Bacterial Adaptation through Loss of Function
Figure 3
Contributions of null mutations to fitness by functional category.
(A,B) Percentage of members of each class for which null mutations caused significantly beneficial (A) or deleterious (B) fitness effects in at least 5%, 25%, 50%, and 75% of the 144 conditions analyzed. Colored labels on the x-axis indicate classes with a significant enrichment in null mutations (q<0.01 by a resampling test; see main text and Table S2). (C,D) Circles: total number of significant beneficial (C) or deleterious (D) null mutations present in each class across all conditions in our meta-analysis. Box plots: simulated null distribution of the same statistic for each class (see main text and Materials and Methods for details). Classes showing significant enrichments (q<0.01) relative to the corresponding null distribution have their label colored on the x-axis and the circle representing their observed value filled in green. No bar appears for the RNA class in panel A because fewer than 5% of the conditions had beneficial nulls from the RNA class; see main text for details. All classifications are from GenProtEC (http://genprotec.mbl.edu/files/geneproductfunctions.txt).