A rugged yet easily navigable fitness landscape
Editor’s summary
How many mutations does it take to move from one genetic fitness peak to another in a fitness landscape? Papkou et al. performed mutagenesis to survey the combinatorial genotypic space of nine nucleotides encoding three successive amino acids in a protein targeted by antibiotics in Escherichia coli. The authors found that most genotypes had low fitness, but that traveling between high fitness peaks required surprisingly few mutations. This work represents an exhaustive examination of more than 260,000 genotypes, surveying a nearly complete network of mutational paths to answer a long-standing question.
—Corinne Simonti