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.

What is the shape of Streptococcus pneumoniae bacteria?

Streptococcus pneumoniae are lancet-shaped, gram-positive, facultative anaerobic bacteria with more than 100 known serotypes. Most S. pneumoniae serotypes can cause disease, but only a minority of serotypes produce the majority of pneumococcal infections.

What color is Streptococcus pneumoniae on blood agar?

green
On a blood agar plate (BAP), colonies of S. pneumoniae appear as small, grey, moist (sometimes mucoidal), colonies and characteristically produce a zone of alpha-hemolysis (green) (Figure 1).

What is the shapes of Streptococcus?

Streptococci are nonmotile, Gram-positive, nonsporeforming bacteria, that live in pairs or chains of varying length. They are characteristically round or ovoid in shape.

What is the color of Streptococcus?

MACROSCOPIC APPEARANCE. Streptococcal colonies vary in color from gray to whitish and usually glisten. Often dry colonies are observed. Encapsulated strains may appear mucoid.

What does Streptococcus bacteria look like?

The term streptococcus (“twisted berry”) refers to the bacteria’s characteristic grouping in chains that resemble a string of beads. Streptococci are microbiologically characterized as gram-positive and nonmotile.

What does the Streptococcus bacteria look like?

What is the structure of streptococcus?

Structure. Streptococci are Gram-positive, nonmotile, nonsporeforming, catalase-negative cocci that occur in pairs or chains. Older cultures may lose their Gram-positive character. Most streptococci are facultative anaerobes, and some are obligate (strict) anaerobes.