Carrier protein that bears the covalently bound substrates for arginine and lysine biosynthesis; bound L-glutamate is sequentially converted to L-ornithine, while bound alpha-aminoadipate (AAA) is sequentially converted to L-lysine. Amino-acid biosynthesis; L-lysine biosynthesis via AAA pathway. Amino-acid biosynthesis; L-arginine biosynthesis. Monomer. Formation of an isopeptide bond between the gamma-carboxyl group of the C-terminal glutamate and the amino group of alpha-aminoadipate (AAA) is catalyzed by LysX. The bound AAA is then converted to L-lysine in a series of reactions catalyzed by LysZ, LysY and LysJ. Release of the product L-lysine is catalyzed by LysK. Formation of an isopeptide bond between the gamma-carboxyl group of the C-terminal glutamate and the amino group of L-glutamate is catalyzed by ArgX. The bound substrate is then sequentially converted to ornithine which is eventually converted to L-arginine (PubMed:23434852). Cells lacking this gene require arginine and lysine for growth.