The charge distribution in the cytoplasmic loop of subunit C of the F1F0 ATPase is a determinant for YidC targeting.
YidC is a member of the Oxa1 family of proteins that facilitates the membrane insertion of a subset of inner membrane proteins in Escherichia coli. YidC acts as an insertase for membrane insertion of subunit c of the F(1)F(0) ATP synthase (F(0)c), but the requirements for substrate recognition have remained unclear. Here, we have analyzed the role of the charged aminoacyl residues in F(0)c in YidC targeting and membrane insertion. Binding experiments demonstrate that F(0)c is targeted directly to YidC without the presence of a stable lipid surface-bound intermediate. Positive charges in the cytoplasmic loop of F(0)c are important determinants for YidC binding and subsequent membrane insertion. These data support a model in which F(0)c binds directly to YidC prior to its membrane insertion.
Kol
Stefan
S
Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and the Zernike Institute of Advanced Materials, University of Groningen, Haren, The Netherlands.
Nouwen
Nico
N
Driessen
Arnold J M
AJ
D019943:Amino Acid Substitution; D025243:Bacterial Proton-Translocating ATPases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology* / Q000235:genetics; D004926:Escherichia coli / Q000201:enzymology*; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D011485:Protein Binding / Q000502:physiology; D017433:Protein Structure, Secondary / Q000502:physiology; D017434:Protein Structure, Tertiary / Q000502:physiology; D013379:Substrate Specificity / Q000502:physiology
D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; C412443:YIDC protein, E coli; D025243:Bacterial Proton-Translocating ATPases