SynIXR linear permutations display changes in expression of essential genes and genes required for fast growth. (A) The relative normalized expression of 10 different genes (listed in Inset legend) was determined for 11 different synIXR permutations (YIR011C, YIR012W, YIR013C, YIR015W, YIR016W, YIR017W-A, YIR017C, YIR018W, YIR018C-A, YIR019C, YIR020C) compared with a strain encoding synIXR BAC. Expression of the same 10 genes was also determined relative to synIXR BAC for BY4741, which encodes native chromosome IX. (B) Fitness assays of permuted strains expressing YIR015 episomally [pYIR015W] or an empty vector. Shown here are 10-fold serial dilutions after 2 d growth on selective medium.