What bacteria could this be?

[jessaimeewhite]

I'm currently a student studying BSc Biology and for part of my food microbiology assessment, we have had to grow bacteria from cheese types in cultures (of different dilutions).

So I have managed to identify all them apart from this one, I was wondering if anyone could point me in the right direction.

The bacteria in question is:
Circular,
Raised,
Entire,
Dark yellow,
Negative for the catalase test and
Negative for the oxidase test.

The only possible bacterium I can think of is Bacillus subtilis.

Any other ideas?
Thank you.