Hi everyone,
I was wondering if someone could possibly help me
I’m in my first year of uni and one of my courses Is for microbiology
I’ve been given bacteria that I need to identify through various tests
I’m stuck between two bacterium for two specimens;
Here are the tests I have done for both specamins done on TSA:
1. It is a creamy white morphology that looks almost fluffy on TSA agar.
Gram: positive
Catalase: positive
Oxidase: negative
Indole test: orange
Under the microscope there are small purple rods gathered in almost what look like clusters in big groups all tightly packed together
2. A white creamy morphology too however they are round singular colonies in shape and have “rings” within each single colony
Gram: positive
Catalase: positive
Oxidase: negative
Indole test: yellowy
Under the microscope they are rods arranged in singular long chains
I feel like the first one is bacillus subtillis and the second one is bacillus megaterium
As they are both positive in the starch test and all the information I can find online says they both hydrolyse protein on milk agar- I have no idea what tests to do In order to be certain which is which?
If anyone could please offer me some help I’ve been losing my mind for a week 😕 🙁