General characteristic.
The overwhelming majority is purulent - inflammatory diseases cause cocci, i.e. microorganisms having the spherical (spherical) form. Them divide on two greater groups - grampositive and gramnegative. Inside of these groups allocate aerobic and facultatively - anaerobic cocci and anaerobic cocci.
Among grampositive aerobic and facultatively - anaerobic cocci the greatest value microorganisms of family Micrococcaceae (sort Staphylococcus) and have families Streptococcaceae (sort Streptococcus), among gramnegative aerobic and facultatively - anaerobic cocci - representatives of family Neisseriaceae (N.gonorrhoeae - honococc and N.meningitidis - meningococcus). Among grampositive anaerobic coccus the greatest value have peptococcus и пептострептококки, among gramnegative anaerobic coccus - veillonell.
Representatives of family Micrococcaceae, capable to cause disease at the person, concern to sorts Staphylococcus, Micrococcus and Stomatococcus.
Sort Staphylococcus.
Into structure of a sort enters more than 20 kinds, from which the greatest value have S.aureus (golden staphylococcus), S.epidermidis, S.saprophyticus.
Morphology. Grampositive coccus for which interposition by congestions in the form of clusters of grapes since they share in mutually perpendicular planes is characteristic. Have a microcapsule, dispute do not form, tails have no.
Cultural properties. Facultative anaerob, hemoorganotrofi. Well grow on simple nutrient mediums, including on environments from 5-10 % NaCl. A temperature optimum from +35 up to +37о With, рН 6-8 (alkalescent reaction of environment is better). On dense environments form opaque round (2-4 mm in diameter) the equal colonies painted in color lipochrom of a pigment (cream, yellow, orange). Except for S-forms of colonies can form R-forms. On liquid environments give uniform turbidity, then the friable deposit drops out.
Biochemical properties. Possess high biochemical activity, form various enzymes, in many respects defining(determining) pathogenicity. Katalaza are positive, oxydaza are negative. Carbohydrates ferment up to an acid without gas, dilute gelatin with formation craters, form hydrogen sulphide. On presence koagulaza them divide on two groups - koagulaza-positive and koagulaza-negative. Among pathogenic kinds koagulaza - it is positive only S.aureus, the others - are negative.
Antigenic structure very difficult (more than 50 types of antigenes). On specificity antigenes subdivide on patrimonial (the general for staphylococcus), crossing reaction (with izoantigen eritrocit, leather and kidneys of the person), type specific.
Species-specific antigenes are teichos acids, fiber And golden staphylococcus. Antigenic properties toxins possess.
Factors of pathogenicity. To them carry a microcapsule, components of a cellular wall (teichos acids, fiber), enzymes and toxins.
1. Factors of adhesion are high waterproof properties of superficial structures.
2. Components of a cellular wall stimulate development of inflammatory reactions, major importance in them have neutrophils.
3. Various enzymes staphylococcus play a role of factors of aggression and protection. A primary factor is plazmokoagulasa, curtailing whey (plasma) of blood and forming tromb substance, staphylococcus and interfering action of protective reactions of an organism. Except for it - fibrolizin, DNA-aza, lecitinaza, fosfotaza.
4. Staphylococcus synthesize an extensive complex ekzotoxin.
Membrane damaging toxins can damage erythrocytes (hemolizin), leukocytes, macrofags, thrombocyte, etc. Allocate some types differing on antigenic structure, a spectrum lizing cells, speed of action.
Exfoliativ toxins render derma necrotic action.
Ekzotoxins, a causing syndrome of a toxic shock. High sorption tampons caused heavy endotoxic a shock in women.
Enterotoxins, with which food intoxications are connected. Enterotoxins - fibers with properties of superantigenes. They cause superfluous synthesis interleykin 2 which causes an intoxication. Intoxications are is more often connected with the use infected staphylococcus dairy products.
5. A number(line) ekzotoxins and other structures staphylococcus possess allergy action, causing effect of development. Presence a cross - reacting antigenes promotes development autiimmunity processes.
6. The factors oppressing fagocitoz - a capsule, fiber and, teichos acids, peptidoglikan, toxins.
Genetics. For staphylococcus the high variability connected with mutations and recombination is characteristic. At them can be various plasmids. Are especially widespread strain with plasmids stability to various antibiotics (first of all - to penicillins). Allocate fagotips and spend fagotipos staphylococcus. For tipes use sets of the moderate phages.
Special properties of the activator.
1. Ability to amaze practically any fabric and body.
2. Very high stability among no spora bacteria to factors of an environment.
3. Constant stay on integuments and mucous membranes informed with an environment.
4. Superantigenic properties.
5. High variability and antibiotic stability, that has great value for epidemic process.
