Weird results with bacterial transformation - (May/16/2015 )

Thank you for good idea. I can applied to use in next time.

<พนันบอลออนไลน์ : po

You’ve already done most of the tests I would suggest. Can you dilute enough to get single contaminant colonies (not a lawn) and can you ID the little suckers (like at least a gram stain and colony morphology)? Does the morphology resemble the Lactobacillus? Maybe there is a microbiology lab that can help.  All you need to know is if they are truly not E.coli, as I suspect they are not. Whatever it is seems to be Amp resistant. Are they resistant to anything else you might have in the lab, like Tetracycline? Then the question is where are they coming from?

Could it be some buffer you are using to dilute your plasmids but not your water negative control?

Have you tried a different plasmid with the same comp cells? I mean one with a different selective marker?

Have you recently opened a new bottle of agar stock? If you incubate the agar alone (no antibiotics) is it sterile? Liquid LB as well?

You have my sympathies!