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curve composing pure RNA with six decimal dilutions, with

the highest concentration of 10 ng/μL while the lowest con-

centration of 10−^5 ng/μL. Based on three replicate experi-

ments, efficiencies of these two assays are above 95%. To reflect

the CFU of M. marinum from each sample, correlation

between CFU and the amount of total RNA detected by 16 s

rRNA assay was established. However, such correlation is used

only as an indicator of the approximate amount of CFU pres-

ent in the sample but not to conclude the actual amount of

CFU. Such recommendation is based on the observation that

relationship between CFU and 16 s rRNA varies among differ-

ent growth phase and when under different stress conditions.

Acknowledgments

The research leading to this chapter was supported by the

Innovative Medicines Initiative Joint Undertaking under grant

agreement no 115337, resources of which are composed of finan-

cial contribution from the European Union’s Seventh Framework

Programme (FP7/2007-2013) and EFPIA companies’ in-kind

contribution.

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Using RT qPCR for Quantifying Mycobacteria marinum from In Vitro and In Vivo Samples