Table 4.
Mutations associated with resistance to linezolid in ≥2 isolates reported by ≥2 studies or ≥3 isolates reported by ≥1 studya
| Gene | aa change [nt] and numbering system (H37Rv unless specified) | MIC summary | MIC change by mutant/study | Data summary | References (in order of data in column 4 and separated by semicolons) |
|---|---|---|---|---|---|
| rplC | C154R [T460C] | 4–32× | 4–16× (4 isolates), ≥1× (3 isolates), MIC not stated (2 isolates); MIC 16.0–32.0 mg/L (3 isolates, 1 double mutation, no parent); >8× (15 isolates); MIC ≥1 mg/L (clinical isolates, no pretreatment data available for 6 of 9 isolates, 3 isolates with mixed mutations); 4× (2 isolates); MIC 4–16 mg/L (2 isolates, no parent); 17× (12 isolates); MIC 4.0 mg/L (clinical isolate, no parent); 8× (2 isolates); 16–32× (7 isolates) | 37 in vitro spontaneous mutants, 22 clinical isolates (2 isolates with heteroresistance, 2 isolates with double mutations), 8 isolates with mutations via plasmid complementation | Beckert 2012;51Zhang 2014;49 Zhang 2016;52Zimenkov 2017;39 Makafe 2016;53Pang 2017;41 McNeil 2017;54Perdigao 2016;55 Lee 2012;58 Balasubramanian 201459 |
| rrl | [G2299T] in H37Rv numbering ([G2061T] in E. coli numbering) | 22–53× | 32× (4 isolates); MIC 32 mg/L (2 clinical isolates, no parent strain); 22–53× | 8 in vitro spontaneous mutants, 2 clinical isolates (1 double mutation) | Hillemann 2008,50Zhang 2014,49 McNeil 201754 |
| rrl | [G2814T] in H37Rv numbering ([G2576T] in E. coli numbering) | 4–32× | 16× (1 isolate); 4–16× (2 isolates, double mutations); MIC ≥1 mg/L (clinical isolate, no pretreatment data available); 8–17× (4 isolates, MIC in solid medium), 32× (1 isolate, MIC90 in liquid medium); MIC ≤1.0 mg/L (clinical isolate, no parent, phenotypically susceptible); 8× (1 isolate) | 6 in vitro selected isolates, 5 clinical isolates (2 isolates with double mutations) | Hillemann 2008,50Somoskovi 201547and Bloemberg 2015,35Zimenkov 2017,39 McNeil 2017,54Banu 2017,56 Lee 201258 |
| rrl | [G2270T], [G2270C] | 8× | 8× (6 isolates); 8× | 7 in vitro spontaneous mutants (8 strains with mutation, 1 without MIC testing) | Zhang 2016,52 Balasubramnian 201459 |
| rrl | [G2746A] | 8× | 8× (5 isolates) | 5 in vitro spontaneous mutants (8 strains with mutation generated, but only 5 with MIC testing) | Zhang 201652 |
a
Low confidence data underlined.