FIGURE 5.

ssSPT chimera reveal that residues 11–26 specify acyl-CoA selectivity. A, schematic represents ssSPT chimera. B, microsomes were prepared from lcb1Δlcb2Δtsc3Δ mutant yeast expressing hLCB1, hLCB2a, and either ssSPTa (a), ssSPTb (b), a chimera that contains the first 27 residues of ssSPTa and the last 49 residues of ssSPTb (ab), a chimera that contains the first 54 residues of ssSPTb and the last 14 residues of ssSPTa (ba), or a chimera in which residues 27–54 of ssSPTa were replaced by residues 27–54 from ssSPTb (aba). SPT activities were measured using C16- and C18-CoA as substrate.