Table of Contents
What are the ways to identify bacteria?
Bacteria are identified routinely by morphological and biochemical tests, supplemented as needed by specialized tests such as serotyping and antibiotic inhibition patterns. Newer molecular techniques permit species to be identified by their genetic sequences, sometimes directly from the clinical specimen.
What tests are used to identify bacteria?
Tests used to identify Gram Positive Bacteria
- Catalase Test.
- Mannitol Salt Agar (MSA)
- Blood Agar Plates (BAP) Streak-stab technique.
- Taxos P (optochin sensitivity testing)
- Taxos A (bacitracin sensitivity testing)
- CAMP Test.
- Bile Esculin Agar.
- Nitrate Broth.
What 4 characteristics are used to identify bacteria?
Features that distinguish a bacterial cell from a eukaryotic cell include the circular DNA of the nucleoid, the lack of membrane-bound organelles, the cell wall of peptidoglycan, and flagella.
Why do we identify bacteria?
Microbiologists must identify bacterial isolates for several practical reasons: • Medical diagnostics — identifying a pathogen isolated from a patient. Food industry — identifying a microbial contaminant responsible for food spoilage. Research setting — identifying a new isolate which carries out an impor tant process.
How do you identify bacteria on a petri dish?
Colony morphology is a method that scientists use to describe the characteristics of an individual colony of bacteria growing on agar in a Petri dish. It can be used to help to identify them. A swab from a bin spread directly onto nutrient agar. Colonies differ in their shape, size, colour and texture.
How do you identify a bacterial colony?
Each distinct colony represents an individual bacterial cell or group that has divided repeatedly. Being kept in one place, the resulting cells have accumulated to form a visible patch. Most bacterial colonies appear white or a creamy yellow in colour, and are fairly circular in shape.
What method is used to distinguish the two types of bacteria?
Gram staining splits the bacteria into two groups which are gram negative and gram positive. Another method used to identify bacteria is phase contrast microscopy. This method is sometimes used because individual bacteria are very hard to see, in fact they appear to be transparent.
What characteristics are used to identify bacteria?
Bacteria shape: The shape of bacteria is very characteristic to them. It is also easy for the identification of bacteria by recognition of shapes. These bacterial structures have a specific shape like a stick (bacilli), spherical (cocci), coma (cholera bact.), spiral (spirochete), in a bunch or isolated, etc.
How do you identify unknown organisms?
Begin the process of identifying unknown bacteria by observing their physical characteristics, such as cell wall, shape and linkages. Use standard laboratory procedures, like cell staining, culturing and DNA sequencing to further narrow down your identification.
Why are biochemical tests used to identify bacteria?
Biochemical tests are the tests used for the identification of bacteria species based on the differences in the biochemical activities of different bacteria. ADVERTISEMENTS: Bacterial physiology differs from one species to the other. These differences in carbohydrate metabolism, protein metabolism, fat metabolism, production of certain enzymes, ability to utilize a particular compound etc. help them to be identified by the biochemical tests.