TABLE 3.
Features of conjugative junctionsa
| Donor strain plasmid(s) | Mean junction length (nm) ± SE (no. of junctions measured) | Median junction length (nm) | Mean no. of interruptions along junction length ± SE (no. of junctions measured) |
|---|---|---|---|
| RP4 | 193 ± 41 (22) | 117 | 1.1 ± 0.4 (22) |
| Tra1 + Tra2 | 281 ± 41 (50) | 188 | 0.9 ± 0.3 (10) |
| Tra2 alone (pili unprocessed) | 86 ± 22 (21) | 42 | 2.3 ± 1.0 (6) |
| Tra2 + TraF (pili processed) | 111 ± 17 (17) | 104 | 2.3 ± 0.4 (7) |
| Pilin-minus (trbC) | 199 ± 29 (71) | 99 | 1.7 ± 0.4 (20) |
| Null | 25 ± 5 (18) | 18 | NA |
a
The features of conjugative junctions in RP4-mediated matings (and in matings where the donor carried different RP4 transfer components) were determined. Conjugational junction lengths are defined as the areas of close approach between outer membranes with an electron-dense area filling the intercellular space (including interruptions). The number of interruptions per junction (defined as areas where outer membranes deviated from a straight, tightly appressed course and lacked electron density between outer membranes) was determined along the length of a junction. NA, not applicable.