TABLE 5.

Characteristics of the Streptomyces strains used in this work

Strain	Characteristic(s)	Plasmid content	Origin or reference(s)
S. clavuligerus ATCC 27064	Control strain	Standard copy no. of pSCL1, pSCL2, pSCL4	ATCC
S. clavuligerus ΔoppA2::aac	oppA2 deleted; apramycin resistant; previously named S. clavuligerus ΔoppA2::aac pSCL4+	Standard copy no. of pSCL1, pSCL2, pSCL4	18
S. clavuligerus pSCL4−	Lacking plasmid pSCL4	Lacking plasmid pSCL4; standard copy no. of pSCL1 and pSCL2	18
S. clavuligerus ΔoppA2::aac pSCL4−	oppA2 deleted; apramycin resistant; lacking plasmid pSCL4	Lacking plasmid pSCL4; standard copy no. of pSCL1 and pSCL2	18
S. clavuligerus ΔoppA2::acc[pAV11-oppA2]	oppA2 inserted in plasmid pAV11 to complement the oppA2-deletion in the parental strain; apramycin and hygromycin resistant	Standard copy no. of pSCL1, pSCL2, pSCL4	This work
S. clavuligerus ΔoppA2::acc[pAV11]	oppA2 deleted; apramycin, thiostrepton resistant	Standard copy no. of pSCL1, pSCL2, pSCL4	This work
S. clavuligerus pyc::aph	ceaS2 disrupted; kanamycin resistant	Standard copy no. of pSCL1, pSCL2, pSCL4	11, 36
S. clavuligerus RFL35	blS2 deleted; thiostrepton resistant	Standard copy no. of pSCL1, pSCL2, pSCL4	43
S. clavuligerus cyp::aph	cyp disrupted; kanamycin resistant	Standard copy no. of pSCL1, pSCL2, pSCL4	25
S. clavuligerus orf14::aph	orf14 disrupted; kanamycin resistant	Standard copy no. of pSCL1, pSCL2, pSCL4	25
S. clavuligerus oppA1::aac	oppA1 disrupted; apramycin resistant	Standard copy no. of pSCL1, pSCL2, pSCL4	15