3-[(3-コラミドプロピル)ジメチルアンモニオ]-1-プロパンスルホナート

化学的特性White crystalline powder. CHAPS may be synthesized from cholic acid and is zwitterionic due to its quaternary ammonium and sulfonate groups; it is structurally similar to certain bile acids, such as taurodeoxycholic acid and taurochenodeoxycholic acid. It is sparingly soluble or insoluble in aqueous solution due to their native hydrophobicity.

使用CHAPS is a zwitterionic nondenaturing detergent for solubilizing membrane proteins. It is used in the laboratory to dissolve biological macromolecules such as proteins. It acts as a non-denaturing solvent used in purification of membrane proteins. It is also useful in conjunction with nonionic detergents like Triton X-100. Further, it is used as a non-denaturing zwitterionic detergent for membrane biochemistry.

一般的な説明CHAPS is a stabilizing agent that can be used to prevent aggregation, precipitation or proteolysis of proteins in solution.

純化方法Triturate this zwitterionic detergent (~50g) with MeOH (200ml), then triturate it with Me2CO (500mL), collect it by vacuum filtration and dry it thoroughly at ~20o. Recrystallise it at 0o from absolute MeOH followed by drying in vacuo to constant weight. It should give one spot with RF 0.32 by TLC on silica gel G in 95% MeOH/5% NH4OH and visualized with iodine vapour; the tertiary amine precursor has RF 0.40. It has low UV absorption (1% in H2O: A280nm is 0.029 and A260nm is 0.035), and the CMC (critical micellar concentration) is 8mM. It is soluble in H2O, MeOH, Me2SO but insoluble in Me2CO, MeCN, hexane, toluene and xylene. [Hjelmeland et al. Anal Biochem 130 72 1983, Matuo et al. Methods Enzymol 198 155 1991.] CHAPSO (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate betaine) [82473-24-3] M 630.89, m 184-196o, [ ] D +19o (c 2, H2O), pKEst (1) ~<2 (acidic), pKEst(2) ~9 (basic). Dissolve this zwitterionic detergent (~ 60g) in 40% aqueous MeOH and stir it with the mixed-bed ion-exchange resin RG-501 x 8 (100g, Bio-Rad) until the pH of the supernatant is ~ 7. Filter off the resin and evaporate the filtrate to dryness under reduced pressure. Check for homogeneity by TLC on silica gel G in 95% MeOH/5% NH4OH and visualize the spot with iodine vapour (see CHAPS above). [Hjelmeland et al. Anal Biochem 130 72 1983, Matuo et al. Methods Enzymol 198 155 1991.]