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- ********************************************************
- * Prokaryotic zinc-dependent phospholipase C signature *
- ********************************************************
-
- Bacillus cereus expresses a phosphatidylcholine hydrolyzing phospholipase C
- (EC 3.1.4.3) (PLC) which is a monomeric protein of 245 amino-acid residues
- that binds three zinc ions [1]. This PLC is highly similar to the following
- proteins:
-
- - Alpha-toxin from Clostridium perfringens and bifermentans which are also
- zinc-dependent phospholipases C [2].
- - Lecithinase C from Listeria monocytogenes [3].
-
- In Bacillus cereus, there are nine residues known to be involved in binding
- the zinc ions: 5 His, 2 Asp, 1 Glu and 1 Trp. These residues are all conserved
- in the Clostridium alpha-toxin.
-
- As a signature pattern for this family of enzymes, we selected a conserved
- region of 11 residues that contains three of the zinc ligands: a histidine
- involved in binding the first zinc ion, an aspartic acid which binds both the
- first and the third zinc ion, and a histidine which binds the second zinc ion.
-
- -Consensus pattern: H-Y-x-[GT]-D-[LIVM]-[DNS]-x-P-x-H-[PA]-x-N
- [The two H's and the D bind zinc]
- -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] Hough E., Hansen L.K., Birknes B., Jynge K., Hansen S., Hordvik A.,
- Little C., Dodson E., Derewenda Z.
- Nature 338:358-360(1989).
- [ 2] Titball R.W., Rubidge T.
- FEMS Microbiol. Lett. 68:261-266(1990).
- [ 3] Vazquez-Boland J.-A., Kocks C., Dramsi S., Ohayon H., Geoffroy C.,
- Mengaud J., Cossart P.
- Infect. Immun. 60:219-230(1992).
-