Development and atomic structure of a new fluorescence-based sensor to probe heme transfer in bacterial pathogens.

Heme is the most abundant source of iron in the human body and is actively scavenged by bacterial pathogens during infections. Corynebacterium diphtheriae and other species of actinobacteria scavenge heme using cell wall associated and secreted proteins that contain Conserved Region (CR) domains. Here we report the development of a fluorescent sensor to measure heme transfer from the C-terminal CR domain within the HtaA protein (CR2) to other hemoproteins within the heme-uptake system.