TABLE 2.
Sequence changes that arose in strain R6 compared to progenitor strain D39a
| Change category (no. of changes) | Description |
|---|---|
| Single-base-pair | |
| changesb (71) | Fifty-one missense (two following frameshift mutations); three nonsense; eight intercistronic (some correlated with changes in transcript levels); nine silent |
| Deletions (6) | ΔC (frameshift); ΔA (intercistronic); ΔA (frameshift); Δ8 bp of adjacent direct repeat (intercistronic); Δ41 bp (intercistronic); Δ7,505 bp that removes part of the capsule biosynthesis (cps) locus (50) |
| Insertions (4) | Insertion of two 456-bp direct repeat units (912 bp) in spr0075; inversion and insertion of 25-bp internal to cps2A at the junction of cps deletion; insertion of 30-bp adjacent direct repeat (in frame) in pcpA, encoding choline-binding protein; insertion of 2 bp (frameshift) |
a
Specific mutations are listed in Tables S1 and S3 in the supplemental material. R6 has also lost cryptic plasmid pDP1 (see the text).
b
There were 45 transition mutations: 19 GC to AT (27%) and 26 AT to GC (37%). There were 26 transversion mutations: 7 GC to TA (10%); 10 AT to CG (14%); 7 GC to CG (10%); and 2 AT to TA (3%).