Close proximity of a cytoplasmic loop of subunit a with c subunits of the ATP synthase from Escherichia coli.
AuthorsZhang D, Vik SB
JournalJ Biol Chem
PubMed ID12525480
'Interactions between subunit a and the c subunits of the Escherichia coli ATP synthase are thought to control proton translocation through the F(o) sector. In this study cysteine substitution mutagenesis was used to define the cytoplasmic ends of the first three transmembrane spans of subunit a, as judged by accessibility ... More
The Escherichia coli PII signal transduction protein regulates the activities of the two-component system transmitter protein NRII by direct interaction with the kinase domain of the transmitter module.
AuthorsPioszak AA, Jiang P, Ninfa AJ
JournalBiochemistry
PubMed ID11063581
The PII signal transduction protein regulates the transcription of nitrogen-regulated genes by controlling the kinase and phosphatase activities of NRII. We used a cross-linking approach to study the interaction of the T-loop of the PII protein with NRII. Cross-linking of PII to NRII required ATP and 2-ketoglutarate, allosteric effectors known ... More
The gamma subunit of the Escherichia coli F1-ATPase can be cross-linked near the glycine-rich loop region of a beta subunit when ADP + Mg2+ occupies catalytic sites but not when ATP + Mg2+ is bound.
AuthorsAggeler R, Cai SX, Keana JF, Koike T, Capaldi RA
JournalJ Biol Chem
PubMed ID8407913
A mutant of the Escherichia coli F1-ATPase, gamma S8C, has been reacted with a novel bifunctional reagent, N-maleimido-N'-(4-azido-2,3,5,6-tetrafluorobenzamido) cystamine (TFPAM-SS1). Modification of Cys-8 via the maleimide, followed by photolysis to convert the azido group to a reactive nitrene, led to cross-linking of the gamma subunit to a beta subunit. When ... More