Microbiological identification methods

I.
Microbiology
Identification Methods - Traditional Methods
In the traditional classification identification, the main basis of microbial classification identification is morphological characteristics, physiological and bio-reaction characteristics, ecological characteristics, as well as
serynological
response, sensitivity to phages and so on. In the identification, we use these as identification projects, a series of observation and identification work.
1, morphological features
(1) cell morphology
under the

microscope to observe cell size, shape, arrangement, cell structure, Gram staining reaction, whether movement, whiplash living site and number, whether there are spores and membranes, spore size and location, line bacteria and fungi reproductive organs shape, structure, shape, size, color and surface characteristics.
(2) Group morphology
group form usually refers to the characteristics of the following:
the appearance, size, gloss
, viscosity, transparency, edge, bulge, positive and negative color, texture, odor, secretion of water-soluble color The characteristics of moss grown on a certain sloped medium, including growth degree, shape, edge, bulge, color, etc., the growth after puncture on a semi-solid medium, the growth in liquid medium, including whether to produce a bacterial membrane, uniform turbidity or precipitation, whether there are air bubbles, the color of the medium, etc. If it is yeast, also pay attention to , ring or island-like.
2, Physiological, bio-chemical reaction characteristics
(1) Ability to utilize substances
including the ability to utilize various carbon sources (co2 as the sole carbon source, the use of various sugars, etc.), the ability to utilize various nitrogen sources (whether nitrogen fixation, nitrate and ammonium salt utilization, etc.), energy requirements (light energy or chemical energy, oxide inorganic or organic oxide, etc.),
growth factors
requirements (whether growth factors are required and what growth factors are required, etc.).
(2) the particularity of metabolites
there are many identification items in this regard, such as whether to produce H2S, radon, CO2, alcohol, organic acid, whether to reduce nitrates, milk solidification, freezing and so on.
(3) relationship between temperature and oxygen
the temperature range suitable for the growth of a microorganism and its most suitable growth temperature, minimum growth temperature and maximum growth temperature. For the relationship between oxygen, see if it is aerobic, trace aerobic, both aerobic, oxygen-resistant or specialized anaerobic.
3, ecological characteristics
ecological characteristics mainly include its relationship with other organisms (whether parasitic or symbic, host range and disease-related conditions). Distribution in nature (pH, moisture level, etc.), osmosis pressure (resistance to high seepage, salinity, etc.).
4, Serological response
Many bacteria have very similar physical structures (such as whiplash) or enzymes that act the same (e.g., lactobacillus lactobacillus bacteria have lactic acid dehydrogenase). Although their
proteins
different molecular structures, they cannot be distinguished under common techniques, such as electron microscopes or bio-chemical reactions. However,
highly sensitive specific reactions to

antigens
and
antibodies can be used to identify similar strains, or to the same microbial type.
an anti-serum made from a known strain, type, or strain, and whether a specific serological reaction occurs with the object to be identified to identify an unknown strain, type, or strain.
is commonly used for the classification of enterobacteria, phages and viruses. Using this method, typhoid bacteria, streptococcus pneumoniae and other bacteria have been divided into dozens of types of bacteria.