Stable Metal:Amorphous Carbon Substrates for Combined SPR and MS Analysis of Bioaffinity Interactions

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

The Analytical and Surface Chemistry Program in the Division of Chemistry, with co-funding from the Biomolecular Systems Cluster in the Division of Molecular and Cellular Biosciences, is supporting Profs. Lloyd Smith and collaborators Helen Blackwell and Michael Shortreed at the University of Wisconsin to study the nature and significance of interactions between molecules in biological systems. Specifically, they are examining the "language" that bacteria use for communication involving diffusible small molecules (or "autoinducers") perceived by cognate protein receptors. Bacteria use this chemical language to assess local population densities in a process known as "quorum sensing" which enables regulation of critical processes both harmful and beneficial to their plant host. Methods to control bacterial quorum sensing in plant-associated bacteria would have a major impact on agricultural science, because >50% of crop disease worldwide is caused by quorum sensing-regulated behaviors in bacteria. Further, molecules that inhibit bacterial quorum sensing represent an entirely new class of anti-infectives that could have immediate impact on human health. The work aims to develop new technologies for the elucidation of this complex communication network - a fundamental scientific advance. The focus is to create a more general platform for the multiplex analysis of bioaffinity interactions and to develop and apply this platform in the context of bacterial quorum sensing. The platform combines three powerful capabilities: (1) label-free measurements of bioaffinity interactions; (2) a novel substrate, which permits versatile and stable biomolecule attachment; and (3) mass spectrometric (MS) analysis capability to identify unknown ligands binding to the surface. This combination of three powerful and synergistic capabilities in a single system will provide a tool of unprecedented utility for the analysis of bioaffinity interactions. The research groups involved are interdisciplinary, training researchers at many different stages of their education. Current collaborations involve over 20 different groups on campuses worldwide, plus two companies, and span the biological and physical sciences. In conjunction with the research, the PIs engage in interdisciplinary undergraduate research training; graduate student professional development through the Delta program (the UW implementation of the NSF Center for the Integration of Research, Teaching and Learning program); professional development for junior and senior high-school instructors through regular lectures by UW faculty; and a day-long hands-on science experience for high-school AP-chemistry students.