Structure and function of subunit a of the ATP synthase of Escherichia coli.

Journal article

The structure of subunit a of the Escherichia coli ATP synthase has been probed by construction of more than one hundred monocysteine substitutions. Surface labeling with 3-N-maleimidyl-propionyl biocytin (MPB) has defined five transmembrane helices, the orientation of the protein in the membrane, and information about the relative exposure of the loops connecting these helices. Cross-linking studies using TFPAM-3 (N-(4-azido-2,3,5,6-tetrafluorobenzyl)-3-maleimido-propionamide) and benzophenone-4-maleimide have revealed which elements of subunit a are near subunits b and c. Use of a chemical protease reagent, 5-(-bromoacetamido)-1,10-phenanthroline-copper, has indicated that the periplasmic end of transmembrane helix 5 is near that of transmembrane helix 2.

Authors: Vik, S; Ishmukhametov, R

• Journal: Journal of bioenergetics and biomembranes
• Volume: 37
• Issue: 6
• Pages: 445-449
• Publication date: 2005-12-01
• DOI: 10.1007/s10863-005-9488-6
• EISSN: 1573-6881
• ISSN: 0145-479X
• Language: English
• Keywords: Membrane Proteins; Bacterial Proton-Translocating ATPases; Escherichia coli Proteins; Protein Conformation; Mitochondrial Proton-Translocating ATPases; Mutagenesis, Site-Directed; Cysteine; Protein Subunits