Heme Binding to HupZ with a C-Terminal Tag from Group A Streptococcus
| Autor: | Tapiwa Chiura, Ian Davis, Zehava Eichenbaum, Aimin Liu, Jiafeng Geng, Piotr J. Mak, Ankita J Sachla, Francis K. Yoshimoto, Jiasong Li, Ephrahime S Traore |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
heme stacking
Heme binding Stereochemistry Streptococcus pyogenes Recombinant Fusion Proteins Resonance Raman spectroscopy Pharmaceutical Science Heme Article Analytical Chemistry lcsh:QD241-441 03 medical and health sciences chemistry.chemical_compound Bacterial Proteins lcsh:Organic chemistry resonance Raman spectroscopy Drug Discovery medicine Physical and Theoretical Chemistry 030304 developmental biology iron acquisition chemistry.chemical_classification 0303 health sciences Chemistry 030302 biochemistry & molecular biology Organic Chemistry Mutagenesis metal-binding proteins Streptococcus Heme oxygenase multimeric heme complexation Enzyme protein quaternary structure Chemistry (miscellaneous) GAS Molecular Medicine Ferric Protein quaternary structure EPR medicine.drug Protein Binding |
| Zdroj: | Molecules, Vol 26, Iss 549, p 549 (2021) Molecules Volume 26 Issue 3 |
| ISSN: | 1420-3049 |
| Popis: | HupZ is an expected heme degrading enzyme in the heme acquisition and utilization pathway in Group A Streptococcus. The isolated HupZ protein containing a C-terminal V5-His6 tag exhibits a weak heme degradation activity. Here, we revisited and characterized the HupZ-V5-His6 protein via biochemical, mutagenesis, protein quaternary structure, UV&ndash vis, EPR, and resonance Raman spectroscopies. The results show that the ferric heme-protein complex did not display an expected ferric EPR signal and that heme binding to HupZ triggered the formation of higher oligomeric states. We found that heme binding to HupZ was an O2-dependent process. The single histidine residue in the HupZ sequence, His111, did not bind to the ferric heme, nor was it involved with the weak heme-degradation activity. Our results do not favor the heme oxygenase assignment because of the slow binding of heme and the newly discovered association of the weak heme degradation activity with the His6-tag. Altogether, the data suggest that the protein binds heme by its His6-tag, resulting in a heme-induced higher-order oligomeric structure and heme stacking. This work emphasizes the importance of considering exogenous tags when interpreting experimental observations during the study of heme utilization proteins. |
| Databáze: | OpenAIRE |
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