FMN binding to the PNPOx-like scaffold of PM0042 from Pasteurella multocida facilitates electron transfer in heme degradation

The HugZ/HutZ family has been shown to degrade heme in the presence of ascorbic acid. However, its inability to utilize canonical cytochrome P450 reductase has raised questions regarding its physiological role as a true heme oxygenase. PM0042 from Pasteurella multocida, a member of the HugZ/HutZ family, belongs to the pyridoxamine 5'-phosphate oxidase (PNPOx) family, which utilizes FMN as a cofactor. In this study, we examined the role of FMN in heme-degradation activity. Fluorescence analysis r