Primary Submission Contact

Robert Clark

Faculty Sponsor

Robert Clark

Faculty Sponsor Email Address


Arts and Sciences



Document Type

Poster Presentation


Fall 10-28-2016


CooA, a CO-sensing heme protein, acts as a transcriptional activator of CO-metabolizing proteins in bacteria such as Rhodospirillum rubrum and Carboxydothermus hydrogenoformans through sequence-specific DNA binding. Previous research indicated a reduced iron center and CO gas were necessary for CooA to achieve its active conformation and bind DNA. To determine if other reaction conditions facilitate CooA activation, the role of pH on CooA function was tested. Specifically, a fluorescence anisotropy assay was employed to measure possible Fe(III) CooA DNA binding from pH 3 - 12. Interestingly, CooA was observed to bind DNA without CO at acidic conditions, with optimal binding observed at pH ~3. These results are discussed in light of the normal CO-dependent activation mechanism of CooA proteins.

Biographical Information about Author(s)

Brian Weaver is a senior biochemistry major at Valparaiso University. He has worked on the CooA project with Dr. Robert Clark since the summer of 2015. This project has garnered Brian's interest because it demonstrates how the interaction of metal centered chemistry with amino acid chains can provide impressive specificity and function. In addition, he has worked on metalloprotein research related to photosynthesis in Dr. John Golbeck's lab at Pennsylvania State University. His future plans include attending graduate school to continue his study of structure and function of metalloproteins.

Additional Presentation Information

Wall Poster