AAK_AKii-LysC-BS: Amino Acid Kinase Superfamily (AAK), AKii; this CD includes the N-terminal catalytic aspartokinase (AK) domain of the lysine-sensitive aspartokinase isoenzyme AKII of Bacillus subtilis 168, and the lysine plus threonine-sensitive aspartokinase of Corynebacterium glutamicum, and related sequences. In B. subtilis 168, the regulation of the diaminopimelate (Dap)-lysine biosynthetic pathway involves dual control by Dap and lysine, effected through separate Dap- and lysine-sensitive aspartokinase isoenzymes. The B. subtilis 168 AKII is induced by methionine, and repressed and inhibited by lysine. Although Corynebacterium glutamicum is known to contain a single aspartokinase isoenzyme type, both the succinylase and dehydrogenase variant pathways of DAP-lysine synthesis operate simultaneously in this organism. In this organism and other various Gram-positive bacteria, the DAP-lysine pathway is feedback regulated by the concerted action of lysine and theronine. Also included in this CD are the aspartokinases of the extreme thermophile, Thermus thermophilus HB27, the Gram-negative obligate methylotroph, Methylophilus methylotrophus AS1, and those single aspartokinases found in Pseudomons, C. glutamicum, and Amycolatopsis lactamdurans. B. subtilis 168 AKII, and the C. glutamicum, Streptomyces clavuligerus and A. lactamdurans aspartokinases are described as tetramers consisting of two alpha and two beta subunits; the alpha (44 kD) and beta (18 kD) subunits formed by two in-phase overlapping polypeptides.
Jiyao W et al.(2023). "The conserved domain database in 2023.",