The secret to the pathogenicity of S. sanguis must lie within its DNA, and you and others at VCU have resolved to sequence its entire genome. By comparing its genome to those of other Streptococci with different life styles, you hope to uncover the basis for its role in plaque formation and heart disease.

Shotgun sequencing begins with breaking the chromosome of roughly 2 million base pairs into overlapping fragments about 2000 bp in size. These fragments are then cloned into bacterial plasmids for sequence analysis. The individual sequences obtained must then be reassembled to arrive at the sequence of the entire chromosome. Back to main Scenario page      back one page     continue