TABLE 1.

Strains and fusions used in this study

Strain	Relevant characteristic(s)	Reference
MG1363	Plasmid-free derivative of NCDO0712	14
YS5F	MG1363 Δopp ΔpepO1 ΔdtpT dppF::pINTdppF Eryr	45
JIM7506	MG1363 bearing pepO1::lacZ fusion integrated in opp-pepO1 locus, Eryr	20
JIM8106	JIM7506 codY::ISS1 Eryr	20