Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.4.4 (adenosine deaminase)
 5,136 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In Bacillus cereus purine ribonucleosides and deoxyribonucleosides share a common inducible catabolic pathway, leading to the formation of ribose-5-P or deoxyribose-5-P respectively inside the cell, while the purine ring remains in the external medium. Both ribo- and deoxyribonucleosides are inducers of adenosine deaminase, inosine-guanosine phosphorylase and phosphopentomutase, the enzymes of the catabolic pathway. We now show that deoxyribonucleosides, but not ribonucleosides, induce the aldolase specific for deoxyribose-5-P (2-deoxy-D-ribose-5-phosphate acetaldehyde lyase, EC 4.1.2.4), thus allowing the sugar moiety of exogenous deoxyribonucleosides to be utilized as an energy source.
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PMID:Induction of deoxyribose-5-phosphate aldolase of Bacillus cereus by deoxyribonucleosides. 643 5

The present work describes an assay which is highly specific for ribose-5-phosphate. The method is based on the following three-stage enzymatic conversion: (1) ribose 5-phosphate in equilibrium ribose 1-phosphate (phosphopentomutase); (2) ribose 1-phosphate + adenine in equilibrium adenosine + Pi (adenosine phosphorylase); (3) adenosine + H2O----inosine + NH3 (adenosine deaminase). Ribose 5-phosphate may be determined either directly following the change in absorbance at 265 nm associated with the conversion of adenine to inosine, or radioenzymatically by measuring the radioactivity of inosine formed from [8-14C]adenine, after chromatographic separation of the nucleoside on polyethyleneimine-cellulose. The spectrophotometric assay was used to follow ribose 5-phosphate formation and ribose 1-phosphate consumption catalyzed by phosphopentomutase. Further, the ability of alkaline phosphatase, 5'-nucleotidase and crude extract of Bacillus cereus cells to act on ribose 5-phosphate was tested. The radioenzymatic assay was proved useful in determining the levels of ribose 5-phosphate in rat tissues.
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PMID:Spectrophotometric and radioenzymatic determination of ribose-5-phosphate. 653 May 7