Streptococcus

3 Streptococcus. The streptococci are another important group whose presence is frequently associated with problems. They are commonly found in the throat, a number of dairy products, and also in water supplies contaminated with sewage or faecal material (see later). 

Streptococci may be isolated from materials contaminated with a wide range of bacteria by subculturing onto a medium containing sodium azide which inhibits most Gram-negative bacteria. Sodium azide acts on the cytochrome system and as streptococci have no cytochrome system, they are immune to the effects of this chemical. 

Azide blood agar is widely used for the isolation of streptococci from a number of sources. Azide may become explosive under certain conditions and the manufacturer s instructions should be followed for disposal of media. 

The present classification of the streptococci is based on the presence of various complex carbohydrates known as Lancefields antigens. This allows them to be split into four groups. These are the pyogenic streptococci, the viridans group, the enterococci and the milk or lactic streptococci. Attempts to match these groups with biochemical characteristics run into serious problems. 

The viridans group includes S. thermophilus, which is found in fermented milk 

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Specific bacteriostatic activity against Escherichia coli (681, 896, 899), Staphylococcus aureus (681, 896), Cocci (900), Shigella dysenteriae (681), Salmonella ryphi (681), Proteus vulgaris (681), Pseudomonas aeruginosa (681), Streptococcus (889, 901, 902) and Pneumococcus (901-904). 

Streptococcus Streptococcus 2040 Streptococcus cremoris Streptococcus lactis StreptococcusOK 432... 

Yogurt. Yogurt is a fermented milk product that is rapidly increasing in consumption in the United States. Milk is fermented with Uactobacillus bulgaricus and Streptococcus thermophilous organisms that produce lactic acid. Usually some cream or nonfat dried milk is added to the milk in order to obtain a heavy-bodied product. 

Elfamycins have similar in vitro antimicrobial spectra and the activity against Moraxe//a, Pasteure//a, Yersinia Haemophilus Streptococcus Corynebacterium and Neisseria appears to be common (2,23,72). Aurodox (1, R = CH ) (2), azdimycin (8), LL-E19020a(ll, R = H, R = COCH2CgH ), LL-E19020p (11,... 

Vaccines can be roughly categorized into killed vaccines and Hve vaccines. A killed vaccine can be (/) an inactivated, whole microorganism such as pertussis, (2) an inactivated toxin, called toxoid, such as diphtheria toxoid, or (J) one or more components of the microorganism commonly referred to as subunit vaccines. The examples are capsular polysaccharide of Streptococcus pneumoniae and the surface antigen protein for Hepatitis B vims vaccine. 

L efflux Bacillus., Staphylococcus., Streptococcus Enterococcus, Peptostreptococcus ... 

M ribosomal protection Neisseria, Mycoplasma, Ureaplasma, Haemophilus, Campylobacter, Clostridium, Enterococcus, Staphylococcus, Streptococcus Gardnerella, Kingella, Eikenella, Veillonella, Tusobacterium, Peptostreptococcus Clostridium difficile. Streptococcus pneumoniae... 

Streptococcus pyogenes Streptococcusfaecalis and Staphylococcus aureus show a markedly greater susceptibihty to its action than Escherichia coli and Pseudomonas aeruginosa (205). Thiram has been used ia disiafectant soaps. 

Mice are utilized for testing antiseptics for appHcation to cuts, wounds, and incisions (339). The test bacteria, type 1 pneumococcus and hemolytic streptococcus, ate appHed to the taHs of anaesthetized mice. The tip of the taH is then dipped into the antiseptic for 2 min, after which one-half inch of the taH is removed and inserted into the peritoneal cavity and the incision is closed. If after 10 days the animals survive, the product is considered satisfactory for use as a skin antiseptic. The blood of dead animals is sampled and streaked on blood agar for confirmation of infection from the test bacteria as the cause of death. Since lack of toxicity is another requirement of a product to be appHed to wounds, this test has been combined with a toxicity test (340). 

Susceptible Gram-positive organisms such as Streptococcus pneumoniae and /3-lactamase-negative Staphylococcus aureus. 

Addition of acetic or mineral acid to skimmed milk to reduce the pH value to 4.6, the isoelectric point, will cause the casein to precipitate. As calcium salts have a buffer action on the pH, somewhat more than the theoretical amount of acid must be used. Lactic acid produced in the process of milk souring by fermentation of the lactoses present by the bacterium Streptococcus lactis will lead to a similar precipitation. 

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