TY  - JOUR
A1  - Lemaire, Olivier N.
A1  - Infossi, Pascale
A1  - Chaouche, Amine Ali
A1  - Espinosa, Leon
A1  - Leimkühler, Silke
A1  - Giudici-Orticoni, Marie-Therese
A1  - Mejean, Vincent
A1  - Iobbi-Nivol, Chantal
T1  - Small membranous proteins of the TorE/NapE family, crutches for cognate respiratory systems in Proteobacteria
JF  - Scientific reports
N2  - In this report, we investigate small proteins involved in bacterial alternative respiratory systems that improve the enzymatic efficiency through better anchorage and multimerization of membrane components. Using the small protein TorE of the respiratory TMAO reductase system as a model, we discovered that TorE is part of a subfamily of small proteins that are present in proteobacteria in which they play a similar role for bacterial respiratory systems. We reveal by microscopy that, in Shewanella oneidensis MR1, alternative respiratory systems are evenly distributed in the membrane contrary to what has been described for Escherichia coli. Thus, the better efficiency of the respiratory systems observed in the presence of the small proteins is not due to a specific localization in the membrane, but rather to the formation of membranous complexes formed by TorE homologs with their c-type cytochrome partner protein. By an in vivo approach combining Clear Native electrophoresis and fluorescent translational fusions, we determined the 4: 4 stoichiometry of the complexes. In addition, mild solubilization of the cytochrome indicates that the presence of the small protein reinforces its anchoring to the membrane. Therefore, assembly of the complex induced by this small protein improves the efficiency of the respiratory system.
Y1  - 2018
U6  - https://doi.org/10.1038/s41598-018-31851-2
SN  - 2045-2322
VL  - 8
PB  - Nature Publ. Group
CY  - London
ER  -