Catalyzes the synthesis of beta-citryl-L-glutamate and N-acetyl-L-aspartyl-L-glutamate. Beta-citryl-L-glutamate is synthesized more efficiently than N-acetyl-L-aspartyl-L-glutamate. ATP + citrate + L-glutamate = ADP + beta-citrylglutamate + H(+) + phosphate ATP + L-glutamate + N-acetyl-L-aspartate = ADP + H(+) + N-acetyl-L-aspartyl-L-glutamate + phosphate Binds 2 magnesium or manganese ions per subunit. N-acetyl-L-aspartyl-L-glutamate (NAAG) is the most abundant dipeptide present in vertebrate central nervous system (CNS). Beta-citryl-L-glutamate, a structural analog of NAAG, is present in testis and immature brain. May be produced at very low levels due to a premature stop codon in the mRNA, leading to nonsense-mediated mRNA decay. Belongs to the RimK family. Extended N-terminus.