Streptococcus pneumoniae , or pneumococcus , is a Gram-positive , alpha-hemolytic diplococcus aerotolerant anaerobe and a member of the genus Streptococcus . Streptococcus pneumoniae , or pneumococcus , is Gram-positive , alpha-hemolytic , bile-soluble aerotolerant , anaerobic member of the genus Streptococcus .