Characteristic of the exciting growth on culture media such. B. colony size, color and shape provide clues for identification of the pathogen and, combined with the Gram stain, for further testing.

Once a pathogen was isolated culturally, it must be identified. Non-nucleic acid-based identification methods use more phenotypic (functional or morphological) excitation characteristics as genetic characteristics. Characteristic of the exciting growth on culture media such. B. colony size, color and shape provide clues for identification of the pathogen and, combined with the Gram stain, for further testing. Numerous biochemical tests available, each is only for specific pathogen types (z. B. aerobic or anaerobic bacteria) applied. Some test the ability of a pathogen to metabolize various growth substrates. Others examine the presence or activity of key enzymes (eg. As coagulase, catalase). Tests are performed sequentially, previous test results determine the next test being performed. There are innumerable possible test sequences, and they differ somewhat between different laboratories. Non-nucleic acid-based identification methods may include manual methods, automated systems or chromatographic methods. Some kits commercially available include a battery of individual tests that are performed simultaneously with a single inoculum of a microorganism and can be useful for a wider range of pathogens. Multiple test systems can be very accurate, but also may require several days to obtain the results. Chromatographic methods Microbial components or products can be separated and identified by high pressure liquid chromatography (HPLC) or gas chromatography. In most cases the identification is performed by comparing pathogen-specific fatty acids with a database. Chromatographic methods can be used to identify aerobic and anaerobic bacteria, mycobacteria and fungi. The test accuracy depends on the conditions of the pathogen culture and the quality of the database may be inaccurate or incomplete. Mass spectroscopy mass spectrometry can detect different masses in a sample different proteins. Specific pathogens have unique proteins and the relative mass and abundance of each protein can sometimes be used to identify a microorganism. Mass spectrometry is an innovative from a number of technologies that have been developed or to detect biological warfare and bioterrorism agents and identify. However, this method is limited because it can be used, unlike some nucleic acid-based methods, not simply in the field. Currently, a form of mass spectrometry is used, a so-called matrix-assisted laser desorption ionization time of flight (MALDI-TOF) to identify bacteria (including mycobacteria), yeasts, molds and potential viruses. The advantage of this method is that microorganisms in <1 h compared to conventional methods that require 24 to 48 hours, can be identified.

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