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Reusing LB/amp/xgal plates (also, how long can e. coli be in the incubator for?) - (Jul/11/2009 )

Hi guys! I'm completely green at this, and I messed up my transformation by adding the growth media too early, which I think might've ended up starving and killing the competent cells. As a result, 4 of my plates didn't have anything on them. They were plated on LB/amp/xgal, and each of them was plated with either 30 or 60 uL of transformant. They've been in the incubator for about 24 hours. Is it okay to reuse the plates? What if I added more amp and xgal?
Also, if I re-transformed and plated the bacteria today (at the latest, 7 PM), could I leave the plates in the incubator until Monday morning? I don't want to starve my cells again LOL.
I'm only a lowly summer intern who doesn't have access to the autoclave on weekends, so I'd have to wait until Monday to make new agar, and if I incubated on Monday, I'd have to wait until Tuesday to pick colonies and submit stuff for sequencing. And I want to get as much stuff done was possible, because I only have a couple more weeks (ah!!), so I need to submit ASAP.
Thanks for any help!

-Soda-

I wouldn't reuse the plates.
I know you are stressed about losing a day or two but it is better to do things properly from the start rather than going ahead anyway and then finding a problem further down the track and having to start again, losing even more time.

Good luck with your project

-leelee-

I second leelee. I would definitely use a new plate too.

-jiajia1987-

Thanks for the replies! And the luck :)
Could've definitely used it today - ugh, what a horrible Monday.
I forgot that I poured a couple extra plates to begin with, and I just used those, the problem never even existed! Haha good advice though, I'll remember it.

-Soda-

Good to hear, I was going to suggest pouring extra plates next time (I usually do that too) but wasn't sure if you'd be happy to hear that kind of thing when you are in stress-mode!! :)

-leelee-