Yahoo Answers is shutting down on 4 May 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Bacteria identification?
Can someone name a bacteria that has these following characteristics:
1) Smooth border/texture on colonies
2) Colony size around 4mm, but can be a bit greater or less
3) Gram negative
4) Coccus/Spherical
5) Colonies are yellow on outside but red/brown on inside
6) Smells kind of like original flavored potato chips but more potent [I'm not sure about this one, since it might have been the agar smell mixed with the bacteria smell. Disregard this fact if needed...]
At first I thought it might have been Staphylococcus aureus or S. epidermidis since we've used that a lot in most of our labs, but after I thought about it, none of them have red centers and are gram negative. I also considered it maybe being Serratia marcescens since we also used that before, but that's bacillus.
Just curious, because my teacher used this type of bacteria in one of my labs, but he never told us what is was and said he wouldn't tell us until much later. ): Just basically any bacteria that fits that description and is commonly used in classrooms and research.
@MarMelade: Sorry I forgot to put in details on the agar!
We used LB agar. I'm pretty sure my information was accurate because the rest of my grade gram stained and grew the same type of bacteria and we all got the same results.
Also, it's not really a normal school setting. I go to a high school that specializes in stuff like this, so we have an extremely wide variety of microbes as well as tools at our disposal [significantly more than our surrounding universities and colleges]. That might widen the scope a bit...
I'm pretty sure it's non pathogenic because pathogenic bacteria aren't allowed in our school unless the user has special permission. If the teacher is using a pathogenic bacteria, they're required to tell us that before hand. [and my teacher didn't say anything about that]
I'm starting to doubt whether LB agar was used. Typically we use and make our own agar, so we know what type we're using. But this time our teacher made it for us and he didn't tell us what type he used. [I guessed based on smell, color, and the fact that we most frequently use LB agar.] It could have been other types of agar, since our school uses many different types of agar on a regular ba
3 Answers
- SLLv 49 years agoFavourite answer
First of all, it is impossible for it to S. aureus or S. epidermidis because they are both Gram POSITIVE. You said that the bacteria is Gram Negative.
Secondly, you said that the bacteria is cocci in shape. Adding this 2 together, very little bacteria is actually gram negative cocci. Since this is a school experiment, I would think that the bacteria are non-pathogenic, which could be some type of Neisseria sp.
But you said that the agar is LB agar, and Neisseria sp. bacteria are fastidious, which would not grow on LB agar. So, I am not sure if you got the shape of the bacteria wrong or the agar.
EDIT: We cannot really tell you more unless you find out what type of agar you are using. Plus, did you incubate it in aerobic or anaerobic condition?
Source(s): MLT (ASCP). Done lots of culturing. - 9 years ago
The colour of a colony can also depend on the type of medium on which it's grown; thus, it's difficult to say for certain what organism you have without knowing the medium. However, there really aren't that many gram-negative cocci that would be used in a teaching lab, as many are pathogens. Thus, I would double-check either the gram-stain results or the cell shape to make sure that your observations are accurate.
Source(s): PhD in microbiology - gracielaLv 49 years ago
Last year I took Microbio and I was sure I had S. Aureus but it turned out to be Micrococcus Luteus. My professor said he wouldn't hand out S. Aureus in a classroom. But mine was gram positive. My book didn't have a lot of info about gram negative cocci.
