Catalyzes the NAD-dependent reduction of succinylglutamate semialdehyde into succinylglutamate (Probable). Also shows in vitro activity with decanal or succinic semialdehyde as the electron donor and NAD as the electron acceptor. No activity is detected with NADP as the electron acceptor. Therefore, is an aldehyde dehydrogenase with broad substrate specificity (PubMed:15808744). H2O + N-succinyl-L-glutamate 5-semialdehyde + NAD(+) = 2 H(+) + N-succinyl-L-glutamate + NADH decanal + H2O + NAD(+) = decanoate + 2 H(+) + NADH H2O + NAD(+) + succinate semialdehyde = 2 H(+) + NADH + succinate Amino-acid degradation; L-arginine degradation via AST pathway; L-glutamate and succinate from L-arginine: step 4/5. By nitrogen starvation, and arginine. Induced at stationary phase by sigma S. Belongs to the aldehyde dehydrogenase family. AstD subfamily.