Identification and validation of reference genes to study the gene expression in Gluconacetobacter diazotrophicus grown in different carbon sources using RT-qPCR

► rpoC and dnaG were highly unstable in bacteria cultivated in medium with different carbon sources. ► rho, rpoD and 23SrRNA were the best reference genes to study bacteria gene expression. ► 23SrRNA was highly expressed and should be used with care to avoid the target gene expression error.