Identifying non-capsulate strains of Streptococcus pneumoniae isolated from eyes.

Over six months 10 biochemically and physiologically atypical strains of Streptococcus pneumoniae were isolated from eye swabs. Conventional methodology showed that these strains possessed characteristics of both S pneumoniae and other alpha haemolytic streptococci. The use of sodium dodecyl sulphate - polyacrylamide gel electrophoresis (SDS-PAGE) enabled us to characterise these strains as S pneumoniae. Loss of the capsule seemed to be associated with atypical biochemical properties.