TABLE 1.

Streptococcus pneumoniae strains

Reference strain	Relevant characteristics	Reference
R6	Penicillin-sensitive laboratory strain	4
R6ciaR::aad9	CiaR disruption (ΔciaR)	39
R6pbp2xC606	PBP2x: M289T, G422D, G597D, G601V	40
2349	Spain23F-1; mosaic PBPs2x, -1a, -2b	51