University of Wisconsin- Madison

3 ARTICLES PUBLISHED IN JoVE

Biology

MALDI-Mass Spectrometric Imaging for the Investigation of Metabolites in Medicago truncatula Root Nodules

¹Department of Chemistry, University of Wisconsin- Madison, ²School of Pharmacy, University of Wisconsin- Madison

Mass spectrometric imaging (MSI) is a powerful tool that can be used to discover and identify various chemical species in intact tissues, preserving the compounds in their native environments, which can provide new insights into biological processes. Herein a MSI method developed for the analysis of small molecules is described.

Chemistry

Multi-Faceted Mass Spectrometric Investigation of Neuropeptides in Callinectes sapidus

Ashley Phetsanthad^*1, Nhu Q. Vu^*1, Lingjun Li^1,2

¹Department of Chemistry, University of Wisconsin-Madison, ²School of Pharmacy, University of Wisconsin-Madison

Mass spectrometric characterization of neuropeptides provides sequence, quantitation, and localization information. This optimized workflow is not only useful for neuropeptide studies, but also other endogenous peptides. The protocols provided here describe sample preparation, MS acquisition, MS analysis, and database generation of neuropeptides using LC-ESI-MS, MALDI-MS spotting, and MALDI-MS imaging.

Biochemistry

A Spin-Tip Enrichment Strategy for Simultaneous Analysis of N-Glycopeptides and Phosphopeptides from Human Pancreatic Tissues

Dylan Nicholas Tabang¹, Danqing Wang¹, Lingjun Li^1,2

¹Department of Chemistry, University of Wisconsin-Madison, ²School of Pharmacy, University of Wisconsin-Madison

Post-translational modifications (PTMs) change protein structures and functions. Methods for the simultaneous enrichment of multiple PTM types can maximize coverage in analyses. We present a protocol using dual-functional Ti(IV)-immobilized metal affinity chromatography followed by mass spectrometry for the simultaneous enrichment and analysis of protein N-glycosylation and phosphorylation in pancreatic tissues.