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TetA as a counter-selection marker - (Apr/05/2016 )

I am planning of using tetA as a selection (tetracyclin resistance) as well as counter-selection (fusaric acid sensitivity) marker in lactic acid bacteria, mostly lactobacillus acidophilus. Although it is well established that it works for this dual function in E. coli (, I couldn't find any report  on usage of tetA for positive as well as negative selection in lactic acid bacteria (LAB). I can speculate that it should work in LAB as well.

Any comments/suggestions?




Edit: Even Thymidine kinase (TK) (viral?) doesn't appear to have been used for lactic acid bacteria. Can anyone with experience in using TK as a negative selection marker comment on whether it will work in gram positive bacteria like lactic acid bacteria?


I also only use tetA as selection for E.coli.

-Andrea Fortina-