Adam Barb, PhD
Biochemistry, Biophysics & Molecular Biology
Iowa State University
2214 Mol Bio
Ames, IA 50011-3260
My laboratory seeks to describe how immune system activation is tuned by carbohydrate chains (glycans) attached to proteins. This research direction seeks to identify novel disease therapies by studying the effect of molecular structure perturbations on immune cell responses. Our primary target is immunoglobulin G (IgG), a circulatory protein expressed to recognize foreign particles and initiate an immune response by activating Fcg Receptors. The structure of a glycan attached to Asn297 of the IgG Fragment crystallizable (Fc) domain influences the strength of the body’s response. Certain forms of this glycan are particularly prevalent in patients with autoimmune disorders, notably rheumatoid arthritis, though it is unclear why. These same glycan forms also perturb the Fc – Fcg Receptor interaction, though a biophysical mechanism linking the Fc glycan and immune activation has not yet been described. We use a wide variety of techniques, including: solution nuclear magnetic resonance spectroscopy, mass spectrometry, enzyme assays, mammalian and bacterial protein expression, as well as cell-based assays of macrophage and natural killer cell activation.
We are also interested in designing enzymes to accept non-native substrates. Enzymes of the polyketide synthesis machinery are being explored for their ability to accept substrate analogs with added chemical functionality. This effort is funded by the Center for BioRenewable Chemicals (www.cbirc.iastate.edu).
B.S. Purdue University
M.S. North Carolina State University
Ph.D. Duke University