2-oxoglutarate + N(2)-acetyl-L-ornithine = L-glutamate + N-acetyl-L-glutamate 5-semialdehyde Amino-acid biosynthesis; L-arginine biosynthesis; N(2)-acetyl-L-ornithine from L-glutamate: step 4/4. Belongs to the class-III pyridoxal-phosphate-dependent aminotransferase family.