Robust Glycan and Glycopeptide Database
SimGlycan®database is a large relational database containing 9,165 glycans, 22,814 glycoproteins*, 6,027 glycans with known biological sources and 5,874 glycans with known classes. The database is continuously updated as information on additional glycans is published.
*The glycoproteins have been curated from The UniProt Consortium.
UniProt: a hub for protein information
Nucleic Acids Res. 43: D204-D212 (2015)
Support for MALDI MS/MS and LC-MS/MS Workflows
With comprehensive support for different adducts such as H, Li, Na, Mg2+, K, HCOO- and NH4+ and adduct
combinations such as Na + H, Li + H etc. along with scalable MS/MS fragmentation patterns based on different
instrument settings, SimGlycan® can analyze MALDI – and LC- MS/MS data for glycopeptides and released
glycans that are underivatized, permethylated and reducing end modified with no compromise on the results of
Data Input File Formats
SimGlycan® allows direct automatic loading of input data files generated by mass spectrometers from SCIEX
(TripleTOF™ 5600 System, TOF/TOF 5800, 4800 Plus MALDI TOF/TOF™ Analyzer, 4000 QTRAP® and
QSTAR® Elite Systems), Agilent Technologies (Agilent 6200 Series TOF LC/MS and Agilent 6500 Series Q-TOF
LC/MS systems), Bruker Corporation (ultrafleXtreme™ MALDI TOF/TOF, ultraflex™ MALDI TOF/TOF, autoflex™
TOF and TOF/TOF, maXis™ UHR-TOF, micrOTOF™, micrOTOF-Q™, solariX™ Qq-FTMS, and amaZon™ ion
trap series), Thermo Scientific™ (LTQ FT Ultra, LTQ Velos, LTQ XL, LTQ Orbitrap Discovery, LTQ Orbitrap
Velos, LTQ Orbitrap XL, MALDI LTQ Orbitrap, Orbitrap Elite, Q Exactive and Thermo Scientific™ Orbitrap™
Fusion™ Tribrid mass spectrometer and Thermo Scientific™ Q Exactive™ hybrid quadrupole-Orbitrap mass
spectrometer) and Waters Corporation (SYNAPT G2 HDMS, SYNAPT G2 MS, Xevo G2 QTof, Xevo QTof MS,
Xevo TQ MS and Xevo TQ-S platforms). Other mass spectrometers are supported using mzData and mzXML
formats. Besides, manual entry, TXT and XLS file formats are also accepted by SimGlycan®. No matter what
make your instrument is, the output can be converted to these formats using third party tools.
Accurate Ranking Mechanism
All possible glycan/glycopeptide structures are ranked and scored based on our proprietary search and score
mechanism. The ranking mechanism is based on calculating the proximity score, which is a numerical
representation of how closely the experimental properties (composition and branching pattern) of the
glycan/glycopeptide match with those of the glycans/glycopeptides in the database.
Additional Filters For Precise Results
SimGlycan® enables users to specify filters based on class, sub class and biological source. Additionally, users can specify the number of antennae, reducing terminal monosaccharide and non-reducing terminal monosaccharides expected in the structure, thereby enhancing the accuracy of the final search result.
Comprehensive Result Analysis
For every probable glycan or glycopeptide structure, SimGlycan® provides in-silico fragments, structure, sequence, composition, chemical formula, molecular mass, class etc..
LC-MS and LC- MS/MS Data Processing
SimGlycan® processes LC-MS and LC-MS/MS data for peak detection, separation of isomeric compounds that
are eluted under a single peak, isotope cluster identification, selection of accurate precursor m/z for MS/MS
scans, identification of MS/MS scans corresponding to different isomers and peak alignment. The parameters for
peak detection can be customized to either detect glycans or glycopeptides. SimGlycan® can read LC-MS and
MS/MS raw data from leading mass spectrometer vendors. SimGlycan® reads LC-MS and MS/MS peaklist data
directly from Agilent's .cef files and assigns the ion species of MS/MS precursor m/z by probing its parent MS
High Throughput Analysis
Rapid advancement in mass spectrometry enables high throughput experimentation for glycan identification. To keep pace with such advancements, SimGlycan® can analyze LC-tandem MS runs containing hundreds of scans in batch mode. Furthermore, users can create and use search parameter templates that can be applied to all data sets. Users can perform glycan/glycopeptide search for high resolution accurate mass (HRAM) data with an
error tolerance up to 20 parts per million (ppm) or 2000 milli Dalton (mDa).
SimGlycan® now supports the Mass Spectrometry-based quantitative glycomics workflow using aminoxyTandem
Mass Tags (TMT). aminoxyTMT6 reagents enable efficient relative quantitation of glycans, improving labeled-glycan
ionization efficiency thereby increasing analytical throughput. Glycans are quantified by measuring reporter ion peak intensities from the corresponding MS/MS spectra. User can specify a tolerance as small as 0.0001.
