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Domains of Escherichia coli primase: functional activity of a 47-kDa N-terminal proteolytic fragment.

ABSTRACT: Endoproteinase Asp-N cleaves the 581-amino acid Escherichia coli primase (65,564 Da) into several major fragments. One of these, a 47-kDa fragment containing the complete N terminus and the first 422 amino acids of primase, is capable of primer RNA (pRNA) synthesis in the G4oric/single-stranded DNA binding protein/primase pRNA synthesis system. A cloned 398-amino acid N-terminal fragment of primase can also synthesize pRNA. The sizes of the pRNA synthesized by these N-terminal fragments, however, are smaller than those synthesized by intact primase, suggesting that the C-terminal region of primase plays a role in processivity or regulation of pRNA synthesis. Primase mutants with the last 10 and 40 C-terminal amino acids deleted synthesize pRNA as wild-type primase, indicating that any regulatory sequences must be internal to the C terminus of primase.

SUBMITTER: Sun W

PROVIDER: S-EPMC45251 | biostudies-other | 1994 Nov

REPOSITORIES: biostudies-other

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Domains of Escherichia coli primase: functional activity of a 47-kDa N-terminal proteolytic fragment.

Sun W W Tormo J J Steitz T A TA Godson G N GN

Proceedings of the National Academy of Sciences of the United States of America 19941101 24

Endoproteinase Asp-N cleaves the 581-amino acid Escherichia coli primase (65,564 Da) into several major fragments. One of these, a 47-kDa fragment containing the complete N terminus and the first 422 amino acids of primase, is capable of primer RNA (pRNA) synthesis in the G4oric/single-stranded DNA binding protein/primase pRNA synthesis system. A cloned 398-amino acid N-terminal fragment of primase can also synthesize pRNA. The sizes of the pRNA synthesized by these N-terminal fragments, however ...[more]

PMID: 7526396

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