TABLE 1.
Mutation | Location in Tg | Effect on CPS or CPSII |
---|---|---|
Ec C269A | Tg C345 | Abolishes GATase activity |
Ec G359F | Tg G435 | Ammonia leaks, uncoupling GATase & CPS |
Ha T456A | Tg T533 | Abolishes MAPK activation |
Ec E761A | Tg E1316 | Abolishes ornithine activation and UMP repression |
Ec H781K | Tg H1336 | Reduces CPS activity, ornithine activation, and UMP repression |
Ec T974A | Tg T1530 | Reduces ornithine activation, IMP activation, and UMP repression |
Ha S1345A | Tg T1530 | Reduces PRPP activation |
Ec T1042A | Tg T1649 | Reduces ornithine binding |
Escherichia coli (Ec); Hamster (Ha); T. gondii (Tg)
See text for references and Supplemental Figure for alignments. Table 1 identifies the location of residues in T. gondii CPSII that correspond to residues previously examined in mutagenesis studies in either E. coli or Hamster CPS enzymes.