| Title | Purification and characterization of purine nucleoside phosphorylase (PNP) in micrococcus luteus |
|---|---|
| Author | Choi, Hye Seon * |
| Address | Department of Microbiology, Ulsan University |
| Bibliography | Journal of Microbiology, 34(1),82-89, 1996, |
| DOI | |
| Key Words | Purine nucleoside phosphorylase, Micrococcus luteus, inosine, guanosinem adenosine, 1-methylinosine, purification |
| Abstract | Purine nucleoside phosphorylase (PNP) was purified in Micrococcus luteus (M. luteus) using streptomycin sulfate and amomonium sulfate fractionation, three times by a Sephadex G-100 gel filtration and a DEAE-Sephadex A-50 ion exchange chromatography. The enzyme was purified 72 folds with a 11% recovery and showed a single band in a nondenaturing gel electrophoresis. The M. W. of PNP turned out to be 1.35 × 10^5 dalton in G-150 gel filtration chromatography. The stability of the enzyme was increased by treatment with both substrates, MgCI₂or CaCI₂, but not significantly kcal/mol. M. luteus PNP catalyzed the phosphorolysis of inosine, deoxyinosine, guanosine and deoxyguanosine with the Km value of 1.5 × 10^-3 M, 3.0 × 10^-3 M, 5.0 × 10^-4 M, respectively. The enzyme was reacted with adenosine, 1-methylnosine and 1-methylguanosine as substrates, which were shown to be poor substrates for mammalian enzyme. |
| Download PDF | Eng_340113_82-89p.pdf |