The Appearance of Bacterial Colonies: An Important Tool for Microbiologists
Describing the appearance of bacterial colonies has been an important tool for microbiologists. On solid media, a colony is theoretically derived from a single cell. If well separated from other colonies, a colony will have a characteristic shape (both in elevation and margin), size, color, and consistency. Usually, observation is made with the naked eye, but dissecting microscopes are also used. The characteristics defined by a colony’s morphology may be used at a superficial level to distinguish between types of microorganisms. Another comparison can be made when describing pigmented colonies.
In this experiment, E.coli form a circular colony with convex elevation, entire margin and mucoid texture. While Salmonella sp and Shigella sp both form filamentous colony and filamentous margin with dry texture. The elevation for Salmonella sp and Shigella sp colony are flat and raised respectively. Besides that, Pseudomonas aeruginosa form irregular colony, reaised elevation, lobate margin, and wet texture. Other bacteria, that are Serratia marcescens, Proteus vulgaris, and Klebsiella aerogenes form circular colony. For S. marcescens and K. aerogenes they have entire margin while P. vulgaris form even margin. S. marcescens form umbonate elevatiob and mucoid texture. While P. vulgaris form raised elevation and smooth texture. Klebsiella so form raised elevation and dry texture.
For triple sugar ion is used to differentiate enterics based on the ability to reduce sulfur and ferment carbohydrates. It contains lactose, sucrose, a small amount of glucose (dextrose), ferrorus sulfate and the pH indicator phenol red. As with the phenol red fermentation broths, if an organism can ferment any of the three sugars present in the medium, the medium will turn yellow. If an organism can only ferment dextrose, the small amount of dextrose in the medium is used by the organism within the first ten hours of incubation. After that time, the reaction that produced acid reverts in
In this experiment, E.coli form a circular colony with convex elevation, entire margin and mucoid texture. While Salmonella sp and Shigella sp both form filamentous colony and filamentous margin with dry texture. The elevation for Salmonella sp and Shigella sp colony are flat and raised respectively. Besides that, Pseudomonas aeruginosa form irregular colony, reaised elevation, lobate margin, and wet texture. Other bacteria, that are Serratia marcescens, Proteus vulgaris, and Klebsiella aerogenes form circular colony. For S. marcescens and K. aerogenes they have entire margin while P. vulgaris form even margin. S. marcescens form umbonate elevatiob and mucoid texture. While P. vulgaris form raised elevation and smooth texture. Klebsiella so form raised elevation and dry texture.
For triple sugar ion is used to differentiate enterics based on the ability to reduce sulfur and ferment carbohydrates. It contains lactose, sucrose, a small amount of glucose (dextrose), ferrorus sulfate and the pH indicator phenol red. As with the phenol red fermentation broths, if an organism can ferment any of the three sugars present in the medium, the medium will turn yellow. If an organism can only ferment dextrose, the small amount of dextrose in the medium is used by the organism within the first ten hours of incubation. After that time, the reaction that produced acid reverts in