<i>rpoB</i> and <i>efp</i> are stable candidate reference genes for quantitative real-time PCR analysis in <i>Saccharopolyspora spinosa</i>

Spinosad (spinosyn A and spinosyn D), the secondary metabolite produced by Saccharopolyspora spinosa, is a potent insecticide with low effects on environment mammals. Strategies such as metabolic engineering, mutagenesis fermentation process optimization have been employed for its production enhancement. Quantitative real-time polymerase chain reaction(qRT-PCR) one of preferred methods evaluation gene transcript levels, whose accuracy sensitivity depend normalization using optimal reference genes. However, no single universally appropriate all strains under various conditions. In this study, transcriptional stability 35 candidate genes, including 23 traditionally used genes 12 novel identified in S. spinosa homologous species, was analysed ATCC 49460 spinosad high-yield strain S3-3 three phases. The these assessed statistical algorithms, geNorm, NormFinder BestKeeper. overall rankings suggested that rpoB efp were most stable they may be promising further study measurement expression levels target involved biosynthetic spinosad.