Catalyzes the condensation of the acetyl group of acetyl-CoA with 3-methyl-2-oxobutanoate (2-oxoisovalerate) to form 3-carboxy-3-hydroxy-4-methylpentanoate (2-isopropylmalate) (By similarity). Alpha-isopropylmalate synthase leuA leu1 RDEVVRGRDVVISTHTHDDLGMATANALAGVENGAGQIECTINGIGERAGNCALEEVVMALYVRRDWYKAYTRINTREIYRVSRLVERYTGMPVPPNKAIVGDNAFAHESGIHQDGVIKHRATYEIMDAELIGRRPAVLVLGKHSGRAAFKKALEDLGYKDLSEEEVKKLFARFKEIAEKKGPLSAEELQALVESEREPTSHFFQLEHVQFFSGSGLLPTATVKVKTPDGERLATHTGDGPVDAVYKAIQEAIGLRPELELYRVEAITGSTEALGQVTVRLRLGELQAVGVGVSPDIIEASALAFLDAAGKLASGRATRHPPSIEEVHRGV 2-isopropylmalate synthase (Fragment) 331 Alpha-IPM synthase LEU1_THETH