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- ************************************************************
- * Acyltransferases ChoActase / COT / CPT family signatures *
- ************************************************************
-
- A number of eukaryotic acetyltransferases can be, on the basis of sequence
- similarities, grouped together into a family. These enzymes are:
-
- - Choline o-acetyltransferase (EC 2.3.1.6) (ChoAcTase), an enzyme that
- catalyzes the biosynthesis of the neurotransmitter acetylcholine [1].
- - Carnitine o-acetyltransferase (EC 2.3.1.7) [2].
- - Peroxisomal carnitine octanoyltransferase (EC 2.3.1.-) (COT), a fatty acid
- beta-oxidation pathway enzyme which is involved in the transport of medium-
- chain acyl-coenzyme A's from peroxisome to mitochondria [3].
- - Mitochondrial carnitine palmitoyltransferases I and II (EC 2.3.1.21) (CPT),
- enzymes involved in fatty acid metabolism and transport [4].
-
- These three enzymes share many regions of sequence similarities. As signature
- patterns we selected two of these regions. The first one, located in the
- N-terminal section of these enzymes is characterized by the presence of three
- [LIVM]-P dipeptides. The second region, located in the central part of these
- enzymes is characterized by the conservation of a number of charged residues
- including an histidine which probably plays a crucial role in the catalytic
- mechanism [5].
-
- -Consensus pattern: L-P-x-[LIVMP]-P-[LIVM]-P-x-[LIVM]-x-[DENQAS]-[ST]-[LIVM]-
- x(2)-Y
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
-
- -Consensus pattern: R-[FYW]-x-D-[KA]-[ST]-[LIVMFY]-x-[LIVMFY](2)-x(3)-[DNS]-
- [GS]-x(6)-[ED]-H
- [H is a probable 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] Berrard S., Brice A., Lottspeich F., Braun A., Barde Y.-A., Mallet J.
- Proc. Natl. Acad. Sci. U.S.A. 84:9280-9284(1987).
- [ 2] Kispal G., Tomcsanyi T., Sumegi B., Bock I., Gajdos G., Dietmayer K.,
- Sandor A.
- J. Biol. Chem. 268:1824-1829(1993).
- [ 3] Chatterjee B., Song C.S., Kim J.-M., Roy A.K.
- Biochemistry 27:9000-9006(1988).
- [ 4] Esser V., Britton C.H., Weis B.C., Foster D.W., McGarry J.D.
- J. Biol. Chem. 268:5817-5822(1993).
- [ 5] Schmalix W., Bandlow W.
- J. Biol. Chem. 268:27428-27439(1993).
-