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- *********************************************************
- * Bacterial histone-like DNA-binding proteins signature *
- *********************************************************
-
- Bacteria synthesize a set of small, usually basic proteins of about 90
- residues that bind DNA and are known as histone-like proteins [1,2]. The exact
- function of these proteins is not yet clear but they are capable of wrapping
- DNA and stabilizing it from denaturation under extreme environmental
- conditions. The sequence of a number of different types of these proteins is
- known:
-
- - The HU proteins, which, in Escherichia coli, are a dimer of closely related
- alpha and beta chains and, in other bacteria, can be dimer of identical
- chains. HU-type proteins have been found in a variety of eubacteria,
- cyanobacteria and archaebacteria, and are also encoded in the chloroplast
- genome of some algae [3].
- - The integration host factor (IHF), a dimer of closely related chains which
- seem to function in genetic recombination as well as in translational and
- transcriptional control [4] in enterobacteria.
- - The bacteriophage sp01 transcription factor 1 (TF1) which selectively binds
- to and inhibits the transcription of hydroxymethyluracil-containing DNA,
- such as sp01 DNA, by RNA polymerase in vitro.
-
- As a signature pattern for this family of proteins, we use a twenty residue
- sequence which includes three perfectly conserved positions. According to the
- tertiary structure of one of these proteins [5], this pattern spans exactly
- the first half of the flexible DNA-binding arm.
-
- -Consensus pattern: [GS]-F-x(2)-[LIVMF]-x(4)-[RKEQA]-x(2)-[RST]-x-[GA]-x-[KN]-
- P-x-T
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
- -Last update: June 1994 / Pattern and text revised.
-
- [ 1] Drlica K., Rouviere-Yaniv J.
- Microbiol. Rev. 51:301-319(1987).
- [ 2] Pettijohn D.E.
- J. Biol. Chem. 263:12793-12796(1988).
- [ 3] Wang S., Liu X.-Q.
- Proc. Natl. Acad. Sci. U.S.A. 88:10783-10787(1991).
- [ 4] Friedman D.I.
- Cell 55:545-554(1988).
- [ 5] Tanaka I., Appelt K., Dijk J., White S.W., Wilson K.S.
- Nature 310:376-381(1984).
-