Distribution of Twelve Linear Extrachromosomal DNAs in Natural Isolates of Lyme Disease Spirochetes

↵a The United States state from which each of the strains was isolated is indicated in parentheses next to the strain name. Probes were picked from E. coli pUC18 plasmid clones used in the genone sequencing project (6, 12). Values in table are sizes in kilobase pairs for plasmids that hybridize to the indicated DNA probes (accurate to about ±0.5, ±1.5, and ±3 kbp for 5 to 10, 10 to 30, and 30 to 60 kbp ranges, respectively). —, no hybridization was seen. Values in parentheses indicate relatively weak hybridization.

↵a Strain names are followed by the name of the United States state (in parentheses) in which they were isolated. Each of the remaining columns represents a different DNA probe from Table 1, going from left to right across each plasmid map (orientation as in references 8 and12). −, no hybridization; +, hybridization occurred with a plasmid similar in size (<15% different) to the B31 plasmid from which the probe was derived (hybridization to other plasmids may also have occurred); + and ✙, hybridization toonly a plasmid(s) >15% different in size from the B31 plasmid from which the probe was derived; ✙, hybridization in that strain only to a plasmid(s) of a size >10% different from the plasmid(s) with which other probes from that B31 plasmid react.