n.
Any of the spheroidal bacteria that make up the genus Streptococcus .
The cells characteristically group together in chains resembling a string of beads. Streptococci are gram-positive (see gram stain ) and stationary and do not require oxygen. Some species cause infections, including rheumatic fever , scarlet fever , strep throat, and tonsillitis . Others are used in commercial starters for the production of butter, cultured buttermilk, and certain cheeses. See also pneumococcus .