Question

What is is the difference between streptococci and staphylococci?

Answer 1

The term Cocci has come from coccos meaning spherical in shape,so bacterium which resembles the shape of a sphere,is termed as Cocci,

Cocci are classified as follows,

Below showing some very basic differences between staphylococci and streptococci,

Now, staphylococci is arranged in grape like clusters because their cell division occurs in three planes but for streptococci it occurs in two planes only,so they are arranged in chain.

One,more important feature of staphylococci is that they show charecteristics oil paint appearance on nutrient agar.

Now,it is very important for a medical microbiologist to identify the difference between these two,as the doctor will rely on its report for the selection of drug against the bacteria.

Streptococci are classified on the basis of hemolysis and based on C carbohydrate antigen known as Lancefield Classification. ( This classification is very big,so not discussing here)

Some diseases caused by Staphylococci are:

1 . Pyogenic abscess formation

2 . Pyogenic osteomyelitis

3 . Nosocomial pneumonia

4 . Paronychia

5 . Bullous impetigo

6 . Pemphigus neonatorum

7 . Food poisoning( milk products mainly)

Some diseases caused by streptococci are:

1 . Scarlet fever

2 . Sore throat

3 . Cellulitis

4 . Erysipelas

As streptococcal antigens resemble our body tissue's own antigen(molecular mimicry),complications are seen due to destruction of own body tissue by the antibodies produced against them,causing

ACUTE RHEUMATIC FEVER

POST STREPTOCOCCAL GLOMERULONEPHRITIS