Streptococcus mutans bacteria, SEM
^BStreptococcus mutans.^b Coloured scanning electron micrograph (SEM) of ^IStreptococcus^i ^Imutans^i bacteria. These are Gram-positive, non-motile, spherical bacteria (cocci) which typically form chains of cells (as seen here). ^IS.^i ^Imutans^i is found in the mouth cavity. It is one of the principal bacteria causing plaque formation on teeth, and a major cause of tooth decay. Magnification: x6,750 at 6x7cm size. x11,000 at 4×5 inch size.