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Furthermore, the term culture is more generally used informally to refer to "selectively growing" a specific kind of microorganism in the lab. It is often essential to isolate a pure culture of microorganisms. A pure (or axenic) culture is a population of cells or multicellular organisms growing in the absence of other species or types.
The microorganism must be found in abundance in all organisms suffering from the disease but should not be found in healthy organisms. The microorganism must be isolated from a diseased organism and grown in pure culture. The cultured microorganism should cause disease when introduced into a healthy organism.
Influenced by Henle and by Cohn, Koch developed a pure culture of the bacteria described by Davaine, traced its spore stage, inoculated it into animals, and showed it caused anthrax. Pasteur called this a "remarkable achievement". [7] In pure culture, bacteria tend to keep constant traits, and Koch reported having already observed constancy.
Epidemiology, the study of the patterns, causes, and effects of health and disease conditions in populations, is an important part of medical microbiology, although the clinical aspect of the field primarily focuses on the presence and growth of microbial infections in individuals, their effects on the human body, and the methods of treating ...
In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera, diphtheria, and anthrax. Because microorganisms include most unicellular organisms from all three domains of life, they can be extremely diverse. Two of the three domains, Archaea and Bacteria, only contain microorganisms.
Corynebacterium glutamicum is one of the most important bacterial species with an annual production of more than two million tons of amino acids, mainly L-glutamate and L-lysine. [29] Since some bacteria have the ability to synthesize antibiotics, they are used for medicinal purposes, such as Streptomyces to make aminoglycoside antibiotics. [30]
Thus, the plate can be used either to estimate the concentration of organisms in a liquid culture or a suitable dilution of that culture using a colony counter, or to generate genetically pure cultures from a mixed culture of genetically different organisms. Several methods are available to plate out cells. One technique is known as "streaking".
The growth of bacteria in laboratory cultures is the mainstay method used by bacteriologists. Both solid and liquid culture media are used. Solid culture medium is usually nutrient agar in a petri dish. The constituents of the nutrient agar vary according to the bacteria under investigation.