What does Streptococcus pneumoniae look like?
What does Streptococcus pneumoniae look like?
Streptococcus pneumoniae cells are Gram-positive, lancet-shaped cocci (elongated cocci with a slightly pointed outer curvature). Usually, they are seen as pairs of cocci (diplococci), but they may also occur singly and in short chains. When cultured on blood agar, they are alpha hemolytic.
What does diplococci look like?
A diplococcus (plural diplococci) is a round bacterium (a coccus) that typically occurs in the form of two joined cells.
What is the shape of Diplococcus pneumoniae?
Streptococcus pneumoniae is a gram-positive, α-hemolytic, lancet-shaped diplococcus and is bile soluble and optochin sensitive.
What does cocci bacteria look like?
A coccus (plural cocci) is any bacterium or archaeon that has a spherical, ovoid, or generally round shape. Bacteria are categorized based on their shapes into three classes: cocci (spherical-shaped), bacillus (rod-shaped) and spirochetes (spiral-shaped) cells.
What does beta hemolysis look like?
Beta-hemolysis (β-hemolysis), sometimes called complete hemolysis, is a complete lysis of red cells in the media around and under the colonies: the area appears lightened (yellow) and transparent. Streptolysin, an exotoxin, is the enzyme produced by the bacteria which causes the complete lysis of red blood cells.
What does Streptococcus pneumoniae look like under a microscope?
Streptococcus pneumoniae bacteria are gram-positive cocci arranged in chains and pairs (diplococci) on microscopic examination. A green, α-hemolytic, zone surrounds S. pneumoniae colonies on blood-agar plates.
What shape are streptococci?
Streptococci are nonmotile, Gram-positive, nonsporeforming bacteria, that live in pairs or chains of varying length. They are characteristically round or ovoid in shape. Most Streptococci are facultative anaerobes, although some are obligate anaerobes. They usually require a complex culture medium in order to grow.
What causes Diplococcus pneumonia?
It can be a cause of neonatal infections. Streptococcus pneumoniae is the main cause of community acquired pneumonia and meningitis in children and the elderly, and of sepsis in those infected with HIV….
| Streptococcus pneumoniae | |
|---|---|
| Species: | S. pneumoniae |
| Binomial name | |
| Streptococcus pneumoniae (Klein 1884) Chester 1901 |
What Gram stain is Streptococcus?
Streptococci are Gram-positive, nonmotile, nonsporeforming, catalase-negative cocci that occur in pairs or chains. Older cultures may lose their Gram-positive character.
How are cocci transmitted?
Coccidioidomycosis is typically transmitted by inhalation of airborne spores of C immitis or C posadasii (see Etiology). Infection occurs in endemic areas and is most commonly acquired in the summer or the late fall during outdoor activities.
What infection does cocci cause?
The Gram-positive cocci are the leading pathogens of humans. It is estimated that they produce at least a third of all the bacterial infections of humans, including strep throat, pneumonia, otitis media, meningitis, food poisoning, various skin diseases and severe types of septic shock.
Why is beta hemolysis yellow?
