Bacterial aerobic respiratory chain (BARC) (BARC)

The bacterial aerobic respiratory chain is a sophisticated assembly of membrane-associated enzymes and electron carriers that orchestrate the transfer of electrons from metabolic substrates to molecular oxygen (Bott & Niebisch, 2003, J Mol Microbiol Biotechnol) [1]. This electron flow is coupled to the translocation of protons across the bacterial cytoplasmic membrane, establishing a proton motive force (PMF) that drives the synthesis of ATP via the F1Fo-ATP synthase (Cook et al., 2014, Adv Microb Physiol) [2]. Unlike the relatively uniform mitochondrial respiratory chain in eukaryotes, bacterial systems exhibit significant diversity and modularity, often containing multiple primary dehydrogenases and terminal oxidases to adapt to varying environmental conditions (Spero et al., 2015, Nat Rev Microbiol) [3]. This structural divergence provides a strategic advantage for drug discovery, allowing for the design of inhibitors that selectively target bacterial bioenergetics without disrupting human mitochondrial function (Bald & Koul, 2010, Curr Opin Microbiol) [4]. Therapeutic agents such as bedaquiline, which inhibits ATP synthase, and telacebec, which targets the cytochrome bc1 complex, have demonstrated the clinical efficacy of disrupting this pathway, particularly in treating Mycobacterium tuberculosis (Pethe et al., 2013, Nat Med) [5]. Consequently, the respiratory chain is a vital target for developing new antibiotics to combat antimicrobial resistance (Hards & Cook, 2018, Drug Resist Updat) [6]. Targeting this system can lead to rapid depletion of cellular energy and subsequent cell death in both actively growing and dormant bacterial populations. The flexibility of the bacterial respiratory chain also presents challenges, as bacteria may employ alternative pathways to bypass specific inhibited complexes.

Other names

Bacterial electron transport chainBacterial oxidative phosphorylation systemBacterial respiratory machineryBacterial ETC

Inhibition of ATP synthase, inhibition of the cytochrome bc1 complex (QcrB), inhibition of type II NADH dehydrogenase (NDH-2), and disruption of the proton motive force.