Commensal gut bacteria employ de-chelatase HmuS to harvest iron from heme

ABSTRACT: Iron is essential for almost all organisms, which have evolved different strategies for ensuring a sufficient supply from their environment and store it in different forms, including heme in animals. The hmu operon, primarily found in Bacteroidota and ubiquitous in gastrointestinal tract metagenomes of healthy humans, encodes proteins involved in heme acquisition. Here, we provide direct physiological, biochemical, and structural evidence for the anaerobic removal of iron from heme by HmuS, a membrane-bound, NADH-dependent de-chelatase that deconstructs heme to protoporphyrin IX (PPIX) and Fe(II). Heme can serve as the sole iron source for the model gastrointestinal bacterium Bacteroidetes thetaiotaomicron, when active HmuS is present. Heterologously expressed HmuS was isolated with bound

SUBMITTER: Arnab Kumar Nath 

PROVIDER: S-SCDT-10_1038-S44318-025-00563-5 | biostudies-other |

REPOSITORIES: biostudies-other