Taurine-conjugated bile salts

Effect of pH. The effect of pH on the deoxycholate series of bile salts in 0.15N NaCl at 20° and 36°C. is summarized in Figure 8. Solutions of free and glycine conjugated bile salts were studied between pH 9.2 and their precipitation pH (NaDC == 6.95, NaGDC = 4.9). Taurine conjugates were studied between pH 10 and 1.6. 

Cysteine Mercaptopyruvic acid Cysteamine, taurine3 Cysteamine is a component of Co A Taurine is a component of conjugated bile salts... 

Bile acids are usually conjugated in amide linkage with the amino acid glycine or taurine, giving bile salts. The cholic acid conjugates with glycine and taurine are called glycocholate and taurocholate, respectively. 

Taurine Cysteine Liver Conjugated bile salts... 

In humans as in animals the primary bile acids are converted in various ways, and more than 25 different secondary bile acids have been identified in human feces. Deoxycholate and lithocholate stand out because they are found in large quantities. These secondary bile acids are derived from cholate and chenodeoxycholate through 7-dehydroxylation by enzymes of colonic bacteria. In man, primary and secondary bile salts are all conjugated to two amino acids, taurine and glycine, and thus the amounts of free bile salts are very small. Conjugated bile salts... 

The number of moles of bile salt necessary to solubilize one mole of bile acid in solution is also shown in Fig. 26. As the amount of conjugated bile salt increases in the mixture, the ratio of bile salt needed to carry one mole of bile acid in a clear micellar solution decreases steadily until the mixture contains 60% or more NaTC, when the ratio becomes fixed between 5 and 5.5 1. When the bile salt in the mixture is predominantly NaC, three times the amount of bile salt is necessary to carry" free bile acids in solution than when the predominant bile salt is the taurine conjugate. 

Mammalian bile contains sodium salts of conjugated bile acids, e.g. glycocholic acid and taurocholic acid, in which cholic acid is combined (amide linkage) with glycine and taurine respectively. 

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