Function Switching and Regulation of a Multifunctional Enzyme

With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Professors Stefan Franzen and Reza Ghiladi of the North Carolina State University to study the conversion of pollutants to less harmful products. The conversion is done using naturally occurring enzymes found in a segmented worm that lives in shallow coastal waters. The project provides a better understanding of how we can use naturally occurring processes to create technologies for environmental restoration. The research also gives fundamental insight into how proteins can have more than one function in living organisms. The project provides outreach to middle school science classrooms with demonstrations, lectures, and lessons plans for teachers on the chemistry of life processes through the "Creating STARS" outreach initiative. Professors Franzen and Ghiladi also promote the mentoring of high school students in summer-long internships through Project SEED. The protein known as dehaloperoxidase-hemoglobin (DHP) is a recent example of a multi-functional protein that challenges many of the assumptions behind the structure-function correlation in enzymes. While structure is clearly related to function, Professors Franzen and Ghiladi are investigating whether structure uniquely defines function. Research on DHP suggests that structure does not uniquely define function, at least within the scope of the heme protein function. DHP was initially identified as a dual function protein capable of both oxygen transport and the enzymatic dehalogenation of halophenols as a natural function. DHP has been recently shown to also possess peroxygenase, oxidase, and oxygenase activities. TDHP represents an ideal platform for testing whether the structure-function paradigm too closely associates protein structure with a single function. It may be revealed that the classic view of protein structure may be too narrow to capture all functions a protein may possess. The focus of the research is a combined structural, spectroscopic and mechanistic (kinetics) study that elucidates the specific set of substrate/inhibitor interactions and dynamics changes for each of the four known functions of DHP.

With this award, the Chemistry of Life Processes Program in the Chemistry Division is funding Professors Stefan Franzen and Reza Ghiladi of the North Carolina State University to study the conversion of pollutants to less harmful products. The conversion is done using naturally occurring enzymes found in a segmented worm that lives in shallow coastal waters. The project provides a better understanding of how we can use naturally occurring processes to create technologies for environmental restoration. The research also gives fundamental insight into how proteins can have more than one function in living organisms. The project provides outreach to middle school science classrooms with demonstrations, lectures, and lessons plans for teachers on the chemistry of life processes through the "Creating STARS" outreach initiative. Professors Franzen and Ghiladi also promote the mentoring of high school students in summer-long internships through Project SEED. The protein known as dehaloperoxidase-hemoglobin (DHP) is a recent example of a multi-functional protein that challenges many of the assumptions behind the structure-function correlation in enzymes. While structure is clearly related to function, Professors Franzen and Ghiladi are investigating whether structure uniquely defines function. Research on DHP suggests that structure does not uniquely define function, at least within the scope of the heme protein function. DHP was initially identified as a dual function protein capable of both oxygen transport and the enzymatic dehalogenation of halophenols as a natural function. DHP has been recently shown to also possess peroxygenase, oxidase, and oxygenase activities. TDHP represents an ideal platform for testing whether the structure-function paradigm too closely associates protein structure with a single function. It may be revealed that the classic view of protein structure may be too narrow to capture all functions a protein may possess. The focus of the research is a combined structural, spectroscopic and mechanistic (kinetics) study that elucidates the specific set of substrate/inhibitor interactions and dynamics changes for each of the four known functions of DHP.