that generate modifications of the codon usage are written in lowercase letters; The CACC sequence included at the beginning of some oligos is a requirement for cloning in the GatewayH- compatible vector pENTRTM/D-TOPOH. (DOC) Table S2 Plasmids generated by cloning of PCR prod- ucts into commercial blunt-ended plasmids. ALA1 no TT: modified ALA1 gene in which a predicted transcription termina- tion signal has been deleted; yeALA1: modified ALA1 gene in which a predicted transcription termination signal has been deleted and several codons codifying for arginine have been substituted to match the yeast preferred codon usage (see Materials and Methods and FigureS2). In some cases, the final PCR products have been generated by overlapping PCR. In these cases, the subsequent PCR amplification rounds are named PCR1 (gegneration of overlapping fragments) and PCR2 (amplification of the full-length final product). Letters A to E in PCR1 refer to the References 1. 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