Abstract:
:In vitro, polynucleotide phosphorylase of Escherichia coli can both synthesize RNA by using nucleotide diphosphates as precursors and exonucleolytically degrade RNA in the presence of inorganic phosphate. However, because of the high in vivo concentration of inorganic phosphate in exponentially growing cells, it has been assumed that the enzyme works exclusively as an exonuclease. Here we demonstrate that, contrary to this prediction, polynucleotide phosphorylase not only synthesizes long, highly heteropolymeric tails in vivo, but also accounts for all of the observed residual polyadenylylation in poly(A) polymerase I deficient strains. In addition, the enzyme is responsible for adding the C and U residues that are found in poly(A) tails in exponentially growing cultures of wild type E. coli.
journal_name
Proc Natl Acad Sci U S Aauthors
Mohanty BK,Kushner SRdoi
10.1073/pnas.220295997keywords:
subject
Has Abstractpub_date
2000-10-24 00:00:00pages
11966-71issue
22eissn
0027-8424issn
1091-6490pii
220295997journal_volume
97pub_type
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