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To fully appreciate the extent of my misfortune and its final relief I have to take this review back to last Tuesday.

I was going to purify a protein, which was to be used for antibody production. So Tuesday evening I set my BL21s to grow overnight.

Wednesday morning the culture was diluted to 500 ml and I let it grow dense. This took some hours. Then, the production of the protein of interest was induced by IPTG and the bacteria were left to grow and express the protein for another four hours. The next step: harvesting. I think this has a nice ring to it. Sounds agriculturish and like old-fashioned working, when it is just a question of getting the bacteria free from medium. This is preferably done by centrifugation. So I transferred the 500 ml to a Beckman centrifuge bottle and filled another one with water to act as the counterweight. Set the centrifuge to 10000 rpm for 30 min. 10000 rpm is the maximum of what the rotor can withstand.
Sitting in my room, playing Tetris Plus and waiting for the time to pass I suddenly hear some upset yelling in the corridor. Then I get unpleasantly aware of the floor trembling beneath my feet and the load roar, like an upset elephant mother barking to get the vultures away from her cub, emerging from...Oh, no!...from the centrifuge room! Somebody starts hollering my name and I dash to withhold the ancient centrifuge vibrating to the extent where it nearly takes off from the floor and threatens to start jumping around the room and inflict great bodily harm to everybody present.
It is fascinating to see how people gather around at these kinds of events, and how a great part of them seems amused. Smiling at me as the little diode under the text "imbalanced" flickers hysterically.
The centrifuge slows down, still shaking vigorously and people start leaving the room, not to feel obligated to take part in the cleaning I presume. The source of the imbalance shows to be one of the bottles exploding. I get informed by one of the bystanders (the only one who actually seems a bit worried and concerned with my misfortune) that the 500 ml Beckman bottles cannot cope with more than 6000 rpm, and tends to burst at higher speeds.
However, my luck isn't all bad as it shows that only the container holding water that exploded. The one holding my bacteria is still intact so I stuff it in the freezer for lysis of the BL21s. I get to leave the lab and go home after spending about half an hour cleaning up the freezing cold centrifuge and cursing at the rags and paper towels getting stuck, as the water they're soaked it freezes into ice and makes them cling to the centrifuge in much the same manor as dry porridge sticking to a plate.

On Thursday I go to the tedious task of purifying the protein from the bacteria: resuspending, leaving on ice for 30 min, sonicating, centrifuging, resuspending, sonicating, centrifuging, dissolving in urea. And then, when everything is just about finished for the day and all I have to do is to screw the cap back on to the tube - in some unbelievable clumsy manor, which as I recall it violated at least two laws of nature, I manage to pour all of my sample into the box of ice standing on my bench. FUCK IT!
Well, no other option seems to exist than starting all over again. So, on Thursday evening I set up two overnight cultures of BL21s, just to be sure, and grind my teeth all the way home.

On Friday morning I manage to oversleep and arrive at the lab sometime around noon. I dilute the cultures and let them grow til about 0300 pm, and then the IPTG induction goes on until 0700 pm. At this time there's no one but me left at the lab. I have to run my bacteria at rather high rpm to assure that most of them get harvested. Since it was brought to my knowledge that Beckman make bottles for their 10000 rpm rotor that only can withstand 6000 rpm (great move, Beckman!) I go on a quest for some other containers. Finally I find two 500 ml Nalgene bottles which fit the rotor.
But, how can I be sure that these won't rupture as well? Not a soul to ask at the lab, and being logged in at Everything2 I see no other option than to run my question through the chatterbox.


Ereneta: I thought Nalgene was indestructible. Go for it.

N-Wing: Just spin as fast as possible. Once it explodes (if it does), you'll know for the future.


Hmmmm...The response I get doesn't make me feel quite certain about the amount of stress a Nalgene bottle can stand, but at least I feel encouraged to spin the bottles at 10000 rpm just to see weather the strain will be too much for them

I can happily report that 10000 was no big deal for Nalgene, and my sample is safe and sound within the caring shelter of the 500 ml containers.

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