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Lysophosphatidic acid (LPA) is a phospholipid that acts as an extracellular signaling molecule and activates the family of lysophosphatidic acid receptors (LPA1-6). These G protein-coupled receptors (GPCRs) are broadly expressed and are particularly important in development as well as in the nervous, cardiovascular, reproductive, gastrointestinal, and pulmonary systems. Here, we report on a photoswitchable analogue of LPA, termed AzoLPA, which contains an azobenzene photoswitch embedded in the acyl chain. AzoLPA enables optical control of LPA receptor activation, shown through its ability to rapidly control LPA-evoked increases in intracellular Ca2+ levels. AzoLPA shows greater activation of LPA receptors in its light-induced cis-form than its dark-adapted (or 460 nm light-induced) trans-form. AzoLPA enabled the optical control of neurite retraction through its activation of the LPA2 receptor.

Sphingosine-1-phosphate (S1P) plays important roles as a signaling lipid in a variety of physiological and pathophysiological processes. S1P signals via a family of G-protein-coupled receptors (GPCRs) (S1P1-5) and intracellular targets. Here, we report on photoswitchable analogs of S1P and its precursor sphingosine, respectively termed PhotoS1P and PhotoSph. PhotoS1P enables optical control of S1P1-3, shown through electrophysiology and Ca2+ mobilization assays. We evaluated PhotoS1P in vivo, where it reversibly controlled S1P3-dependent pain hypersensitivity in mice. The hypersensitivity induced by PhotoS1P is comparable to that induced by S1P. PhotoS1P is uniquely suited for the study of S1P biology in cultured cells and in vivo because it exhibits prolonged metabolic stability compared to the rapidly metabolized S1P. Using lipid mass spectrometry analysis, we constructed a metabolic map of PhotoS1P and PhotoSph. The formation of these photoswitchable lipids was found to be light dependent, providing a novel approach to optically probe sphingolipid biology.

In this study, a computational molecular orbital theory experiment was implemented in a first-semester honors general chemistry course. Students used the GAMESS (General Atomic and Molecular Electronic Structure System) quantum mechanical software (as implemented in ChemBio3D) to optimize the geometry for various small molecules. Extended Huckel calculations were also performed using ChemBio3D, and the results were then used to develop molecular orbital theory descriptions of the bonding. Both quantitative (posttest results) and qualitative (online student evaluations) data were used in the assessment of student learning. (Contains 2 tables and 4 figures.)

Results demonstrate that an area in the amino terminus of the actin-binding protein villin is the site of phosphorylation involving amino acid residues 1 to 261 constituting five phosphorylation sites. Furthermore, phosphorylation inhibits actin-nucleating function of the protein.

Research was conducted to test whether amide-linked oligomers of neuraminic acid could be prepared with water soluble higher order constructs. The oligomers were conjugated to Epsilon-amino caproic acid to describe membrane-bound conformations while solid-phase methods were utilized to improve result efficiency. Results indicated the importance of tetramer in ordered secondary structures. They also showed that end amide was exposed to solvent and underwent rapid exchange.

The Educational Materials for Organic Chemistry Project (EMOC) developed Web-based learning materials, which were accessible by students enrolled in a variety of undergraduate organic chemistry courses at a major midwestern […]