April 16, 2020

A research article from the Ragsdale lab is an Editors' Pick in the Journal of Biological Chemistry

The heme regulatory motifs of heme oxygenase-2 contribute to the transfer of heme to the catalytic site for degradation

Model of Fe3+-heme binding to HO2 and transfer of Fe3+-heme between binding sites in the core and the tail of the protein.

Heme regulatory motifs (HRMs) are present in many proteins that are involved in diverse biological functions. The C-terminal tail region of human heme oxygenase-2 (HO2) contains two HRMs whose cysteine residues form a disulfide bond; when reduced, these cysteines are available to bind Fe3+-heme. Heme binding to the HRMs occurs independently of the HO2 active site in the core of the protein, where heme binds with high affinity and is degraded to biliverdin. Members of the Ragsdale lab and their collaborators characterized the protein-mediated transfer of heme between the HRMs and the HO2 core and used their results to propose a model in which HRM-bound Fe3+-heme is readily transferred to the catalytic site for degradation to facilitate turnover, but can also equilibrate between the sites to maintain heme homeostasis.

Editors’ Picks represent the top-rated papers published in JBC across the field of biological chemistry, as determined by the Associate Editors, Editorial Board Members and other referees, and are accompanied by additional content summarizing the new findings and featuring the scientists involved. First author Angela Fleischhacker, Ph.D., an assistant research scientist in the Biological Chemistry Department, is featured in a profile in the journal. Congratulations to Angela, Steve, and their coauthors for their publication and its selection as an Editors' Pick!

Read the author profile HERE.
Read the JBC article HERE.