Relative gene conversion frequencies obtained with rrnA fragments carrying a resistance-conferring mutation at 23S rRNA position 2058 or 2059 (A) and rrnA fragments carrying a resistance-conferring mutation at 16S rRNA position 1491 (B). Shown are the median values (horizontal lines), 95% confidence intervals (rectangular boxes), and outliers (vertical lines) of gene conversion frequencies calculated from the numbers of cells that gained paromomycin or clarithromycin resistance in 10 independent cultures of each strain. *, significant increase of gene conversion frequencies compared to the wild type (Student's t test; P < 0.05). wt, M. smegmatis wild-type strain; uvrB, uvrD1, and uvrB uvrD1, M. smegmatis NER mutant strains.