title: Polylactosaminoglycan glycomics: enhancing the detection of high-molecular-weight N-glycans in matrix-assisted laser desorption ionization time-of-flight profiles by matched filtering.
abstract: For over 30 years, protocols based on the mass spectrometry (MS) of permethylated derivatives, complemented by enzymatic degradations, have underpinned glycomic experiments aimed at defining the structures of individual glycans present in the complex mixtures that are characteristic of biological samples. Both MS instrumentation and sample handling have improved markedly in recent years, enabling greater sensitivity and better signal-to-noise ratios, thereby facilitating the detection of glycans at much higher masses than could be achieved in the past. The latter is especially important for the characterization of the biologically important class of N-glycans that carry polylactosaminoglycan chains. Such advances in data acquisition heighten the need for informatics tools to assist in glycan structure assignment. Here, utilizing mouse lung tissue as a model system, we present evidence of polylactosaminoglycan-containing N-glycans with permethylated molecular weights exceeding 13 kDa. We show that antennae branching patterns and lengths can be successfully determined at these high masses via MS/MS experiments, even when MS ion counts are very low. We also describe the development and application of a matched filtering algorithm for assisting high-molecular-weight glycan detection and structure assignment.
authors: Palo Alto Research Center, 3333 Coyote Hill Road, Palo Alto, California 94304, USA. rn@parc.com
authors: Marshall
authors: M
authors: Bern
authors: Alejandro E
authors: AE
authors: Brito
authors: Poh-Choo
authors: PC
authors: Pang
authors: Angad
authors: A
authors: Rekhi
authors: Anne
authors: A
authors: Dell
authors: Stuart M
authors: SM
authors: Haslam
mesh_terms: D000465:Algorithms; D000606:Amino Sugars / Q000737:chemistry* / Q000378:metabolism; D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D054794:Glycomics; D008168:Lung / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D058977:Molecular Sequence Annotation / Q000379:methods; D008969:Molecular Sequence Data; D008970:Molecular Weight; D011134:Polysaccharides / Q000737:chemistry* / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000606:Amino Sugars; D011134:Polysaccharides; C039448:lactosaminoglycan