Bile solubility

Pneumococcus - gallery

Streptococcus pneumoniae or pneumococci are gram-positive cocci in pairs, which may be capsulated. Colonies are 1-2mm, α-haemolytic and may appear as ‘draughtsman’ colonies (due to autolysis of the organisms). If incubated in anaerobic conditions, the colonies may appear larger and more mucoid. It is, like other Streptococcus spp., catalase-negative. Traditionally, a few of the properties of the pneumococcus were exploited to […]