The highly conserved serine threonine kinase StkP of Streptococcus pneumoniae contributes to penicillin susceptibility independently from genes encoding penicillin-binding proteins

Table 1 Strains and plasmids used in the study

Strain or plasmid	Genotype or description	Phenotype^a	Source or reference
*S. pneumoniae*
R6	Non-capsulated D39 derivative, susceptible reference strain; genome sequence available (R6)	AtbS	Laboratory stock
ATCC BAA-334	Virulent reference strain, genome sequence available (TIGR4)	AtbS	ATCC
ATCC 51916	Reference strain Tennessee 23F-4	PenR, EryR,	ATCC
ATCC 700670	Reference strain Spain 6B-2	PenR, CmR, TetR	ATCC
ATCC 700673	Reference strain Hungary 19A-6	PenR, EryR, CmR, TetR	ATCC
URA1258	Multiresistant strain closely related to Spain 23F-1 clone	PenR, CmR, TetR	[21]
Cp1015	D39 derivate, str1; hexA	SmR	[31]
Cp1016	D39 derivate, str1; hexA, rif23	RifR	[31]
Cp7000	Cp1015, stkP::cat	SmR CmR	This study
Pen1	Cp1015, penA, and pbpX from URA1258	SmR PenR	This study
Pen2	Cp1015, penA, pbpX and pbp1A from URA1258	SmR PenR	This study
Pen1STK	Cp1015Pen1, stkP::cat	SmR PenR CmR	This study
Pen2STK	Cp1015Pen2, stkP::cat	SmR PenR CmR	This study
*E. coli*
DH5α	F^-, φ80lac ZΔM15, Δ(lac ZYA-arg F)U169, deo R, rec A1, end A1, hsd R17(rk^-, mk⁺), pho A, sup E44, λ^-, thi^-1, gyr A96, rel A1	NalR	[8]
plasmid
plSTK	3.5 kb EcoRI/SacII fragment containing stkP and flanking regions with cat cassette inserted	ApR, CmR	[6]

^a: ApR, resistant to ampicillin; AtbS, Susceptible to all tested antibiotics; CmR, resistant to chloramphenicol; EryR, resistant to erythromycin; NalR, resistant to nalixidic acid; PenR, non-susceptible to penicillin G; RifR, resistant to rifamycin; SmR, resistant to streptomycin; TetR, resistant to tetracycline.

ISSN: 1471-2180