FIG. 2.

Challenge kinetics of alterations in the relative abundance of mutants in comEC (▪), coiA (⧫), comGD (▾), and comD (×) genes in a 2,500-CFU mutant library. Challenged and nonchallenged mutant libraries were grown for about 15, 18, 21, or 24 generations, and signal intensity ratios for each gene were determined by GAF. The average absolute ratio (•) was calculated at different time points, excluding known competence genes and genes in the Δcps PCR product. The dotted line indicates a signal intensity ratio of 1.