Partial purification and properties of XXXX liver polynucleotide phosphorylase.

@entity1025 @entity5688 @entity840 @entity29594 @entity2827 @entity4337
1. @entity29594 phosphorylase has been isolated and partially purified from crude preparations of @entity840 liver nuclei. 2. The enzyme is particulate and associated with RNA and lipids characteristic of membranes. 3. It has phosphorolysis and exchange activities, but the latter may be due to a contaminating enzyme. 4. The phosphorolysis activity is dependent on bivalent cations, preferably @entity1025 , has a pH optimum between 8.6 and 9.2 and is inhibited by @entity4337 and @entity2827 . 5. The enzyme catalyses phosphorolysis of poly A, poly C, poly U, rRNA and tRNA. Poly G is only phosphorolysed to a very small extent and DNA is not a substrate. 6. The enzyme appears to lack @entity5688 polymerization activity.
