Sucrose solubilizers

Hydrolysis and Other Reactions.—Continuing earlier studies Bull. Chem. Soc. Japan, 1976, 49, 1059), Japanese workers have now examined the hydrolysis of sucrose solubilized in benzene by a reversed micelle formed from dodecyl-benzenesulphonic acid. An enhancement factor of 400 (relative to aqueous hydrochloric acid) was observed, while ethanesulphonic acid showed only slight effect. It was tentatively concluded that the enhancement is related to the formation and stability of reversed micelles. Other workers have examined the acid-catalysed hydrolysis of sucrose at different hydrochloric acid concentrations and postulate a change of mechanism at 5.68 mol 1. ... 

Garti, N., Aserin, A., and Fanun, M., Non-ionic sucrose esters microemulsions for food applications. Part 1. Water solubilization. Colloid Surface A, 164, 27, 2000. 

ATPase also catalyzed a passive Rb -Rb exchange, the rate of which was comparable to the rate of active Rb efflux. This suggested that the K-transporting step of H,K-ATPase is not severely limited by a K -occluded enzyme form, as was observed for Na,K-ATPase. Skrabanja et al. [164] also described the reconstitution of choleate solubilized H,K-ATPase into phosphatidylcholine-cholesterol liposomes. With the use of a pH electrode to measure the rate of H transport they observed not only an active transport, which is dependent on intravesicular K, but also a passive H exchange. This passive transport process, which exhibited a maximal rate of 5% of the active transport process, could be inhibited by vanadate and the specific inhibitor omeprazole, giving evidence that it is a function of gastric H,K-ATPase. The same authors demonstrated, by separation of non-incorporated H,K-ATPase from reconstituted H,K-ATPase on a sucrose gradient, that H,K-ATPase transports two protons and two ions per hydrolyzed ATP [112]. 

Solubilization and Partial Purification of Cytochrome P-450 from Hepatic Microsomes of Male, DBA-Pretreated Little Skates. Washed hepatic microsomes (3) from the livers of 10 skates were suspended in 0.25 M sucrose and frozen under nitrogen (-5 to -10°) at the Maine laboratory. They were then packed in dry ice and transported to NIEHS, Research Triangle Park, NC, within 14 days of preparation and were stored at -62°C until use. Microsomes... 

Solubilize samples in either 2x SDS sample buffer containing sucrose or glycerol but not urea. Heat to 37°C for 15 min. 

Cells of E. coli B are found to produce significant amounts of this enzyme only after the stage of rapid exponential growth has ceased. All attempts to enhance or to repress its synthesis by altering the composition of the growth medium or conditions of culture have been unsuccessful. Glutaminase is not released when the cells are converted to protoplasts in isotonic sucrose, but the enzyme is solubilized upon lysis of the protoplasts. Strain W also possesses the enzyme, but no extensive screening of related species has been done. 

Principle In this procedure erythrocytes are treated with Triton X-100 which is reported to solubilize the membrane lipid leaving the underlying cytoskeletal network intact. The cyto-skeletons are separated from cytosolic components, Triton and solubilized lipid by centrifugation through a sucrose solution. The high salt concentration of the sucrose solution ensures the removal of residual lipid and integral membrane proteins from the cytoskeletal network. 

Chloroplast ATP synthase is a well-defined complex which may be solubilized fi om thylakoid membranes by treatment with octylglucoside and cholate and purified by ammonium sulphate fi actionation and sucrose density gradient centrifugation [140]. The complex is composed of two assemblies of polypeptides CFj, a peripheral membrane complex, which may be washed fi-om thylakoid membranes with EDTA and which shows latent ATPase activity, and CFg, the intrinsic membrane sector, which translocates protons across the thylakoid membrane. 

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