Summer research with Rizk

The biochemistry lab of Professor Shahir Rizk (pictured second from the right) is rarely quiet during the academic year – and it is even busier this summer with three undergraduate research students. Biology major Pierre-Emmanuel N'Guetta (pictured far right) is continuing work on a project to develop a biosensor for glyphosate, the main ingredient in the herbicide RoundUp. He began the project last year with the help of a SMART grant, and now he has a protein-based fluorescent biosensor that can detect micromolar amounts of the pollutant. He is currently trying to use this biosensor to test for glyphosate in soil samples.

Biochemistry major Winnie Ihano (pictured far left) is funded by the LSAMP program. Her goal is to express and purify mutants of the human enzyme adenosine deaminase. This enzyme is important in the degradation of the nucleotide adenosine. Individuals with mutations in this enzyme suffer from Severe Combined Immune Deficiency (SCID), a fatal disease that leaves its victims susceptible to all kinds of infections. Winnie is generating recombinant forms of these mutants found in SCID patients and trying to isolate them in order to characterize them in the lab.

Biology major Chris Stewart (pictured second from the left) is also working on adenosine deaminase. His work, funded by a SMART grant, is concerned with engineering antibody fragments that can bind to the active form of the enzyme. By recognizing the active form of the enzyme, we hope that these antibody fragments can be used to convert the less active mutants found in SCID patients into active enzymes with the hopes of reversing the effect of the disease (at least in the test-tube).

In addition to his research with these three students, Rizk has been busy with other projects. He attended the first Regional Cottrell Scholar meeting in April at the University of Illinois, Urbana-Champagne, at the invitation of St. Mary’s chemist Dr. Kathryn Haas, a recent Cottrell Scholar who had previously taught at IU South Bend for a year before teaching at St. Mary’s College. The Cottrell foundation supports chemistry, physics, and astronomy professors who are developing innovative research and teaching programs at their institutions through their Cottrell Scholars Program. The meeting included former Cottrell scholars and members of their research groups as well as hopeful future Cottrell Scholars (such as Rizk).The meeting included presentations and roundtable discussions on research and teaching methods. Rizk had the chance to present a poster on his research in protein engineering and his teaching strategies that use discussion sections to introduce STEM majors to current events in science policy and new research developments through assigned readings and guest lectures by practicing scientists from academia and industry. Rizk was invited to submit a full application for the Cottrell Scholar program in July and we wish him success in this endeavor. 

Summer research with Marmorino

No goggles for these students. Chemistry majors Conor McGee and Christian Moreno are spending the summer working on quantum mechanical problems with Professor Matt Marmorino. Their work is a combination of theory and computation - not a single chemical will be harmed in their research. Instead they'll be making good use of Mathematica to run number-crunching programs that they are very busy writing.

McGee is funded by the Carolyn & Lawrence Garber Summer Research Scholarship which is awarded each summer to just one chemistry or biochemistry major. He is testing (on the hydrogen atom) some old, but underutilized, techniques to calculate bounds to the energy and position moments for atoms and molecules. These techniques require information that is typically not available for traditional trial wave functions, but Conor is introducing an adjustable defect into the wave functions that, while reducing the quality of the wave function, allows for atypical information about the system to be calculated and utilized. If the approach works well on the hydrogen atom, then it should also work on more complex atoms and molecules too.

Moreno's work  is supported by one of several Louis Stokes Alliances for Minority Participation  (LSAMP) grants provided to STEM students at IU South Bend. He is testing simple quantum mechanical models to duplicate the known trends (such as atomic radius, ionization energy, and ground-state electron configuration) in the periodic table. The hydrogenic model, which ignores electron-electron repulsion is too simple to reproduce the trends; but the commonly-used Hartree-Fock method, which incorporates repulsion, is too complex for the beginning science student to fully appreciate and lacks a [rigorous] simple orbital interpretation.  Moreno is testing a model based on first-order perturbation theory that partly mimics the hydrogen model in simplicity, but incorporates at least some of the repulsion to reproduce the periodic trends. He's hoping that he doesn't need to deal with the repulsion in its full glory, because that is quite a task.