TABLE 2 .
Roles of cro/cI and putative ABC transporter genes in resistance of USA300-derived strains to compound 103
| Strain | Relevant genotypea | MIC of compound 103 (fold increase versus MIC for USA300 WT) |
Expression of SAUSA300_0352 (fold increase versus level in USA300 WT) |
|---|---|---|---|
| GNE0163 | USA300 WT(pMK4) | 1.0 | 1.0 |
| GNE0162 | psarA-SAUSA300_0351_0352_0353 | >32 | 56.9 |
| GNE0107 | cro/cI(M1V)(pMK4) | >32 | 66.2 |
| GNE0109 | cro/cI(M1V)(pcro/cI-cro/cI) | 1.7 | 1.0 |
| GNE0096 | cro/cI(−14G→T)(pMK4) | >32 | 10.9 |
| GNE0097 | cro/cI(−14G→T)(pcro/cI-cro/cI) | 3.0 | 0.1 |
| GNE0099 | cro/cI(−62G→A)(pMK4) | >32 | 5.5 |
| GNE0100 | cro/cI(−62G→A)(pcro/cI-cro/cI) | >32 | 8.0 |
| GNE0173 | Δmcr cro/cI(Q16stop) | >32 | 105 |
| GNE0220 | Δmcr cro/cI(Q16stop) Δ(SAUSA300_0351-SAUSA300_0352-SAUSA300_0353) | 2.0 | NDb |
| GNE0209 | Δmcr cro/cI(Q16stop) ΔSAUSA300_0351 | >32 | 93 |
| GNE0175 | Δmcr cro/cI(Q16stop) SAUSA300_0352(K44A) | 1.0 | 106 |
| GNE0210 | Δmcr cro/cI(Q16stop) ΔSAUSA300_0353 | 1.0 | ND |
a
All strains are USA300 derived, and all plasmids are pMK4 (empty plasmid) or constructed in pMK4. A more detailed description of each strain is given in Table S5 in the supplemental material. SAUSA300_0351 encodes a putative membrane protein, SAUSA300_0352 encodes a putative ABC transporter ATPase, and SAUSA300_0353 encodes a putative permease.
b
ND, not determined.