Following extraction of peak intensities, the aminoxyTMT reporter ion signals are adjusted to account for isotopic
impurities in each TMT variant. Users can select the sum/average/median reporter ion intensities across all
glycan-spectral matches as the quantity of a glycan. Various charts such as bar chart, dot-plot etc. are plotted to facilitate visualization of the quantity of each glycan in different TMT channels and across biological samples.
Multi Stage Mass Spectrometry (MSn) Data Analysis
SimGlycan® includes comprehensive support to perform Multi Stage/Sequential Mass Spectrometry (MSn) data analysis. MSn, a technique wherein the product ions from MS/MS (or previous stage MS) are subjected to refragmentation,
is one of the most effective techniques in resolving heterogeneity, branching pattern and isobaric
oligosaccharide structures. It allows discrimination of glycans having similar characteristic fragment patterns
which are otherwise indistinguishable in MS/MS spectra. As the level of MS (n) increases, generated fragments
become structure specific which assists in resolving isobaric oligosaccharides or detailed characterization of
Glycopeptide Qualitative Analysis
Many of the mass spectrometers allows the capture of MS/MS data as compounds elute from in line separation systems. Such LC-MS/MS approaches generate extremely large datasets, requiring sophisticated informatics tool to assign glycopeptide structures over a complete chromatographic separation. This would enhance analytic
productivity and provide greater depth of analysis of mass spectrometric glycoproteomic data. SimGlycan® now
includes comprehensive support for identifying glycopeptides of complex mixtures separated by LC and detected
by MS/MS in batch processing mode. The Protein ID, Protein sequence or Peptide sequences identified by using
a third party tool will be used by SimGlycan® as initial input. SimGlycan® identifies probable glycan-peptide combinations and ranks them on the basis of observed peaks in the MS/MS data corresponding to diagnostic
ions from theoretical glycopeptide. High resolution accurate mass data with an error tolerance between 1 to 20
parts per million (ppm) and 0.1 to 2000 milli Dalton (mDa) can be analyzed.
SimGlycan® provides a comprehensive project management, associating results with input profile and search
parameters. You can open any number of projects. Users can import 20,000 spectra in a project. The projects can be classified on the basis of the source, the lab or the research goal. This is important, especially when
conducting large-scale glycan analysis projects.
You can access glycan related information at the click of a button. Unlike web based applications, SimGlycan®
saves it on your own computer. The available information consists of:
Glycan Structure: Displays the molecular structure (carbohydrate sequence) of the glycan.
Glycan Fragments: Displays the nomenclature, structure, m/z value and mass using Domon Costello rules of
fragmentation. A serial number is assigned to each fragment.
i) Glycosidic Fragments: Single glycosidic and glycosidic/glycosidic fragments are displayed.
ii) Cross Ring Fragments: Single cross ring and glycosidic/cross ring fragments are displayed.
Glycopeptide Structure: Displays the peptide sequence and the sites of protein glycosylation along with the
Annotate Mass Spectra and Generate Reports
SimGlycan® can annotate mass spectra using cartoons or Domon-Costello nomenclature. The charge state of
the fragment is also depicted. Read more...
Export Annotated Peaklist table
Users can export annotated peaklist for all search results from 20,000 MS/MS spectra to single project report. Users can include either only the matched fragments or both matched and unmatched fragments in the annotated peaklist table.
SimGlycan® enables users to draw and edit glycan and glycopeptide structures. A monosaccharide, peptide
chain or a substituent such as HSO3, Etn can be added or deleted and branching points and anomeric linkages can be modified at the click of a button. At each step, the fragmentation of the drawn structure enables a user to
compare the experimental and theoretical data, enabling the user to see whether his modification brings the theoretical glycan closer to the experimental data. This feature greatly assists in resolving glycan structures, especially when data for glycans of interest is not yet available.
Mass Spectra Interpretation
SimGlycan® helps in interpreting a mass spectra by highlighting the experimental m/z values that match those of
theoretical fragments and generates an annotated spectrum depicting the loss of consecutive monosaccharide
units. This helps researcher to establish the branching pattern and verifying the basic unit of glycan. Each peak
can be represented using cartoons or Domon Costello nomenclature. Charge states of fragments are also
displayed if the fragments are multiply charged.
SimGlycan® enables generating an annotated mass spectra either to fit on a page or based on the area of
interest. It also exports it for sharing the findings with your colleagues. The simple interface enables you to zoom
into specific plot locations, specify m/z range to display specific plot sections and also to export plots as image
files to MS PowerPoint, for publishing results and sharing information with colleagues.
Cartoons are constructed using standard Consortium for Functional Glycomics (CFG) nomenclature for
monosaccharides (custom symbols are used where CFG annotations are not available). You can simultaneously plot all types of glycosidic fragments while annotating the spectra in symbolic representation format.
* This feature is available in the SimGlycan® Enterprise Edition.