Tags: Analytical Seminar

De novo protein design has experienced a renaissance in recent years due to advances in generative diffusion-based approaches to develop high affinity, target-specific binders. However, the ability of these tools to generate “new-to-nature” proteins with unique backbones and amino acid sequences that target lipid/protein assemblies has not yet been explored. Here, we apply an end-to-end design pipeline using RFdiffusionAA, LigandMPNN, Chai-…
Glycosaminoglycans (GAGs), linear polysaccharides found near the cell membrane as proteoglycans and free oligosaccharides, play important roles regarding cell functions. GAGs have been implicated as potential biomarkers in many diseases like cancer and kidney related diseases and are used as therapeutics for many types of ailments. Because they are highly sulfated, complex GAGs have been analyzed with reverse polarity capillary electrophoresis (…
Cellular processes depend on the coordinated function of all proteoforms—the distinct molecular forms of a protein that arise from mechanisms such as alternative splicing and post-translational modifications. Different proteoforms can have distinct free energy landscapes that may alter their structures, motions, and interactions with other proteins. As a result, changes in proteoforms can alter cellular regulation and lead to…
N-linked glycosylation is an important post translational modification, and the changes in N-glycan patterns are known to be associated with various human diseases. The study of N-glycans is crucial for the safety and efficacy of biotherapeutics. Tandem mass spectrometry (MS/MS) is a popular method in glycomics where glycans are identified via their mass to charge (m/z) and fragment ions. However, glycans exist as isomers arising from linkage,…
Ion mobility spectrometry-mass spectrometry has emerged as an orthogonal and complementary analytical technique to liquid chromatography-tandem mass spectrometry in omics-based analyses. Carbohydrate-containing molecules, such as human milk oligosaccharides and glycolipids, are notoriously difficult to characterize, largely owing to their high degrees of isomeric heterogeneity. Thus, new analytical methodologies are required to improve the…
The sequencing of intact proteins within a mass spectrometer enables the profiling of post-translational modification (PTM) crosstalk but is frequently hindered by convoluted spectra and the fact that tandem mass spectrometry (MS/MS) techniques often generate poor sequence coverages when applied to protein ions. Ion mobility spectrometry is a promising tool to overcome the complexity of these spectra by separating ions by their mass- and size-to…
The fundamental building blocks of life consist of lipids, carbohydrates, proteins, and nucleic acids which are assembled from small repeating monomer subunits. Specifically monosaccharides are the precursors of carbohydrates and amino acids are the building blocks of proteins. These two monomers are chiral (except glycine) and can exist in multiple stereochemical forms making their characterization complex.  While monosaccharides and amino…
Ion mobility-mass spectrometry (IM-MS) has emerged as a powerful analytical technique in the biological -omics over the last two decades, due to advantages in speed and separation capabilities. Despite its now widespread utility, the resolving power of many commercial IM platforms (~40-60) is often insufficient for resolution of structurally similar compounds such as stereoisomers. This presents a critical need for us to develop higher…
Recent innovations in speed, accuracy and sensitivity have established mass spectrometry (MS) based methods as a key technology for the analysis of complex mixtures. MS techniques are emerging as the analytical gold standard for the identification and characterization of molecular components with wide applications in forensic, environmental, and biomedical research.  My research group focuses on the development of emerging technologies for…
Over the past century, the rapidly rising rates of antibiotics resistance coupled with decreased new antibiotics on the markets has led to a global health crisis. In the United States alone, antibiotics resistant infections occur over 2.5 million times each year resulting in over 35,000 deaths.1 One bacterium of interest is Staphylococcus aureus (S. aureus) which is a gram-positive bacterium and one of the global leaders in antibiotic…