ACT domains found C-terminal to the catalytic domain of aspartokinase (AK; 4-L-aspartate-4-phosphotransferase)
This CD includes the first of two ACT domains found C-terminal to the catalytic domain of aspartokinase (AK; 4-L-aspartate-4-phosphotransferase). AK catalyzes the conversion of aspartate and ATP to aspartylphosphate and ADP, and is the first enzyme in the pathway of the biosynthesis of the aspartate family of amino acids, lysine, threonine, methionine, and isoleucine. This CD, includes the first ACT domain of the Escherichia coli (EC) isoenzyme, AKIII (LysC) and the Arabidopsis isoenzyme, asparate kinase 1, both enzymes monofunctional and involved in lysine synthesis, as well as the the first ACT domain of Bacillus subtilis (BS) isoenzyme, AKIII (YclM), and of the Saccharomyces cerevisiae AK (Hom3). Also included are the first ACT domains of the Methylomicrobium alcaliphilum AK, the first enzyme of the ectoine biosynthetic pathway. Members of this CD belong to the superfamily of ACT regulatory domains.