An internationally spread clone of Streptococcus pneumoniae evolves from low-level to higher-level penicillin resistance by uptake of penicillin-binding protein gene fragments from nonencapsulated pneumococci.

An internationally spread clone of Streptococcus pneumoniae evolves from low-level to higher-level penicillin resistance by uptake of penicillin-binding protein gene fragments from nonencapsulated pneumococci.