Table 1.

Strains and plasmids used in this study.

	Key features	Reference
Strains
E. coli DH5αZ1	Δ(argF-lac)169 ϕ80ΔlacZ58(M15) glnV44 (AS) rfbD1 gyrA96 (NalR) recA1 endA1 spoT1 thi-1 hsdR17 Z1(lacR tetR SpR)	[36]
S. aureus RN4220	Avirulent mutant of NCTC 8325-4 that accepts foreign DNA	[43]
S. aureus RN6390	Laboratory virulent strain derived from NCTC 8325	[43]
S. aureus COL	Highly methicillin resistant clinical isolate	[44]
S. aureus Newman	Virulent strain containing a high level of Clumping Factor	[45]
S. aureus RN4220 hfq	RN4220, Δhfq::cat, CmR	This work
S. aureus RN6390 hfq	RN6390, Δhfq::cat, CmR	This work
S. aureus COL hfq	COL, Δhfq::cat, CmR	This work
S. aureus Newman hfq	Newman, Δhfq::cat, CmR	This work
Plasmids
PMAD	Thermosensitive plasmid in S. aureus derived from pRN5101 and containing the bgaB gene, EryR, AmpR	[38]
pMADΔhfq::cat	pMAD containing up- and downstream regions from hfq gene cloned on either side of the Cm cassette (cat); used for construction of the S. aureus RN4220 hfq mutant, EryR, AmpR, CmR, bgaB	This work