So we just finished Gram and acid-fast; tomorrow I'm doing capsules and endospores. We had trouble with the acid-fast because our Mycobacteria were too old; we had to reinoculate a new test tube to get 24 hour-old bacteria. Apparently the waxy lipids in the cell wall get stiff, and won't admit carbolfuschin (I think? Sally?).
As far as differential media go: today we observed our OF-Glucose deeps and the starch agar (way groovy yellow glow from the Bacillus subtilis!) and made SHITloads of media. Off the top of my head, we made Phenyalanine agar slants, Peptone Iron broth, urea slants, Triple Sugar Iron agar deeps, TSA slants and TSB, MRVP broth, and another that I'm forgetting. We still have to make a bunch of plates. Sigh. Sally, do you guys make all your own media, too? It seems like 90% of this class is spent making media.
We also inoculated lactose, sucrose and glucose broths to watch for fermentation, with the adorable little Durham tubes.
"Go away! Last words are for fools who haven't said enough!" - Karl Marx, last words
No, we haven't made any. We poured one plate to practice aseptic technique, if it grew something, we did it wrong. Mine did not grow a thing! We have been using pre-made for everything. And yeah, you gotta use the fresh broth to be able to see anything. Of course, the slides we used for the acid-fast were pre-made for us, the only time this has happened.
My lab coat is fast becoming an interesting collection of pink, purple, green, and blue spatters. I think I'm going to give up and call it "polka-dot." It's a good thing we take them home to bleach every quarter!
My professor was talking about how they use bacteria to test the harmful effects of certain chemicals before testing on animals then finally humans since it's cheaper than bunnies and there's also no People for the Ethical Treatment of Bacteria... yet. He actually made a joke. lol
This user laughed so hard that they peed a little:
I'm going crazy, I really am. Tonight I have to start and finish my write up for the Structural Stains lab, start writing the Glucose/lactose/sucrose Fermentation lab, and start my Tissue Culture journal. This is an insane amount of writing.
To make matters worse, my teacher is a complete and utter bitch. She wrote us an e-mail re: feeding our lymphocytes in Tissue Culture, and I quote:
Your media should have:
10% FBS and
5% pen strep.
The math will matter, but not as much as you would think. Even though 10% of 500 is 50, you will want to take into consideration that by adding 50 mL you are no longer at 500mL total, but at 550mL. So add 1-3 mL more of FBS. It does not have to be EXACTLY 10%, but a MINIMUM (without wasting the FBS).
The pen strep is given in “units”. I should have you do the requisite research to learn what those “units” are and how they relate to mL’s, but frankly, I don’t have the energy and you don’t have the time, for the frustration that always ensues. Suffice to say, it's about 3mL of the frozen pen strep stock (which is at 10x) we have in the freezer will give you a 3% concentration. If you are unhappy being given this knowledge, without looking it up yourself, please feel free to do some research to confirm.
First off, lady, I resent the snarky "energy/time" comment when we're in the fucking lab from 7:45 am till 3:30 pm and don't even take a lunch break. YOU'RE the one who wouldn't let us even START Tissue Culture until after the 5th week.
Secondly, how hard is it to tell us that a "unit" of these two combined drugs is right around 0.3ml if you just gave us the 3% value of a 10x concentration? But, oh wait, WHOOPS!!! The concentration that is ACTUALLY in the freezer is 100x, or ten times as strong! Gee, lady, I wonder what would have happened if we'd dosed our poor lymphocytes with 3ml of 100x pen/strep. So maybe we should actually give our cells 300 microliters, not 3 milliliters, hmmm? Math much? Stupid bitch.
Seriously, my lab partner and I are doing this entire thing ourselves, without her help. I bet she got fired from her last job and took this teaching job as an easy way out.
Good grief. We have lecture from 10:05 am to 11:20 then lab from 12:45 to 2:45 Tues and Thurs.
I actually like this instructor even if he rarely smiles. Today we checked out our cultures and then did another thing from our lab book. The starch agar had to have an extra step of adding Lugol's iodine to see where the bacteria "ate" the stuff in the medium (can you tell I'm feeling a bit brain dead tonight!). We had to work in groups of four for this and the guy in our group didn't even think when he picked up the plate that was flooded with iodine and flipped it over... iodine all over the floor! We made him watch the next part. We started with two different red dyes and had two tubes with 5 mL of water each, added 5 drops of one dye to one tube and the other dye to the other tube. Then we added 5 drops of hydrochloric acid to both tubes and watched them change color, then added 5 drops of sodium hydroxide, no color change, added a drop, mixed, looked for color change...kept adding drops til the color changed, ended up with one bright pink tube and one bright yellow tube (like urine if you've been taking vitamin B).
Thank God that our lab TA, Richard, is there. We ask him all the questions that we have - we're essentially ignoring Sheryl, our teacher, at this point. Richard is the bomb. He's a) hilarious, b) thorough, and c) helpful. Sheryl is none of the above.
Today in Tissue Culture, we made up our lymphocytes' (cancer cells that some guy donated) media (food), centrifuged the cells down into a pellet, then poured off the supernatant and poured the cells into their yummy new home.
In Micro we didn't do much; we observed the 48 hour reaction of our glucose/sucrose/lactose fermentation, then reinoculated our bacteria bank into new broths, and a couple of bugs into the MRVP test tubes for incubation over the weekend.
A couple of students who are in their 6th quarter (Becca and I are in our 4th) and doing external internships (like at the nearby Army hospital/research lab, and a VA hospital/lab up in Seattle) stopped by today. They told us that we're in the hardest quarter right now, so phew! Downhill from here, baby. At least after this quarter, LOL.
So Wednesday is the last day of the quarter, then a month off, yay! I'm going to need it!
I'm finishing up my second to last test (the class is self-paced, independent study) and suddenly come upon a question on restriction mapping. WTF? We never covered this anywhere during the quarter, and now I have to learn how to make a restriction map? It doesn't seem that hard, but the question is worded very poorly and the informational pictures aren't helping.
God I can't wait to graduate away from this bitch.
We were assigned a mixed culture of 2 unknown bacteria at the beginning of the quarter; we were also given a bank of 21 different species that we had to maintain and run tests on over the quarter. Alongside the bank, we ran tests on our unknowns. Today I finished writing up the official lab report on the identification of my unknowns. I'm so brain dead. Been doing nothing but micro for 16 hours today. Yay for Enterococcus faecalis and Proteus mirabilis!