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- * Copper/Zinc superoxide dismutase signatures *
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-
- Copper/Zinc superoxide dismutase (EC 1.15.1.1) (SODC) [1] is one of the three
- forms of an enzyme that catalyzes the dismutation of superoxide radicals. SODC
- binds one atom each of zinc and copper. Various forms of SODC are known: a
- cytoplasmic form in eukaryotes, an additional chloroplast form in plants, an
- extracellular form in some eukaryotes, and a periplasmic form in prokaryotes.
- The metal binding sites are conserved in all the known SODC sequences [2].
-
- We derived two signature patterns for this family of enzymes: the first one
- contains two histidine residues that bind the copper atom; the second one is
- located in the C-terminal section of SODC and contains a cysteine which is
- involved in a disulfide bond.
-
- -Consensus pattern: [GA]-[IFAT]-H-[LIVF]-H-x(2)-[GP]-[SDG]-x-[STAGD]
- [The two H's are copper ligands]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: human complement receptor type 1.
-
- -Consensus pattern: G-[GN]-[SGA]-G-x-R-x-[SGA]-C-x(2)-[IV]
- [C is involved in a disulfide bond]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Note: these patterns will not detect proteins related to SODC, but which have
- lost their catalytic activity, such as Vaccinia virus protein A45.
-
- -Last update: December 1992 / Text revised.
-
- [ 1] Bannister J.V., Bannister W.H., Rotilio G.
- CRC Crit. Rev. Biochem. 22:111-154(1987).
- [ 2] Smith M.W., Doolittle R.F.
- J. Mol. Evol. 34:175-184(1992).
-