H2O + L-glutamate 5-semialdehyde + NAD(+) = 2 H(+) + L-glutamate + NADH Amino-acid degradation; L-proline degradation into L-glutamate; L-glutamate from L-proline: step 2/2. Expression is sigma L dependent and induced by arginine. Belongs to the aldehyde dehydrogenase family. RocA subfamily.