Thiamin triphosphate structure

Chemical structure (Figure 6). Pyrimidine and thiazole moiety linked by methylene bridge - phos-phorylated forms thiamine monophosphate (TMP), thiamine diphosphate (TDP), thiamine triphosphate (TTP). 

Figure 5.4 Structural formulae of thiamin phosphate esters. At present, five natural thiamin phosphate derivatives have been described thiamin monophosphate (ThMP) thiamin diphopshate (ThDP) thiamin triphosphate (ThTP) adenosine thiamin diphosphate (AThDP) and adenosine thiamin triphosphate (AThTP). Catalytic intermediates, such as for instance a-hydroxyethyl thiamine diphosphate formed by the action of yeast pyruvate decarboxylase (EC 4.1.1.1), are not considered here.

The structures of the phosphate esters of thiamine are also shown in Figure 1. Thiamine monophosphate (TMP), thiamine pyrophosphate (TPP), and thiamine triphosphate (TTP) are commonly found in organisms. About 80% to 90% of the total thiamine content in cells is TPP, the coenzyme form of thiamine. In some animal tissues, especially pig skeletal muscle (2) and chicken white skeletal muscle (3), TTP is present in an extremely high amount (70% to 80% of total thiamine—i.e., thiamine plus thiamine phosphate esters). However, TTP has no coenzyme activity. Thiamine pyrophosphate in the dried state is stable for several months when stored at a low temperature in the dark. In solution, TPP is unstable and partially decomposes to TMP and/or thiamine when stored for several months at pH 5 and 38°C. However, TPP in solution at pH 2 to 6 and at 0°C is... 

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