Recent advances in bacterial heme protein biochemistry

Abstract

Recent progress in genetics, fed by the burst in genome sequence data, has led to the identification of a host of novel bacterial heme proteins that are now being characterized in structural and mechanistic terms. The following short review highlights very recent work with bacterial heme proteins involved in the uptake, biosynthesis, degradation, and use of heme in respiration and sensing.

Mutations in hemG Mediate Resistance to Salicylidene Acylhydrazides, Demonstrating a Novel Link between Protoporphyrinogen Oxidase (HemG) and Chlamydia trachomatis Infectivity

“…5). This gene encodes protoporphyrinogen oxidase (PPO or HemG), an enzyme that catalyzes the second to last step of heme biosynthesis (46,57). Chlamydia codes for all components for the biosynthesis of heme (47), an important cofactor of peroxidases, catalases, sensor molecules, and cytochromes (46).…”

In vitro heme biotransformation by the HupZ enzyme from Group A streptococcus

“…Pathogenic bacteria often tap into the heme reservoir to overcome the severe iron scarcity, which they encounter during infection. These pathogens use elaborate systems to scavenge heme from host hemoproteins and transport it into the bacterial cell (Benson and Rivera 2013;Mayfield et al 2011;Nobles and Maresso 2011;Pishchany and Skaar 2012). A few mechanisms allow bacteria to retrieve iron from heme.…”

The evolutionary appearance of signaling motifs in PGRMC1

“…For instance PGRMC1 association with the mitotic spindle could represent a universal eukaryotic MAPR trait, or may represent a metazoan, vertebrate, or mammalian innovation. Sterol or heme synthesis are ancestral traits of all eukaryotes, and are indeed also widespread in bacteria (9,10). The involvement of PGRMC1 and its yeast homolog Dap1 in the conversion of lanosterol to cholesterol (animals) or ergosterol (yeast) (11) argues strongly for an ancestral eukaryotic role of MAPR proteins in sterol production, and perhaps also in heme synthesis based upon a role proposed by Ghosh et al for yeast (7) and by Piel et al in mammals (6).…”