Lab 9/29: Capsule Staining

Today, we determined whether our Unknown Bacteria C has a capsule around it or not. Capsules are highly organized firmly attached polysaccharide accessories to the cell wall which may contain lipids or proteins. If our bacteria is encapsulated, it is able to protect itself from being phagocytized or ingested. Therefore, encapsulated bacteria are able to survive longer in the body than non encapsulated bacteria.

The first picture shows the stains that we used: Nigrosin Stain, and Safranin
The Nigrosin was a black stain that we smeared across the slide with our bacteria on it. Its the stain that brings out the actual capsule. The Safranin stain stained our bacteria.

Encapsulated Bacteria (note: Not our unknown, just an example of what Encapsulated bacteria would look like)

The next picture reveals our bacteria to be non-encapsulated. Our bacteria has a dark inside and light outside where encapsulated bacteria would have a light inside and dark outside (making it look like white holes in a pink background). The picture directly above is encapsulated.