The copper-deprivation stimulon of comprises proteins for biogenesis of the actinobacterial cytochrome - supercomplex.

Aerobic respiration in involves a cytochrome - supercomplex with a diheme cytochrome , which is the only -type cytochrome in this species. This organization is considered as typical for aerobic Actinobacteria. Whereas the biogenesis of heme-copper type oxidases like cytochrome has been studied extensively in α-proteobacteria, yeast, and mammals, nothing is known about this process in Actinobacteria.

The h-region of twin-arginine signal peptides supports productive binding of bacterial Tat precursor proteins to the TatBC receptor complex.

The twin-arginine translocation (Tat) pathway transports folded proteins across bacterial membranes. Tat precursor proteins possess a conserved twin-arginine (RR) motif in their signal peptides that is involved in their binding to the Tat translocase, but some facets of this interaction remain unclear. Here, we investigated the role of the hydrophobic (h-) region of the trimethylamine -oxide reductase (TorA) signal peptide in TatBC receptor binding and We show that besides the RR motif, a minimal, functional h-region in the signal peptide is required for Tat-dependent export in Furthermore, we identified mutations in the h-region that synergistically suppressed the export defect of a TorA[KQ]-30aa-MalE Tat reporter protein in which the RR motif was replaced with a lysine-glutamine pair.