Supramolecular organizations in the aerobic respiratory chain of Escherichia coli.
The organization of respiratory chain complexes in supercomplexes has been shown in the mitochondria of several eukaryotes and in the cell membranes of some bacteria. These supercomplexes are suggested to be important for oxidative phosphorylation efficiency and to prevent the formation of reactive oxygen species. Here we describe, for the first time, the identification of supramolecular organizations in the aerobic respiratory chain of Escherichia coli, including a trimer of succinate dehydrogenase. Furthermore, two heterooligomerizations have been shown: one resulting from the association of the NADH:quinone oxidoreductases NDH-1 and NDH-2, and another composed by the cytochrome bo(3) quinol:oxygen reductase, cytochrome bd quinol:oxygen reductase and formate dehydrogenase (fdo). These results are supported by blue native-electrophoresis, mass spectrometry and kinetic data of wild type and mutant E . coli strains.
Eco-Bio, Instituto de Investigação Científica Tropical, Av. da República, Oeiras, Portugal.
Pedro M F
PM
Sousa
Sara T N
ST
Silva
Brian L
BL
Hood
Nuno
N
Charro
João N
JN
Carita
Fátima
F
Vaz
Deborah
D
Penque
Thomas P
TP
Conrads
Ana M P
AM
Melo
D000332:Aerobiosis; D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism; D004579:Electron Transport; D004586:Electrophoresis; D048168:Escherichia coli K12 / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D008969:Molecular Sequence Data; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D012995:Solubility