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- * Adenylosuccinate synthetase active site *
- *******************************************
-
- Adenylosuccinate synthetase (EC 6.3.4.4) [1] plays an important role in purine
- biosynthesis, by catalyzing the GTP-dependent conversion of IMP and aspartic
- acid to AMP. Adenylosuccinate synthetase has been characterized from various
- sources ranging from Escherichia coli (gene purA) to vertebrate tissues. In
- vertebrates, two isozymes are present - one involved in purine biosynthesis
- and the other in the purine nucleotide cycle.
-
- It has been shown [2] that, in the Escherichia coli enzyme, a lysine residue
- is essential for the enzyme's activity. This lysine and the region around it
- are conserved in known adenylosuccinate synthetase sequences and can be used
- as a signature pattern.
-
- -Consensus pattern: G-I-G-P-x-Y-x(2)-K-x(2)-R
- [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: December 1991 / First entry.
-
- [ 1] Wiesmueller L., Wittbrodt J., Noegel A.A., Schleicher M.
- J. Biol. Chem. 266:2480-2485(1991).
- [ 2] Dong Q., Fromm H.J.
- J. Biol. Chem. 265:6235-6240(1990).
-