are bacteria belonging to the family and gender main streptococcaceae streptococcus, a very large genus that includes many species that are similar to each other for many metabolic characteristics and morphological but are very different for the habitat and the relationship with man.
streptococci are bacteria responsible for various diseases such as pneumonia, bronchitis, scalattina, caries, septicemia, urinary tract infections ecc.ecc.ecc.
All streptococci are gram + cocci arranged in chains or oval, asporigeni, and have no flagella. Are oxidase and catalase -, tolerate low oxygen. ferment the sugar and agar colony forming small.
CLASSIFICATION
1 Rating: based hemolytic activity of the bacterium, namely the ability to damage red blood cells. Alfa Haemolytic
: when bacteria break down red blood cells but not transformed into a compound of hemoglobin color green.
Beta Haemolytic: When bacteria break both the red blood cell hemoglobin
Haemolytic Range: When not change any of them.
* Streptococcus is more dangerous because the beta-hemolytic streptococcus Piogenes .*
2 ° The classification Lancefield, is based on the recognition of a particular antigen polysaccharide antigen C said this on the wall of strepto.La presence of this antigen indicates the danger. The most pathogenic streptococci are grouped into group A streptococci, the second most dangerous in group B streptococci and so on.
3 ° The classification of Sherman, combines all the data on the ratings mentioned above.
VIRIDANTI: Alpha hemolytic, often without antigen, diners in the mouth .. The viridanti Mutans streptococci are pathogens responsible for tooth decay.
pyogenic: Beta hemolytic, Group A streptococci, All-pathogenic S. pyogenes.
faecal Alpha, Beta, Gamma Emolitic, Group D streptococci, intestinal opportunistic pathogens
MILK: gamma hemolytic, Lancefield group N, often used in the food
PNEUMONIAE *: Causes pneumonia, Alpha hemolytic.
Practical Experiences
ACTIVITIES 'HAEMOLYTIC:
It grows on a soil bacterium called AZIDE blood agar, nutrient agar with added sheep blood, you incubated
x 24 hours 37 ° C, observes,
* X I've Sown The bacterium is a pathogenic bacterium because all'intor 
no colonies there is a double halo, which indicates that the bacteria have damaged red blood cells.
IDENTIFICATION OF THE BACTERIUM CONSIDER
after discovering that they are beta hemolytic, we sowed the same bacterium in another land to Striplosemplice Azide Blood Agar, we somesso of paper discs containing antibiotics that are known and optochin bacitrocina.
As you can see the bacteria is not sensitive to bacitrocina (above the disc) but is sensitive to 'optochin (under the disc) so we can see that the bacterium is a Fecalys.
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