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- * Bacteriophage-type RNA polymerase family active site signatures *
- *******************************************************************
-
- Many forms of RNA polymerase (EC 2.7.7.6) are known. Most RNA polymerases are
- multimeric enzymes, but there is a family of single chain polymerases, which
- are evolutionary related, and which, except for two known exceptions,
- originate from bacteriophages. The RNA polymerases that belong to this family
- are [1]:
-
- - Podoviridae bacteriophages T3, T7, and K11 polymerase.
- - Bacteriophage SP6 polymerase.
- - Yeast mitochondrial polymerase (gene RPO41).
- - Polymerases encoded on mitochondrial linear DNA plasmids in various fungi
- and plants: Agaricus bitorquis pEM, Claviceps purpurea pClK1, Neurospora
- crassa Kalilo; Neurospora intermedia Maranhar and maize S-2).
-
- Two conserved aspartate and one lysine residue have been shown [2,3] to be
- part of the active site of T7 polymerase. We have used the regions around the
- first aspartate and around the lysine as signature patterns for this family of
- polymerases.
-
- -Consensus pattern: P-[LIVM]-x(2)-D-[GA]-[ST]-[AC]-[SN]-[GA]-[LIVMFY]-Q
- [D is the active site residue]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Consensus pattern: [LIVMF]-x-R-x(3)-K-x(2)-[LIVMF]-M-[PT]-x(2)-Y
- [K is the active site residue]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Last update: June 1994 / Text revised.
-
- [ 1] McAllister W.T., Raskin C.A.
- Mol. Microbiol. 10:1-6(1993).
- [ 2] Maksimova T.G., Mustayev A.A., Zaychikov E.F., Lyakhov D.L.,
- Tunitskaya V.L., Akbarov A.K., Luchin S.V., Rechinsky V.O., Chernov B.K.,
- Kochetkov S.N.
- Eur. J. Biochem. 195:841-847(1991).
- [ 3] Sousa R., Chung Y.J., Rose J.P., Wang B.-C.
- Nature 364:593-599(1993).
-