Calf intestinal adenosine deaminase

FIGURE 16.8 (a) Phosphoglycolohydroxamate is an analog of the enediolate transition state of the yeast aldolase reaction, (b) Purine riboside, a potent inhibitor of the calf intestinal adenosine deaminase reaction, binds to adenosine deaminase as the 1,6-hydrate. The hydrated form of purine riboside is an analog of the proposed transition state for the reaction. 

All the multiple forms of calf intestinal adenosine deaminase as well as those of calf thymus, calf thymocytes, and human erythrocytes and lymphocytes are inactivated by this reagent. ... 

LVIII. Deamination of adenosine analogs with calf intestine adenosine deaminase, Biochim. Biophys. Acta 338 512 (1974). 

The susceptibilities of some of these fluorinated purine nucleosides to the action of enzymes are now described. In contrast to the inertness of the 2 -deoxy-2 -fluoro- and 3 -deoxy-3 -fluorocytidine analogs 739, 744, and 821 towards cytidine deaminase, the adenosine compounds 867, 883, and 906 are readily deaminated - by the adenosine deaminase in erythrocytes and calf intestine, but the resulting (deaminated) inosine compounds (from 867 and 883), as well as 888, are highly resistant - to cleavage by purine nucleoside phosphorylase (to give hypoxanthine base for the first two). The reason was discussed. Both 867 and 883 can form the 5 -triphosphates, without deamination, in human erythrocytes or murine sarcoma cells in the presence of 2 -deoxycoformycin, an adenosine deaminase inhibitor, but... 

Adenosine Deaminase Origin calf intestinal mucosa Fluka... 

Adenosine Deaminase Origin calf intestine Roche Diagnostics Adenosine Deaminase... 

Brady TC, O Connell W. A purification of adenosine deaminase from the superficial mucosa of calf intestine. Biochem Biophys Acta 1962 62 216-229. 

Adenosine deaminase from calf intestinal mucosa, the most widely studied enzyme, hydrolytically deaminates, in addition to adenosine, some other natural and synthetic nucleosides and also dehalogenates 6-halopurine ribosides. Many studies have been carried out to define the contribution of purine and ribose moieties in the binding of substrate and to help prepare effective inhibitors of the enzyme. - ... 

Adenosine deaminase (0.5-200 itM), purified from calf intestinal mucosa, in 0.2 M sodium phosphate at pH 8, containing 10% dimethyl sulfoxide (v/v), is treated at 37° in the dark with 9-(p-bromoacetamido-benzyl) adenine (0.01-5 mAf). The alkylating reagent is added dissolved in dimethyl sulfoxide. When necessary, the pH of the reaction mixture is maintained constant by addition of 1.0 A NaOH. At intervals 5-10 / samples are removed and diluted in 0.1 M sodium phosphate at pH 7.5 adenosine deaminase activity is measured. The enzyme activity is determined by the method of Kalckar with adenosine as substrate by following the decrease in absorbance at 265 nm in 0.1 Af sodium phosphate at pH 7.5. 

Adenosine deaminase converts adenosine and deoxyadenosine to the corresponding hypoxanthine derivatives (25). The enzyme is widely distributed and has been partially purified (25) from calf intestinal mucosa (26-28). 

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