Translocators proteoliposomes

A quantitative reconstitution approach was used to gain information as to the subunit composition of the -ATPase molecule [25]. Proteoliposomes prepared from asolectin and purified, radiolabeled ATPase molecules obtained by a freeze-thaw procedure similar to that of Dufour et al. [34] were shown to catalyze ATP hydrolysis-driven proton translocation, as indicated by the extensive quenching of aminochloromethoxyacridine fluorescence that occurs upon the addition of MgATP to the proteoliposomes, and the reversal of this quenching induced by... 

Unphosphorylated functioning according to Fig. 5 catalyzes facilitated diffusion of mannitol across the membrane. The same process has been reported for purified II reconstituted in proteoliposomes [70]. The relevance of this activity in terms of transport of mannitol into the bacterial cell is probably low, but it may have important implications for the mechanism by which E-IIs catalyze vectorial phosphorylation. It would indicate that the transmembrane C domain of Il is a mannitol translocating unit which is somehow coupled to the kinase activity of the cytoplasmic domains. We propose that the inwardly oriented binding site which is in contact with the internal water phase (Ecyt Mtl, see Fig. 5) is the site from where mannitol is phosphorylated when transport is coupled to phosphorylation. Meehan-... 

The roles of lipids in proton translocation can also be studied with FgFj proteoliposomes. Fluidity and acidity of the phospholipids are required for proton translocation [129,130]. 

The transport speed of the transporter is equivalent to the ion flux of the ion channel. However, the ion flux of channels does not exhibit saturation with an increase of the ion concentration and it is larger by orders of magnitude than the transport speed of transporters. The ion flux is directly proportional to the ion stream. The basis of the function of translocators is membrane-enclosed compartments cells, organelles, vesicles, or proteoliposomes (prolis). Prolis and liposomes play a role in purification and reconstitution of translocators. The following sections are dedicated to them. 

Solubilize the translocator protein prove by reconstituting the function in proteoliposomes... 

---