Detergency solubilization

Such solubilized protein-detergent complexes are the starting material for purification and crystallization. For some proteins, the addition of small amphipathic molecules to the detergent-solubilized protein promotes crystallization, probably by facilitating proper packing interactions between the molecules in all three dimensions in a crystal (Figure 12.2b). Therefore, many different amphipathic molecules are added in separate crystallization experiments until, by trial and error, the correct one is found. 

Radioiodinated derivatives have been prepared to define more closely the target site of a-conotoxins on the acetylcholine receptor (R. Myers, unpublished data). In membrane preparations from Torpedo electroplax, photoactivatable azidosalicylate derivatives of a-conotoxin GIA preferentially label the p and 7 subunits of the acetylcholine receptor. However, when the photoactivatable derivative is cross-linked to detergent solubilized acetylcholine receptor (AChR), only the 7 subunit is labeled. Since snake a-neurotoxins mainly bind to the a subunits of AChR and a-conotoxins compete directly with a-bungarotoxin, the cross-linking results above are both intriguing and problematic. 

Many different glycosyltransferase activities involved in higher plant wall biosynthesis have been identified in cell free membrane fractions, but in only a few cases has glycosyltransferase activity been retained in detergent-solubilized preparations, and in even fewer cases have any purified polypeptides been identified as plant cell wall glycosyltransferases (29,33). 

Crystallization of Ca -ATPase in detergent-solubilized. sarcoplasmic reticulum... 

Further advance toward a high-resolution structure of Ca -ATPase requires three-dimensional crystals of sufficient size and quality for X-ray diffraction analysis [179]. A prerequisite for the formation of three-dimensional crystals is the solubilization of the enzyme from its membrane environment by detergents [180,181]. Since the detergent-solubilized Ca -ATPase is notoriously unstable, the first task was to find conditions that preserve the ATPase activity of solubilized enzyme for several months. 

The Ca -ATPase microcrystals formed in detergent-solubilized sarcoplasmic reticulum in the presence of 20 mM Ca " and 20% glycerol contain highly ordered crystalline sheets of Ca -ATPase molecules, that associate into multilamellar stacks (Fig. 6) consisting frequently of more than 100 layers [156,183-185]. 

Figure 3. Size exclusion chromatography analysis of AP-trapped vs. detergent-solubilized FS2 core complexes.

The water-splitting activity of detergent-solubilized and AP-trapped PS2 reaction centers was measured using a Clark electrode. As shown in Figure 4, differences between the two types of samples were minimal, with a slight decrease of activity when the pH of the P-DM solution was shifted to pH 8 and a moderate increase following addition of A8-35, dilution below the CMC of p-DM and treatment with BioBeads. 

Figure 4. Oxygen evolving activity of AP-trapped v.v. detergent-solubilized PS2 core complexes.

Krogh-Hansen U, LeMarie M, Moller JV. The mechanism of detergent solubilization of liposomes and protein-containing membranes. Biophys J 1998 75 2932-2941. 

The systematic study of how detergents solubilize the viral proteins laid the basis for our understanding of how the viral particle is built. The... 

Uses. Anticorrosive agent chemical intermediate for the production of emulsifiers, detergents, solubilizers, cosmetics, drugs, and textile finishing agents... 

The structure and thermodynamics of formation of mixed micelles is of great theoretical interest. Micelles are also present and often integrally involved in practical processes. For example, in a small pore volume surfactant flooding process (sometimes called micellar flooding), the solution injected into an oil field generally contains 5-12 weight X surfactant (i) and the surfactant is predominately in micellar form in the reservoir water. In detergency, solubilization can be... 

In fact, several recent experiments suggest that the mechanism of detergent solubilization should be re-examined, and that if repeating... 

The final enzyme in the pathway, CMP-KDO transferase, the enzyme that catalyzes the transfer of KDO from CMP-KDO to the Lipid A acceptor has been studied in Mary Jane Osborn s laboratory. We have not further purified this enzyme nor studied its properties in detail. The in vitro reaction described by Munson et al. (15) utilized a detergent solubilized enzyme preparation to catalyze the transfer of two KDO residues to the Lipid A precursor. 

SOME MECHANISTIC INSIGHTS INTO GPCR ACTIVATION FROM DETERGENT-SOLUBILIZED TERNARY COMPLEXES ON BEADS... 

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