Predicted expression of the of <i>lux</i> genes before and after codon-optimization.

GENSCAN translation prediction scores for expression of wild-type (wt) and codon-optimized (co) lux genes in a mammalian host cell (http://genes.mit.edu). Predicted start position is the predicted nucleotide sequence location for initiation based on the transcription of the nucleotide gene sequence. The predicted truncation in length of the wild-type luxE gene was due to the presence of a non-mammalian preferred start codon in the original gene sequence. Exon score interpretation: 0–50 weak, 50–100 moderate, >100 strong. Additional length in the codon-optimized version of the frp gene is the result of additional nucleotides added to introduce new restriction enzyme sites for improved cloning efficiency. N/A - not applicable.