Table 4a.
The effects of amino acids changes in the last two codons of RecN on log/mini-cell phenotype and the ability to partition the nucleoids when overproducing the RecN protein1
| Strain | recNp | recN | clpP | hupA | Average Cell Area | %Cells (Area>300) |
Bumps | Mini cells | Partitioning Ability2 |
|---|---|---|---|---|---|---|---|---|---|
| SS7117 | + | + | + | + | 160 | 1 | 0 | 0 | ND |
| SS9189 | + | + | Δ | + | 160 | 1 | 0.01 | 0.01 | ND |
| SS10336 | op | + | + | + | 160 | 1 | 0 | 0 | ND |
| SS10337 | op | + | Δ | + | 280 | 20 | 0.03 | 0.04 | ND |
| SS12691 | op | 4172 (DD) | + | + | 180 | 3 | 0 | 0 | ND |
| SS12692 | op | Δ4173 (AA) | + | + | 180 | 3 | 0 | 0 | ND |
| SS12693 | op | 4174 (SV) | + | + | 320 | 20 | 0.01 | 0.01 | ND |
| SS6321 | + | + | + | mCherry | 170 | 1 | 0 | 0 | ++ |
| SS10350 | + | + | Δ | mCherry | 160 | 1 | 0.01 | 0 | ++ |
| SS10346 | op | + | + | mCherry | 180 | 2 | 0 | 0 | ++ |
| SS10353 | op | + | Δ | mCherry | 280 | 18 | 0.04 | 0.05 | − |
| SS12252 | op | 4172 (DD) | + | mCherry | 190 | 4 | 0 | 0 | ++ |
| SS12281 | op | Δ4173 (AA) | + | mCherry | 210 | 5 | 0 | 0 | ++ |
| SS12283 | op | 4174 (SV) | + | mCherry | 310 | 21 | 0.01 | 0.01 | − |
The letters in parentheses after the allele number represent the amino acids changed or deleted. 1900–4000 cells were counted for each strain. Average cell area is given in number of pixels. Cells were grown as mentioned the Experimental Procedures. All statistical tests were done using the Student’s t-test. The p value for the significance in the difference in average cell area between recNop recN4172 (A552D, A553D), recNop del(recN)4173, and recNop recN4174 (A552S, A553V), (SS12691, SS12692, and SS12693, respectively, or SS12252, SS12281, and SS12283, respectively) and recNop mutant (SS10336 or SS10346) is highly significant (p<0.001).
Example of cells that are properly partitioning their chromosome and ones that are not are shown in Figure 5.