Graduate Student Crystal Bolden
Receives Young Investigator Award

Graduate Student Crystal Bolden was a recipient of the Young Investigator Award at the 22nd Annual Meeting for the Society for Free Radical Biology and Medicine. The Young Investigator Award is presented to students and postdoctoral fellow members based on a submitted research abstract and the presentation of the work at the Society's Annual Meeting as judged by members of SFRBM's Awards–Junior Committee.

Crystal is a PhD Candidate in Molecular Medicine and Translational Science at the Wake Forest University School of Medicine and works with Physics Professor Dr. Daniel Kim–Shapiro. The abstract for her poster titled "Reactions of Nitrosopersulfide with Heme Proteins" is below.

To evaluate the bioavailability of NO, one must consider its interaction with other gaseous molecules such as hydrogen sulfide (H₂S). When NO or NO⁺ react with excess H₂S they form several intermediates including a stable NO donating intermediate, nitrosopersulfide (SSNO^-). The abundance and prominence of iron–containing proteins throughout the human body brings additional relevance to the interaction of ferrous– and ferric–iron containing proteins with SSNO^-. Study of the reactions of SSNO^- with heme proteins can also provide information about the stability and spontaneous reactivity of this species. We have used electron paramagnetic resonance and UV–Vis spectroscopy to study the reactions of SSNO^- with heme proteins. Iron–nitrosyl hemoglobin (HbNO) is formed when SSNO^- is reacted with deoxyhemoglobin(dHb) and deoxy methemoglobin, suggesting NO formaton from SSNO^-. When SSNO^- is reacted with oxygenated hemoglobin, no methemoglobin (metHb) is formed. Taken together, these data confirm release of NO. However, the yields of HbNO in reactions of SSNO^- with dHb in these experiments are much less than when SSNO^- is reacted with metHb. These data suggest that the ferric iron in metHb potentiates SSNO^- reactivity. Furthermore, the absence of methemoglobin formation from reactions of SSNO^- and oxyHb, the diminished HbNO yield from metHb and SSNO^- under O₂, and the presence of MbNO from reactions of metMb and SSNO^- under N₂, but not from NO donor suggest a vacant heme is required to obtain nitrosyl species, which suggests a direct reaction between the SSNO^- and heme.