Question

Select all of the following that correctly describe the Streptococcus genus

Answer 1

Gram Positive :

Streptococcus is a genus of spheroidal bacteria that belongs to the Streptococcaceae family.

• The bacteria's distinctive clustering in chains that resemble a string of beads is referred to as streptococcus ("twisted berry"). Microbiologically, streptococci are classified as gram-positive and nonmotile.

Cocci :

Streptococcus is a genus of gram-positive coccus (plural cocci) or spherical bacteria belonging to the Streptococcaceae family, which is part of the Lactobacillales (lactic acid bacteria) order in the Firmicutes phylum.

• Gram-positive cocci are a diverse collection of bacteria that have a similar shape. Sarcina cells, for example, are grouped in cubical pockets. Streptococcus spp. resemble a string of pearls. Staphylococcus species do not divide on a regular plane.

Bacilli :

Streptococcus bacteria subdivide into Strep. pyogenes (Group A), Strep. agalactiae (Group B), enterococci (Group D), Strep viridans, and Strep pneumonia. Gram-positive bacilli (rods) subdivide according to their ability to produce spores.

• If complete hemolysis of the blood cells is observed, the streptococci are classified as beta'hemolytic. M protein is considered the most important virulence component of S. pyogenes. Antibodies that react with M protein are produced in response to infection. A prospective antistreptococcus vaccination based on the M protein or a derivative of it is being studied.

Tetrads :

The tetrad occurs in a subgroup of the cocci where the bacterium divides in two planes to form a square of four bacteria called a tetrad. Some examples of tetrad-forming bacteria are the lactic acid bacilli, Aerococcus, a urinary tract pathogen and Pediococcus and Tetragenococcus, both of which ferment foods.

• Tetrads are groups of four cocci that are positioned in the same plane (e.g. Micrococcus sp.). Sarcina is a bacterial genus that consists of eight cocci arranged in a cuboidal pattern (e.g. Sarcina ventriculi).

Sarcinae :

Sarcina is a Gram-positive cocci bacterium genus belonging to the Clostridiaceae family. After the cuboidal (2x2x2) cellular affiliations they create during division along three planes, the genus gets its name from the Latin word "sarcina," which means "pack or bundle."

• Diplococci are pairs of cocci; streptococci are rows or chains of such cells; staphylococci are grapelike clusters of cells; sarcinae are packets of eight or more cells; and tetrads are groups of four cells in a square layout. Variations in the reproductive mechanism of bacteria result in these distinctive groups.

Strepto :

a combining term that means "twisted" and is used to make composite words: streptococcus

• Streptococcus- a spherical or oval bacteria of the genus Streptococcus that occurs in pairs or chains and is harmful for humans, causing scarlet fever, tonsillitis, and other diseases.

Fastidious :

Streptococcus is a genus of gram-positive cocci that are organized in chains. These are fastidious bacteria that need blood or serum added to their culture medium. They are non-motile and do not produce spores. Most are facultative anaerobes, which means they can grow on enriched media.

• Streptococcus pyogenes - it's a nutrient-concious bacteria that ferments glucose to make lactic acid and has stringent growth needs. This section explains the growth and maintenance of S. pyogenes to help in the research of this organism.

Can Grow In Salt :

On the basis of their salt tolerance, the salt tolerance test is used to identify enterococcal group D Streptococcus. Several bacteria, notably viridians streptococci, have been classified based on their capacity to thrive in the presence of a varying quantity of sodium chloride (NaCl).

• The non-beta hemolytic streptococci (viridans, and non-enterococcal group D) do not grow in 6.5% NaCl broth; but some of the beta-hemolytic strains may grow in the broth.

Can Grow In Acid :

Some streptococci can create acids, grow in acidic surroundings (acidophilia), make acids at low pH levels (aciduric capability), and synthesis intracellular and external polysaccharides.

• Dental caries is associated mainly with acid production at pH values below 5 by nongrowing bacteria in dental plaque. Oral streptococci cannot grow at pH above about 5, although they can lower the pH of suspensions or biofilms to values of 4 or lower.

Normal Flora of The Skin:

Bacteria make up the vast bulk of typical flora. Skin and nasal membranes are typically infected with Staphylococcus epidermidis.

• Staphylococcus epidermidis is a Gram-positive bacterium that belongs to the Staphylococcus genus, which has around 40 species. It is found in marine sponges and is part of the normal human flora, most usually the skin flora and less commonly the mucosal flora.

Sources: ( https://www.cdc.gov/ )