure compounds fail to account for the

Mass Spectrometry Fingerprints of Small-Molecule Metabolites in Biofluids: Building a Spectral Library of Recurrent Spectra for Urine Analysis

August 18, 2019
Author(s)
Yamil Simon, Ramesh Marupaka, Xinjian Yan, Yuxue Liang, Kelly H. Telu, Yuri Mirokhin, Stephen E. Stein
A large fraction of ions observed in electrospray liquid chromatography–mass spectrometry (LC–ESI-MS) experiments of biological samples remain unidentified. One of the main reasons for this is that spectral libraries of pure compounds fail to account for

Cross-Ring Fragmentation Patterns in the Tandem Mass Spectra of Underivatized Sialylated Oligosaccharides and Their Special Suitability for Spectrum Library Searching

December 18, 2018
Author(s)
M. L. De Leoz, Yamil Simon, Robert J. Woods, Stephen E. Stein
Reference spectral library searching, while widely used to identify compounds in other areas of mass spectrometry, is not commonly used in glycomics. Building on a study by Cotter and coworkers on analysis of sialylated oligosaccharides using atmospheric

Creating a Mass Spectral Reference Library for Oligosaccharides in Milk

July 3, 2018
Author(s)
Concepcion A. Remoroza, Tytus D. Mak, M. L. De Leoz, Yuri A. Mirokhin, Stephen E. Stein
We report the development and availability of a mass spectral reference library for oligosaccharides in human milk. This represents a new variety of spectral library that includes consensus spectra of compounds annotated through various data analysis

The NISTmAb Tryptic Peptide Spectral Library for Monoclonal Antibody Characterization

March 6, 2018
Author(s)
Qian Dong, Yuxue Liang, Xinjian Yan, Sanford Markey, Yuri Mirokhin, Dmitrii V. Tchekhovskoi, Tallat H. Bukhari, Stephen E. Stein
We describe the creation of a mass spectral library composed of all identifiable spectra derived from the tryptic digest of a therapeutic monoclonal antibody. The NISTmAb library is a unique reference peptide spectral library developed from a total of six

Reverse and Random Decoy Methods for False Discovery Rate Estimation in High Mass Accuracy Peptide Spectral Library Searches

February 2, 2018
Author(s)
Zheng Zhang, Meghan C. Burke, Yuri A. Mirokhin, Dmitrii V. Tchekhovskoi, Sanford P. Markey, Wen Yu, Raghothama Chaerkady, Sonja Hess, Stephen E. Stein
Spectral library searching (SLS) is an attractive alternative to sequence database searching (SDS) for peptide identification due to its speed, sensitivity, and ability to include any selected mass spectra. However, SLS does not have a widely tested and

Combining fragment ion and neutral loss matching during mass spectral library searching: A new general-purpose algorithm applicable to illicit drug identification

November 20, 2017
Author(s)
Arun S. Moorthy, William E. Wallace, Anthony J. Kearsley, Dmitrii V. Tchekhovskoi, Stephen E. Stein
A mass spectral library search algorithm that identifies compounds that differ from library compounds by a single ‘inert’ structural component is described. This algorithm, the Hybrid Similarity Search, generates a similarity score based on matching both

Collision-Induced Dissociation of Deprotonated Peptides. Relative Abundance of Side-Chain Neutral Losses, Residue-Specific Product Ions, and Comparison with Protonated Peptides

November 14, 2017
Author(s)
Yuxue Liang, Pedatsur Neta, Xiaoyu (Sara) Yang, Stephen E. Stein
High-accuracy MS/MS spectra of deprotonated ions of 390 dipeptides and 137 peptides with 3 to 6 residues are studied. Many amino acid residues undergo neutral losses from their side chains. The most abundant is the loss of acetaldehyde from threonine. The