Microbiology for dummies?

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yaah

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Due to my busy schedule of late I start my micro month tomorrow and I don't know anything. I am trying to remember stuff from med school but all I can remember is that chocolate agar grows something specific, acid fast organisms don't often grow on normal culture media, and what staph aureus looks like.

I also know that when a bug has the letter "T" in it, more often than not it is gram positive. If there are two Ts, it often cancels it out. (see, "t" looks like a "+"). I should patent this method for remembering bug type because everyone is always impressed when I tell it to them.

Gram (+): Staph, Strep (2 Ts but if you remember it as strep you do fine), Enterococcus, Clostridium, Lactobacillus, Listeria, Corynebacterium, propionobacterium, peptostreptococcus (3 Ts).

Gram (-): Neiserria, Haemophilus, Enterobacter (two ts), pseudomonas, citrobacter (two ts), moraxella, Eikinella, Kingella, Legionella, brucella, E coli, Salmonella, Shigella, Yersinia, Aeromonas, Vibrio, Burkholderia, Acinetobacter (two ts).

Doesn't work for: Proteus, bacillus, bordetella (but it does if you call it bordetella pertussis - two Ts), actinobacillus.

Based on that, it's easier to remember the exceptions to the rule, eh? The only time this rule failed me is darned old bacillus (gets me everytime) and the time I was convinced Enterococcus was an exception - then I remembered that enterobacter is gram (-) because it has two Ts. Of course, now I just remember "bacillus anthracis" and since there is a T in there, bacillus can be gram (+) now. So that just leaves proteus.

Now I have to figure out how to remember aerobes vs anaerobes. My rule of "when in doubt, the confusing and long name that I don't hear very often is an anaerobe" just doesn't cut it very much. Of course, if you are a clinician, you can just throw around the term "anaerobes" because apparently they all have the same treatment.

Anyone know of a good website that teaches good microbiology techniques in a few minutes? Like, what pimp questions are they going to ask me tomorrow that I will have no idea? What is an alpha pattern? Beta pattern? What type of media does M. Tb grow in? What is the best test for CMV? Etc.
 
Yaah,

I know that this doesn't answer the real question of the thread. But,
the media used to grow M-TB is called either Middlebrook or Lowenstien- Jensen Agar. Also, the Alpha pattern is basically a greening of the blood agar. Beta pattern is just a clearing of the blood agar. (I'm assuming that you are referring to hemolysis seen on blood plates).

You might try Todar's Online Textook of Microbiology at www.textbookofbacteriology.net
 
Yeah, I know about hemolysis patterns. Actually learned a lot today but had no real responsibilities. I did a couple of gram stains and looked at a lot.

BTW, who knew "Chocolate agar" did not actually contain chocolate? Learn something new every day, I guess.

I wish I could invent a new bacterial plating media. Then my name would be immortalized for the future generations who streak plates.
 
yaah said:
who knew "Chocolate agar" did not actually contain chocolate?
I did! 😀 I asked, during a microbio selective - "So, bacteria like chocolate too?"

It sure didn't smell like chocolate.
I assure you, I was not mad enough to lick it, hungry though I was as always.
 
deschutes said:
I did! 😀 I asked, during a microbio selective - "So, bacteria like chocolate too?"

It sure didn't smell like chocolate.
I assure you, I was not mad enough to lick it, hungry though I was as always.

chocolate agar actually smells like poo
 
I am glad bacteria don't like chocolate.

Sad to say, I never quite got the hang of doing a Gram stain - mine always looked pale. I could never tell if I rinsed it too fast or didn't leave it to dry long enough or left the alcohol on for too long.

You know what I really want to see under a scope? Coccidioidomycosis. What a name!
 
deschutes said:
You know what I really want to see under a scope? Coccidioidomycosis. What a name!

I would prefer to see Sporothrix. Fungi have great names.

mico020.jpg
 
I got your coccidio right heeya!

2330014.jpg


kinda looks like a transverse cut of a spicy tuna roll...well not really.
 
AndyMilonakis said:
I got your coccidio right heeya!
Hmm... Not quite as impressive as the name, huh?

What was really impressive though, was the moment I first heard of this organism.

I was doing two weeks of path at the end of first year, and my prof got me to come take a look at a bit of lung - for some reason I think it was a frozen because we were in the gross room - on a lady who had some respiratory infection, no other history.

Holy crap! Hen's teeth!
What an eye! What a mind!
I didn't even see the tiny scattered purple spots until he pointed them out. And I certainly don't think I could recognize them again on my own at this point.
 
okay, i might be totally alone in this....yes, i'm sure i am....but, i've always thought some micro images beautiful enough to hang as art. 😳
btw, isn't chocolate agar like sheep's blood or something? it's too nice outside and i'm too lazy to look it up.
 
Micro? 🙂 I don't know about microbio, but I do have an unframed Periodic acid-Schiff micrograph print on my wall... contrasts well with the pale green (I didn't do the paintjob, the last tenant did).

Yup, chocolate agar is sheep's blood, disgustingly enough.

I think there's nothing better than letting all the breeze and sunshine in - and falling lazily asleep if I so choose. And I think, I will choose!
 
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