Sunday, October 05, 2008

Something good will come of this ....

Last week, I was combing through some DNA sequences that had just returned from the core facility, assuming that the data would to confirm the success of an experiment that I've been working on for several months. What I found out was that -- well, the data sort of confirmed success. That is to say, some of the problems I'd been having with the procedure had been solved. The only thing was, I also found out from the sequences that I'd made a mistake a few months back that was not only annoying, but truly embarrassing. We are talking about a rookie mistake here, one that an undergrad working on a senior honors project should have been able to catch, and sure enough, I did it myself, and didn't catch it for several months. And I didn't make the mistake in haste -- I made it after great deliberation. Color me very, very severely pissed off.

Okay, in the big scheme of things, it's not that bad. It will cost one to two weeks of work, plus about $100 worth of lab reagents, to fix my screw-up. On the scale of time and money already invested in this project, this is small potatoes. And at least I caught it before compounding the error by introducing it into the next few steps of the experiment. But I do have to fix this as soon as possible, so I decided to haul my butt into the lab for as many hours over the weekend as it took me to make maximum progress. This worked out to about seven hours on Saturday and a couple of brief pop-ins today. But it was the Saturday effort that really paid off in an unexpected way.

Important piece of additional information: There are a lot of people who work in my lab, and on weekends, people are constantly in and out, feeding and breeding flies, running bench experiments, or catching up on their reading and writing. It's probably not unusual for each member of the lab to be in at least once over the weekend without actually seeing any of the others. My first Saturday spell in the lab started at around 10:45 AM and ran for about two hours, during which I retrieved some DNA from overnight cultures of bacteria and began the process of digesting it with enzymes. I then went home for lunch, goofed off with Rick for a few hours while the enzyme digestions incubated, and then returned to the lab for more bench work at around 3:15 PM.

When I walked into the lab, the first thing I heard was an alarm. We occasionally get weird alarms from the fume hood (which only rarely has to handle actual fumes,) and they never amount to much -- I think they're caused by drunken Drosophila from some ongoing ethanol-exposure experiments weaving in and out of the chamber. At least, that's what I first assumed was going on. But when I got to the hood, I realized the alarm was coming not from it, but from the -80ºC freezer in the next room. This is a very, very bad thing. Alarms coming from our "minus 80" mean that the temperature is higher than minus 80 -- in fact, it means that the temperature is -65ºC or above. Now, most of us humans cannot wrap our minds around the difference between minus 80 and minus 65; exposure to either temperature is remarkably effective at, for example, causing your skin to stick painfully to the shelf if you're distracted enough to reach into the freezer with wet ungloved hands. But some of the things that we keep in the minus 80 can most definitely tell the difference between minus 80 and minus 65. Like, for instance, the chemically treated E. coli that I have to use in some of my genetic experiments. These are not run-of-the-mill, sewer-dwelling E. coli. These are highly upscale, $200-per-box-of-25-tiny-tubes E. coli, and they become extremely petulant and refuse (permanently) to cooperate in experiments if kept at minus 65 instead of minus 80 for a prolonged period of time. And they really, really don't like minus 47, which is what the temperature display was reading by the time I got there. And it was reading minus 47 because someone who had been in between 12:45 and 3:15 PM had forgotten to fully latch the door after retrieving material from the freezer. (Wasn't me. I hadn't opened the freezer during my first trip to the lab. One rookie error per person per year is more than enough.)

Oh, and freezer alarms are supposed to go off in the facilities manager's office, as well as in a central facility in another part of campus. This one didn't. Our facilities manager, I think, lives in her office, and she is the kind of hyper-vigilant person who can probably hear a drunken Drosophila staggering into a fume hood from two floors down. Despite the fact that it was Saturday, she was there when I called to leave a message, and she'd heard nothing. The central facility, in fact, phoned me twenty minutes later to tell me that our freezer alarm was going off, by which time I'd closed the door, watched the temperature creep back below minus 60, and repeatedly re-set the alarm because if you hit the reset buttton to turn off the noise, the alarm only pauses for about five minutes. After that, if the temperature is still too high, it starts howling at you again. But it took, most likely, several hours for this whole mess to set off the remote alarms.

In other words, our freezer had failed to communicate with its minders.

And the next person to enter the lab didn't do so until around 7 PM. I know, because I was there until 8:30.

All because I messed up an experiment a few months back and had to come in on a Saturday to fix it.

And caught the open-freezer problem in some period of time that was less than or equal to two and a half hours, as opposed to six and a quarter hours.

Damned good thing I screwed up that procedure a while back, no? :-)