Figure 5.—
Stability of plasmids pP21 (evolved in host P21) compared to stability of the ancestral plasmid pB10 in four naive hosts: two unfavorable hosts (A, P. koreensis R28; B, P. putida H2) and two favorable hosts (C, E. coli K12; D, P. putida UWC1). Data for plasmid pB10 are averages from five replicate-stability assays; data for plasmids pP21 represent averages from five evolved plasmids, one per lineage (same five plasmids that were tested in host P21anc, Figure 3). Error bars represent standard deviations. In C and D, open instead of solid squares are used for pP21 plasmids to show both symbols. Note that the y-axis of A is on a logarithmic scale. In E. coli and P. putida, both ancestral and evolved plasmids were stable for at least 200 and 300 generations (data not shown).